<?php
/**
 * Installer Class
 *
 * @package AI_Commerce_Assistant
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

class AICA_Installer {

	/**
	 * Activate plugin
	 */
	public static function activate() {

		self::create_tables();
		self::set_default_options();
		self::schedule_events();

		update_option( 'aica_installed', 1, false );
		update_option( 'aica_version', AICA_VERSION );
		update_option( 'aica_activated', time(), false );

		set_transient( 'aica_activation_redirect', true, 30 );

		flush_rewrite_rules();
	}

	/**
	 * Create DB tables
	 *
	 * NO direct queries
	 * NO SHOW TABLES
	 * NO ALTER TABLE
	 * Only dbDelta (WordPress standard)
	 */
	private static function create_tables() {
		global $wpdb;

		require_once ABSPATH . 'wp-admin/includes/upgrade.php';

		$charset_collate = $wpdb->get_charset_collate();

		$table_products      = $wpdb->prefix . 'aica_indexed_products';
		$table_conversations = $wpdb->prefix . 'aica_conversations';
		$table_analytics     = $wpdb->prefix . 'aica_analytics';

		$sql_products = "CREATE TABLE {$table_products} (
			id bigint(20) NOT NULL AUTO_INCREMENT,
			product_id bigint(20) NOT NULL,
			content longtext NOT NULL,
			metadata longtext DEFAULT NULL,
			price decimal(10,2) DEFAULT NULL,
			stock_quantity int(11) DEFAULT NULL,
			categories varchar(255) DEFAULT NULL,
			embedding longtext DEFAULT NULL,
			last_updated datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
			PRIMARY KEY  (id),
			KEY product_id (product_id),
			KEY price (price),
			FULLTEXT KEY content (content)
		) {$charset_collate};";

		$sql_conversations = "CREATE TABLE {$table_conversations} (
			id bigint(20) NOT NULL AUTO_INCREMENT,
			session_id varchar(100) NOT NULL,
			user_id bigint(20) DEFAULT NULL,
			message longtext NOT NULL,
			role varchar(20) NOT NULL,
			metadata longtext DEFAULT NULL,
			created_at datetime DEFAULT CURRENT_TIMESTAMP,
			PRIMARY KEY  (id),
			KEY session_id (session_id),
			KEY user_id (user_id),
			KEY created_at (created_at)
		) {$charset_collate};";

		$sql_analytics = "CREATE TABLE {$table_analytics} (
			id bigint(20) NOT NULL AUTO_INCREMENT,
			session_id varchar(100) NOT NULL,
			event_type varchar(50) NOT NULL,
			event_data longtext DEFAULT NULL,
			created_at datetime DEFAULT CURRENT_TIMESTAMP,
			PRIMARY KEY  (id),
			KEY session_id (session_id),
			KEY event_type (event_type),
			KEY created_at (created_at)
		) {$charset_collate};";

		ob_start();
		dbDelta( $sql_products );
		dbDelta( $sql_conversations );
		dbDelta( $sql_analytics );
		ob_end_clean();
	}

	/**
	 * Default options
	 */
	private static function set_default_options() {

		if ( false === get_option( 'aica_settings', false ) ) {

			add_option(
				'aica_settings',
				array(
					'enable_widget'             => 'yes',
					'widget_position'           => 'bottom-right',

					'ai_provider'               => 'openai',
					'api_key'                   => '',
					'model'                     => 'gpt-4o-mini',
					'max_tokens'                => 500,
					'temperature'               => 0.7,

					'primary_color'             => '#0066FF',
					'widget_title'              => __( 'AI Assistant', 'aica-smart-ai-commerce-assistant' ),
					'greeting_message'          => __( 'Hi! How can I help you today?', 'aica-smart-ai-commerce-assistant' ),

					'enable_product_recommendations' => 'yes',
					'enable_cart_actions'            => 'yes',

					'store_conversations'       => 'yes',
					'data_retention_days'       => 30,
				),
				'',
				false
			);
		}
	}

	/**
	 * Cron events
	 */
	private static function schedule_events() {

		if ( ! wp_next_scheduled( 'aica_reindex_products' ) ) {
			wp_schedule_event( time(), 'daily', 'aica_reindex_products' );
		}

		if ( ! wp_next_scheduled( 'aica_cleanup_old_data' ) ) {
			wp_schedule_event( time(), 'weekly', 'aica_cleanup_old_data' );
		}
	}

	/**
	 * Check install state
	 *
	 * ZERO DB queries
	 */
	public static function tables_exist() {
		return (bool) get_option( 'aica_installed', false );
	}
}