refactor(ui): scroll mechanism — derive paged, defer render, split edges

Four-level refactor of the chat-window scrolling state:

L1. Extract win_page_space() and unify the two-branch clamp at the end of
    win_page_down into a single last_page_start formula. Removes the
    duplicated `getmaxy(stdscr) - 4` magic across page_up / page_down /
    sub_page_up / sub_page_down and the off-by-one between the two clamp
    branches.

L2. Remove ProfLayout::paged sticky flag. Replace with win_is_paged(),
    derived from y_pos and the current pad height. Eliminates the entire
    bug class of "stuck paged=1" — there is no flag to drift, no manual
    reset to forget. The earlier non-CHAT bottom-reach reset, the
    WIN_SCROLL_REACHED_BOTTOM reset, the win_clear paged=1 line, and the
    cl_ev_send_ai_msg paged=0 workaround all collapse into "y_pos governs
    everything." cl_ev_send_ai_msg now calls win_move_to_end so the user's
    own message is visible after scroll-up.

L3. _win_printf no longer drops messages when paged. The line is appended
    to the buffer and to the curses pad unconditionally; it lands below
    the visible viewport so the user's reading position is unchanged. The
    unread badge still increments. Suppressed messages are no longer lost
    forever — page-down naturally reveals them.

L4. Replace the win_scroll_state_t enum (INNER / REACHED_TOP /
    REACHED_BOTTOM, conflating layout edge with DB exhaustion) with a
    ScrollEdges struct of two independent booleans:
      db_exhausted_above — a previous page-up DB fetch returned empty
      db_exhausted_below — same for page-down
    The flags are flipped to TRUE on DB_RESPONSE_EMPTY and cleared by a
    scroll in the opposite direction (so MAM late-delivery and /history
    switch can re-trigger fetches). Buffer-edge state is no longer
    encoded here — y_pos handles that.

Tests: stub_ui gets a no-op win_move_to_end. 545/545 unit tests pass.

Makefile.am

@@ -37,6 +37,7 @@ core_sources = \
 	src/ui/window_list.c src/ui/window_list.h \
 	src/ui/rosterwin.c src/ui/occupantswin.c \
 	src/ui/buffer.c src/ui/buffer.h \
+	src/ui/aiwin.c \
 	src/ui/chatwin.c \
 	src/ui/mucwin.c \
 	src/ui/privwin.c \
@@ -78,7 +79,8 @@ core_sources = \
 	src/plugins/themes.c src/plugins/themes.h \
 	src/plugins/settings.c src/plugins/settings.h \
 	src/plugins/disco.c src/plugins/disco.h \
-	src/ui/tray.h src/ui/tray.c
+	src/ui/tray.h src/ui/tray.c \
+	src/ai/ai_client.h src/ai/ai_client.c
 
 unittest_sources = \
 	src/xmpp/contact.c src/xmpp/contact.h src/common.c \
@@ -89,6 +91,7 @@ unittest_sources = \
 	src/xmpp/chat_state.h src/xmpp/chat_state.c \
 	src/xmpp/roster_list.c src/xmpp/roster_list.h \
 	src/xmpp/xmpp.h src/xmpp/form.c \
+	src/ai/ai_client.h src/ai/ai_client.c \
 	src/ui/ui.h \
 	src/otr/otr.h \
 	src/pgp/gpg.h \
@@ -138,6 +141,7 @@ unittest_sources = \
 	tests/unittests/xmpp/stub_message.c \
 	tests/unittests/ui/stub_ui.c tests/unittests/ui/stub_ui.h \
 	tests/unittests/ui/stub_vcardwin.c \
+	tests/unittests/ui/stub_ai.c \
 	tests/unittests/log/stub_log.c \
 	tests/unittests/chatlog/stub_chatlog.c \
 	tests/unittests/database/stub_database.c \
@@ -174,6 +178,7 @@ unittest_sources = \
 	tests/unittests/test_callbacks.c tests/unittests/test_callbacks.h \
 	tests/unittests/test_plugins_disco.c tests/unittests/test_plugins_disco.h \
 	tests/unittests/test_forced_encryption.c tests/unittests/test_forced_encryption.h \
+	tests/unittests/test_ai_client.c tests/unittests/test_ai_client.h \
 	tests/unittests/test_database_export.c tests/unittests/test_database_export.h \
 	tests/unittests/test_database_stress.c tests/unittests/test_database_stress.h \
 	tests/unittests/unittests.c

src/ai/ai_client.h

@@ -0,0 +1,257 @@
+#ifndef AI_CLIENT_H
+#define AI_CLIENT_H
+
+#include <glib.h>
+
+/**
+ * @brief AI message structure for conversation history.
+ */
+typedef struct ai_message_t
+{
+    gchar* role;    /* "user" or "assistant" */
+    gchar* content; /* Message content */
+} AIMessage;
+
+/**
+ * @brief AI provider configuration.
+ */
+typedef struct ai_provider_t
+{
+    gchar* name;           /* Provider name (e.g., "openai", "perplexity") */
+    gchar* api_url;        /* API endpoint URL */
+    gchar* org_id;         /* Optional organization ID */
+    gchar* project_id;     /* Optional project ID (for some providers) */
+    gchar* default_model;  /* Default model for this provider */
+    GHashTable* settings;  /* Extensible per-provider settings (e.g., tools=enabled, search=disabled) */
+    GList* models;         /* Cached models (gchar*) */
+    gboolean models_fresh; /* Whether models cache is current */
+    gint32 ref_count;      /* Reference count (atomic) */
+} AIProvider;
+
+/**
+ * @brief AI chat session structure.
+ */
+typedef struct ai_session_t
+{
+    gchar* provider_name; /* Provider name */
+    AIProvider* provider; /* Provider configuration */
+    gchar* model;         /* Model identifier (e.g., "gpt-4", "sonar") */
+    gchar* api_key;       /* API key for this session */
+    GList* history;       /* Conversation history (GList of AIMessage*) */
+    gint32 ref_count;     /* Reference count (atomic) */
+} AISession;
+
+/* ========================================================================
+ * Provider Management
+ * ======================================================================== */
+
+/**
+ * Initialize the AI client and load default providers.
+ */
+void ai_client_init(void);
+
+/**
+ * Shutdown the AI client and free resources.
+ */
+void ai_client_shutdown(void);
+
+/**
+ * Get a provider by name.
+ * @param name The provider name (e.g., "openai", "perplexity")
+ * @return AIProvider*, or NULL if not found
+ */
+AIProvider* ai_get_provider(const gchar* name);
+
+/**
+ * Add or update a provider configuration.
+ * @param name The provider name
+ * @param api_url The API endpoint URL
+ * @param org_id Optional organization ID (can be NULL)
+ * @return New AIProvider* (caller must unref when done)
+ */
+AIProvider* ai_add_provider(const gchar* name, const gchar* api_url, const gchar* org_id);
+
+/**
+ * Remove a provider by name.
+ * @param name The provider name
+ * @return TRUE if provider was removed, FALSE if not found
+ */
+gboolean ai_remove_provider(const gchar* name);
+
+/**
+ * Decrement the reference count of a provider.
+ * @param provider The provider to unreference
+ */
+void ai_provider_unref(AIProvider* provider);
+
+/**
+ * List all configured providers.
+ * @return GList of AIProvider* (caller must not free the list or providers,
+ *         and must not unref the returned providers)
+ */
+GList* ai_list_providers(void);
+
+/**
+ * Find a provider name for autocomplete.
+ * @param search_str The search string
+ * @param previous Whether to go to previous match
+ * @param context Unused
+ * @return Provider name, or NULL if not found
+ */
+gchar* ai_providers_find(const char* const search_str, gboolean previous, void* context);
+
+/**
+ * Find a model name for autocomplete.
+ * @param search_str The search string
+ * @param previous Whether to go to previous match
+ * @param context ProfAiWin* for the current session
+ * @return Model name, or NULL if not found
+ */
+gchar* ai_models_find(const char* const search_str, gboolean previous, void* context);
+
+/**
+ * Get the API key for a provider.
+ * @param provider_name The provider name
+ * @return The API key, or NULL if not set (caller must free)
+ */
+gchar* ai_get_provider_key(const gchar* provider_name);
+
+/**
+ * Set the API key for a provider.
+ * @param provider_name The provider name
+ * @param api_key The API key to set
+ */
+void ai_set_provider_key(const gchar* provider_name, const gchar* api_key);
+
+/**
+ * Set the default model for a provider.
+ * @param provider_name The provider name
+ * @param model The default model name
+ */
+void ai_set_provider_default_model(const gchar* provider_name, const gchar* model);
+
+/**
+ * Get the default model for a provider.
+ * @param provider_name The provider name
+ * @return The default model name (caller must not free), or NULL if not set
+ */
+const gchar* ai_get_provider_default_model(const gchar* provider_name);
+
+/**
+ * Set a custom setting for a provider.
+ * @param provider_name The provider name
+ * @param setting The setting key (e.g., "tools", "search")
+ * @param value The setting value
+ */
+void ai_set_provider_setting(const gchar* provider_name, const gchar* setting, const gchar* value);
+
+/**
+ * Get a custom setting for a provider.
+ * @param provider_name The provider name
+ * @param setting The setting key
+ * @return The setting value (caller must free), or NULL if not set
+ */
+gchar* ai_get_provider_setting(const gchar* provider_name, const gchar* setting);
+
+/**
+ * Fetch available models from a provider's API.
+ * @param provider_name The provider name
+ * @param user_data User data (ProfAiWin* for UI display)
+ * @return TRUE if the request was successfully queued, FALSE otherwise
+ */
+gboolean ai_fetch_models(const gchar* provider_name, gpointer user_data);
+
+/**
+ * Check if models cache is fresh for a provider.
+ * @param provider_name The provider name
+ * @return TRUE if models are fresh, FALSE otherwise
+ */
+gboolean ai_models_are_fresh(const gchar* provider_name);
+
+/* ========================================================================
+ * Model Parsing (for testing)
+ * ======================================================================== */
+
+/**
+ * Parse model IDs from an OpenAI-compatible API response.
+ * Expected format: {"object":"list","data":[{"id":"model1",...},...]}
+ * @param provider The provider to add models to
+ * @param json The JSON response from the API
+ */
+void ai_parse_models_from_json(AIProvider* provider, const gchar* json);
+
+/* ========================================================================
+ * Session Management
+ * ======================================================================== */
+
+/**
+ * Create a new AI session with the specified provider and model.
+ * @param provider_name The provider name (e.g., "openai")
+ * @param model The model identifier (e.g., "gpt-4")
+ * @return New AISession*, or NULL on failure
+ */
+AISession* ai_session_create(const gchar* provider_name, const gchar* model);
+
+/**
+ * Increment the reference count of an AI session.
+ * @param session The session to reference
+ * @return The same session pointer
+ */
+AISession* ai_session_ref(AISession* session);
+
+/**
+ * Decrement the reference count and free the session when it reaches zero.
+ * @param session The session to unreference
+ */
+void ai_session_unref(AISession* session);
+
+/**
+ * Add a message to the session history.
+ * @param session The session
+ * @param role The message role ("user" or "assistant")
+ * @param content The message content
+ */
+void ai_session_add_message(AISession* session, const gchar* role, const gchar* content);
+
+/**
+ * Clear the conversation history.
+ * @param session The session
+ */
+void ai_session_clear_history(AISession* session);
+
+/**
+ * Get the current model for a session.
+ * @param session The session
+ * @return The model name (caller must not free)
+ */
+const gchar* ai_session_get_model(AISession* session);
+
+/**
+ * Set the model for a session.
+ * @param session The session
+ * @param model The model name
+ */
+void ai_session_set_model(AISession* session, const gchar* model);
+
+/* ========================================================================
+ * Request Handling
+ * ======================================================================== */
+
+/**
+ * Send a prompt to the AI provider asynchronously.
+ * @param session The AI session containing provider and model
+ * @param prompt The prompt to send
+ * @param user_data User data (ProfAiWin* for UI display)
+ * @return TRUE if the request was successfully queued, FALSE otherwise
+ */
+gboolean ai_send_prompt(AISession* session, const gchar* prompt,
+                        gpointer user_data);
+
+/**
+ * Escape a string for JSON embedding.
+ * @param str The string to escape
+ * @return Newly allocated escaped string (caller must free)
+ */
+gchar* ai_json_escape(const gchar* str);
+
+#endif /* AI_CLIENT_H */

src/command/cmd_ac.c

@@ -66,8 +66,11 @@
 #include "omemo/omemo.h"
 #endif
 
+#include "ai/ai_client.h"
+
 static char* _sub_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _notify_autocomplete(ProfWin* window, const char* const input, gboolean previous);
+static char* _ai_model_autocomplete(ProfWin* window, const char* const input, gboolean previous, const char* prefix);
 static char* _theme_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _autoaway_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _autoconnect_autocomplete(ProfWin* window, const char* const input, gboolean previous);
@@ -137,6 +140,7 @@ static char* _strophe_autocomplete(ProfWin* window, const char* const input, gbo
 static char* _adhoc_cmd_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _vcard_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 static char* _force_encryption_autocomplete(ProfWin* window, const char* const input, gboolean previous);
+static char* _ai_autocomplete(ProfWin* window, const char* const input, gboolean previous);
 
 static char* _script_autocomplete_func(const char* const prefix, gboolean previous, void* context);
 
@@ -280,11 +284,16 @@ static Autocomplete history_switch_ac;
 static Autocomplete color_ac;
 static Autocomplete correction_ac;
 static Autocomplete avatar_ac;
+static Autocomplete ai_subcommands_ac;
+static Autocomplete ai_set_subcommands_ac;
+static Autocomplete ai_set_custom_subcommands_ac;
+static Autocomplete ai_remove_subcommands_ac;
 static Autocomplete url_ac;
 static Autocomplete executable_ac;
 static Autocomplete executable_param_ac;
 static Autocomplete intype_ac;
 static Autocomplete mood_ac;
+static Autocomplete ai_models_ac;
 static Autocomplete mood_type_ac;
 static Autocomplete strophe_ac;
 static Autocomplete strophe_sm_ac;
@@ -456,7 +465,11 @@ static Autocomplete* all_acs[] = {
     &vcard_togglable_param_ac,
     &vcard_address_type_ac,
     &force_encryption_ac,
-    &force_encryption_policy_ac
+    &force_encryption_policy_ac,
+    &ai_subcommands_ac,
+    &ai_set_subcommands_ac,
+    &ai_set_custom_subcommands_ac,
+    &ai_remove_subcommands_ac
 };
 
 static GHashTable* ac_funcs = NULL;
@@ -1169,6 +1182,27 @@ cmd_ac_init(void)
     autocomplete_add(correction_ac, "off");
     autocomplete_add(correction_ac, "char");
 
+    autocomplete_add_unsorted(ai_subcommands_ac, "set", FALSE);
+    autocomplete_add_unsorted(ai_subcommands_ac, "remove", FALSE);
+    autocomplete_add_unsorted(ai_subcommands_ac, "start", FALSE);
+    autocomplete_add_unsorted(ai_subcommands_ac, "clear", FALSE);
+    autocomplete_add_unsorted(ai_subcommands_ac, "providers", FALSE);
+    autocomplete_add_unsorted(ai_subcommands_ac, "switch", FALSE);
+    autocomplete_add_unsorted(ai_subcommands_ac, "models", FALSE);
+
+    autocomplete_add_unsorted(ai_set_subcommands_ac, "provider", FALSE);
+    autocomplete_add_unsorted(ai_set_subcommands_ac, "token", FALSE);
+    autocomplete_add_unsorted(ai_set_subcommands_ac, "default-provider", FALSE);
+    autocomplete_add_unsorted(ai_set_subcommands_ac, "default-model", FALSE);
+    autocomplete_add_unsorted(ai_set_subcommands_ac, "custom", FALSE);
+
+    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "tools", FALSE);
+    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "search", FALSE);
+    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "memory", FALSE);
+    autocomplete_add_unsorted(ai_set_custom_subcommands_ac, "plugins", FALSE);
+
+    autocomplete_add_unsorted(ai_remove_subcommands_ac, "provider", FALSE);
+
     autocomplete_add(avatar_ac, "set");
     autocomplete_add(avatar_ac, "disable");
     autocomplete_add(avatar_ac, "get");
@@ -1444,6 +1478,7 @@ cmd_ac_init(void)
     g_hash_table_insert(ac_funcs, "/wins", _wins_autocomplete);
     g_hash_table_insert(ac_funcs, "/wintitle", _wintitle_autocomplete);
     g_hash_table_insert(ac_funcs, "/force-encryption", _force_encryption_autocomplete);
+    g_hash_table_insert(ac_funcs, "/ai", _ai_autocomplete);
 }
 
 void
@@ -4450,4 +4485,167 @@ _force_encryption_autocomplete(ProfWin* window, const char* const input, gboolea
 
     result = autocomplete_param_with_ac(input, "/force-encryption", force_encryption_ac, TRUE, previous);
     return result;
-}
+}
+
+static char*
+_ai_autocomplete(ProfWin* window, const char* const input, gboolean previous)
+{
+    char* result = NULL;
+
+    /* Parse once for reuse - /ai <subcommand> [<arg1>] [<arg2>] */
+    gboolean parse_result = FALSE;
+    auto_gcharv gchar** args = parse_args(input, 1, 4, &parse_result);
+    gboolean space_at_end = g_str_has_suffix(input, " ");
+    int num_args = g_strv_length(args);
+
+    /* Top-level /ai <subcommand> autocomplete (e.g., /ai s<tab> -> /ai set) */
+    result = autocomplete_param_with_func(input, "/ai set provider", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai set token <provider> <token> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai set token", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai set default-provider <provider> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai set default-provider", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai set default-model <provider> <model> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai set default-model", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai set custom <provider> <setting> <value> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai set custom", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai set custom <provider> <setting> - autocomplete settings
+    /* args[0]="set", args[1]="custom", args[2]=provider (if typed), args[3]=setting (if typed) */
+    if (num_args == 3 && g_strcmp0(args[1], "custom") == 0) {
+        /* /ai set custom <provider> - check if provider is valid */
+        if (ai_get_provider(args[2])) {
+            /* Valid provider, try settings autocomplete */
+            result = autocomplete_param_with_ac(input, "/ai set custom ", ai_set_custom_subcommands_ac, TRUE, previous);
+            if (result) {
+                return result;
+            }
+        }
+    }
+    // /ai set <subcommand> - autocomplete subcommands
+    result = autocomplete_param_with_ac(input, "/ai set", ai_set_subcommands_ac, TRUE, previous);
+    if (result) {
+        return result;
+    }
+
+    // /ai remove provider <name> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai remove provider", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    result = autocomplete_param_with_ac(input, "/ai remove", ai_remove_subcommands_ac, TRUE, previous);
+    if (result) {
+        return result;
+    }
+
+    // /ai start [<provider>] [<model>] - use shared parse_args
+    if (parse_result && args && args[0] != NULL && g_strcmp0(args[0], "start") == 0) {
+        /* args[0]="start", args[1]=provider (if typed), args[2]=model (if typed) */
+        if (num_args == 1 || (num_args == 2 && !space_at_end)) {
+            result = autocomplete_param_with_func(input, "/ai start", ai_providers_find, previous, NULL);
+        } else {
+            /* /ai start <provider> <model> - model autocomplete */
+            result = _ai_model_autocomplete(window, input, previous, "/ai start ");
+        }
+        if (result) {
+            return result;
+        }
+    }
+
+    // /ai switch <provider> <model> - autocomplete model names for specified provider
+    result = _ai_model_autocomplete(window, input, previous, "/ai switch");
+    if (result) {
+        return result;
+    }
+
+    result = autocomplete_param_with_func(input, "/ai switch", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai switch <model> - autocomplete model names from current session's provider
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+    result = autocomplete_param_with_func(input, "/ai switch", ai_models_find, previous, aiwin);
+    if (result) {
+        return result;
+    }
+
+    // /ai models <provider> - autocomplete provider names
+    result = autocomplete_param_with_func(input, "/ai models", ai_providers_find, previous, NULL);
+    if (result) {
+        return result;
+    }
+
+    // /ai clear - no autocomplete
+    // /ai providers - no autocomplete
+
+    result = autocomplete_param_with_ac(input, "/ai", ai_subcommands_ac, FALSE, previous);
+
+    return result;
+}
+
+/**
+ * Autocomplete model names for /ai <cmd> <provider> <model> patterns.
+ * Extracts provider from input and provides model completions from that provider's cached models.
+ * Uses static ai_models_ac to preserve cycling state (last_found) across calls.
+ */
+static char*
+_ai_model_autocomplete(ProfWin* window, const char* const input, gboolean previous, const char* cmd_prefix)
+{
+    if (!g_str_has_prefix(input, cmd_prefix)) {
+        return NULL;
+    }
+
+    /* Extract provider name from input (after cmd_prefix) */
+    auto_gchar gchar* rest = g_strdup(input + strlen(cmd_prefix));
+    char* space = strchr(rest, ' ');
+    if (space) {
+        *space = '\0';
+    }
+
+    /* Look up the provider by name and get its models */
+    AIProvider* prov = ai_get_provider(rest);
+    if (!prov || !prov->models) {
+        return NULL;
+    }
+
+    if (!ai_models_ac) {
+        ai_models_ac = autocomplete_new();
+    }
+    /* Convert GList* to char** for autocomplete_update */
+    int model_count = g_list_length(prov->models);
+    char** model_array = g_new0(char*, model_count + 1);
+    GList* curr = prov->models;
+    int i = 0;
+    while (curr) {
+        model_array[i++] = curr->data;
+        curr = g_list_next(curr);
+    }
+
+    autocomplete_update(ai_models_ac, model_array);
+    g_free(model_array);
+
+    auto_gchar gchar* full_prefix = g_strdup_printf("%s%s", cmd_prefix, rest);
+
+    char* result = autocomplete_param_with_ac(input, full_prefix, ai_models_ac, TRUE, previous);
+    return result;
+}

src/command/cmd_defs.c

@@ -2787,6 +2787,71 @@ static const struct cmd_t command_defs[] = {
               "/force-encryption policy block")
     },
 
+    { CMD_PREAMBLE("/ai",
+                   parse_args, 0, 5, NULL)
+      CMD_SUBFUNCS(
+              { "set", cmd_ai_set },
+              { "remove", cmd_ai_remove },
+              { "start", cmd_ai_start },
+              { "clear", cmd_ai_clear },
+              { "providers", cmd_ai_providers },
+              { "switch", cmd_ai_switch },
+              { "models", cmd_ai_models })
+      CMD_MAINFUNC(cmd_ai)
+      CMD_TAGS(
+              CMD_TAG_CHAT)
+      CMD_SYN(
+              "/ai",
+              "/ai set provider <name> <url>",
+              "/ai set token <provider> <token>",
+              "/ai set default-provider <provider>",
+              "/ai set default-model <provider> <model>",
+              "/ai set custom <provider> <setting> <value>",
+              "/ai remove provider <name>",
+              "/ai providers",
+              "/ai start [<provider>] [<model>]",
+              "/ai switch <provider> [<model>]",
+              "/ai switch <model>",
+              "/ai models <provider>",
+              "/ai clear")
+      CMD_DESC(
+              "Interact with AI models via OpenAI-compatible APIs. "
+              "Supports multiple providers (openai, perplexity, custom). "
+              "Each provider has its own API key, endpoint, default model, and settings. "
+              "Chat history is maintained per session and not persisted locally.")
+      CMD_ARGS(
+              { "", "Display current AI settings and configured providers" },
+              { "set provider <name> <url>", "Add or update a provider with custom API endpoint" },
+              { "set token <provider> <token>", "Set API token for a provider (e.g., openai, perplexity)" },
+              { "set default-provider <provider>", "Set global default provider for /ai start" },
+              { "set default-model <provider> <model>", "Set default model for a provider" },
+              { "set custom <provider> <setting> <value>", "Set provider-level setting (e.g., tools, search)" },
+              { "remove provider <name>", "Remove a custom provider" },
+              { "providers", "List configured providers with full details" },
+              { "start [<provider>] [<model>]", "Start new AI chat (space-separated, uses defaults if omitted)" },
+              { "switch <provider> [<model>]", "Switch to different provider (and optionally model)" },
+              { "switch <model>", "Change model in current session (keeps provider)" },
+              { "models <provider>", "Fetch and display available models for provider" },
+              { "clear", "Clear current chat history" })
+      CMD_EXAMPLES(
+              "/ai",
+              "/ai set token openai sk-xxx",
+              "/ai set token perplexity pplx-xxx",
+              "/ai set provider custom https://my-api.com/v1/chat/completions",
+              "/ai set default-provider perplexity",
+              "/ai set default-model perplexity sonar",
+              "/ai set custom perplexity tools enabled",
+              "/ai remove provider custom",
+              "/ai start",
+              "/ai start perplexity",
+              "/ai start perplexity sonar",
+              "/ai start openai gpt-4o",
+              "/ai switch gpt-4o",
+              "/ai switch openai gpt-5.4-nano",
+              "/ai models perplexity",
+              "/ai clear")
+    },
+
     // NEXT-COMMAND (search helper)
 };
 

src/command/cmd_funcs.c

@@ -81,7 +81,6 @@
 #include "tools/bookmark_ignore.h"
 #include "tools/editor.h"
 #include "plugins/plugins.h"
-#include "ui/inputwin.h"
 #include "ui/ui.h"
 #include "ui/window_list.h"
 #include "xmpp/avatar.h"
@@ -117,6 +116,8 @@
 #include "tools/clipboard.h"
 #endif
 
+#include "ai/ai_client.h"
+
 #ifdef HAVE_PYTHON
 #include "plugins/python_plugins.h"
 #endif
@@ -8466,7 +8467,7 @@ _cmd_execute_default(ProfWin* window, const char* inp)
     }
 
     // handle non commands in non chat or plugin windows
-    if (window->type != WIN_CHAT && window->type != WIN_MUC && window->type != WIN_PRIVATE && window->type != WIN_PLUGIN && window->type != WIN_XML) {
+    if (window->type != WIN_CHAT && window->type != WIN_MUC && window->type != WIN_PRIVATE && window->type != WIN_PLUGIN && window->type != WIN_XML && window->type != WIN_AI) {
         cons_show("Unknown command: %s", inp);
         cons_alert(NULL);
         return TRUE;
@@ -8512,6 +8513,12 @@ _cmd_execute_default(ProfWin* window, const char* inp)
         connection_send_stanza(inp);
         break;
     }
+    case WIN_AI:
+    {
+        ProfAiWin* aiwin = (ProfAiWin*)window;
+        cl_ev_send_ai_msg(aiwin, inp, NULL);
+        break;
+    }
     default:
         break;
     }
@@ -10780,6 +10787,500 @@ cmd_vcard_save(ProfWin* window, const char* const command, gchar** args)
     return TRUE;
 }
 
+gboolean
+cmd_ai(ProfWin* window, const char* const command, gchar** args)
+{
+    if (args[0] == NULL) {
+        // Display current AI settings
+        cons_show("AI Chat - OpenAI-compatible API client");
+        cons_show("");
+
+        // List configured providers with full details
+        GList* providers = ai_list_providers();
+        cons_show("Configured providers:");
+        for (GList* curr = providers; curr; curr = g_list_next(curr)) {
+            AIProvider* provider = curr->data;
+            auto_gchar gchar* key = ai_get_provider_key(provider->name);
+            const gchar* default_model = ai_get_provider_default_model(provider->name);
+            cons_show("  %s", provider->name);
+            cons_show("    URL: %s", provider->api_url);
+            cons_show("    Key: %s", key ? "configured" : "NOT configured");
+            if (default_model) {
+                cons_show("    Default model: %s", default_model);
+            }
+            if (provider->models && g_list_length(provider->models) > 0) {
+                cons_show("    Cached models: %d", g_list_length(provider->models));
+            }
+            cons_show("");
+        }
+        g_list_free(providers);
+
+        cons_show("Use '/ai start' to begin a chat (uses default provider/model).");
+        cons_show("Use '/ai models <provider>' to fetch available models.");
+        cons_show("Available models: https://models.litellm.ai/");
+        return TRUE;
+    }
+
+    cons_bad_cmd_usage(command);
+    return TRUE;
+}
+
+gboolean
+cmd_ai_set(ProfWin* window, const char* const command, gchar** args)
+{
+    if (args[1] == NULL) {
+        cons_bad_cmd_usage(command);
+        return TRUE;
+    }
+
+    if (g_strcmp0(args[1], "provider") == 0) {
+        // /ai set provider <name> <url>
+        if (g_strv_length(args) < 4) {
+            cons_bad_cmd_usage(command);
+            return TRUE;
+        }
+        if (ai_add_provider(args[2], args[3], NULL)) {
+            cons_show("Provider '%s' configured with URL: %s", args[2], args[3]);
+        } else {
+            cons_show_error("Failed to configure provider '%s'.", args[2]);
+        }
+        cons_show("");
+        return TRUE;
+    } else if (g_strcmp0(args[1], "token") == 0) {
+        // /ai set token <provider> <token>
+        if (g_strv_length(args) < 4) {
+            cons_bad_cmd_usage(command);
+            return TRUE;
+        }
+        ai_set_provider_key(args[2], args[3]);
+        cons_show("API token set for provider: %s", args[2]);
+        cons_show("");
+        return TRUE;
+    } else if (g_strcmp0(args[1], "default-model") == 0) {
+        // /ai set default-model <provider> <model>
+        if (g_strv_length(args) < 4) {
+            cons_bad_cmd_usage(command);
+            return TRUE;
+        }
+        ai_set_provider_default_model(args[2], args[3]);
+        cons_show("Default model for provider '%s' set to: %s", args[2], args[3]);
+        cons_show("");
+        return TRUE;
+    } else if (g_strcmp0(args[1], "custom") == 0) {
+        // /ai set custom <provider> <setting> <value>
+        if (g_strv_length(args) < 5) {
+            cons_bad_cmd_usage(command);
+            return TRUE;
+        }
+        ai_set_provider_setting(args[2], args[3], args[4]);
+        cons_show("Setting '%s' for provider '%s' set to: %s", args[3], args[2], args[4]);
+        cons_show("");
+        return TRUE;
+    } else if (g_strcmp0(args[1], "default-provider") == 0) {
+        // /ai set default-provider <provider>
+        if (g_strv_length(args) < 3) {
+            cons_bad_cmd_usage(command);
+            return TRUE;
+        }
+        const gchar* provider_name = args[2];
+        AIProvider* provider = ai_get_provider(provider_name);
+        if (!provider) {
+            cons_show_error("Provider '%s' not found. Use '/ai set provider %s <url>' to add it.",
+                            provider_name, provider_name);
+            return TRUE;
+        }
+        prefs_set_string(PREF_AI_PROVIDER, provider_name);
+        cons_show("Default provider set to: %s", provider_name);
+        cons_show("");
+        return TRUE;
+    }
+
+    cons_bad_cmd_usage(command);
+    return TRUE;
+}
+
+gboolean
+cmd_ai_remove(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai remove provider <name>
+    if (g_strcmp0(args[1], "provider") != 0) {
+        cons_bad_cmd_usage(command);
+        return TRUE;
+    }
+
+    if (g_strv_length(args) < 3) {
+        cons_bad_cmd_usage(command);
+        return TRUE;
+    }
+
+    if (ai_remove_provider(args[2])) {
+        cons_show("Provider '%s' removed.", args[2]);
+    } else {
+        cons_show("Provider '%s' not found.", args[2]);
+    }
+    cons_show("");
+    return TRUE;
+}
+
+gboolean
+cmd_ai_start(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai start [<provider>] [<model>]
+    // Space-separated, no slash syntax
+    const gchar* provider_name = NULL;
+    const gchar* model = NULL;
+
+    if (g_strv_length(args) >= 2) {
+        provider_name = args[1];
+    }
+    if (g_strv_length(args) >= 3) {
+        model = args[2];
+    }
+
+    // Resolve defaults
+    auto_gchar gchar* owned_provider_name = NULL;
+    if (!provider_name) {
+        // Use default provider from preferences
+        auto_gchar gchar* default_provider = prefs_get_string(PREF_AI_PROVIDER);
+        if (default_provider && strlen(default_provider) > 0) {
+            provider_name = default_provider;
+        }
+    }
+    if (!provider_name) {
+        provider_name = "openai"; // Fallback
+    }
+
+    AIProvider* provider = ai_get_provider(provider_name);
+    if (!provider) {
+        cons_show_error("Provider '%s' not found. Use '/ai set provider %s <url>' to add it.",
+                        provider_name, provider_name);
+        return TRUE;
+    }
+
+    // Get model: explicit > provider default > hardcoded fallback
+    if (!model) {
+        model = ai_get_provider_default_model(provider_name);
+    }
+    if (!model) {
+        model = "gpt-4o"; // Fallback
+    }
+
+    // Check for API key
+    gchar* api_key = ai_get_provider_key(provider_name);
+    if (!api_key || strlen(api_key) == 0) {
+        cons_show_error("No API key set for provider '%s'. Use '/ai set token %s <key>' first.",
+                        provider_name, provider_name);
+        g_free(api_key);
+        return TRUE;
+    }
+    g_free(api_key);
+
+    // Create new AI session
+    AISession* session = ai_session_create(provider_name, model);
+    if (!session) {
+        log_error("[AI-CMD] Failed to create AI session");
+        cons_show_error("Failed to create AI session for %s/%s.", provider_name, model);
+        return TRUE;
+    }
+    log_debug("[AI-CMD] AI session created successfully");
+
+    // Create AI chat window
+    log_debug("[AI-CMD] Calling wins_new_ai()...");
+    ProfWin* ai_win = wins_new_ai(session);
+    if (!ai_win) {
+        log_error("[AI-CMD] wins_new_ai() returned NULL");
+        cons_show_error("Failed to create AI chat window.");
+        ai_session_unref(session);
+        return TRUE;
+    }
+    log_debug("[AI-CMD] wins_new_ai() returned successfully, window type: %d", ai_win->type);
+
+    // Add welcome message to the AI window
+    log_debug("[AI-CMD] Adding welcome messages...");
+    win_println(ai_win, THEME_DEFAULT, "-", "AI Chat: %s/%s", provider_name, model);
+    win_println(ai_win, THEME_DEFAULT, "-", "Type your message and press Enter to start a conversation.");
+    log_debug("[AI-CMD] Welcome messages added");
+
+    // Focus the new window
+    log_debug("[AI-CMD] Calling ui_focus_win()...");
+    ui_focus_win(ai_win);
+    log_debug("[AI-CMD] ui_focus_win() returned");
+
+    cons_show("Started AI chat: %s/%s", provider_name, model);
+    cons_show("");
+    log_debug("[AI-CMD] AI start command completed");
+
+    return TRUE;
+}
+
+gboolean
+cmd_ai_model(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai model <model>
+    if (args[1] == NULL) {
+        cons_bad_cmd_usage(command);
+        return TRUE;
+    }
+
+    const gchar* model = args[1];
+
+    // Get current AI window
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+    if (!aiwin) {
+        cons_show("No active AI chat window. Use '/ai start' first.");
+        return TRUE;
+    }
+
+    assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+
+    if (!aiwin->session) {
+        cons_show("No active session in this chat window.");
+        return TRUE;
+    }
+
+    ai_session_set_model(aiwin->session, model);
+    cons_show("Session model changed to: %s", model);
+    cons_show("");
+    return TRUE;
+}
+
+gboolean
+cmd_ai_switch(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai switch <provider> [<model>] - Change provider and optionally model
+    // /ai switch <model> - Change model only (keeps current provider)
+    // Modifies the existing session's provider and model instead of recreating it
+    if (g_strv_length(args) < 2) {
+        cons_bad_cmd_usage(command);
+        return TRUE;
+    }
+
+    // Get current AI window
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+    if (!aiwin) {
+        cons_show("No active AI chat window. Use '/ai start' first.");
+        return TRUE;
+    }
+
+    assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+
+    if (!aiwin->session) {
+        cons_show("No active session in this chat window.");
+        return TRUE;
+    }
+
+    const gchar* arg1 = args[1];
+    const gchar* arg2 = (g_strv_length(args) >= 3) ? args[2] : NULL;
+
+    const gchar* provider_name;
+    const gchar* model;
+    gboolean changed_provider = FALSE;
+
+    // Check if arg1 is a known provider
+    AIProvider* provider = ai_get_provider(arg1);
+    if (provider) {
+        // arg1 is a provider name
+        provider_name = arg1;
+        changed_provider = TRUE;
+
+        // Get model: arg2 > provider default > error
+        if (arg2) {
+            model = arg2;
+        } else {
+            model = ai_get_provider_default_model(provider_name);
+        }
+        if (!model) {
+            cons_show_error("No model specified and no default model set for provider '%s'.", provider_name);
+            cons_show("Use '/ai set default-model %s <model>' or '/ai switch %s <model>'.", provider_name, provider_name);
+            return TRUE;
+        }
+    } else {
+        // arg1 is a model name, keep current provider
+        provider_name = aiwin->session->provider_name;
+        model = arg1;
+    }
+
+    // Check for API key
+    auto_gchar gchar* api_key = ai_get_provider_key(provider_name);
+    if (!api_key || strlen(api_key) == 0) {
+        cons_show_error("No API key set for provider '%s'. Use '/ai set token %s <key>' first.",
+                        provider_name, provider_name);
+        return TRUE;
+    }
+
+    // Update the existing session's provider and model
+    if (changed_provider) {
+        AIProvider* new_provider = ai_get_provider(provider_name);
+        g_free(aiwin->session->provider_name);
+        aiwin->session->provider_name = g_strdup(provider_name);
+        ai_provider_unref(aiwin->session->provider);
+        aiwin->session->provider = new_provider;
+        aiwin->session->provider->ref_count++;
+    }
+    g_free(aiwin->session->model);
+    aiwin->session->model = g_strdup(model);
+    g_free(aiwin->session->api_key);
+    aiwin->session->api_key = g_strdup(api_key);
+
+    // Update window title
+    win_println((ProfWin*)aiwin, THEME_DEFAULT, "-", "AI Chat: %s/%s", provider_name, model);
+
+    cons_show("Switched to %s/%s", provider_name, model);
+    cons_show("");
+
+    return TRUE;
+}
+
+gboolean
+cmd_ai_models(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai models <provider> [--cached]
+    // Default: fetch fresh models from API
+    // --cached: display cached models (if available)
+    if (args[1] == NULL) {
+        cons_bad_cmd_usage(command);
+        return TRUE;
+    }
+
+    const gchar* provider_name = args[1];
+    gboolean use_cached = (g_strv_length(args) >= 3) && (g_strcmp0(args[2], "--cached") == 0);
+
+    AIProvider* provider = ai_get_provider(provider_name);
+    if (!provider) {
+        cons_show_error("Provider '%s' not found.", provider_name);
+        return TRUE;
+    }
+
+    if (use_cached) {
+        // Display cached models (if available)
+        if (!provider->models) {
+            cons_show("No cached models for provider '%s'. Use '/ai models %s' to fetch from API.", provider_name, provider_name);
+            return TRUE;
+        }
+        cons_show("Cached models for provider '%s':", provider_name);
+        GList* curr = provider->models;
+        while (curr) {
+            cons_show("  %s", (gchar*)curr->data);
+            curr = g_list_next(curr);
+        }
+        cons_show("");
+        cons_show("Use '/ai models %s' to fetch fresh models from the API.", provider_name);
+    } else {
+        // Default: fetch fresh models from API
+        ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+        ai_fetch_models(provider_name, aiwin);
+    }
+
+    return TRUE;
+}
+
+gboolean
+cmd_ai_clear(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai clear
+    ProfAiWin* aiwin = (window && window->type == WIN_AI) ? (ProfAiWin*)window : wins_get_ai();
+
+    if (aiwin) {
+        assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+        if (aiwin->session) {
+            ai_session_clear_history(aiwin->session);
+        }
+        cons_show("Chat history cleared.");
+    } else {
+        cons_show("No active AI chat window to clear.");
+    }
+    cons_show("");
+    return TRUE;
+}
+
+gboolean
+cmd_ai_correct(ProfWin* window, const char* const command, gchar** args)
+{
+    // /ai correct <message>
+    // Join all arguments from args[1] onwards to support multi-word prompts
+    auto_gchar gchar* prompt = g_strjoinv(" ", &args[1]);
+    if (prompt == NULL || strlen(prompt) == 0) {
+        cons_bad_cmd_usage(command);
+        return TRUE;
+    }
+
+    // Get current AI window
+    ProfAiWin* aiwin = wins_get_ai();
+    if (!aiwin) {
+        cons_show("No active AI chat window. Use '/ai start <provider>/<model>' first.");
+        return TRUE;
+    }
+
+    assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+
+    if (!aiwin->session) {
+        cons_show("No active session in this chat window.");
+        return TRUE;
+    }
+
+    // Get the last user message and replace it
+    GList* history = aiwin->session->history;
+    GList* last_user_msg = NULL;
+    for (GList* curr = history; curr; curr = g_list_next(curr)) {
+        AIMessage* msg = curr->data;
+        if (g_strcmp0(msg->role, "user") == 0) {
+            last_user_msg = curr;
+        }
+    }
+
+    if (!last_user_msg) {
+        cons_show("No user messages in this chat to correct.");
+        return TRUE;
+    }
+
+    // Replace the last user message
+    AIMessage* msg = last_user_msg->data;
+    g_free(msg->content);
+    msg->content = g_strdup(prompt);
+
+    // Resend the prompt
+    cons_show("Correcting message...");
+    ai_send_prompt(aiwin->session, prompt, aiwin);
+
+    return TRUE;
+}
+
+gboolean
+cmd_ai_providers(ProfWin* window, const char* const command, gchar** args)
+{
+    if (args[1] == NULL || g_strcmp0(args[1], "list") != 0) {
+        // List all available providers
+        cons_show("Available AI providers:");
+        cons_show("");
+        cons_show("  openai      - OpenAI API (https://api.openai.com)");
+        cons_show("  perplexity  - Perplexity API (https://api.perplexity.ai)");
+        cons_show("");
+        cons_show("Add custom providers with: /ai set provider <name> <url>");
+        return TRUE;
+    }
+
+    // List configured providers with key status
+    cons_show("Configured providers:");
+    cons_show("");
+
+    GList* providers = ai_list_providers();
+    for (GList* curr = providers; curr; curr = g_list_next(curr)) {
+        AIProvider* provider = curr->data;
+        gchar* key = ai_get_provider_key(provider->name);
+        cons_show("  %s", provider->name);
+        cons_show("    URL: %s", provider->api_url);
+        cons_show("    Key: %s", key ? "configured" : "NOT configured");
+        if (provider->org_id && strlen(provider->org_id) > 0) {
+            cons_show("    Org: %s", provider->org_id);
+        }
+        cons_show("");
+        g_free(key);
+    }
+    g_list_free(providers);
+
+    return TRUE;
+}
+
 gboolean
 cmd_force_encryption(ProfWin* window, const char* const command, gchar** args)
 {

src/command/cmd_funcs.h

@@ -166,6 +166,14 @@ gboolean cmd_console(ProfWin* window, const char* const command, gchar** args);
 gboolean cmd_command_list(ProfWin* window, const char* const command, gchar** args);
 gboolean cmd_command_exec(ProfWin* window, const char* const command, gchar** args);
 gboolean cmd_change_password(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai_set(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai_remove(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai_start(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai_clear(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai_providers(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai_switch(ProfWin* window, const char* const command, gchar** args);
+gboolean cmd_ai_models(ProfWin* window, const char* const command, gchar** args);
 
 gboolean cmd_plugins(ProfWin* window, const char* const command, gchar** args);
 gboolean cmd_plugins_sourcepath(ProfWin* window, const char* const command, gchar** args);

src/config/preferences.c

@@ -66,6 +66,7 @@
 #define PREF_GROUP_MUC           "muc"
 #define PREF_GROUP_PLUGINS       "plugins"
 #define PREF_GROUP_EXECUTABLES   "executables"
+#define PREF_GROUP_AI            "ai"
 
 #define INPBLOCK_DEFAULT 1000
 
@@ -1706,6 +1707,162 @@ _save_prefs(void)
     save_keyfile(&prefs_prof_keyfile);
 }
 
+/* ========================================================================
+ * AI Token Management
+ * ======================================================================== */
+
+gboolean
+prefs_ai_set_token(const char* const provider, const char* const token)
+{
+    if (!provider)
+        return FALSE;
+
+    if (!prefs)
+        return FALSE;
+
+    if (token) {
+        g_key_file_set_string(prefs, PREF_GROUP_AI, provider, token);
+        _save_prefs();
+        return TRUE;
+    } else {
+        return prefs_ai_remove_token(provider);
+    }
+}
+
+gboolean
+prefs_ai_remove_token(const char* const provider)
+{
+    if (!provider)
+        return FALSE;
+
+    if (!prefs)
+        return FALSE;
+
+    if (!g_key_file_has_key(prefs, PREF_GROUP_AI, provider, NULL)) {
+        return FALSE;
+    }
+
+    g_key_file_remove_key(prefs, PREF_GROUP_AI, provider, NULL);
+    _save_prefs();
+    return TRUE;
+}
+
+char*
+prefs_ai_get_token(const char* const provider)
+{
+    if (!provider || !prefs)
+        return NULL;
+
+    return g_key_file_get_string(prefs, PREF_GROUP_AI, provider, NULL);
+}
+
+GList*
+prefs_ai_list_tokens(void)
+{
+    if (!prefs || !g_key_file_has_group(prefs, PREF_GROUP_AI)) {
+        return NULL;
+    }
+
+    GList* result = NULL;
+    gsize len;
+    auto_gcharv gchar** keys = g_key_file_get_keys(prefs, PREF_GROUP_AI, &len, NULL);
+
+    for (gsize i = 0; i < len; i++) {
+        char* name = keys[i];
+        auto_gchar gchar* value = g_key_file_get_string(prefs, PREF_GROUP_AI, name, NULL);
+        if (value) {
+            result = g_list_append(result, g_strdup(name));
+        }
+    }
+
+    return result;
+}
+
+void
+prefs_free_ai_tokens(GList* tokens)
+{
+    if (tokens) {
+        g_list_free_full(tokens, g_free);
+    }
+}
+
+gboolean
+prefs_ai_set_models(const char* const provider, const gchar* const* models, gint count)
+{
+    if (!provider || count <= 0)
+        return FALSE;
+
+    if (!prefs)
+        return FALSE;
+
+    /* Build semicolon-separated model list */
+    GString* model_str = g_string_new("");
+    for (int i = 0; i < count; i++) {
+        if (i > 0) {
+            g_string_append_c(model_str, ';');
+        }
+        g_string_append(model_str, models[i]);
+    }
+
+    g_key_file_set_string(prefs, PREF_GROUP_AI, g_strconcat(provider, "_models", NULL), model_str->str);
+    g_string_free(model_str, TRUE);
+    _save_prefs();
+    return TRUE;
+}
+
+gboolean
+prefs_ai_remove_models(const char* const provider)
+{
+    if (!provider)
+        return FALSE;
+
+    if (!prefs)
+        return FALSE;
+
+    auto_gchar gchar* key = g_strconcat(provider, "_models", NULL);
+    if (!g_key_file_has_key(prefs, PREF_GROUP_AI, key, NULL)) {
+        return FALSE;
+    }
+
+    g_key_file_remove_key(prefs, PREF_GROUP_AI, key, NULL);
+    _save_prefs();
+    return TRUE;
+}
+
+GList*
+prefs_ai_get_models(const char* const provider)
+{
+    if (!provider || !prefs)
+        return NULL;
+
+    auto_gchar gchar* key = g_strconcat(provider, "_models", NULL);
+    if (!g_key_file_has_key(prefs, PREF_GROUP_AI, key, NULL)) {
+        return NULL;
+    }
+
+    auto_gchar gchar* model_str = g_key_file_get_string(prefs, PREF_GROUP_AI, key, NULL);
+    if (!model_str || strlen(model_str) == 0) {
+        return NULL;
+    }
+
+    GList* result = NULL;
+    gchar** models = g_strsplit(model_str, ";", -1);
+    for (int i = 0; models[i] != NULL; i++) {
+        result = g_list_append(result, g_strdup(models[i]));
+    }
+    g_strfreev(models);
+
+    return result;
+}
+
+void
+prefs_free_ai_models(GList* models)
+{
+    if (models) {
+        g_list_free_full(models, g_free);
+    }
+}
+
 // get the preference group for a specific preference
 // for example the PREF_BEEP setting ("beep" in .profrc, see _get_key) belongs
 // to the [ui] section.
@@ -1865,6 +2022,9 @@ _get_group(preference_t pref)
         return PREF_GROUP_OMEMO;
     case PREF_OX_LOG:
         return PREF_GROUP_OX;
+    case PREF_AI_PROVIDER:
+    case PREF_AI_API_KEY:
+        return PREF_GROUP_AI;
     default:
         return NULL;
     }
@@ -2142,6 +2302,10 @@ _get_key(preference_t pref)
         return "stamp.incoming";
     case PREF_OX_LOG:
         return "log";
+    case PREF_AI_PROVIDER:
+        return "provider";
+    case PREF_AI_API_KEY:
+        return "api_key";
     case PREF_MOOD:
         return "mood";
     case PREF_VCARD_PHOTO_CMD:
@@ -2319,6 +2483,10 @@ _get_default_string(preference_t pref)
         return "on";
     case PREF_FORCE_ENCRYPTION_MODE:
         return "resend-to-confirm";
+    case PREF_AI_PROVIDER:
+        return "openai";
+    case PREF_AI_API_KEY:
+        return "";
     default:
         return NULL;
     }

src/config/preferences.h

@@ -183,6 +183,9 @@ typedef enum {
     PREF_OX_LOG,
     PREF_MOOD,
     PREF_STROPHE_VERBOSITY,
+    PREF_AI_PROVIDER,
+    PREF_AI_API_KEY,
+    PREF_AI_DEFAULT_MODEL,
     PREF_STROPHE_SM_ENABLED,
     PREF_STROPHE_SM_RESEND,
     PREF_VCARD_PHOTO_CMD,
@@ -356,4 +359,17 @@ gboolean prefs_get_room_notify(const char* const roomjid);
 gboolean prefs_get_room_notify_mention(const char* const roomjid);
 gboolean prefs_get_room_notify_trigger(const char* const roomjid);
 
+/* AI token management */
+gboolean prefs_ai_set_token(const char* const provider, const char* const token);
+gboolean prefs_ai_remove_token(const char* const provider);
+char* prefs_ai_get_token(const char* const provider);
+GList* prefs_ai_list_tokens(void);
+void prefs_free_ai_tokens(GList* tokens);
+
+/* AI model cache management */
+gboolean prefs_ai_set_models(const char* const provider, const gchar* const* models, gint count);
+gboolean prefs_ai_remove_models(const char* const provider);
+GList* prefs_ai_get_models(const char* const provider);
+void prefs_free_ai_models(GList* models);
+
 #endif

src/event/client_events.c

@@ -37,8 +37,10 @@
 #include "config.h"
 
 #include <stdlib.h>
+#include <assert.h>
 #include <glib.h>
 
+#include "ai/ai_client.h"
 #include "log.h"
 #include "chatlog.h"
 #include "database.h"
@@ -47,7 +49,7 @@
 #include "event/common.h"
 #include "plugins/plugins.h"
 #include "ui/inputwin.h"
-#include "ui/window_list.h"
+#include "ui/window.h"
 #include "xmpp/chat_session.h"
 #include "xmpp/session.h"
 #include "xmpp/xmpp.h"
@@ -284,3 +286,29 @@ allow_unencrypted_message(ProfChatWin* chatwin, const char* const msg)
     win_println((ProfWin*)chatwin, THEME_ERROR, "-", "Message not sent: invalid encryption mode (%s). Use '/force-encryption policy resend-to-confirm'.", force_enc_mode);
     return FALSE;
 }
+
+void
+cl_ev_send_ai_msg(ProfAiWin* aiwin, const char* const message, const char* const id)
+{
+    if (!aiwin || !message) {
+        return;
+    }
+
+    assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+
+    if (!aiwin->session) {
+        log_error("[AI] AI session not initialized");
+        return;
+    }
+
+    // Snap viewport to bottom so the user's own message is visible even if
+    // they had scrolled up to read history; otherwise win_is_paged() in
+    // _win_printf would suppress the print.
+    win_move_to_end(&aiwin->window);
+
+    // Display user message in AI window.
+    win_print_outgoing(&aiwin->window, ">>", id, NULL, message);
+
+    // Send to AI provider.
+    ai_send_prompt(aiwin->session, message, aiwin);
+}

src/event/client_events.h

@@ -51,6 +51,7 @@ void cl_ev_send_msg(ProfChatWin* chatwin, const char* const msg, const char* con
 void cl_ev_send_muc_msg_corrected(ProfMucWin* mucwin, const char* const msg, const char* const oob_url, gboolean correct_last_msg);
 void cl_ev_send_muc_msg(ProfMucWin* mucwin, const char* const msg, const char* const oob_url);
 void cl_ev_send_priv_msg(ProfPrivateWin* privwin, const char* const msg, const char* const oob_url);
+void cl_ev_send_ai_msg(ProfAiWin* aiwin, const char* const message, const char* const id);
 
 // Checks if an unencrypted message can be sent based on encryption preferences.
 // Returns TRUE if allowed, FALSE if blocked.

src/profanity.c

@@ -69,6 +69,7 @@
 #include "xmpp/xmpp.h"
 #include "xmpp/muc.h"
 #include "xmpp/chat_session.h"
+#include "ai/ai_client.h"
 #include "xmpp/chat_state.h"
 #include "xmpp/contact.h"
 #include "xmpp/roster_list.h"
@@ -249,6 +250,7 @@ _init(char* log_level, char* config_file, char* log_file, char* theme_name)
     }
     session_init();
     cmd_init();
+    ai_client_init();
     log_info("Initialising contact list");
     muc_init();
     tlscerts_init();

src/ui/aiwin.c

@@ -0,0 +1,61 @@
+/*
+ * aiwin.c - AI Chat Window Management
+ *
+ * Provides functions for managing the AI chat window (ProfAiWin) in the
+ * profanity client. This includes retrieving window strings for identification,
+ * displaying AI/LLM responses in the chat view, and handling error messages
+ * from AI interactions.
+ *
+ * Key functions:
+ *   aiwin_get_string()       - Returns a descriptive string for the window
+ *   aiwin_display_response() - Displays an AI/LLM response and appends it
+ *                              to the conversation history
+ *   aiwin_display_error()    - Displays an error message from AI operations
+ *
+ * vim: expandtab:ts=4:sts=4:sw=4
+ */
+
+#include "config.h"
+
+#include <assert.h>
+
+#include "ai/ai_client.h"
+#include "log.h"
+#include "ui/ui.h"
+#include "ui/win_types.h"
+
+char*
+aiwin_get_string(ProfAiWin* win)
+{
+    assert(win->memcheck == PROFAIWIN_MEMCHECK);
+    return g_strdup_printf("AI Chat (%s: %s)", win->session->provider_name, win->session->model);
+}
+
+void
+aiwin_display_response(ProfAiWin* win, const char* response)
+{
+    log_debug("[AI-WIN] aiwin_display_response ENTER: win=%p, response='%s'", (void*)win, response);
+    assert(win->memcheck == PROFAIWIN_MEMCHECK);
+
+    if (!response) {
+        log_error("[AI-WIN] FAIL: null response");
+        return;
+    }
+
+    // Display AI response
+    win_println(&win->window, THEME_DEFAULT, "<< LLM:", "%s", response);
+    log_debug("[AI-WIN] Displayed AI response");
+}
+
+void
+aiwin_display_error(ProfAiWin* win, const char* error_msg)
+{
+    log_debug("[AI-WIN] aiwin_display_error ENTER: win=%p, error='%s'", (void*)win, error_msg);
+    assert(win->memcheck == PROFAIWIN_MEMCHECK);
+
+    const char* msg = error_msg ? error_msg : "Unknown error";
+    win_println(&win->window, THEME_ERROR, "[ERROR]", "%s", msg);
+
+    // Also show error in console so user sees it regardless of active window
+    cons_show_error("AI Error: %s", msg);
+}

src/ui/core.c

@@ -147,7 +147,7 @@ void
 ui_update(void)
 {
     ProfWin* current = wins_get_current();
-    if (current->layout->paged == 0) {
+    if (!win_is_paged(current)) {
         win_move_to_end(current);
     }
 

src/ui/titlebar.c

@@ -283,7 +283,7 @@ _show_attention(ProfWin* current, gboolean attention)
 static void
 _show_scrolled(ProfWin* current)
 {
-    if (current && current->layout->paged == 1) {
+    if (win_is_paged(current)) {
         int bracket_attrs = theme_attrs(THEME_TITLE_BRACKET);
         int scrolled_attrs = theme_attrs(THEME_TITLE_SCROLLED);
 

src/ui/ui.h

@@ -386,6 +386,8 @@ ProfWin* win_create_config(const char* const title, DataForm* form, ProfConfWinC
 ProfWin* win_create_private(const char* const fulljid);
 ProfWin* win_create_plugin(const char* const plugin_name, const char* const tag);
 ProfWin* win_create_vcard(vCard* vcard);
+ProfWin* win_create_ai(AISession* session);
+ProfWin* wins_new_ai(AISession* session);
 void win_update_virtual(ProfWin* window);
 void win_free(ProfWin* window);
 gboolean win_notify_remind(ProfWin* window);
@@ -445,4 +447,9 @@ void notify_invite(const char* const from, const char* const room, const char* c
 void notify(const char* const message, int timeout, const char* const category);
 void notify_subscription(const char* const from);
 
+/* AI window */
+char* aiwin_get_string(ProfAiWin* win);
+void aiwin_display_response(ProfAiWin* win, const char* response);
+void aiwin_display_error(ProfAiWin* win, const char* error_msg);
+
 #endif

src/ui/win_types.h

@@ -62,6 +62,7 @@
 #define PROFXMLWIN_MEMCHECK     87333463
 #define PROFPLUGINWIN_MEMCHECK  43434777
 #define PROFVCARDWIN_MEMCHECK   68947523
+#define PROFAIWIN_MEMCHECK      91827364
 
 typedef enum {
     FIELD_HIDDEN,
@@ -119,7 +120,6 @@ typedef struct prof_layout_t
     WINDOW* win;
     ProfBuff buffer;
     int y_pos;
-    int paged;
     int unread_msg;
 } ProfLayout;
 
@@ -144,19 +144,28 @@ typedef enum {
     WIN_PRIVATE,
     WIN_XML,
     WIN_PLUGIN,
-    WIN_VCARD
+    WIN_VCARD,
+    WIN_AI
 } win_type_t;
 
-typedef enum {
-    WIN_SCROLL_INNER,
-    WIN_SCROLL_REACHED_TOP,
-    WIN_SCROLL_REACHED_BOTTOM
-} win_scroll_state_t;
+// ScrollEdges tracks the two end-of-history conditions independently,
+// disentangling buffer-layout state (handled implicitly via y_pos) from
+// DB-content state. db_exhausted_above means a previous page-up fetch came
+// back empty: there is nothing older in the chat database, so the next
+// page-up should not re-issue the SQL/flatfile read. db_exhausted_below
+// is the analogous flag for newer rows. Both default to FALSE, are flipped
+// to TRUE on a respective DB_RESPONSE_EMPTY fetch, and are cleared by
+// scrolling in the opposite direction so a re-attempt happens after new
+// activity (e.g. MAM late delivery, /history switch).
+typedef struct {
+    gboolean db_exhausted_above;
+    gboolean db_exhausted_below;
+} ScrollEdges;
 
 typedef struct prof_win_t
 {
     win_type_t type;
-    win_scroll_state_t scroll_state;
+    ScrollEdges scroll_edges;
     ProfLayout* layout;
     Autocomplete urls_ac;
     Autocomplete quotes_ac;
@@ -258,4 +267,16 @@ typedef struct prof_vcard_win_t
     unsigned long memcheck;
 } ProfVcardWin;
 
+/* Forward declaration */
+typedef struct ai_session_t AISession;
+
+typedef struct prof_ai_win_t
+{
+    ProfWin window;
+    ProfBuff message_buffer;
+    GString* conversation_history;
+    AISession* session;
+    unsigned long memcheck;
+} ProfAiWin;
+
 #endif

src/ui/window.c

@@ -36,6 +36,7 @@
 
 #include "config.h"
 #include "database.h"
+#include "ui/win_types.h"
 #include "ui/window_list.h"
 
 #include <stdlib.h>
@@ -62,6 +63,7 @@
 #include "ui/screen.h"
 #include "xmpp/xmpp.h"
 #include "xmpp/roster_list.h"
+#include "ai/ai_client.h"
 
 static const char* LOADING_MESSAGE = "Loading older messages…";
 static const char* CONS_WIN_TITLE = "CProof. Type /help for help information.";
@@ -82,6 +84,26 @@ _check_subwin_width(int cols, int width)
     return cols <= 1 ? 1 : CLAMP(width, 1, cols - 1);
 }
 
+// Visible chat-area height in lines: stdscr minus the title bar (1), the
+// status bar (1), the input prompt area (1), and the separator (1).
+int
+win_page_space(void)
+{
+    return getmaxy(stdscr) - 4;
+}
+
+// True when the user has scrolled away from the live tail and there is
+// content below the visible viewport. Derived from y_pos and the current
+// height of the pad — no sticky flag, no possibility of staleness.
+gboolean
+win_is_paged(const ProfWin* window)
+{
+    if (!window || !window->layout || !window->layout->win)
+        return FALSE;
+    int total_rows = getcury(window->layout->win);
+    return (total_rows - window->layout->y_pos) > win_page_space();
+}
+
 int
 win_roster_cols(void)
 {
@@ -115,7 +137,6 @@ _win_create_simple_layout(void)
     wbkgd(layout->base.win, theme_attrs(THEME_TEXT));
     layout->base.buffer = buffer_create();
     layout->base.y_pos = 0;
-    layout->base.paged = 0;
     layout->base.unread_msg = 0;
     scrollok(layout->base.win, TRUE);
 
@@ -133,7 +154,6 @@ _win_create_split_layout(void)
     wbkgd(layout->base.win, theme_attrs(THEME_TEXT));
     layout->base.buffer = buffer_create();
     layout->base.y_pos = 0;
-    layout->base.paged = 0;
     layout->base.unread_msg = 0;
     scrollok(layout->base.win, TRUE);
     layout->subwin = NULL;
@@ -148,7 +168,7 @@ win_create_console(void)
 {
     ProfConsoleWin* new_win = malloc(sizeof(ProfConsoleWin));
     new_win->window.type = WIN_CONSOLE;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     new_win->window.layout = _win_create_split_layout();
 
     return &new_win->window;
@@ -160,7 +180,7 @@ win_create_chat(const char* const barejid)
     assert(barejid != NULL);
     ProfChatWin* new_win = malloc(sizeof(ProfChatWin));
     new_win->window.type = WIN_CHAT;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     new_win->window.layout = _win_create_simple_layout();
 
     new_win->barejid = strdup(barejid);
@@ -194,7 +214,7 @@ win_create_muc(const char* const roomjid)
     int cols = getmaxx(stdscr);
 
     new_win->window.type = WIN_MUC;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     ProfLayoutSplit* layout = malloc(sizeof(ProfLayoutSplit));
     layout->base.type = LAYOUT_SPLIT;
 
@@ -213,7 +233,6 @@ win_create_muc(const char* const roomjid)
     layout->memcheck = LAYOUT_SPLIT_MEMCHECK;
     layout->base.buffer = buffer_create();
     layout->base.y_pos = 0;
-    layout->base.paged = 0;
     layout->base.unread_msg = 0;
     scrollok(layout->base.win, TRUE);
     new_win->window.layout = (ProfLayout*)layout;
@@ -252,7 +271,7 @@ win_create_config(const char* const roomjid, DataForm* form, ProfConfWinCallback
     assert(form != NULL);
     ProfConfWin* new_win = malloc(sizeof(ProfConfWin));
     new_win->window.type = WIN_CONFIG;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     new_win->window.layout = _win_create_simple_layout();
     new_win->roomjid = strdup(roomjid);
     new_win->form = form;
@@ -271,7 +290,7 @@ win_create_private(const char* const fulljid)
     assert(fulljid != NULL);
     ProfPrivateWin* new_win = malloc(sizeof(ProfPrivateWin));
     new_win->window.type = WIN_PRIVATE;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     new_win->window.layout = _win_create_simple_layout();
     new_win->fulljid = strdup(fulljid);
     new_win->unread = 0;
@@ -288,7 +307,7 @@ win_create_xmlconsole(void)
 {
     ProfXMLWin* new_win = malloc(sizeof(ProfXMLWin));
     new_win->window.type = WIN_XML;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     new_win->window.layout = _win_create_simple_layout();
 
     new_win->memcheck = PROFXMLWIN_MEMCHECK;
@@ -303,7 +322,7 @@ win_create_plugin(const char* const plugin_name, const char* const tag)
     assert(tag != NULL);
     ProfPluginWin* new_win = malloc(sizeof(ProfPluginWin));
     new_win->window.type = WIN_PLUGIN;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     new_win->window.layout = _win_create_simple_layout();
 
     new_win->tag = strdup(tag);
@@ -320,7 +339,7 @@ win_create_vcard(vCard* vcard)
     assert(vcard != NULL);
     ProfVcardWin* new_win = malloc(sizeof(ProfVcardWin));
     new_win->window.type = WIN_VCARD;
-    new_win->window.scroll_state = WIN_SCROLL_INNER;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
     new_win->window.layout = _win_create_simple_layout();
 
     new_win->vcard = vcard;
@@ -329,6 +348,22 @@ win_create_vcard(vCard* vcard)
     return &new_win->window;
 }
 
+ProfWin*
+win_create_ai(AISession* session)
+{
+    ProfAiWin* new_win = g_new0(ProfAiWin, 1);
+    new_win->window.type = WIN_AI;
+    new_win->window.scroll_edges = (ScrollEdges){ FALSE, FALSE };
+    new_win->window.layout = _win_create_simple_layout();
+
+    new_win->message_buffer = buffer_create();
+    new_win->conversation_history = g_string_new("");
+    new_win->session = session ? ai_session_ref(session) : NULL;
+    new_win->memcheck = PROFAIWIN_MEMCHECK;
+
+    return &new_win->window;
+}
+
 gchar*
 win_get_title(ProfWin* window)
 {
@@ -407,6 +442,13 @@ win_get_title(ProfWin* window)
 
         return g_string_free(title, FALSE);
     }
+    case WIN_AI:
+    {
+        const ProfAiWin* aiwin = (ProfAiWin*)window;
+        assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+
+        return g_strdup_printf("AI Assistant (%s: %s)", aiwin->session->provider_name, aiwin->session->model);
+    }
     }
     assert(FALSE);
 }
@@ -454,6 +496,10 @@ win_get_tab_identifier(ProfWin* window)
     {
         return strdup("vcard");
     }
+    case WIN_AI:
+    {
+        return strdup("ai");
+    }
     }
     assert(FALSE);
 }
@@ -536,6 +582,12 @@ win_to_string(ProfWin* window)
         ProfVcardWin* vcardwin = (ProfVcardWin*)window;
         return vcardwin_get_string(vcardwin);
     }
+    case WIN_AI:
+    {
+        ProfAiWin* aiwin = (ProfAiWin*)window;
+        assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+        return aiwin_get_string(aiwin);
+    }
     }
     assert(FALSE);
 }
@@ -662,6 +714,17 @@ win_free(ProfWin* window)
         free(pluginwin->plugin_name);
         break;
     }
+    case WIN_AI:
+    {
+        ProfAiWin* aiwin = (ProfAiWin*)window;
+        assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+        buffer_free(aiwin->message_buffer);
+        g_string_free(aiwin->conversation_history, TRUE);
+        if (aiwin->session) {
+            ai_session_unref(aiwin->session);
+        }
+        break;
+    }
     default:
         break;
     }
@@ -676,11 +739,13 @@ win_page_up(ProfWin* window, int scroll_size)
     int* page_start = &(window->layout->y_pos);
     int page_start_initial = *page_start;
     // Size of the visible chat page
-    int page_space = getmaxy(stdscr) - 4;
+    int page_space = win_page_space();
     if (scroll_size == 0)
         scroll_size = page_space;
-    win_scroll_state_t* scroll_state = &window->scroll_state;
-    *scroll_state = (*scroll_state == WIN_SCROLL_REACHED_BOTTOM) ? WIN_SCROLL_INNER : *scroll_state;
+    ScrollEdges* edges = &window->scroll_edges;
+    // Going up means the bottom of the DB may have new content again; allow
+    // a re-fetch on the next page-down.
+    edges->db_exhausted_below = FALSE;
     *page_start -= scroll_size;
     gboolean has_scroll_past_buffer = *page_start < 0;
 
@@ -690,16 +755,18 @@ win_page_up(ProfWin* window, int scroll_size)
 
         gboolean is_still_fetching_mam = first_entry && (first_entry->theme_item == THEME_ROOMINFO && g_strcmp0(first_entry->message, LOADING_MESSAGE) == 0);
         if (!is_still_fetching_mam) {
-            // WIN_SCROLL_REACHED_TOP means that we reached top of DB and there is no need to refetch data from it
-            gboolean is_db_offset_jump_needed = false;
-            if (*scroll_state != WIN_SCROLL_REACHED_TOP) {
+            // db_exhausted_above suppresses further upward DB fetches; once
+            // a previous fetch returned empty, there is nothing older.
+            gboolean is_db_offset_jump_needed = FALSE;
+            if (!edges->db_exhausted_above) {
                 db_history_result_t db_response = chatwin_db_history(chatwin, NULL, NULL, TRUE);
                 is_db_offset_jump_needed = db_response == DB_RESPONSE_SUCCESS;
-                *scroll_state = db_response == DB_RESPONSE_EMPTY ? WIN_SCROLL_REACHED_TOP : WIN_SCROLL_INNER;
-                log_debug("Scroll state after DB history fetch: %s", *scroll_state ? "WIN_SCROLL_REACHED_TOP" : "WIN_SCROLL_INNER");
+                edges->db_exhausted_above = (db_response == DB_RESPONSE_EMPTY);
+                log_debug("Scroll edges after DB history fetch: above=%d below=%d",
+                          edges->db_exhausted_above, edges->db_exhausted_below);
             }
 
-            if (*scroll_state == WIN_SCROLL_REACHED_TOP) {
+            if (edges->db_exhausted_above) {
                 *page_start = 0;
                 if (prefs_get_boolean(PREF_MAM)) {
                     win_print_loading_history(window);
@@ -731,9 +798,7 @@ win_page_up(ProfWin* window, int scroll_size)
         win_update_virtual(window);
     }
 
-    // Update scrolling state
-    int total_rows = getcury(window->layout->win);
-    window->layout->paged = (total_rows) - *page_start > page_space;
+    // paged is derived on demand from y_pos / total_rows; nothing to set here.
 }
 
 void
@@ -742,13 +807,15 @@ win_page_down(ProfWin* window, int scroll_size)
     int total_rows = getcury(window->layout->win);
     int total_rows_with_unread = total_rows + window->layout->unread_msg;
     int* page_start = &(window->layout->y_pos);
-    int page_space = getmaxy(stdscr) - 4;
+    int page_space = win_page_space();
     int page_start_initial = *page_start;
 
     if (scroll_size == 0)
         scroll_size = page_space;
-    win_scroll_state_t* scroll_state = &window->scroll_state;
-    *scroll_state = (*scroll_state == WIN_SCROLL_REACHED_TOP) ? WIN_SCROLL_INNER : *scroll_state;
+    ScrollEdges* edges = &window->scroll_edges;
+    // Going down means the top of the DB may have new content again; allow
+    // a re-fetch on the next page-up (e.g. MAM late delivery).
+    edges->db_exhausted_above = FALSE;
 
     *page_start += scroll_size;
 
@@ -759,7 +826,7 @@ win_page_down(ProfWin* window, int scroll_size)
 
     if ((past_bottom || at_page_space_and_past_unread) && is_chat) {
         int bf_size = buffer_size(window->layout->buffer);
-        if (bf_size > 0 && *scroll_state != WIN_SCROLL_REACHED_BOTTOM) {
+        if (bf_size > 0 && !edges->db_exhausted_below) {
             // How many lines are left until end of the screen
             int current_offset = total_rows - *page_start;
             GDateTime* now = g_date_time_new_now_local();
@@ -768,7 +835,7 @@ win_page_down(ProfWin* window, int scroll_size)
             auto_gchar gchar* end_date = g_date_time_format_iso8601(now);
             db_history_result_t db_response = chatwin_db_history((ProfChatWin*)window, start, end_date, FALSE);
             if (db_response == DB_RESPONSE_EMPTY)
-                *scroll_state = WIN_SCROLL_REACHED_BOTTOM;
+                edges->db_exhausted_below = TRUE;
 
             // similar to page_up (see explanation there)
             // Get offset of the message that was the latest prior to loading messages from the DB
@@ -780,26 +847,22 @@ win_page_down(ProfWin* window, int scroll_size)
 
     total_rows = getcury(window->layout->win);
 
-    // near the end, but will display only part of the page space, move a bit back to show full page
-    if ((total_rows - *page_start) < page_space) {
-        *page_start = total_rows - page_space;
-        // went past end, show last page
-    } else if (*page_start >= total_rows) {
-        *page_start = total_rows - page_space - 1;
+    // Clamp to the last full page so the viewport never goes past the buffer
+    // and always shows a full page when one is available.
+    int last_page_start = total_rows > page_space ? total_rows - page_space : 0;
+    if (*page_start > last_page_start) {
+        *page_start = last_page_start;
     }
 
-    window->layout->paged = 1;
-
     // update only if position has changed
     if ((page_start_initial != *page_start) || window->layout->unread_msg) {
         win_update_virtual(window);
     }
 
-    /* Switch off page if no messages left to read.
-     * TODO: update buffer end handling to check messages just after last entry.
-     */
-    if (*scroll_state == WIN_SCROLL_REACHED_BOTTOM) {
-        window->layout->paged = 0;
+    // Once the user is back at the buffer's last page the unread badge no
+    // longer reflects anything they have not seen — clear it. paged itself
+    // is derived from y_pos so there is no flag to flip.
+    if (*page_start >= last_page_start) {
         window->layout->unread_msg = 0;
     }
 }
@@ -808,8 +871,7 @@ void
 win_sub_page_down(ProfWin* window)
 {
     if (window->layout->type == LAYOUT_SPLIT) {
-        int rows = getmaxy(stdscr);
-        int page_space = rows - 4;
+        int page_space = win_page_space();
         ProfLayoutSplit* split_layout = (ProfLayoutSplit*)window->layout;
         int sub_y = getcury(split_layout->subwin);
         int* sub_y_pos = &(split_layout->sub_y_pos);
@@ -832,8 +894,7 @@ void
 win_sub_page_up(ProfWin* window)
 {
     if (window->layout->type == LAYOUT_SPLIT) {
-        int rows = getmaxy(stdscr);
-        int page_space = rows - 4;
+        int page_space = win_page_space();
         ProfLayoutSplit* split_layout = (ProfLayoutSplit*)window->layout;
         int* sub_y_pos = &(split_layout->sub_y_pos);
 
@@ -860,7 +921,6 @@ win_clear(ProfWin* window)
     int y = getcury(window->layout->win);
     int* page_start = &(window->layout->y_pos);
     *page_start = y;
-    window->layout->paged = 1;
     window->layout->unread_msg = 0;
     win_update_virtual(window);
 }
@@ -970,14 +1030,12 @@ win_refresh_with_subwin(ProfWin* window)
 void
 win_move_to_end(ProfWin* window)
 {
-    window->layout->paged = 0;
     window->layout->unread_msg = 0;
 
-    int rows = getmaxy(stdscr);
     int y = getcury(window->layout->win);
-    int size = rows - 3;
+    int page_space = win_page_space();
 
-    window->layout->y_pos = y - (size - 1);
+    window->layout->y_pos = y - page_space;
     if (window->layout->y_pos < 0) {
         window->layout->y_pos = 0;
     }
@@ -1754,12 +1812,13 @@ win_newline(ProfWin* window)
 static void
 _win_printf(ProfWin* window, const char* show_char, int pad_indent, GDateTime* timestamp, int flags, theme_item_t theme_item, const char* const display_from, const char* const from_jid, const char* const message_id, const char* const message, ...)
 {
-
-    /* Prevent printing and buffer update when user is viewing message history [SCROLLING]*/
-    if (window->layout->paged && wins_is_current(window)) {
-        window->layout->unread_msg++;
-        return;
-    }
+    /* Append the message to the curses pad and the in-memory buffer
+     * unconditionally. When the user is scrolled up (paged), the new line
+     * lands on rows below the visible viewport so it does not disturb what
+     * they are reading; they encounter it naturally on page-down. The
+     * unread badge is bumped so the title bar still reflects new activity.
+     */
+    const gboolean is_paged_now = win_is_paged(window) && wins_is_current(window);
 
     if (timestamp == NULL) {
         timestamp = g_date_time_new_now_local();
@@ -1776,6 +1835,10 @@ _win_printf(ProfWin* window, const char* show_char, int pad_indent, GDateTime* t
     _win_print_internal(window, show_char, pad_indent, timestamp, flags, theme_item, display_from, msg, NULL);
     buffer_append(window->layout->buffer, show_char, pad_indent, timestamp, flags, theme_item, display_from, from_jid, msg, NULL, message_id, y_start_pos, getcury(window->layout->win));
 
+    if (is_paged_now) {
+        window->layout->unread_msg++;
+    }
+
     inp_nonblocking(TRUE);
     g_date_time_unref(timestamp);
 

src/ui/window.h

@@ -81,6 +81,8 @@ void win_redraw(ProfWin* window);
 void win_print_loading_history(ProfWin* window);
 int win_roster_cols(void);
 int win_occpuants_cols(void);
+int win_page_space(void);
+gboolean win_is_paged(const ProfWin* window);
 void win_sub_print(WINDOW* win, char* msg, gboolean newline, gboolean wrap, int indent);
 void win_sub_newline_lazy(WINDOW* win);
 void win_mark_received(ProfWin* window, const char* const id);

src/ui/window_list.c

@@ -44,9 +44,11 @@
 
 #include "common.h"
 #include "config/preferences.h"
+#include "log.h"
 #include "config/theme.h"
 #include "plugins/plugins.h"
 #include "ui/ui.h"
+#include "ui/window.h"
 #include "ui/window_list.h"
 #include "xmpp/xmpp.h"
 #include "xmpp/roster_list.h"
@@ -374,6 +376,8 @@ wins_set_current_by_num(int i)
                 status_bar_active(1, conswin->type, "console");
             }
         }
+    } else {
+        log_error("Window not found for index %d", i);
     }
 }
 
@@ -714,6 +718,20 @@ wins_new_vcard(vCard* vcard)
     return newwin;
 }
 
+ProfWin*
+wins_new_ai(AISession* session)
+{
+    int result = _wins_get_next_available_num(keys);
+    ProfWin* newwin = win_create_ai(session);
+    if (!newwin) {
+        return NULL;
+    }
+    _wins_htable_insert(windows, GINT_TO_POINTER(result), newwin);
+    autocomplete_add(wins_ac, "ai");
+    autocomplete_add(wins_close_ac, "ai");
+    return newwin;
+}
+
 gboolean
 wins_do_notify_remind(void)
 {
@@ -841,7 +859,7 @@ wins_get_prune_wins(void)
 
     while (curr) {
         ProfWin* window = curr->data;
-        if (win_unread(window) == 0 && window->type != WIN_MUC && window->type != WIN_CONFIG && window->type != WIN_XML && window->type != WIN_CONSOLE) {
+        if (win_unread(window) == 0 && window->type != WIN_MUC && window->type != WIN_CONFIG && window->type != WIN_XML && window->type != WIN_CONSOLE && window->type != WIN_AI) {
             result = g_slist_append(result, window);
         }
         curr = g_list_next(curr);
@@ -849,6 +867,45 @@ wins_get_prune_wins(void)
     return result;
 }
 
+ProfAiWin*
+wins_get_ai(void)
+{
+    GList* curr = values;
+
+    while (curr) {
+        ProfWin* window = curr->data;
+        if (window->type == WIN_AI) {
+            ProfAiWin* aiwin = (ProfAiWin*)window;
+            assert(aiwin->memcheck == PROFAIWIN_MEMCHECK);
+            return aiwin;
+        }
+        curr = g_list_next(curr);
+    }
+
+    return NULL;
+}
+
+gboolean
+wins_ai_exists(ProfAiWin* const aiwin)
+{
+    if (!aiwin) {
+        return FALSE;
+    }
+
+    GList* curr = values;
+    while (curr) {
+        ProfWin* window = curr->data;
+        if (window->type == WIN_AI) {
+            if ((ProfAiWin*)window == aiwin) {
+                return TRUE;
+            }
+        }
+        curr = g_list_next(curr);
+    }
+
+    return FALSE;
+}
+
 void
 wins_lost_connection(void)
 {

src/ui/window_list.h

@@ -63,6 +63,8 @@ ProfPrivateWin* wins_get_private(const char* const fulljid);
 ProfPluginWin* wins_get_plugin(const char* const tag);
 ProfXMLWin* wins_get_xmlconsole(void);
 ProfVcardWin* wins_get_vcard(void);
+ProfAiWin* wins_get_ai(void);
+gboolean wins_ai_exists(ProfAiWin* const aiwin);
 
 void wins_close_plugin(char* tag);
 

tests/unittests/test_ai_client.c

@@ -0,0 +1,869 @@
+#include "prof_cmocka.h"
+#include "common.h"
+#include "ai/ai_client.h"
+#include <stdlib.h>
+
+/* ========================================================================
+ * Setup/Teardown
+ * ======================================================================== */
+
+int
+ai_client_setup(void** state)
+{
+    ai_client_init();
+    return 0;
+}
+
+int
+ai_client_teardown(void** state)
+{
+    ai_client_shutdown();
+    return 0;
+}
+
+/* ========================================================================
+ * Provider Management Tests
+ * ======================================================================== */
+
+void
+test_ai_client_init(void** state)
+{
+    /* After init, default providers should exist */
+    AIProvider* openai = ai_get_provider("openai");
+    assert_non_null(openai);
+    assert_string_equal("openai", openai->name);
+    assert_string_equal("https://api.openai.com/", openai->api_url);
+
+    AIProvider* perplexity = ai_get_provider("perplexity");
+    assert_non_null(perplexity);
+    assert_string_equal("perplexity", perplexity->name);
+    assert_string_equal("https://api.perplexity.ai/", perplexity->api_url);
+}
+
+void
+test_ai_add_provider(void** state)
+{
+    /* Add a custom provider (hash table owns ref; caller gets non-owning pointer) */
+    AIProvider* provider = ai_add_provider("custom", "https://custom.api.com/v1", "my-org");
+    assert_non_null(provider);
+    assert_string_equal("custom", provider->name);
+    assert_string_equal("https://custom.api.com/v1", provider->api_url);
+    assert_string_equal("my-org", provider->org_id);
+
+    /* Update existing provider (returns ref; caller owns it) */
+    AIProvider* updated = ai_add_provider("custom", "https://new.api.com/v1", NULL);
+    assert_non_null(updated);
+    assert_string_equal("https://new.api.com/v1", updated->api_url);
+    assert_null(updated->org_id);
+
+    ai_provider_unref(updated);
+}
+
+void
+test_ai_remove_provider(void** state)
+{
+    /* Remove default provider should fail */
+    assert_false(ai_remove_provider("nonexistent"));
+
+    /* Add and remove custom provider */
+    ai_add_provider("temp", "https://temp.api.com/v1", NULL);
+    assert_true(ai_remove_provider("temp"));
+    assert_null(ai_get_provider("temp"));
+}
+
+void
+test_ai_list_providers(void** state)
+{
+    GList* providers = ai_list_providers();
+    assert_non_null(providers);
+    assert_int_equal(2, g_list_length(providers)); /* openai and perplexity */
+
+    /* Free list (ai_list_providers returns non-ref'd providers; caller must not unref) */
+    g_list_free(providers);
+
+    /* Add another provider */
+    ai_add_provider("test", "https://test.api.com/v1", NULL);
+    providers = ai_list_providers();
+    assert_int_equal(3, g_list_length(providers));
+
+    /* Free list */
+    g_list_free(providers);
+}
+
+/* ========================================================================
+ * API Key Tests
+ * ======================================================================== */
+
+void
+test_ai_set_provider_key(void** state)
+{
+    ai_set_provider_key("openai", "sk-test-key-123");
+    {
+        auto_gchar gchar* key = ai_get_provider_key("openai");
+        assert_non_null(key);
+        assert_string_equal("sk-test-key-123", key);
+    }
+
+    /* Update key */
+    ai_set_provider_key("openai", "sk-new-key-456");
+    {
+        auto_gchar gchar* key = ai_get_provider_key("openai");
+        assert_string_equal("sk-new-key-456", key);
+    }
+
+    /* Remove key */
+    ai_set_provider_key("openai", NULL);
+    {
+        auto_gchar gchar* key = ai_get_provider_key("openai");
+        assert_null(key);
+    }
+}
+
+void
+test_ai_get_provider_key(void** state)
+{
+    /* No key set initially */
+    {
+        auto_gchar gchar* key = ai_get_provider_key("openai");
+        assert_null(key);
+    }
+
+    /* Set and get key */
+    ai_set_provider_key("perplexity", "pplx-abc123");
+    {
+        auto_gchar gchar* key = ai_get_provider_key("perplexity");
+        assert_non_null(key);
+        assert_string_equal("pplx-abc123", key);
+    }
+
+    /* Wrong provider returns null */
+    {
+        auto_gchar gchar* key = ai_get_provider_key("openai");
+        assert_null(key);
+    }
+}
+
+/* ========================================================================
+ * Session Tests
+ * ======================================================================== */
+
+void
+test_ai_session_create(void** state)
+{
+    AISession* session = ai_session_create("openai", "gpt-4");
+    assert_non_null(session);
+    assert_string_equal("openai", session->provider_name);
+    assert_string_equal("gpt-4", session->model);
+    assert_null(session->api_key); /* No key set */
+
+    ai_session_unref(session);
+}
+
+void
+test_ai_session_ref_unref(void** state)
+{
+    AISession* session = ai_session_create("openai", "gpt-4");
+    assert_non_null(session);
+
+    /* Reference */
+    AISession* ref = ai_session_ref(session);
+    assert_true(ref == session);
+
+    /* Unreference twice */
+    ai_session_unref(session);
+    ai_session_unref(ref); /* Should free here */
+}
+
+void
+test_ai_session_add_message(void** state)
+{
+    AISession* session = ai_session_create("openai", "gpt-4");
+    assert_non_null(session);
+
+    ai_session_add_message(session, "user", "Hello");
+    ai_session_add_message(session, "assistant", "Hi there!");
+
+    assert_int_equal(2, g_list_length(session->history));
+
+    AIMessage* first = session->history->data;
+    assert_string_equal("user", first->role);
+    assert_string_equal("Hello", first->content);
+
+    AIMessage* second = g_list_next(session->history)->data;
+    assert_string_equal("assistant", second->role);
+    assert_string_equal("Hi there!", second->content);
+
+    ai_session_unref(session);
+}
+
+void
+test_ai_session_clear_history(void** state)
+{
+    AISession* session = ai_session_create("openai", "gpt-4");
+
+    ai_session_add_message(session, "user", "Message 1");
+    ai_session_add_message(session, "user", "Message 2");
+    ai_session_add_message(session, "assistant", "Response");
+
+    assert_int_equal(3, g_list_length(session->history));
+
+    ai_session_clear_history(session);
+    assert_int_equal(0, g_list_length(session->history));
+
+    ai_session_unref(session);
+}
+
+void
+test_ai_session_set_model(void** state)
+{
+    AISession* session = ai_session_create("openai", "gpt-4");
+    assert_string_equal("gpt-4", session->model);
+
+    ai_session_set_model(session, "gpt-3.5-turbo");
+    assert_string_equal("gpt-3.5-turbo", session->model);
+
+    ai_session_unref(session);
+}
+
+/* ========================================================================
+ * JSON Escape Tests
+ * ======================================================================== */
+
+void
+test_ai_json_escape(void** state)
+{
+    gchar* escaped = ai_json_escape("hello \"world\"");
+    assert_string_equal("hello \\\"world\\\"", escaped);
+    g_free(escaped);
+}
+
+void
+test_ai_json_escape_null(void** state)
+{
+    gchar* escaped = ai_json_escape(NULL);
+    assert_string_equal("", escaped);
+    g_free(escaped);
+}
+
+void
+test_ai_json_escape_empty(void** state)
+{
+    gchar* escaped = ai_json_escape("");
+    assert_string_equal("", escaped);
+    g_free(escaped);
+}
+
+void
+test_ai_json_escape_special_chars(void** state)
+{
+    gchar* escaped = ai_json_escape("line1\nline2\ttab\\backslash\"quote");
+    assert_string_equal("line1\\nline2\\ttab\\\\backslash\\\"quote", escaped);
+    g_free(escaped);
+}
+
+void
+test_ai_json_escape_percent_signs(void** state)
+{
+    /* Critical: % characters in content must be escaped for JSON, not treated as format specifiers */
+    gchar* escaped = ai_json_escape("100% complete with %s and %d format strings");
+    assert_string_equal("100% complete with %s and %d format strings", escaped);
+    g_free(escaped);
+}
+
+void
+test_ai_json_escape_backslash_quote(void** state)
+{
+    /* Test escaped quote handling */
+    gchar* escaped = ai_json_escape("He said \"hello\" and \\ goodbye");
+    assert_string_equal("He said \\\"hello\\\" and \\\\ goodbye", escaped);
+    g_free(escaped);
+}
+
+void
+test_ai_session_api_key_is_copied(void** state)
+{
+    /* Verify that session owns its own copy of the API key */
+    ai_set_provider_key("openai", "sk-test-key-123");
+
+    AISession* session = ai_session_create("openai", "gpt-4");
+    assert_non_null(session);
+    assert_string_equal("sk-test-key-123", session->api_key);
+
+    /* Remove the provider key - session should still have its copy */
+    ai_set_provider_key("openai", NULL);
+    assert_non_null(session->api_key);
+    assert_string_equal("sk-test-key-123", session->api_key);
+
+    ai_session_unref(session);
+}
+
+void
+test_ai_add_provider_update_existing(void** state)
+{
+    /* Add a provider (hash table owns ref) */
+    AIProvider* provider = ai_add_provider("custom", "https://first.api.com/v1", "org1");
+    assert_non_null(provider);
+    assert_string_equal("https://first.api.com/v1", provider->api_url);
+    assert_string_equal("org1", provider->org_id);
+
+    /* Update the same provider (returns ref) */
+    provider = ai_add_provider("custom", "https://second.api.com/v1", "org2");
+    assert_non_null(provider);
+    assert_string_equal("https://second.api.com/v1", provider->api_url);
+    assert_string_equal("org2", provider->org_id);
+    ai_provider_unref(provider);
+}
+
+void
+test_ai_add_provider_null_name_returns_null(void** state)
+{
+    assert_null(ai_add_provider(NULL, "https://api.com/v1", NULL));
+}
+
+void
+test_ai_add_provider_null_url_returns_null(void** state)
+{
+    assert_null(ai_add_provider("test", NULL, NULL));
+}
+
+void
+test_ai_session_create_null_provider_returns_null(void** state)
+{
+    assert_null(ai_session_create("nonexistent", "gpt-4"));
+}
+
+void
+test_ai_session_create_null_model_returns_null(void** state)
+{
+    assert_null(ai_session_create("openai", NULL));
+}
+
+void
+test_ai_session_api_key_null_when_no_key_set(void** state)
+{
+    /* openai has no key set by default */
+    AISession* session = ai_session_create("openai", "gpt-4");
+    assert_non_null(session);
+    assert_null(session->api_key);
+    ai_session_unref(session);
+}
+
+/* ========================================================================
+ * Provider Autocomplete Tests
+ * ======================================================================== */
+
+void
+test_ai_providers_find_forward(void** state)
+{
+    /* Test forward iteration - should return first match */
+    auto_gchar gchar* result = ai_providers_find("o", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+}
+
+void
+test_ai_providers_find_forward_perplexity(void** state)
+{
+    /* Test forward iteration for perplexity */
+    auto_gchar gchar* result = ai_providers_find("p", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("perplexity", result);
+}
+
+void
+test_ai_providers_find_forward_custom(void** state)
+{
+    /* Add a custom provider and test */
+    ai_add_provider("custom", "https://custom.api.com/v1", NULL);
+
+    auto_gchar gchar* result = ai_providers_find("c", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("custom", result);
+}
+
+void
+test_ai_providers_find_forward_no_match(void** state)
+{
+    /* Test no match */
+    auto_gchar gchar* result = ai_providers_find("z", FALSE, NULL);
+    assert_null(result);
+}
+
+void
+test_ai_providers_find_forward_partial_match(void** state)
+{
+    /* Test partial match - should return providers starting with "ope" */
+    auto_gchar gchar* result = ai_providers_find("ope", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+}
+
+void
+test_ai_providers_find_next(void** state)
+{
+    /* Test that stateless implementation returns same result each call */
+    auto_gchar gchar* result1 = ai_providers_find("o", FALSE, NULL);
+    assert_non_null(result1);
+    assert_string_equal("openai", result1);
+
+    /* Second call with same params returns same result (stateless) */
+    auto_gchar gchar* result2 = ai_providers_find("o", FALSE, NULL);
+    assert_non_null(result2);
+    assert_string_equal("openai", result2);
+}
+
+void
+test_ai_providers_find_previous(void** state)
+{
+    /* Test that previous=TRUE returns last match in list */
+    /* With only "openai" starting with "o", both FALSE and TRUE return same result */
+    auto_gchar gchar* result1 = ai_providers_find("o", FALSE, NULL);
+    assert_non_null(result1);
+    assert_string_equal("openai", result1);
+
+    /* previous=TRUE also returns "openai" (only one match, so first==last) */
+    auto_gchar gchar* result2 = ai_providers_find("o", TRUE, NULL);
+    assert_non_null(result2);
+    assert_string_equal("openai", result2);
+}
+
+void
+test_ai_providers_find_null_search_str(void** state)
+{
+    /* NULL search_str triggers cycling: returns first provider in list */
+    auto_gchar gchar* result = ai_providers_find(NULL, FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+}
+
+void
+test_ai_providers_find_empty_search_str(void** state)
+{
+    /* Empty search_str triggers cycling: returns first provider in list */
+    auto_gchar gchar* result = ai_providers_find("", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+}
+
+void
+test_ai_providers_find_case_insensitive(void** state)
+{
+    /* Test that matching is case-insensitive (via g_ascii_strdown) */
+    auto_gchar gchar* result = ai_providers_find("OPENAI", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+
+    result = ai_providers_find("OpenAI", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+
+    result = ai_providers_find("openai", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+}
+
+/* ========================================================================
+ * AI Autocomplete Integration Tests
+ * ======================================================================== */
+
+void
+test_ai_start_provider_autocomplete_only_on_exact(void** state)
+{
+    auto_gchar gchar* result = ai_providers_find("", FALSE, NULL);
+    assert_non_null(result);
+    assert_string_equal("openai", result);
+}
+
+void
+test_ai_models_find_null_session(void** state)
+{
+    auto_gchar gchar* result = ai_models_find("gpt", FALSE, NULL);
+    assert_null(result);
+}
+
+void
+test_ai_models_find_null_provider(void** state)
+{
+    ai_add_provider("temp", "https://temp.api.com/v1", NULL);
+    AISession* session = ai_session_create("temp", "gpt-4");
+    assert_non_null(session);
+    ai_session_unref(session);
+}
+
+void
+test_ai_providers_find_cycling(void** state)
+{
+    /* NULL search_str should cycle through providers */
+    auto_gchar gchar* result1 = ai_providers_find(NULL, FALSE, NULL);
+    assert_non_null(result1);
+
+    auto_gchar gchar* result2 = ai_providers_find(NULL, FALSE, NULL);
+    assert_non_null(result2);
+
+    /* Cycling: consecutive calls with NULL should return different providers */
+    assert_string_not_equal(result1, result2);
+}
+
+/* ========================================================================
+ * Provider Default Model and Settings Tests
+ * ======================================================================== */
+
+void
+test_ai_set_provider_default_model(void** state)
+{
+    /* Set default model for openai provider */
+    ai_set_provider_default_model("openai", "gpt-5");
+
+    /* Verify the model was set */
+    const gchar* model = ai_get_provider_default_model("openai");
+    assert_non_null(model);
+    assert_string_equal("gpt-5", model);
+
+    /* Update default model */
+    ai_set_provider_default_model("openai", "gpt-4o");
+    model = ai_get_provider_default_model("openai");
+    assert_non_null(model);
+    assert_string_equal("gpt-4o", model);
+
+    /* Set default model for perplexity */
+    ai_set_provider_default_model("perplexity", "sonar-pro");
+    model = ai_get_provider_default_model("perplexity");
+    assert_non_null(model);
+    assert_string_equal("sonar-pro", model);
+}
+
+void
+test_ai_get_provider_default_model(void** state)
+{
+    /* NULL provider returns NULL */
+    assert_null(ai_get_provider_default_model(NULL));
+
+    /* Non-existent provider returns NULL */
+    assert_null(ai_get_provider_default_model("nonexistent"));
+
+    /* Default providers may or may not have default models set initially */
+    /* After setting, they should return the model */
+    ai_set_provider_default_model("openai", "test-model");
+    assert_string_equal("test-model", ai_get_provider_default_model("openai"));
+
+    /* NULL model argument should be ignored (no change) */
+    ai_set_provider_default_model("openai", NULL);
+    /* After setting NULL, the model should still be "test-model" because
+     * ai_set_provider_default_model returns early on NULL model */
+    assert_string_equal("test-model", ai_get_provider_default_model("openai"));
+}
+
+void
+test_ai_set_provider_setting(void** state)
+{
+    /* NULL provider should be ignored */
+    ai_set_provider_setting(NULL, "tools", "enabled");
+
+    /* NULL setting should be ignored */
+    ai_set_provider_setting("openai", NULL, "enabled");
+
+    /* Non-existent provider should log warning but not crash */
+    ai_set_provider_setting("nonexistent", "tools", "enabled");
+
+    /* Set a setting for openai */
+    ai_set_provider_setting("openai", "tools", "enabled");
+    ai_set_provider_setting("openai", "search", "disabled");
+
+    /* Verify settings were set */
+    gchar* tools = ai_get_provider_setting("openai", "tools");
+    assert_non_null(tools);
+    assert_string_equal("enabled", tools);
+    g_free(tools);
+
+    gchar* search = ai_get_provider_setting("openai", "search");
+    assert_non_null(search);
+    assert_string_equal("disabled", search);
+    g_free(search);
+
+    /* NULL value removes the setting */
+    ai_set_provider_setting("openai", "tools", NULL);
+    tools = ai_get_provider_setting("openai", "tools");
+    assert_null(tools);
+
+    /* Setting that was never set returns NULL */
+    assert_null(ai_get_provider_setting("openai", "nonexistent_setting"));
+}
+
+void
+test_ai_get_provider_setting(void** state)
+{
+    /* NULL provider returns NULL */
+    assert_null(ai_get_provider_setting(NULL, "tools"));
+
+    /* NULL setting returns NULL */
+    assert_null(ai_get_provider_setting("openai", NULL));
+
+    /* Non-existent provider returns NULL */
+    assert_null(ai_get_provider_setting("nonexistent", "tools"));
+
+    /* Provider without settings returns NULL */
+    assert_null(ai_get_provider_setting("perplexity", "tools"));
+
+    /* Set and get setting */
+    ai_set_provider_setting("openai", "temperature", "0.7");
+    gchar* temp = ai_get_provider_setting("openai", "temperature");
+    assert_non_null(temp);
+    assert_string_equal("0.7", temp);
+    g_free(temp);
+
+    /* Setting value is a copy (caller must free) */
+    ai_set_provider_setting("openai", "max_tokens", "2048");
+    temp = ai_get_provider_setting("openai", "max_tokens");
+    assert_non_null(temp);
+    assert_string_equal("2048", temp);
+    g_free(temp);
+}
+
+/* ========================================================================
+ * Model Caching Tests
+ * ======================================================================== */
+
+void
+test_ai_models_are_fresh_initial(void** state)
+{
+    /* After init, models should be fresh (or at least not crash) */
+    /* The ai_client_init() loads models from prefs, which may be empty initially */
+    /* So we just verify the function works correctly */
+
+    /* NULL provider returns FALSE */
+    assert_false(ai_models_are_fresh(NULL));
+
+    /* Non-existent provider returns FALSE */
+    assert_false(ai_models_are_fresh("nonexistent"));
+
+    /* Default providers - check that function doesn't crash */
+    /* Freshness depends on whether models were loaded from prefs */
+    gboolean fresh_openai = ai_models_are_fresh("openai");
+    assert_true(fresh_openai == TRUE || fresh_openai == FALSE); /* Just verify no crash */
+
+    gboolean fresh_perplexity = ai_models_are_fresh("perplexity");
+    assert_true(fresh_perplexity == TRUE || fresh_perplexity == FALSE); /* Just verify no crash */
+}
+
+/* ========================================================================
+ * Model Parsing Tests
+ * ======================================================================== */
+
+void
+test_ai_parse_models_openai_format(void** state)
+{
+    /* Test parsing OpenAI-compatible API response format */
+    /* Format: {"object":"list","data":[{"id":"model1",...},...]} */
+    ai_client_init();
+
+    AIProvider* provider = ai_add_provider("test", "https://test.api.com/v1", NULL);
+
+    /* JSON response from Perplexity/OpenAI API */
+    const gchar* json = "{\"object\":\"list\","
+                        "\"data\":["
+                        "{\"id\":\"anthropic/claude-haiku-4-5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"anthropic/claude-opus-4-5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"openai/gpt-5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"google/gemini-3-flash-preview\",\"object\":\"model\",\"created\":0,\"owned_by\":\"google\"}"
+                        "]}";
+
+    ai_parse_models_from_json(provider, json);
+
+    /* Verify models were parsed correctly */
+    assert_int_equal(4, g_list_length(provider->models));
+
+    /* Check specific models */
+    GList* models = provider->models;
+    assert_string_equal("anthropic/claude-haiku-4-5", models->data);
+    models = g_list_next(models);
+    assert_string_equal("anthropic/claude-opus-4-5", models->data);
+    models = g_list_next(models);
+    assert_string_equal("openai/gpt-5", models->data);
+    models = g_list_next(models);
+    assert_string_equal("google/gemini-3-flash-preview", models->data);
+
+    ai_provider_unref(provider);
+    ai_client_shutdown();
+}
+
+void
+test_ai_parse_models_perplexity_format(void** state)
+{
+    /* Test parsing actual Perplexity API response with all models from curl test */
+    ai_client_init();
+
+    AIProvider* provider = ai_add_provider("perplexity", "https://api.perplexity.ai/", NULL);
+
+    const gchar* json = "{\"object\":\"list\","
+                        "\"data\":["
+                        "{\"id\":\"anthropic/claude-haiku-4-5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"anthropic/claude-opus-4-5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"anthropic/claude-opus-4-6\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"anthropic/claude-opus-4-7\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"anthropic/claude-sonnet-4-5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"anthropic/claude-sonnet-4-6\",\"object\":\"model\",\"created\":0,\"owned_by\":\"anthropic\"},"
+                        "{\"id\":\"google/gemini-3-flash-preview\",\"object\":\"model\",\"created\":0,\"owned_by\":\"google\"},"
+                        "{\"id\":\"google/gemini-3.1-pro-preview\",\"object\":\"model\",\"created\":0,\"owned_by\":\"google\"},"
+                        "{\"id\":\"nvidia/nemotron-3-super-120b-a12b\",\"object\":\"model\",\"created\":0,\"owned_by\":\"nvidia\"},"
+                        "{\"id\":\"openai/gpt-5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"openai/gpt-5-mini\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"openai/gpt-5.1\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"openai/gpt-5.2\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"openai/gpt-5.4\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"openai/gpt-5.4-mini\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"openai/gpt-5.4-nano\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"openai/gpt-5.5\",\"object\":\"model\",\"created\":0,\"owned_by\":\"openai\"},"
+                        "{\"id\":\"perplexity/sonar\",\"object\":\"model\",\"created\":0,\"owned_by\":\"perplexity\"},"
+                        "{\"id\":\"xai/grok-4-1-fast-non-reasoning\",\"object\":\"model\",\"created\":0,\"owned_by\":\"xai\"},"
+                        "{\"id\":\"xai/grok-4.20-multi-agent\",\"object\":\"model\",\"created\":0,\"owned_by\":\"xai\"},"
+                        "{\"id\":\"xai/grok-4.20-non-reasoning\",\"object\":\"model\",\"created\":0,\"owned_by\":\"xai\"},"
+                        "{\"id\":\"xai/grok-4.20-reasoning\",\"object\":\"model\",\"created\":0,\"owned_by\":\"xai\"},"
+                        "{\"id\":\"xai/grok-4.3\",\"object\":\"model\",\"created\":0,\"owned_by\":\"xai\"}"
+                        "]}";
+
+    ai_parse_models_from_json(provider, json);
+
+    /* Verify all 23 models were parsed correctly */
+    assert_int_equal(23, g_list_length(provider->models));
+
+    /* Verify NO field names or owned_by values are in the model list */
+    /* The bug was that "id", "object", "model", "created", "owned_by" and provider names
+     * like "anthropic", "google", "openai", "nvidia", "perplexity", "xai" were extracted */
+    GList* models = provider->models;
+    while (models) {
+        const gchar* model = (const gchar*)models->data;
+        /* These should never be model IDs */
+        assert_false(g_strcmp0(model, "id") == 0);
+        assert_false(g_strcmp0(model, "object") == 0);
+        assert_false(g_strcmp0(model, "model") == 0);
+        assert_false(g_strcmp0(model, "created") == 0);
+        assert_false(g_strcmp0(model, "owned_by") == 0);
+        assert_false(g_strcmp0(model, "list") == 0);
+        /* These are owned_by values, not model IDs */
+        assert_false(g_strcmp0(model, "anthropic") == 0);
+        assert_false(g_strcmp0(model, "google") == 0);
+        assert_false(g_strcmp0(model, "openai") == 0);
+        assert_false(g_strcmp0(model, "nvidia") == 0);
+        assert_false(g_strcmp0(model, "perplexity") == 0);
+        assert_false(g_strcmp0(model, "xai") == 0);
+        models = g_list_next(models);
+    }
+
+    /* Verify first and last model IDs */
+    models = provider->models;
+    assert_string_equal("anthropic/claude-haiku-4-5", models->data);
+    models = g_list_last(models);
+    assert_string_equal("xai/grok-4.3", models->data);
+
+    ai_provider_unref(provider);
+    ai_client_shutdown();
+}
+
+void
+test_ai_parse_models_array_format(void** state)
+{
+    /* Test parsing simple array format: ["model1", "model2", ...] */
+    ai_client_init();
+
+    AIProvider* provider = ai_add_provider("test", "https://test.api.com/v1", NULL);
+
+    const gchar* json = "[\"model1\", \"model2\", \"model3\"]";
+
+    ai_parse_models_from_json(provider, json);
+
+    assert_int_equal(3, g_list_length(provider->models));
+
+    GList* models = provider->models;
+    assert_string_equal("model1", models->data);
+    models = g_list_next(models);
+    assert_string_equal("model2", models->data);
+    models = g_list_next(models);
+    assert_string_equal("model3", models->data);
+
+    ai_provider_unref(provider);
+    ai_client_shutdown();
+}
+
+void
+test_ai_parse_models_empty_json(void** state)
+{
+    /* Test parsing empty/invalid JSON */
+    ai_client_init();
+
+    AIProvider* provider = ai_add_provider("test", "https://test.api.com/v1", NULL);
+
+    ai_parse_models_from_json(provider, "");
+    assert_null(provider->models);
+    assert_int_equal(0, g_list_length(provider->models));
+
+    ai_parse_models_from_json(provider, "{\"invalid\": true}");
+    assert_null(provider->models);
+    assert_int_equal(0, g_list_length(provider->models));
+
+    ai_provider_unref(provider);
+    ai_client_shutdown();
+}
+
+void
+test_ai_parse_models_null_handling(void** state)
+{
+    /* Test NULL handling */
+    ai_client_init();
+
+    AIProvider* provider = ai_add_provider("test", "https://test.api.com/v1", NULL);
+
+    /* NULL json should not crash */
+    ai_parse_models_from_json(provider, NULL);
+    assert_null(provider->models);
+
+    ai_provider_unref(provider);
+    ai_client_shutdown();
+}
+
+void
+test_ai_parse_models_escaped_quotes(void** state)
+{
+    /* Test parsing model IDs with escaped quotes */
+    ai_client_init();
+
+    AIProvider* provider = ai_add_provider("test", "https://test.api.com/v1", NULL);
+
+    const gchar* json = "{\"object\":\"list\","
+                        "\"data\":["
+                        "{\"id\":\"test/model\\\"with\\\"quotes\",\"object\":\"model\",\"created\":0,\"owned_by\":\"test\"}"
+                        "]}";
+
+    ai_parse_models_from_json(provider, json);
+
+    assert_int_equal(1, g_list_length(provider->models));
+    /* Model ID should have the escaped quotes handled */
+    GList* models = provider->models;
+    assert_non_null(models);
+
+    ai_provider_unref(provider);
+    ai_client_shutdown();
+}
+
+void
+test_ai_parse_models_with_whitespace(void** state)
+{
+    /* Test parsing JSON with whitespace after colons */
+    ai_client_init();
+
+    AIProvider* provider = ai_add_provider("test", "https://test.api.com/v1", NULL);
+
+    /* JSON with spaces after colons (common in formatted JSON) */
+    const gchar* json = "{ \"object\": \"list\", "
+                        "\"data\": [ "
+                        "{ \"id\": \"model-with-spaces\", \"object\": \"model\", \"created\": 0, \"owned_by\": \"test\" }"
+                        "]}";
+
+    ai_parse_models_from_json(provider, json);
+
+    assert_int_equal(1, g_list_length(provider->models));
+    GList* models = provider->models;
+    assert_string_equal("model-with-spaces", models->data);
+
+    ai_provider_unref(provider);
+    ai_client_shutdown();
+}

tests/unittests/test_ai_client.h

@@ -0,0 +1,62 @@
+/*
+ * test_ai_client.h - AI client unit test declarations
+ */
+
+int ai_client_setup(void** state);
+int ai_client_teardown(void** state);
+
+void test_ai_client_init(void** state);
+void test_ai_add_provider(void** state);
+void test_ai_remove_provider(void** state);
+void test_ai_list_providers(void** state);
+void test_ai_set_provider_key(void** state);
+void test_ai_get_provider_key(void** state);
+void test_ai_session_create(void** state);
+void test_ai_session_ref_unref(void** state);
+void test_ai_session_add_message(void** state);
+void test_ai_session_clear_history(void** state);
+void test_ai_session_set_model(void** state);
+void test_ai_json_escape(void** state);
+void test_ai_json_escape_null(void** state);
+void test_ai_json_escape_empty(void** state);
+void test_ai_json_escape_special_chars(void** state);
+void test_ai_json_escape_percent_signs(void** state);
+void test_ai_json_escape_backslash_quote(void** state);
+void test_ai_session_api_key_is_copied(void** state);
+void test_ai_add_provider_update_existing(void** state);
+void test_ai_add_provider_null_name_returns_null(void** state);
+void test_ai_add_provider_null_url_returns_null(void** state);
+void test_ai_session_create_null_provider_returns_null(void** state);
+void test_ai_session_create_null_model_returns_null(void** state);
+void test_ai_session_api_key_null_when_no_key_set(void** state);
+/* Provider autocomplete tests */
+void test_ai_providers_find_forward(void** state);
+void test_ai_providers_find_forward_perplexity(void** state);
+void test_ai_providers_find_forward_custom(void** state);
+void test_ai_providers_find_forward_no_match(void** state);
+void test_ai_providers_find_forward_partial_match(void** state);
+void test_ai_providers_find_next(void** state);
+void test_ai_providers_find_previous(void** state);
+void test_ai_providers_find_null_search_str(void** state);
+void test_ai_providers_find_empty_search_str(void** state);
+void test_ai_providers_find_case_insensitive(void** state);
+/* Provider default model and settings tests */
+void test_ai_set_provider_default_model(void** state);
+void test_ai_get_provider_default_model(void** state);
+void test_ai_set_provider_setting(void** state);
+void test_ai_get_provider_setting(void** state);
+/* Model caching tests */
+void test_ai_models_are_fresh_initial(void** state);
+/* Model parsing tests */
+void test_ai_parse_models_openai_format(void** state);
+void test_ai_parse_models_perplexity_format(void** state);
+void test_ai_parse_models_array_format(void** state);
+void test_ai_parse_models_empty_json(void** state);
+void test_ai_parse_models_null_handling(void** state);
+void test_ai_parse_models_escaped_quotes(void** state);
+void test_ai_parse_models_with_whitespace(void** state);
+/* AI autocomplete integration tests */
+void test_ai_start_provider_autocomplete_only_on_exact(void** state);
+void test_ai_models_find_null_session(void** state);
+void test_ai_models_find_null_provider(void** state);
+void test_ai_providers_find_cycling(void** state);

tests/unittests/ui/stub_ai.c

@@ -0,0 +1,41 @@
+/*
+ * stub_ai.c - Stubs for AI window functions
+ */
+
+#include "ui/window.h"
+#include "ai/ai_client.h"
+
+ProfWin*
+win_create_ai(AISession* session)
+{
+    /* Return NULL to simulate failure in unit tests */
+    (void)session;
+    return NULL;
+}
+
+void
+aiwin_display_response(ProfAiWin* win, const char* response)
+{
+    /* Stub: do nothing */
+    (void)win;
+    (void)response;
+}
+
+void
+aiwin_display_error(ProfAiWin* win, const char* error_msg)
+{
+    /* Stub: do nothing */
+    (void)win;
+    (void)error_msg;
+}
+
+void
+win_print_outgoing(ProfWin* window, const char* show_char, const char* const id, const char* const replace_id, const char* const message)
+{
+    /* Stub: do nothing */
+    (void)window;
+    (void)show_char;
+    (void)id;
+    (void)replace_id;
+    (void)message;
+}

tests/unittests/ui/stub_ui.c

@@ -1433,3 +1433,8 @@ cons_has_alerts(void)
 {
     return FALSE;
 }
+
+void
+win_move_to_end(ProfWin* window)
+{
+}

tests/unittests/unittests.c

@@ -36,6 +36,7 @@
 #include "test_form.h"
 #include "test_callbacks.h"
 #include "test_plugins_disco.h"
+#include "test_ai_client.h"
 #include "test_database_export.h"
 #include "test_database_stress.h"
 
@@ -659,6 +660,62 @@ main(int argc, char* argv[])
         cmocka_unit_test_setup_teardown(test_cmd_force_encryption_invalid_policy, load_preferences, close_preferences),
         cmocka_unit_test_setup_teardown(test_allow_unencrypted_message_invalid_mode, load_preferences, close_preferences),
 
+        // AI client tests
+        cmocka_unit_test_setup_teardown(test_ai_client_init, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_add_provider, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_remove_provider, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_list_providers, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_set_provider_key, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_get_provider_key, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_create, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_ref_unref, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_add_message, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_clear_history, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_set_model, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_api_key_is_copied, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_add_provider_update_existing, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_add_provider_null_name_returns_null, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_add_provider_null_url_returns_null, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_create_null_provider_returns_null, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_create_null_model_returns_null, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_session_api_key_null_when_no_key_set, ai_client_setup, ai_client_teardown),
+        /* Provider autocomplete tests */
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_forward, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_perplexity, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_custom, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_no_match, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_forward_partial_match, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_next, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_previous, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_null_search_str, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_empty_search_str, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_case_insensitive, ai_client_setup, ai_client_teardown),
+        /* Provider default model and settings tests */
+        cmocka_unit_test_setup_teardown(test_ai_set_provider_default_model, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_get_provider_default_model, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_set_provider_setting, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_get_provider_setting, ai_client_setup, ai_client_teardown),
+        /* Model caching tests */
+        cmocka_unit_test_setup_teardown(test_ai_models_are_fresh_initial, ai_client_setup, ai_client_teardown),
+        /* Model parsing tests */
+        cmocka_unit_test(test_ai_parse_models_openai_format),
+        cmocka_unit_test(test_ai_parse_models_perplexity_format),
+        cmocka_unit_test(test_ai_parse_models_array_format),
+        cmocka_unit_test(test_ai_parse_models_empty_json),
+        cmocka_unit_test(test_ai_parse_models_null_handling),
+        cmocka_unit_test(test_ai_parse_models_escaped_quotes),
+        cmocka_unit_test(test_ai_parse_models_with_whitespace),
+        /* AI autocomplete integration tests */
+        cmocka_unit_test_setup_teardown(test_ai_start_provider_autocomplete_only_on_exact, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_models_find_null_session, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_models_find_null_provider, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test_setup_teardown(test_ai_providers_find_cycling, ai_client_setup, ai_client_teardown),
+        cmocka_unit_test(test_ai_json_escape),
+        cmocka_unit_test(test_ai_json_escape_null),
+        cmocka_unit_test(test_ai_json_escape_empty),
+        cmocka_unit_test(test_ai_json_escape_special_chars),
+        cmocka_unit_test(test_ai_json_escape_percent_signs),
+        cmocka_unit_test(test_ai_json_escape_backslash_quote),
         // Flatfile export/import round-trip
         cmocka_unit_test(test_ff_roundtrip_simple_chat),
         cmocka_unit_test(test_ff_roundtrip_with_all_metadata),