<?php
/**
 * Tracks and reports per-user lesson progress.
 *
 * @package Aims_Infosoft_LMS
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Reads/writes rows in the custom lesson progress table.
 */
class AIMSLMS_Progress_Tracker {

	/**
	 * Get the progress table name.
	 *
	 * @return string Fully-prefixed table name.
	 */
	private static function table() {
		global $wpdb;
		return $wpdb->prefix . 'aimslms_course_progress';
	}

	/**
	 * Upsert a lesson's video-timestamp/completion-percentage progress for the current user.
	 *
	 * @param array $data Progress data: lesson_id, course_id, time, percentage.
	 */
	public static function save( $data ) {
		global $wpdb;

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table, no WP API alternative.
		$wpdb->replace(
			self::table(),
			array(
				'user_id'               => get_current_user_id(),
				'lesson_id'             => $data['lesson_id'],
				'course_id'             => $data['course_id'],
				'video_timestamp'       => $data['time'],
				'completion_percentage' => $data['percentage'],
				'completed'             => $data['percentage'] >= 100 ? 1 : 0,
				'last_accessed'         => current_time( 'mysql' ),
			),
			array( '%d', '%d', '%d', '%d', '%d', '%d', '%s' )
		);
	}

	/**
	 * Mark a lesson complete for the current user, updating the existing progress row if one exists.
	 *
	 * @param array $data Progress data: lesson_id, course_id, completed.
	 */
	public static function mark_complete( $data ) {
		global $wpdb;

		$table = self::table();

		$where = array(
			'user_id'   => get_current_user_id(),
			'lesson_id' => (int) $data['lesson_id'],
		);

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table, no WP API alternative.
		$exists = $wpdb->get_var(
			$wpdb->prepare(
				// phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- $table is derived from $wpdb->prefix, not user input.
				"SELECT id FROM {$table} WHERE user_id = %d AND lesson_id = %d",
				$where['user_id'],
				$where['lesson_id']
			)
		);

		$payload = array(
			'course_id'             => (int) $data['course_id'],
			'completed'             => (int) $data['completed'],
			'completion_percentage' => (int) 100,
			'last_accessed'         => current_time( 'mysql' ),
		);

		$formats = array( '%d', '%d', '%d', '%s' );
		if ( $exists ) {

			// ✅ UPDATE.
			// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table, no WP API alternative.
			$wpdb->update(
				$table,
				$payload,
				$where,
				$formats,
				array( '%d', '%d', '%d' )
			);

		} else {

			// ✅ INSERT.
			// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery -- Custom table, no WP API alternative.
			$wpdb->insert(
				$table,
				array_merge( $where, $payload ),
				array( '%d', '%d', '%d', '%d', '%d', '%s' )
			);
		}
	}

	/**
	 * Get the current user's saved progress row for a lesson.
	 *
	 * @param int $lesson_id Lesson ID.
	 * @return object|null Progress row, or null if none saved yet.
	 */
	public static function get_progress( $lesson_id ) {
		global $wpdb;

		// phpcs:disable WordPress.DB.PreparedSQL.NotPrepared -- self::table() returns $wpdb->prefix . 'aimslms_course_progress', not user input.
		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table, no WP API alternative.
		return $wpdb->get_row(
			$wpdb->prepare(
				'SELECT * FROM ' . self::table() . '
                 WHERE user_id=%d AND lesson_id=%d',
				get_current_user_id(),
				$lesson_id
			)
		);
		// phpcs:enable WordPress.DB.PreparedSQL.NotPrepared
	}
}