<?php

/**
 * ident_switch - Roundcube plugin for fast switching between accounts.
 *
 * Copyright (C) 2016-2022 Boris Gulay
 * Copyright (C) 2019      Christian Landvogt
 * Copyright (C) 2021      Gergely Papp
 * Copyright (C) 2022      Mickael
 * Copyright (C) 2026      Gecka
 *
 * Original code licensed under GPL-3.0+.
 * New contributions licensed under AGPL-3.0+.
 *
 * @url https://github.com/Gecka-apps/ident_switch
 */

require_once __DIR__ . '/lib/IdentSwitchPreconfig.php';
require_once __DIR__ . '/lib/IdentSwitchForm.php';
require_once __DIR__ . '/lib/IdentSwitchSwitcher.php';
require_once __DIR__ . '/lib/IdentSwitchChecker.php';

/**
 * Roundcube plugin for fast switching between multiple IMAP accounts.
 *
 * Allows users to configure and switch between multiple mail accounts
 * (including remote) within a single Roundcube session, with alias support.
 *
 * @url https://github.com/Gecka-apps/ident_switch
 */
class ident_switch extends rcube_plugin
{
    /** @var string Task regex: active on all tasks except login/logout. */
    public $task = '?(?!login|logout).*';

    /** @var string Database table name for this plugin. */
    public const TABLE = 'ident_switch';

    /** @var string Session variable suffix used to store/restore state. */
    public const MY_POSTFIX = '_iswitch';

    /** @var int Flag: account switching is enabled. */
    public const DB_ENABLED = 1;

    /** @var int Legacy flag: use TLS for IMAP. Read-only for backward compat; new records store scheme in host. */
    public const DB_SECURE_IMAP_TLS = 4;

    /** @var int SMTP authentication: use same credentials as IMAP. */
    public const SMTP_AUTH_IMAP = 1;

    /** @var int SMTP authentication: no authentication required. */
    public const SMTP_AUTH_NONE = 2;

    /** @var int SMTP authentication: use custom credentials. */
    public const SMTP_AUTH_CUSTOM = 3;

    /** @var int Sieve authentication: use same credentials as IMAP. */
    public const SIEVE_AUTH_IMAP = 1;

    /** @var int Sieve authentication: no authentication required. */
    public const SIEVE_AUTH_NONE = 2;

    /** @var int Sieve authentication: use custom credentials. */
    public const SIEVE_AUTH_CUSTOM = 3;

    /** @var int Notification checking: enabled. */
    public const NOTIFY_CHECK_ENABLED = 1;

    /** @var int Notification checking: disabled. */
    public const NOTIFY_CHECK_DISABLED = 0;

    private IdentSwitchForm $form;
    private IdentSwitchSwitcher $switcher;
    private IdentSwitchPreconfig $preconfig;
    private IdentSwitchChecker $checker;

    /**
     * Initialize plugin: register hooks, actions, and save default folder config.
     */
    public function init(): void
    {
        $this->form = new IdentSwitchForm($this);
        $this->switcher = new IdentSwitchSwitcher();
        $this->preconfig = new IdentSwitchPreconfig($this);
        $this->checker = new IdentSwitchChecker();

        $this->add_hook('startup', [$this, 'on_startup']);
        $this->add_hook('render_page', [$this, 'on_render_page']);
        $this->add_hook('refresh', [$this, 'on_refresh']);
        $this->add_hook('smtp_connect', [$this, 'on_smtp_connect']);
        $this->add_hook('managesieve_connect', [$this, 'on_managesieve_connect']);
        $this->add_hook('identity_form', [$this, 'on_identity_form']);
        $this->add_hook('identity_update', [$this, 'on_identity_update']);
        $this->add_hook('identity_create', [$this, 'on_identity_create']);
        $this->add_hook('identity_create_after', [$this, 'on_identity_create_after']);
        $this->add_hook('identity_delete', [$this, 'on_identity_delete']);
        $this->add_hook('template_object_composeheaders', [$this, 'on_template_object_composeheaders']);
        $this->add_hook('preferences_list', [$this, 'on_special_folders_form']);
        $this->add_hook('preferences_save', [$this, 'on_special_folders_update']);

        $this->register_action('plugin.ident_switch.switch', [$this, 'on_switch']);

        $this->load_config();

        $rc = rcmail::get_instance();
        foreach (rcube_storage::$folder_types as $type) {
            $key = $type . '_mbox_default' . self::MY_POSTFIX;
            if (empty($_SESSION[$key])) {
                $_SESSION[$key] = $rc->config->get($type . '_mbox');
            }
        }
    }

    /**
     * Handle startup hook: detect impersonation, disable caches, restore folder config.
     *
     * @param array $args Hook arguments containing 'task' and other startup data.
     * @return array Modified hook arguments.
     */
    public function on_startup(array $args): array
    {
        $rc = rcmail::get_instance();

        if (strcasecmp($rc->user->data['username'], $_SESSION['username']) !== 0) {
            // We are impersonating
            $rc->config->set('imap_cache', null);
            $rc->config->set('messages_cache', false);

            if ($args['task'] === 'mail') {
                $this->add_texts('localization/');
                $rc->config->set('create_default_folders', false);
            }
        }

        foreach (rcube_storage::$folder_types as $type) {
            $defaultKey = $type . '_mbox_default' . self::MY_POSTFIX;
            $otherKey = $type . '_mbox' . self::MY_POSTFIX;
            $val = $_SESSION[$otherKey] ?? $_SESSION[$defaultKey];
            $rc->config->set($type . '_mbox', $val);
        }

        return $args;
    }

    /**
     * Handle render_page hook: inject account switcher or settings form script.
     *
     * @param array $args Hook arguments containing page rendering data.
     * @return array Modified hook arguments.
     */
    public function on_render_page(array $args): array
    {
        $rc = rcmail::get_instance();

        match ($rc->task) {
            'mail' => $this->render_switch($rc, $args),
            'settings' => $this->include_script('ident_switch-form.js'),
            default => null,
        };

        if ($rc->task === 'mail') {
            $this->include_stylesheet('ident_switch.css');
        }

        return $args;
    }

    /**
     * Render the account switcher dropdown in the mail view.
     *
     * Queries the database for all enabled alternative accounts and generates
     * an HTML select element with an unread badge, injected into the page footer.
     *
     * @param rcmail $rc   Roundcube instance.
     * @param array  $args Hook arguments for page rendering.
     */
    private function render_switch(rcmail $rc, array $args): void
    {
        // Currently selected identity
        $iid_s = $_SESSION['iid' . self::MY_POSTFIX] ?? null;

        $iid = 0;
        if (is_int($iid_s)) {
            $iid = $iid_s;
        } elseif ($iid_s === '-1') {
            $iid = -1;
        } elseif (is_string($iid_s) && ctype_digit($iid_s)) {
            $iid = intval($iid_s);
        }

        $accNames = [$_SESSION['global_alias'] ?? $rc->user->data['username']];
        $accValues = [-1];
        $accSelected = -1;
        $iidMap = [0 => -1]; // primary account: iid 0 → select value -1

        // Get list of alternative accounts
        $sql = "SELECT "
            . "isw.id, isw.iid, isw.label, isw.username, ii.email"
            . " FROM"
            . " {$rc->db->table_name(self::TABLE)} isw"
            . " INNER JOIN {$rc->db->table_name('identities')} ii ON isw.iid=ii.identity_id"
            . " WHERE isw.user_id = ? AND isw.flags & ? > 0 AND isw.parent_id IS NULL";
        $qRec = $rc->db->query($sql, $rc->user->data['user_id'], self::DB_ENABLED);
        while ($r = $rc->db->fetch_assoc($qRec)) {
            $accValues[] = $r['id'];
            $iidMap[$r['iid']] = $r['id'];
            if ($iid === (int)$r['iid']) {
                $accSelected = $r['id'];
            }

            $lbl = $r['label'] ?: $r['username'] ?: $r['email'];
            $accNames[] = $lbl;
        }

        if (count($accValues) <= 1) {
            return;
        }

        $this->include_script('ident_switch-switch.js');

        // Pass config to JS environment
        $rc->output->set_env('ident_switch_iid_map', $iidMap);

        $select = new html_select([
            'id' => 'plugin-ident_switch-account',
            'style' => 'display: none; padding: 0;',
            'onchange' => 'plugin_switchIdent_switch(this.value);',
        ]);
        $select->add($accNames, $accValues);

        $html = '<span id="ident-switch-wrapper" class="ident-switch-wrapper">'
            . $select->show([$accSelected])
            . '<span id="ident-switch-badge" class="ident-switch-badge" style="display:none"></span>'
            . '</span>';

        $rc->output->add_footer($html);

        if (!$rc->config->get('ident_switch.check_mail', true)) {
            return;
        }

        // Run initial check and pass counts via env
        $this->checker->check_new_mail([]);
        $counts = $_SESSION['ident_switch_counts'] ?? [];
        $initialCounts = [];
        foreach ($counts as $cIid => $info) {
            $initialCounts[$cIid] = [
                'unseen' => $info['unseen'],
                'baseline' => $info['baseline'] ?? $info['unseen'],
            ];
        }
        $rc->output->set_env('ident_switch_initial_counts', $initialCounts);
    }

    /**
     * Handle refresh hook: check new mail on secondary identities.
     *
     * @param array $args Hook arguments (empty for refresh).
     * @return array Unmodified hook arguments.
     */
    public function on_refresh(array $args): array
    {
        $rc = rcmail::get_instance();
        if (!$rc->config->get('ident_switch.check_mail', true)) {
            return $args;
        }

        return $this->checker->check_new_mail($args);
    }

    /**
     * Handle smtp_connect hook: configure SMTP settings for the active account.
     *
     * @param array $args Hook arguments containing SMTP connection parameters.
     * @return array Modified hook arguments with updated SMTP settings.
     */
    public function on_smtp_connect(array $args): array
    {
        return $this->switcher->configure_smtp($args);
    }

    /**
     * Handle managesieve_connect hook: configure Sieve settings for the active account.
     *
     * @param array $args Hook arguments containing Sieve connection parameters.
     * @return array Modified hook arguments with updated Sieve settings.
     */
    public function on_managesieve_connect(array $args): array
    {
        return $this->switcher->configure_managesieve($args);
    }

    /**
     * Handle identity_form hook: add plugin-specific fields to the identity editor.
     *
     * @param array $args Hook arguments containing 'record' with identity data.
     * @return array Modified hook arguments with added form sections.
     */
    public function on_identity_form(array $args): array
    {
        return $this->form->on_identity_form($args, $this->preconfig);
    }

    /**
     * Handle identity_update hook: validate and save plugin fields on identity edit.
     *
     * @param array $args Hook arguments containing 'id' and 'record' with identity data.
     * @return array Modified hook arguments, with 'abort' set on validation failure.
     */
    public function on_identity_update(array $args): array
    {
        return $this->form->on_identity_update($args);
    }

    /**
     * Handle identity_create hook: validate plugin fields before identity creation.
     *
     * @param array $args Hook arguments containing 'record' with identity data.
     * @return array Modified hook arguments, with 'abort' set on validation failure.
     */
    public function on_identity_create(array $args): array
    {
        return $this->form->on_identity_create($args);
    }

    /**
     * Handle identity_create_after hook: persist plugin data after identity creation.
     *
     * @param array $args Hook arguments containing 'id' (new identity_id) and 'record'.
     * @return array Unmodified hook arguments.
     */
    public function on_identity_create_after(array $args): array
    {
        return $this->form->on_identity_create_after($args);
    }

    /**
     * Handle identity_delete hook: remove plugin data when an identity is deleted.
     *
     * @param array $args Hook arguments containing 'id' of the identity being deleted.
     * @return array Unmodified hook arguments.
     */
    public function on_identity_delete(array $args): array
    {
        return $this->form->on_identity_delete($args);
    }

    /**
     * Handle template_object_composeheaders hook: filter and fix identity selection.
     *
     * Restricts the From dropdown to identities belonging to the active account
     * (the account itself + its aliases). When impersonating, also pre-selects
     * the correct identity.
     *
     * @param array $args Hook arguments containing form element 'id'.
     */
    public function on_template_object_composeheaders(array $args): void
    {
        if ($args['id'] !== '_from') {
            return;
        }

        $rc = rcmail::get_instance();
        $userId = $rc->user->ID;
        $isImpersonating = strcasecmp($_SESSION['username'], $rc->user->data['username']) !== 0;

        // Pre-select the active identity when impersonating
        if ($isImpersonating) {
            if (isset($_SESSION['iid' . self::MY_POSTFIX])) {
                $iid = $_SESSION['iid' . self::MY_POSTFIX];
                $rc->output->add_script("plugin_switchIdent_fixIdent({$iid});", 'docready');
            } else {
                self::write_log('Special session variable with active identity ID not found.');
            }
        }

        // Compute allowed identity IDs for the From dropdown
        $iidSession = $_SESSION['iid' . self::MY_POSTFIX] ?? null;

        if ($isImpersonating && is_numeric($iidSession) && (int)$iidSession > 0) {
            // Switched to a secondary account: allow its identity + aliases
            $sql = 'SELECT id FROM ' . $rc->db->table_name(self::TABLE)
                . ' WHERE iid = ? AND user_id = ? AND parent_id IS NULL';
            $q = $rc->db->query($sql, (int)$iidSession, $userId);
            $r = $rc->db->fetch_assoc($q);

            if ($r) {
                $accountId = (int)$r['id'];
                $sql = 'SELECT iid FROM ' . $rc->db->table_name(self::TABLE)
                    . ' WHERE (id = ? OR parent_id = ?) AND user_id = ? AND flags & ? > 0';
                $q = $rc->db->query($sql, $accountId, $accountId, $userId, self::DB_ENABLED);
                $allowed = [];
                while ($row = $rc->db->fetch_assoc($q)) {
                    $allowed[] = (int)$row['iid'];
                }
                $rc->output->set_env('ident_switch_allowed_identities', $allowed);
            }
        } else {
            // Primary account: exclude identities belonging to enabled accounts/aliases
            $sql = 'SELECT iid FROM ' . $rc->db->table_name(self::TABLE)
                . ' WHERE user_id = ? AND flags & ? > 0';
            $q = $rc->db->query($sql, $userId, self::DB_ENABLED);
            $excluded = [];
            while ($row = $rc->db->fetch_assoc($q)) {
                $excluded[] = (int)$row['iid'];
            }

            if (!empty($excluded)) {
                $sql = 'SELECT identity_id FROM ' . $rc->db->table_name('identities')
                    . ' WHERE user_id = ? AND del = 0';
                $q = $rc->db->query($sql, $userId);
                $allowed = [];
                while ($row = $rc->db->fetch_assoc($q)) {
                    $iid = (int)$row['identity_id'];
                    if (!in_array($iid, $excluded)) {
                        $allowed[] = $iid;
                    }
                }
                $rc->output->set_env('ident_switch_allowed_identities', $allowed);
            }
        }
    }

    /**
     * Handle preferences_list hook: customize special folders form for remote accounts.
     *
     * @param array $args Hook arguments containing 'section' and 'blocks' with form data.
     * @return array Modified hook arguments with updated folder selections.
     */
    public function on_special_folders_form(array $args): array
    {
        return $this->switcher->get_special_folders_form($args);
    }

    /**
     * Handle preferences_save hook: persist special folder assignments for remote accounts.
     *
     * @param array $args Hook arguments containing 'section' and 'prefs' with folder data.
     * @return array Modified hook arguments, with 'abort' set to prevent default save.
     */
    public function on_special_folders_update(array $args): array
    {
        return $this->switcher->save_special_folders($args);
    }

    /**
     * Handle the account switch action (AJAX).
     */
    public function on_switch(): void
    {
        $this->switcher->switch_account();
    }

    /**
     * Trim a string, returning null if the result is empty.
     *
     * @param string|null $str Input string.
     * @return string|null Trimmed string or null if empty.
     */
    public static function ntrim(?string $str): ?string
    {
        if ($str === null) {
            return null;
        }

        $s = trim($str);
        return $s !== '' ? $s : null;
    }

    /**
     * Parse scheme prefix (ssl://, tls://) from a host string.
     *
     * @param string $host Host string, optionally prefixed with ssl:// or tls://.
     * @return array{scheme: string, host: string} Parsed scheme and bare host.
     */
    public static function parse_host_scheme(string $host): array
    {
        $lower = strtolower($host);
        if (str_starts_with($lower, 'ssl://')) {
            return ['scheme' => 'ssl', 'host' => substr($host, 6)];
        }
        if (str_starts_with($lower, 'tls://')) {
            return ['scheme' => 'tls', 'host' => substr($host, 6)];
        }
        return ['scheme' => '', 'host' => $host];
    }

    /**
     * Resolve username for an identity: use stored username or fall back to email.
     *
     * @param integer     $iid      Identity ID.
     * @param string|null $username Stored username (may be empty).
     * @return string Resolved username.
     */
    public static function resolve_username(int $iid, ?string $username): string
    {
        if (!empty($username)) {
            return $username;
        }

        $rc = rcmail::get_instance();
        $sql = 'SELECT email FROM ' . $rc->db->table_name('identities') . ' WHERE identity_id = ?';
        $q = $rc->db->query($sql, $iid);
        $r = $rc->db->fetch_assoc($q);
        return $r['email'] ?? '';
    }

    /**
     * Write a message to the plugin's log file.
     *
     * @param string $txt Log message.
     */
    public static function write_log(string $txt): void
    {
        rcmail::get_instance()->write_log('ident_switch', $txt);
    }

    /**
     * Write a debug message (only when ident_switch.debug is enabled).
     *
     * @param string $txt Log message.
     */
    public static function debug_log(string $txt): void
    {
        if (rcmail::get_instance()->config->get('ident_switch.debug', false)) {
            rcmail::get_instance()->write_log('ident_switch', '[DEBUG] ' . $txt);
        }
    }
}