feat(ai): implement robust JSON model parsing

Rewrote internal JSON parsing to correctly handle whitespace, escaped
quotes, and strict field context extraction. This prevents incorrect
field names or provider names from being added to the model list.

Added `ai_parse_models_from_json` public API to facilitate testing.

Changed `/ai models` default behavior to always fetch fresh models.
Replaced `--refresh` flag with `--cached` to display local cache.

Added comprehensive unit tests covering OpenAI and Perplexity formats,
array format, empty/null JSON, escaped quotes, and whitespace handling.

tests/unittests/test_ai_client.c

@@ -644,3 +644,226 @@ test_ai_models_are_fresh_initial(void** state)
     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

@@ -47,6 +47,14 @@ 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);

tests/unittests/unittests.c

@@ -697,6 +697,14 @@ main(int argc, char* argv[])
         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),