<?php
if (!defined('ABSPATH')) exit;

class AIWEST_Canvas {
    const TEMPLATE_SLUG = 'aiwest-canvas.php';

    public static function init() {
        add_filter('theme_page_templates', [__CLASS__, 'register_template']);
        add_filter('template_include', [__CLASS__, 'template_include'], 99);
        add_filter('body_class', [__CLASS__, 'body_class']);
    }

    public static function register_template($templates) {
        $templates[self::TEMPLATE_SLUG] = 'AI Webmaster Studio Canvas';
        return $templates;
    }

    public static function is_canvas_page($post_id = 0) {
        $post_id = $post_id ?: get_queried_object_id();
        if (!$post_id) return false;

        $template = get_page_template_slug($post_id);
        if ($template === self::TEMPLATE_SLUG) return true;

        return get_post_meta($post_id, '_aiwest_canvas_enabled', true) === 'yes';
    }

    public static function template_include($template) {
        if (is_singular('page') && self::is_canvas_page()) {
            $canvas = AIWEST_PATH . 'templates/aiwest-canvas.php';
            if (file_exists($canvas)) {
                return $canvas;
            }
        }

        return $template;
    }

    public static function body_class($classes) {
        if (is_singular('page') && self::is_canvas_page()) {
            $classes[] = 'aiwest-canvas-active';
        }
        return $classes;
    }


    public static function clean_structural_shortcodes($post_id) {
        $post_id = intval($post_id);
        $post = get_post($post_id);
        if (!$post || !in_array($post->post_type, ['page', 'post'], true)) {
            return false;
        }

        $content = $post->post_content;
        $clean = preg_replace('/\[aiwest_header\s*\/?\]/i', '', $content);
        $clean = preg_replace('/\[aiwest_footer\s*\/?\]/i', '', $clean);

        if ($clean === $content) {
            return 'unchanged';
        }

        if (class_exists('AIWEST_Undo')) {
            AIWEST_Undo::snapshot($post_id, 'canvas_clean_shortcodes', __('Snapshot before removing duplicated AI Header/Footer shortcodes.', 'ai-webmaster-studio'));
        }

        $result = wp_update_post([
            'ID' => $post_id,
            'post_content' => $clean,
        ], true);

        if (is_wp_error($result)) {
            return $result;
        }

        return 'cleaned';
    }

    public static function enable_for_page($post_id) {
        $post_id = intval($post_id);
        if (!$post_id || get_post_type($post_id) !== 'page') {
            return false;
        }

        if (!self::is_canvas_page($post_id)) update_post_meta($post_id, '_aiwest_canvas_previous_template', get_page_template_slug($post_id) ?: 'default');
        update_post_meta($post_id, '_aiwest_canvas_enabled', 'yes');
        update_post_meta($post_id, '_wp_page_template', self::TEMPLATE_SLUG);
        return true;
    }

    public static function disable_for_page($post_id) {
        $post_id = intval($post_id);
        if (!$post_id || get_post_type($post_id) !== 'page') {
            return false;
        }

        delete_post_meta($post_id, '_aiwest_canvas_enabled');
        if (get_page_template_slug($post_id) === self::TEMPLATE_SLUG) {
            update_post_meta($post_id, '_wp_page_template', get_post_meta($post_id, '_aiwest_canvas_previous_template', true) ?: 'default');
            delete_post_meta($post_id, '_aiwest_canvas_previous_template');
        }
        return true;
    }
}

AIWEST_Canvas::init();