<?php

if (! defined('ABSPATH')) {
    exit;
}

/**
 * The Model tab: its data, the embedding model upgrade, and the notices about
 * an outdated or deprecated embedding model.
 */
class RSVL_Model_Admin
{
    /** The Model tab's data. */
    public function get_tab_data(bool $is_active): array
    {
        $settings    = RSVL_Settings::all();
        $provider_id = $settings['chat_provider'];
        $provider    = RSVL_Provider::get_provider($provider_id);
        $embedding   = RSVL_Settings_Page::get_current_embedding_provider();

        $provider_names = [];
        foreach (RSVL_Provider::get_all_providers() as $id => $provider_obj) {
            $provider_names[ $id ] = $provider_obj->get_name();
        }

        $embedder          = new RSVL_Embedder();
        $upgrade_available = $embedder->is_upgrade_available();

        return [
            'is_active'                   => $is_active,
            'providers'                   => $provider_names,
            'current_provider'            => $provider_id,
            'provider_connected'          => RSVL_Settings_Page::is_provider_connected($provider_id),
            'available_models'            => $provider ? $provider->get_available_models() : [],
            'current_model'               => $settings['chat_model'] ?? '',
            'embedding_provider'          => $embedding,
            'embedding_model'             => $embedder->get_model(),
            'embedding_connected'         => RSVL_Settings_Page::is_provider_connected($embedding),
            'api_keys_url'                => admin_url('options-connectors.php'),
            'embedding_upgrade_available' => $upgrade_available,
        ];
    }

    /**
     * What the Model tab shows of a save made in place (admin-model.js), given
     * the settings before and after it. See RSVL_Admin::ajax_save_settings().
     */
    public function saved_response(array $before, array $after): array
    {
        return [
            'embedding_provider' => $after['embedding_provider'],
            'embedding_model'    => $this->get_tab_data(true)['embedding_model'],
            'training_running'   => RSVL_Indexing_Status::is_running(),
            // The switch has started retraining everything: see RSVL_Admin::ajax_save_settings().
            'retraining' => RSVL_Settings::is_embedding_provider_switch($before['embedding_provider'], $after['embedding_provider']),
        ];
    }

    public function ajax_upgrade_embedding_model()
    {
        $embedder = new RSVL_Embedder();
        if (! $embedder->is_upgrade_available()) {
            wp_send_json_error(['message' => __('Already on the latest embedding model.', 'resolver-ai-chatbot')]);
        }

        // Check before switching the model setting: if the reindex below were
        // rejected by the lock after the switch, searches would run against
        // embeddings from the old model until a manual retrain.
        if (RSVL_Indexer::is_indexing_locked()) {
            wp_send_json_error(['message' => __('Training is already in progress. Please wait for it to finish before upgrading.', 'resolver-ai-chatbot')]);
        }

        $provider     = $embedder->get_provider();
        $latest_model = $embedder->get_latest_model();
        $setting_key  = 'embedding_model_' . $provider;

        resolver_update_setting($setting_key, $latest_model);

        $count = (new RSVL_Indexer())->start_full_reindex();

        if (false === $count) {
            wp_send_json_error(['message' => __('Training is already in progress. Please wait for it to finish, then retrain all pages to finish the model upgrade.', 'resolver-ai-chatbot')]);
        }

        wp_send_json_success([
            /* translators: %s: number of items being re-embedded. */
            'message' => sprintf(_n('Upgrading embedding model. Re-indexing %s item.', 'Upgrading embedding model. Re-indexing %s items.', $count, 'resolver-ai-chatbot'), number_format_i18n($count)),
            'total'   => $count,
        ]);
    }

    public function admin_notice_model_deprecation(): void
    {
        if (! current_user_can('manage_options')) {
            return;
        }

        $embedder = new RSVL_Embedder();
        $dep_date = $embedder->get_deprecation_date();

        if (! $dep_date) {
            return;
        }

        $model_url   = RSVL_Admin::tab_url('model');
        $is_past     = strtotime($dep_date) <= time();
        $notice_type = $is_past ? 'notice-error rsvl-notice' : 'notice-warning rsvl-notice';

        if ($is_past) {
            $message = __('Your current embedding model has been deprecated and the chatbot has been disabled.', 'resolver-ai-chatbot');
        } else {
            $message = __('Your current embedding model is being deprecated.', 'resolver-ai-chatbot');
        }

        printf(
            '<div class="notice %s"><p><strong>Resolver:</strong> %s <a href="%s">%s</a></p></div>',
            esc_attr($notice_type),
            esc_html($message),
            esc_url($model_url),
            esc_html__('Please update the embedding model now.', 'resolver-ai-chatbot')
        );
    }

    public function admin_notice_embedding_upgrade(): void
    {
        if (! current_user_can('manage_options')) {
            return;
        }

        $screen = get_current_screen();
        if (! $screen || ! RSVL_Admin::is_plugin_screen($screen->id)) {
            return;
        }

        $embedder = new RSVL_Embedder();
        if (! $embedder->is_upgrade_available()) {
            return;
        }

        // Deprecated models are handled by admin_notice_model_deprecation — don't double up.
        if ($embedder->get_deprecation_date()) {
            return;
        }

        $settings_url = RSVL_Admin::tab_url('model');

        printf(
            '<div class="notice notice-info"><p>%s <a href="%s">%s</a></p></div>',
            esc_html__('A newer embedding model is available for your provider.', 'resolver-ai-chatbot'),
            esc_url($settings_url),
            esc_html__('Upgrade embedding model', 'resolver-ai-chatbot')
        );
    }

    /** Register the AJAX endpoint and notices. */
    public static function register(): void
    {
        $controller = new self();
        add_action('admin_notices', [$controller, 'admin_notice_model_deprecation']);
        add_action('admin_notices', [$controller, 'admin_notice_embedding_upgrade']);

        RSVL_Ajax::register(RSVL_Ajax::admin_routes([
            'resolver_upgrade_embedding_model' => 'ajax_upgrade_embedding_model',
        ]), $controller);
    }
}