<?php
/**
 * Bulk Conversion Class
 * 
 * Handles bulk conversion of pages and posts to static HTML.
 */

// Prevent direct access
if (!defined('ABSPATH')) {
    exit;
}

class WP_To_HTML_Bulk {
    
    /**
     * Single instance
     */
    private static $instance = null;
    
    /**
     * Batch size for processing
     */
    const BATCH_SIZE = 10;
    
    /**
     * Get singleton instance
     */
    public static function get_instance() {
        if (null === self::$instance) {
            self::$instance = new self();
        }
        return self::$instance;
    }
    
    /**
     * Constructor
     */
    private function __construct() {
        add_action('wp_ajax_wp_to_html_bulk_convert', array($this, 'ajax_bulk_convert'));
        add_action('wp_ajax_wp_to_html_clear_cache', array($this, 'ajax_clear_cache'));
        add_action('wp_ajax_wp_to_html_get_posts_count', array($this, 'ajax_get_posts_count'));
    }
    
    /**
     * AJAX handler for getting total posts count
     */
    public function ajax_get_posts_count() {
        check_ajax_referer('wp_to_html_bulk', 'nonce');
        
        if (!current_user_can('manage_options')) {
            wp_send_json_error(__('Permission denied', 'wp-to-html'));
        }
        
        $count = $this->get_eligible_posts_count();
        
        // Set initial status for bulk conversion
        WP_To_HTML_Cron::set_regeneration_status(array(
            'status'    => 'running',
            'source'    => 'settings_page',
            'started'   => time(),
            'total'     => $count,
            'processed' => 0,
            'converted' => 0,
            'skipped'   => 0,
            'errors'    => 0,
        ));
        
        wp_send_json_success(array(
            'total' => $count,
        ));
    }
    
    /**
     * AJAX handler for bulk conversion
     */
    public function ajax_bulk_convert() {
        check_ajax_referer('wp_to_html_bulk', 'nonce');
        
        if (!current_user_can('manage_options')) {
            wp_send_json_error(__('Permission denied', 'wp-to-html'));
        }
        
        $offset = isset($_POST['offset']) ? intval($_POST['offset']) : 0;
        
        $result = $this->process_batch($offset);
        
        // Get current status to accumulate totals
        $current_status = WP_To_HTML_Cron::get_regeneration_status();
        $converted = isset($current_status['converted']) ? $current_status['converted'] : 0;
        $skipped = isset($current_status['skipped']) ? $current_status['skipped'] : 0;
        $errors = isset($current_status['errors']) ? $current_status['errors'] : 0;
        $processed = isset($current_status['processed']) ? $current_status['processed'] : 0;
        
        // Update status with accumulated progress
        $new_status = array(
            'source'    => 'settings_page',
            'started'   => isset($current_status['started']) ? $current_status['started'] : time(),
            'total'     => $result['total'],
            'processed' => $processed + $result['processed'],
            'converted' => $converted + $result['converted'],
            'skipped'   => $skipped + $result['skipped'],
            'errors'    => $errors + $result['errors'],
        );
        
        if ($result['has_more']) {
            $new_status['status'] = 'running';
        } else {
            $new_status['status'] = 'complete';
            $new_status['completed'] = time();
        }
        
        WP_To_HTML_Cron::set_regeneration_status($new_status);
        
        wp_send_json_success($result);
    }
    
    /**
     * AJAX handler for clearing cache
     */
    public function ajax_clear_cache() {
        check_ajax_referer('wp_to_html_bulk', 'nonce');
        
        if (!current_user_can('manage_options')) {
            wp_send_json_error(__('Permission denied', 'wp-to-html'));
        }
        
        $generator = WP_To_HTML_Generator::get_instance();
        $generator->clear_all_cache();
        
        wp_send_json_success(array(
            'message' => __('Cache cleared successfully', 'wp-to-html'),
        ));
    }
    
    /**
     * Get count of eligible posts
     */
    private function get_eligible_posts_count() {
        $post_types = $this->get_eligible_post_types();
        
        $args = array(
            'post_type' => $post_types,
            'post_status' => 'publish',
            'posts_per_page' => -1,
            'fields' => 'ids',
        );
        
        $query = new WP_Query($args);
        
        return $query->post_count;
    }
    
    /**
     * Process a batch of posts
     */
    private function process_batch($offset) {
        $post_types = $this->get_eligible_post_types();
        
        $args = array(
            'post_type' => $post_types,
            'post_status' => 'publish',
            'posts_per_page' => self::BATCH_SIZE,
            'offset' => $offset,
            'orderby' => 'ID',
            'order' => 'ASC',
        );
        
        $query = new WP_Query($args);
        $generator = WP_To_HTML_Generator::get_instance();
        
        $results = array(
            'processed' => 0,
            'converted' => 0,
            'skipped' => 0,
            'errors' => 0,
            'details' => array(),
            'has_more' => false,
            'next_offset' => $offset + self::BATCH_SIZE,
        );
        
        if ($query->have_posts()) {
            while ($query->have_posts()) {
                $query->the_post();
                $post_id = get_the_ID();
                $post_title = get_the_title();
                
                $results['processed']++;
                
                $generation_result = $generator->generate($post_id);
                
                if (is_wp_error($generation_result)) {
                    if ($generation_result->get_error_code() === 'excluded') {
                        $results['skipped']++;
                        $results['details'][] = array(
                            'id' => $post_id,
                            'title' => $post_title,
                            'status' => 'skipped',
                            'message' => $generation_result->get_error_message(),
                        );
                    } else {
                        $results['errors']++;
                        $results['details'][] = array(
                            'id' => $post_id,
                            'title' => $post_title,
                            'status' => 'error',
                            'message' => $generation_result->get_error_message(),
                        );
                    }
                } else {
                    $results['converted']++;
                    $results['details'][] = array(
                        'id' => $post_id,
                        'title' => $post_title,
                        'status' => 'converted',
                        'message' => __('Successfully converted', 'wp-to-html'),
                    );
                }
            }
            
            wp_reset_postdata();
        }
        
        // Check if there are more posts
        $total = $this->get_eligible_posts_count();
        $results['has_more'] = ($offset + self::BATCH_SIZE) < $total;
        $results['total'] = $total;
        
        return $results;
    }
    
    /**
     * Get eligible post types
     */
    private function get_eligible_post_types() {
        $post_types = get_post_types(array('public' => true), 'names');
        $excluded = array('attachment', 'product', 'product_variation');
        
        return array_values(array_diff($post_types, $excluded));
    }
    
    /**
     * Bulk convert all eligible posts (CLI method)
     */
    public function convert_all() {
        $post_types = $this->get_eligible_post_types();
        
        $args = array(
            'post_type' => $post_types,
            'post_status' => 'publish',
            'posts_per_page' => -1,
        );
        
        $query = new WP_Query($args);
        $generator = WP_To_HTML_Generator::get_instance();
        
        $results = array(
            'total' => $query->post_count,
            'converted' => 0,
            'skipped' => 0,
            'errors' => 0,
        );
        
        if ($query->have_posts()) {
            while ($query->have_posts()) {
                $query->the_post();
                $post_id = get_the_ID();
                
                $generation_result = $generator->generate($post_id);
                
                if (is_wp_error($generation_result)) {
                    if ($generation_result->get_error_code() === 'excluded') {
                        $results['skipped']++;
                    } else {
                        $results['errors']++;
                    }
                } else {
                    $results['converted']++;
                }
            }
            
            wp_reset_postdata();
        }
        
        return $results;
    }
}