<?php
/**
 * Plugin Loader Class
 *
 * Manages plugin initialization and coordinates all components
 *
 * @package AI_Thumbnails_Maker
 * @since 1.0.0
 */

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

/**
 * Main plugin loader class
 */
class AITM_Plugin_Loader {

	/**
	 * Plugin settings
	 *
	 * @var array
	 */
	private $settings;

	/**
	 * Thumbnail generator instance
	 *
	 * @var AITM_Thumbnail_Generator
	 */
	private $thumbnail_generator;

	/**
	 * Constructor
	 */
	public function __construct() {
		$this->settings = get_option( 'aitm_settings', array() );
	}

	/**
	 * Run the plugin
	 */
	public function run() {
		// Initialize thumbnail generator
		$this->init_thumbnail_generator();

		// Initialize admin components
		if ( is_admin() ) {
			$this->init_admin();
		}

		// Register AJAX handlers
		$this->init_ajax_handlers();

		// Register hooks for auto generation
		$this->init_auto_generation_hooks();
	}

	/**
	 * Initialize thumbnail generator
	 */
	private function init_thumbnail_generator() {
		$this->thumbnail_generator = new AITM_Thumbnail_Generator( $this->settings );
	}

	/**
	 * Initialize admin components
	 */
	private function init_admin() {
		// First create main menu (Dashboard)
		$dashboard_page = new AITM_Dashboard_Page();
		add_action( 'admin_menu', array( $dashboard_page, 'add_menu_page' ), 9 );
		add_action( 'admin_enqueue_scripts', array( $dashboard_page, 'enqueue_scripts' ) );

		// Add Settings page (priority 10 to be second in submenu)
		$admin_settings = new AITM_Admin_Settings();
		add_action( 'admin_menu', array( $admin_settings, 'add_menu_page' ), 10 );
		add_action( 'admin_init', array( $admin_settings, 'register_settings' ) );
		add_action( 'admin_enqueue_scripts', array( $admin_settings, 'enqueue_scripts' ) );

		// Add Regenerate page (priority 11 to be third in submenu)
		require_once AITM_PLUGIN_DIR . 'admin/class-regenerate-page.php';
		$regenerate_page = new AITM_Regenerate_Page();
		add_action( 'admin_menu', array( $regenerate_page, 'add_menu_page' ), 11 );
		add_action( 'admin_enqueue_scripts', array( $regenerate_page, 'enqueue_scripts' ) );

		// Add What's New page (priority 12 to be fourth in submenu)
		require_once AITM_PLUGIN_DIR . 'admin/class-whats-new-page.php';
		$whats_new_page = new AITM_Whats_New_Page();
		add_action( 'admin_menu', array( $whats_new_page, 'add_menu_page' ), 12 );
		add_action( 'admin_enqueue_scripts', array( $whats_new_page, 'enqueue_scripts' ) );

		// Initialize admin columns (thumbnail preview in posts list)
		new AITM_Admin_Columns();
	}

	/**
	 * Initialize AJAX handlers
	 */
	private function init_ajax_handlers() {
		// Get posts list for generation
		add_action( 'wp_ajax_aitm_get_posts', array( $this, 'ajax_get_posts' ) );

		// Generate thumbnail for post
		add_action( 'wp_ajax_aitm_generate_thumbnail', array( $this, 'ajax_generate_thumbnail' ) );

		// Delete thumbnail
		add_action( 'wp_ajax_aitm_delete_thumbnail', array( $this, 'ajax_delete_thumbnail' ) );

		// Get statistics
		add_action( 'wp_ajax_aitm_get_statistics', array( $this, 'ajax_get_statistics' ) );

		// Regenerate thumbnails handlers
		add_action( 'wp_ajax_aitm_get_attachments', array( $this, 'ajax_get_attachments' ) );
		add_action( 'wp_ajax_aitm_regenerate_attachment', array( $this, 'ajax_regenerate_attachment' ) );
		add_action( 'wp_ajax_aitm_get_thumbnail_sizes', array( $this, 'ajax_get_thumbnail_sizes' ) );
	}

	/**
	 * Initialize auto generation hooks
	 */
	private function init_auto_generation_hooks() {
		$auto_generation = $this->settings['auto_generation'] ?? true;

		if ( ! $auto_generation ) {
			return;
		}

		$enabled_post_types = $this->settings['enabled_post_types'] ?? array( 'post', 'page' );

		// Hook on post save
		add_action( 'save_post', array( $this, 'auto_generate_on_save' ), 10, 3 );

		// Hook on post status transition
		add_action( 'transition_post_status', array( $this, 'auto_generate_on_transition' ), 10, 3 );
	}

	/**
	 * Auto generate thumbnail on post save
	 *
	 * @param int     $post_id Post ID.
	 * @param WP_Post $post Post object.
	 * @param bool    $update Whether this is an existing post being updated.
	 */
	public function auto_generate_on_save( $post_id, $post, $update ) {
		// Skip autosaves and revisions
		if ( wp_is_post_autosave( $post_id ) || wp_is_post_revision( $post_id ) ) {
			return;
		}

		// Check post type
		$enabled_post_types = $this->settings['enabled_post_types'] ?? array( 'post', 'page' );
		if ( ! in_array( $post->post_type, $enabled_post_types, true ) ) {
			return;
		}

		// Check post status
		if ( $post->post_status !== 'publish' ) {
			return;
		}

		// Check if already has thumbnail
		$overwrite_existing = $this->settings['overwrite_existing'] ?? false;
		if ( ! $overwrite_existing && has_post_thumbnail( $post_id ) ) {
			return;
		}

		// Generate thumbnail
		$this->thumbnail_generator->generate_for_post( $post_id );
	}

	/**
	 * Auto generate thumbnail on post status transition
	 *
	 * @param string  $new_status New post status.
	 * @param string  $old_status Old post status.
	 * @param WP_Post $post Post object.
	 */
	public function auto_generate_on_transition( $new_status, $old_status, $post ) {
		// Generate only when transitioning to publish
		if ( $new_status !== 'publish' || $old_status === 'publish' ) {
			return;
		}

		// Check post type
		$enabled_post_types = $this->settings['enabled_post_types'] ?? array( 'post', 'page' );
		if ( ! in_array( $post->post_type, $enabled_post_types, true ) ) {
			return;
		}

		// Check if already has thumbnail
		$overwrite_existing = $this->settings['overwrite_existing'] ?? false;
		if ( ! $overwrite_existing && has_post_thumbnail( $post->ID ) ) {
			return;
		}

		// Generate thumbnail
		$this->thumbnail_generator->generate_for_post( $post->ID );
	}

	/**
	 * AJAX: Get posts for generation
	 */
	public function ajax_get_posts() {
		check_ajax_referer( 'aitm_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied', 'ai-thumbnails-maker' ) ) );
		}

		$post_type   = isset( $_POST['post_type'] ) ? sanitize_text_field( wp_unslash( $_POST['post_type'] ) ) : 'post';
		$with_thumb  = isset( $_POST['with_thumb'] ) ? (bool) $_POST['with_thumb'] : false;

		$args = array(
			'post_type'      => $post_type,
			'post_status'    => 'publish',
			'posts_per_page' => -1,
			'fields'         => 'ids',
		);

		// Reload settings to get fresh overwrite_existing value
		$fresh_settings = get_option( 'aitm_settings', array() );
		$overwrite_existing = $fresh_settings['overwrite_existing'] ?? false;

		// If overwrite is disabled or with_thumb is false, filter posts without thumbnail
		if ( ! $overwrite_existing || ! $with_thumb ) {
			$args['meta_query'] = array(
				array(
					'key'     => '_thumbnail_id',
					'compare' => 'NOT EXISTS',
				),
			);
		}

		$query = new WP_Query( $args );
		wp_send_json_success( array( 'posts' => $query->posts ) );
	}

	/**
	 * AJAX: Generate thumbnail for post
	 */
	public function ajax_generate_thumbnail() {
		check_ajax_referer( 'aitm_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied', 'ai-thumbnails-maker' ) ) );
		}

		$post_id = isset( $_POST['post_id'] ) ? absint( $_POST['post_id'] ) : 0;

		if ( ! $post_id ) {
			wp_send_json_error( array( 'message' => __( 'Invalid post ID', 'ai-thumbnails-maker' ) ) );
		}

		// Reload settings to get fresh values
		$fresh_settings          = get_option( 'aitm_settings', array() );
		$this->thumbnail_generator = new AITM_Thumbnail_Generator( $fresh_settings );

		$result = $this->thumbnail_generator->generate_for_post( $post_id );

		if ( $result['success'] ) {
			wp_send_json_success( $result );
		} else {
			wp_send_json_error( $result );
		}
	}

	/**
	 * AJAX: Delete thumbnail
	 */
	public function ajax_delete_thumbnail() {
		check_ajax_referer( 'aitm_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied', 'ai-thumbnails-maker' ) ) );
		}

		$post_id = isset( $_POST['post_id'] ) ? absint( $_POST['post_id'] ) : 0;

		if ( ! $post_id ) {
			wp_send_json_error( array( 'message' => __( 'Invalid post ID', 'ai-thumbnails-maker' ) ) );
		}

		$deleted = delete_post_thumbnail( $post_id );

		if ( $deleted ) {
			wp_send_json_success( array( 'message' => __( 'Thumbnail deleted', 'ai-thumbnails-maker' ) ) );
		} else {
			wp_send_json_error( array( 'message' => __( 'Failed to delete thumbnail', 'ai-thumbnails-maker' ) ) );
		}
	}

	/**
	 * AJAX: Get statistics
	 */
	public function ajax_get_statistics() {
		check_ajax_referer( 'aitm_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied', 'ai-thumbnails-maker' ) ) );
		}

		$post_type = isset( $_POST['post_type'] ) ? sanitize_text_field( wp_unslash( $_POST['post_type'] ) ) : 'post';

		// Reload settings to get fresh values
		$fresh_settings          = get_option( 'aitm_settings', array() );
		$this->thumbnail_generator = new AITM_Thumbnail_Generator( $fresh_settings );

		$stats = $this->thumbnail_generator->get_statistics( $post_type );
		wp_send_json_success( $stats );
	}

	/**
	 * AJAX: Get attachments for regeneration
	 */
	public function ajax_get_attachments() {
		check_ajax_referer( 'aitm_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied', 'ai-thumbnails-maker' ) ) );
		}

		$filter = isset( $_POST['filter'] ) ? sanitize_text_field( wp_unslash( $_POST['filter'] ) ) : 'all';

		$args = array(
			'post_type'      => 'attachment',
			'post_mime_type' => 'image',
			'post_status'    => 'inherit',
			'posts_per_page' => -1,
			'fields'         => 'ids',
		);

		// Filter for featured images only
	if ( $filter === 'featured' ) {
		global $wpdb;
		
		// Try to get from cache
		$cache_key    = 'aitm_featured_ids_' . $post_type;
		$featured_ids = wp_cache_get( $cache_key, 'aitm' );
		
		if ( false === $featured_ids ) {
			// Get all attachment IDs that are used as featured images
			$featured_ids = $wpdb->get_col(
				"SELECT DISTINCT meta_value 
				FROM {$wpdb->postmeta} 
				WHERE meta_key = '_thumbnail_id' 
				AND meta_value > 0"
			);
			
			// Cache for 5 minutes
			wp_cache_set( $cache_key, $featured_ids, 'aitm', 300 );
		}

			if ( empty( $featured_ids ) ) {
				wp_send_json_success( array( 'attachments' => array() ) );
				return;
			}

			$args['post__in'] = $featured_ids;
		}

		$query = new WP_Query( $args );
		wp_send_json_success( array( 'attachments' => $query->posts ) );
	}

	/**
	 * AJAX: Regenerate attachment
	 */
	public function ajax_regenerate_attachment() {
		check_ajax_referer( 'aitm_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied', 'ai-thumbnails-maker' ) ) );
		}

		$attachment_id = isset( $_POST['attachment_id'] ) ? absint( $_POST['attachment_id'] ) : 0;

		if ( ! $attachment_id ) {
			wp_send_json_error( array( 'message' => __( 'Invalid attachment ID', 'ai-thumbnails-maker' ) ) );
		}

		$options = array(
			'only_missing' => isset( $_POST['only_missing'] ) ? (bool) $_POST['only_missing'] : true,
			'delete_old'   => isset( $_POST['delete_old'] ) ? (bool) $_POST['delete_old'] : false,
		);

		require_once AITM_PLUGIN_DIR . 'includes/class-thumbnail-regenerator.php';
		$regenerator = new AITM_Thumbnail_Regenerator();
		$result      = $regenerator->regenerate_attachment( $attachment_id, $options );

		if ( $result['success'] ) {
			wp_send_json_success( $result );
		} else {
			wp_send_json_error( $result );
		}
	}

	/**
	 * AJAX: Get thumbnail sizes
	 */
	public function ajax_get_thumbnail_sizes() {
		check_ajax_referer( 'aitm_nonce', 'nonce' );

		if ( ! current_user_can( 'manage_options' ) ) {
			wp_send_json_error( array( 'message' => __( 'Permission denied', 'ai-thumbnails-maker' ) ) );
		}

		require_once AITM_PLUGIN_DIR . 'includes/class-thumbnail-regenerator.php';
		$regenerator = new AITM_Thumbnail_Regenerator();
		$sizes       = $regenerator->get_registered_sizes();

		wp_send_json_success( array( 'sizes' => $sizes ) );
	}
}