<?php
/**
 * MCP request/response logger with auto-cleanup.
 *
 * @package Wlconduit
 */

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

/**
 * Handles logging of MCP requests and responses to a custom database table.
 *
 * @since 1.0.0
 */
class Wlconduit_MCP_Logger {

	const TABLE_NAME     = 'wlconduit_mcp_logs';
	const CRON_HOOK      = 'wlconduit_mcp_logs_cleanup';
	const DB_VERSION_KEY = 'wlconduit_mcp_logs_db_version';
	const DB_VERSION     = '1.0';

	/**
	 * Create the logs database table.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public static function create_table(): void {
		global $wpdb;

		$table_name      = $wpdb->prefix . self::TABLE_NAME;
		$charset_collate = $wpdb->get_charset_collate();

		// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Table name and charset are safe internal values.
		$sql = "CREATE TABLE {$table_name} (
			id BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
			created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
			user_id BIGINT UNSIGNED NOT NULL DEFAULT 0,
			method VARCHAR(100) NOT NULL DEFAULT '',
			tool_name VARCHAR(100) NOT NULL DEFAULT '',
			request LONGTEXT NOT NULL,
			response LONGTEXT NOT NULL,
			status VARCHAR(20) NOT NULL DEFAULT 'success',
			PRIMARY KEY (id),
			KEY created_at (created_at),
			KEY method (method),
			KEY user_id (user_id)
		) {$charset_collate};";

		require_once ABSPATH . 'wp-admin/includes/upgrade.php';
		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.SchemaChange -- Custom logging table created on plugin activation via dbDelta().
		dbDelta( $sql );

		update_option( self::DB_VERSION_KEY, self::DB_VERSION );
	}

	/**
	 * Schedule the daily cleanup cron event.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public static function schedule_cleanup(): void {
		if ( ! wp_next_scheduled( self::CRON_HOOK ) ) {
			wp_schedule_event( time(), 'daily', self::CRON_HOOK );
		}
	}

	/**
	 * Unschedule the cleanup cron event.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public static function unschedule_cleanup(): void {
		$timestamp = wp_next_scheduled( self::CRON_HOOK );
		if ( $timestamp ) {
			wp_unschedule_event( $timestamp, self::CRON_HOOK );
		}
	}

	/**
	 * Check if logging is enabled.
	 *
	 * @since 1.0.0
	 *
	 * @return bool
	 */
	public function is_enabled(): bool {
		$enabled = get_option( 'wlconduit_logging_enabled', '1' ) === '1';

		/**
		 * Filter to override the logging setting programmatically.
		 *
		 * Takes priority over the admin setting.
		 *
		 * @since 1.0.0
		 *
		 * @param bool $enabled Whether logging is enabled.
		 */
		return (bool) apply_filters( 'wlconduit_mcp_logging_enabled', $enabled );
	}

	/**
	 * Log an MCP request and response.
	 *
	 * @since 1.0.0
	 *
	 * @param string $method    The JSON-RPC method name.
	 * @param string $tool_name The tool name if applicable.
	 * @param array  $request   The full request payload.
	 * @param array  $response  The full response payload.
	 * @param string $status    Either 'success' or 'error'.
	 * @return void
	 */
	public function log( string $method, string $tool_name, array $request, array $response, string $status ): void {
		if ( ! $this->is_enabled() ) {
			return;
		}

		global $wpdb;

		$table_name = $wpdb->prefix . self::TABLE_NAME;

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery -- Custom table, no WP API available.
		$wpdb->insert(
			$table_name,
			array(
				'user_id'   => get_current_user_id(),
				'method'    => sanitize_text_field( $method ),
				'tool_name' => sanitize_text_field( $tool_name ),
				'request'   => wp_json_encode( $request ),
				'response'  => wp_json_encode( $response ),
				'status'    => sanitize_text_field( $status ),
			),
			array( '%d', '%s', '%s', '%s', '%s', '%s' )
		);
	}

	/**
	 * Delete logs older than the configured retention period.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public function cleanup(): void {
		global $wpdb;

		$retention_days = absint( get_option( 'wlconduit_log_retention_days', 30 ) );

		if ( 0 === $retention_days ) {
			return;
		}

		$table_name = $wpdb->prefix . self::TABLE_NAME;

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table, no WP API available.
		$wpdb->query(
			$wpdb->prepare(
				'DELETE FROM %i WHERE created_at < DATE_SUB(NOW(), INTERVAL %d DAY)',
				$table_name,
				$retention_days
			)
		);
	}

	/**
	 * Drop the logs table. Used on uninstall.
	 *
	 * @since 1.0.0
	 *
	 * @return void
	 */
	public static function drop_table(): void {
		global $wpdb;

		$table_name = $wpdb->prefix . self::TABLE_NAME;

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching, WordPress.DB.DirectDatabaseQuery.SchemaChange -- Custom logs table dropped on plugin uninstall; no WP API exists for dropping a plugin-owned table.
		$wpdb->query( $wpdb->prepare( 'DROP TABLE IF EXISTS %i', $table_name ) );

		delete_option( self::DB_VERSION_KEY );
	}
}