/*
 * session.c
 * vim: expandtab:ts=4:sts=4:sw=4
 *
 * Copyright (C) 2012 - 2019 James Booth <boothj5@gmail.com>
 *
 * SPDX-License-Identifier: GPL-3.0-or-later WITH OpenSSL-exception
 */

#include "config.h"

#include <assert.h>
#include <string.h>
#include <stdlib.h>

#include "profanity.h"
#include "log.h"
#include "common.h"
#include "config/preferences.h"
#include "plugins/plugins.h"
#include "event/server_events.h"
#include "event/client_events.h"
#include "xmpp/bookmark.h"
#include "xmpp/blocking.h"
#include "xmpp/connection.h"
#include "xmpp/capabilities.h"
#include "xmpp/session.h"
#include "xmpp/iq.h"
#include "xmpp/message.h"
#include "xmpp/presence.h"
#include "xmpp/roster.h"
#include "xmpp/stanza.h"
#include "xmpp/xmpp.h"
#include "xmpp/muc.h"
#include "xmpp/chat_session.h"
#include "xmpp/jid.h"

#ifdef HAVE_OMEMO
#include "omemo/omemo.h"
#include "xmpp/omemo.h"
#endif

// for auto reconnect
static struct
{
    char* name;
    char* passwd;
} saved_account;

static struct session_details
{
    char* name;
    char* jid;
    char* passwd;
    char* altdomain;
    int port;
    char* tls_policy;
    char* auth_policy;
} saved_details;

typedef enum {
    ACTIVITY_ST_ACTIVE,
    ACTIVITY_ST_IDLE,
    ACTIVITY_ST_AWAY,
    ACTIVITY_ST_XA,
} activity_state_t;

static GTimer* reconnect_timer;
static activity_state_t activity_state;
static resource_presence_t saved_presence;
static char* saved_status;

static void _session_free_internals(void);
static void _session_free_saved_details(void);

static void
_session_shutdown(void)
{
    if (reconnect_timer) {
        g_timer_destroy(reconnect_timer);
        reconnect_timer = NULL;
    }
    _session_free_internals();

    chat_sessions_clear();
    presence_sub_requests_destroy();

    connection_shutdown();
    if (saved_status) {
        free(saved_status);
    }
}

void
session_init(void)
{
    log_info("Initialising XMPP");
    prof_add_shutdown_routine(_session_shutdown);
    connection_init();
    presence_sub_requests_init();
    caps_init();
}

jabber_conn_status_t
session_connect_with_account(const ProfAccount* const account)
{
    assert(account != NULL);

    log_info("Connecting using account: %s", account->name);

    _session_free_internals();

    // save account name and password for reconnect
    saved_account.name = strdup(account->name);
    saved_account.passwd = strdup(account->password);

    auto_char char* jid = NULL;
    if (account->resource) {
        auto_jid Jid* jidp = jid_create_from_bare_and_resource(account->jid, account->resource);
        jid = strdup(jid_fulljid_or_barejid(jidp));
    } else {
        jid = strdup(account->jid);
    }

    jabber_conn_status_t result = connection_connect(
        jid,
        account->password,
        account->server,
        account->port,
        account->tls_policy,
        account->auth_policy);

    return result;
}

static jabber_conn_status_t
_session_connect(struct session_details* details)
{
    return connection_connect(
        details->jid,
        details->passwd,
        details->altdomain,
        details->port,
        details->tls_policy,
        details->auth_policy);
}

jabber_conn_status_t
session_connect_with_details(const char* const jid, const char* const passwd, const char* const altdomain,
                             const int port, const char* const tls_policy, const char* const auth_policy)
{
    assert(jid != NULL);
    assert(passwd != NULL);

    _session_free_internals();

    // save details for reconnect, remember name for account creating on success
    saved_details.name = strdup(jid);
    saved_details.passwd = strdup(passwd);
    if (altdomain) {
        saved_details.altdomain = strdup(altdomain);
    } else {
        saved_details.altdomain = NULL;
    }
    if (port != 0) {
        saved_details.port = port;
    } else {
        saved_details.port = 0;
    }
    if (tls_policy) {
        saved_details.tls_policy = strdup(tls_policy);
    } else {
        saved_details.tls_policy = NULL;
    }
    if (auth_policy) {
        saved_details.auth_policy = strdup(auth_policy);
    } else {
        saved_details.auth_policy = NULL;
    }

    // use random string when no resourcepart in provided jid
    auto_jid Jid* jidp = jid_create(jid);
    if (jidp->resourcepart == NULL) {
        auto_gchar gchar* resource = jid_random_resource();
        jid_destroy(jidp);
        jidp = jid_create_from_bare_and_resource(jid, resource);
        saved_details.jid = strdup(jidp->fulljid);
    } else {
        saved_details.jid = strdup(jid);
    }

    // connect with fulljid
    log_info("Connecting without account, JID: %s", saved_details.jid);

    return _session_connect(&saved_details);
}

void
session_autoping_fail(void)
{
    log_debug("[CONNDBG] session_autoping_fail: autoping timeout, triggering lost connection");
    session_lost_connection();
}

void
session_disconnect(void)
{
    // if connected, send end stream and wait for response
    if (connection_get_status() == JABBER_CONNECTED) {
        log_info("Closing connection");

        plugins_on_disconnect(session_get_account_name(), connection_get_fulljid());

        accounts_set_last_activity(session_get_account_name());

        iq_handlers_clear();

        connection_disconnect();
        message_handlers_clear();

        connection_clear_data();
        chat_sessions_clear();
        presence_clear_sub_requests();
    }

    connection_set_disconnected();
}

void
session_process_events(void)
{
    int reconnect_sec;

    jabber_conn_status_t conn_status = connection_get_status();
    switch (conn_status) {
    case JABBER_CONNECTED:
    case JABBER_CONNECTING:
    case JABBER_RAW_CONNECTED:
    case JABBER_RAW_CONNECTING:
    case JABBER_DISCONNECTING:
        connection_check_events();
        break;
    case JABBER_DISCONNECTED:
        reconnect_sec = prefs_get_reconnect();
        if ((reconnect_sec != 0) && reconnect_timer) {
            int elapsed_sec = (int)g_timer_elapsed(reconnect_timer, NULL);
            if (elapsed_sec > reconnect_sec) {
                log_debug("[CONNDBG] session_process_events: auto-reconnect triggered after %d seconds (threshold=%d)",
                          elapsed_sec, reconnect_sec);
                session_reconnect_now();
            }
        }
        break;
    case JABBER_RECONNECT:
        log_debug("[CONNDBG] session_process_events: JABBER_RECONNECT state, calling session_reconnect_now");
        session_reconnect_now();
        break;
    default:
        break;
    }
}

const char*
session_get_account_name(void)
{
    return saved_account.name;
}

static gboolean
_receive_mood(xmpp_stanza_t* const stanza, void* const userdata)
{
    if (!prefs_get_boolean(PREF_MOOD)) {
        return TRUE;
    }

    const char* from = xmpp_stanza_get_from(stanza);
    xmpp_stanza_t* event = xmpp_stanza_get_child_by_name_and_ns(stanza, STANZA_NAME_EVENT, STANZA_NS_PUBSUB_EVENT);
    if (event) {
        xmpp_stanza_t* items = xmpp_stanza_get_child_by_name(event, STANZA_NAME_ITEMS);
        if (items) {
            xmpp_stanza_t* item = xmpp_stanza_get_child_by_name(items, STANZA_NAME_ITEM);
            if (item) {
                xmpp_stanza_t* mood = xmpp_stanza_get_child_by_name_and_ns(item, STANZA_NAME_MOOD, STANZA_NS_MOOD);
                if (mood) {
                    xmpp_stanza_t* c = xmpp_stanza_get_children(mood);
                    if (c) {
                        const char* m = xmpp_stanza_get_name(c);
                        xmpp_stanza_t* t = xmpp_stanza_get_child_by_name(mood, STANZA_NAME_TEXT);
                        if (t) {
                            auto_char char* text = xmpp_stanza_get_text(t);
                            cons_show("Mood from %s %s (%s)", from, m, text);
                        } else {
                            cons_show("Mood from %s %s", from, m);
                        }
                    }
                }
            }
        }
    }
    return TRUE;
}

void
session_login_success(gboolean secured)
{
    chat_sessions_init();

    message_handlers_init();
    presence_handlers_init();
    iq_handlers_init();

    // logged in with account
    if (saved_account.name) {
        log_debug("[CONNDBG] Connection handler: logged in with account name: %s", saved_account.name);
        sv_ev_login_account_success(saved_account.name, secured);

        // logged in without account, use details to create new account
    } else {
        log_debug("[CONNDBG] Connection handler: logged in with jid: %s", saved_details.name);
        accounts_add(saved_details.name, saved_details.altdomain, saved_details.port, saved_details.tls_policy, saved_details.auth_policy);
        accounts_set_jid(saved_details.name, saved_details.jid);

        saved_account.name = strdup(saved_details.name);
        saved_account.passwd = strdup(saved_details.passwd);

        _session_free_saved_details();
        sv_ev_login_account_success(saved_account.name, secured);
    }

    roster_request();
    bookmark_request();
    blocking_request();

    // items discovery
    connection_request_features();
    const char* domain = connection_get_domain();
    iq_disco_items_request_onconnect(domain);

    if (prefs_get_boolean(PREF_CARBONS)) {
        iq_enable_carbons();
    }

    if ((prefs_get_reconnect() != 0) && reconnect_timer) {
        g_timer_destroy(reconnect_timer);
        reconnect_timer = NULL;
    }

    message_pubsub_event_handler_add(STANZA_NS_MOOD, _receive_mood, NULL, NULL);
    if (prefs_get_boolean(PREF_MOOD)) {
        caps_add_feature(STANZA_NS_MOOD_NOTIFY);
    }
}

void
session_login_failed(void)
{
    if (reconnect_timer == NULL) {
        log_debug("[CONNDBG] Connection handler: No reconnect timer");
        sv_ev_failed_login();
        _session_free_internals();
    } else {
        log_debug("[CONNDBG] Connection handler: Restarting reconnect timer");
        if (prefs_get_reconnect() != 0) {
            g_timer_start(reconnect_timer);
        }
    }

    connection_clear_data();
    chat_sessions_clear();
    presence_clear_sub_requests();
}

void
session_lost_connection(void)
{
    log_debug("[CONNDBG] session_lost_connection: connection lost, reconnect_interval=%d",
              prefs_get_reconnect());
    /* this callback also clears all cached data */
    sv_ev_lost_connection();
    if (prefs_get_reconnect() != 0) {
        assert(reconnect_timer == NULL);
        reconnect_timer = g_timer_new();
        log_debug("[CONNDBG] session_lost_connection: reconnect timer started");
    } else {
        log_debug("[CONNDBG] session_lost_connection: auto-reconnect disabled, cleaning up");
        _session_free_internals();
    }
}

void
session_init_activity(void)
{
    activity_state = ACTIVITY_ST_ACTIVE;
    saved_status = NULL;
}

void
session_check_autoaway(void)
{
    jabber_conn_status_t conn_status = connection_get_status();
    if (conn_status != JABBER_CONNECTED) {
        return;
    }

    auto_gchar gchar* mode = prefs_get_string(PREF_AUTOAWAY_MODE);
    gboolean check = prefs_get_boolean(PREF_AUTOAWAY_CHECK);
    gint away_time = prefs_get_autoaway_time();
    gint xa_time = prefs_get_autoxa_time();
    unsigned long away_time_ms = away_time * 60000;
    unsigned long xa_time_ms = xa_time * 60000;

    const char* account = session_get_account_name();
    resource_presence_t curr_presence = accounts_get_last_presence(account);
    auto_char char* curr_status = accounts_get_last_status(account);

    unsigned long idle_ms = ui_get_idle_time();

    switch (activity_state) {
    case ACTIVITY_ST_ACTIVE:
        if (idle_ms >= away_time_ms) {
            if (g_strcmp0(mode, "away") == 0) {
                if ((curr_presence == RESOURCE_ONLINE) || (curr_presence == RESOURCE_CHAT) || (curr_presence == RESOURCE_DND)) {
                    activity_state = ACTIVITY_ST_AWAY;

                    // save current presence
                    saved_presence = curr_presence;
                    if (saved_status) {
                        free(saved_status);
                    }
                    if (curr_status) {
                        saved_status = strdup(curr_status);
                    } else {
                        saved_status = NULL;
                    }

                    // send away presence with last activity
                    auto_gchar gchar* message = prefs_get_string(PREF_AUTOAWAY_MESSAGE);
                    connection_set_presence_msg(message);
                    if (prefs_get_boolean(PREF_LASTACTIVITY)) {
                        cl_ev_presence_send(RESOURCE_AWAY, (int)(idle_ms / 1000));
                    } else {
                        cl_ev_presence_send(RESOURCE_AWAY, 0);
                    }

                    int pri = accounts_get_priority_for_presence_type(account, RESOURCE_AWAY);
                    if (message) {
                        cons_show("Idle for %d minutes, status set to away (priority %d), \"%s\".", away_time, pri, message);
                    } else {
                        cons_show("Idle for %d minutes, status set to away (priority %d).", away_time, pri);
                    }

                    title_bar_set_presence(CONTACT_AWAY);
                }
            } else if (g_strcmp0(mode, "idle") == 0) {
                activity_state = ACTIVITY_ST_IDLE;

                // send current presence with last activity
                connection_set_presence_msg(curr_status);
                cl_ev_presence_send(curr_presence, (int)(idle_ms / 1000));
            }
        }
        break;
    case ACTIVITY_ST_IDLE:
        if (check && (idle_ms < away_time_ms)) {
            activity_state = ACTIVITY_ST_ACTIVE;

            cons_show("No longer idle.");

            // send current presence without last activity
            connection_set_presence_msg(curr_status);
            cl_ev_presence_send(curr_presence, 0);
        }
        break;
    case ACTIVITY_ST_AWAY:
        if (xa_time_ms > 0 && (idle_ms >= xa_time_ms)) {
            activity_state = ACTIVITY_ST_XA;

            // send extended away presence with last activity
            auto_gchar gchar* message = prefs_get_string(PREF_AUTOXA_MESSAGE);
            connection_set_presence_msg(message);
            if (prefs_get_boolean(PREF_LASTACTIVITY)) {
                cl_ev_presence_send(RESOURCE_XA, (int)(idle_ms / 1000));
            } else {
                cl_ev_presence_send(RESOURCE_XA, 0);
            }

            int pri = accounts_get_priority_for_presence_type(account, RESOURCE_XA);
            if (message) {
                cons_show("Idle for %d minutes, status set to xa (priority %d), \"%s\".", xa_time, pri, message);
            } else {
                cons_show("Idle for %d minutes, status set to xa (priority %d).", xa_time, pri);
            }

            title_bar_set_presence(CONTACT_XA);
        } else if (check && (idle_ms < away_time_ms)) {
            activity_state = ACTIVITY_ST_ACTIVE;

            cons_show("No longer idle.");

            // send saved presence without last activity
            connection_set_presence_msg(saved_status);
            cl_ev_presence_send(saved_presence, 0);
            contact_presence_t contact_pres = contact_presence_from_resource_presence(saved_presence);
            title_bar_set_presence(contact_pres);
        }
        break;
    case ACTIVITY_ST_XA:
        if (check && (idle_ms < away_time_ms)) {
            activity_state = ACTIVITY_ST_ACTIVE;

            cons_show("No longer idle.");

            // send saved presence without last activity
            connection_set_presence_msg(saved_status);
            cl_ev_presence_send(saved_presence, 0);
            contact_presence_t contact_pres = contact_presence_from_resource_presence(saved_presence);
            title_bar_set_presence(contact_pres);
        }
        break;
    }
}

static struct
{
    gchar* altdomain;
    unsigned short altport;
} reconnect;

/* This takes ownership of `altdomain`, i.e. the caller must not
 * free the value after calling this function.
 */
void
session_reconnect(gchar* altdomain, unsigned short altport)
{
    reconnect.altdomain = altdomain;
    reconnect.altport = altport;
}

void
session_reconnect_now(void)
{
    // reconnect with account.
    if (saved_account.name) {
        ProfAccount* account = accounts_get_account(saved_account.name);
        if (account == NULL) {
            log_error("Unable to reconnect, account no longer exists: %s", saved_account.name);
            return;
        }

        auto_gchar gchar* jid = NULL;
        if (account->resource) {
            jid = create_fulljid(account->jid, account->resource);
        } else {
            jid = g_strdup(account->jid);
        }
        const char* server;
        unsigned short port;
        if (reconnect.altdomain) {
            server = reconnect.altdomain;
            port = reconnect.altport;
        } else {
            server = account->server;
            g_assert(account->port >= 0 && account->port <= UINT16_MAX);
            port = (unsigned short)account->port;
        }

        log_debug("Attempting reconnect with account %s", account->name);
        connection_connect(jid, saved_account.passwd, server, port, account->tls_policy, account->auth_policy);
        account_free(account);
    } else {
        _session_connect(&saved_details);
    }
    if (reconnect_timer)
        g_timer_start(reconnect_timer);
}

static void
_session_free_internals(void)
{
    FREE_SET_NULL(saved_account.name);
    FREE_SET_NULL(saved_account.passwd);
    GFREE_SET_NULL(reconnect.altdomain);
    _session_free_saved_details();
}

static void
_session_free_saved_details(void)
{
    FREE_SET_NULL(saved_details.name);
    FREE_SET_NULL(saved_details.jid);
    FREE_SET_NULL(saved_details.passwd);
    FREE_SET_NULL(saved_details.altdomain);
    FREE_SET_NULL(saved_details.tls_policy);
    FREE_SET_NULL(saved_details.auth_policy);
}