<?php
/**
 * Analytics service.
 *
 * @package ModernAudioPlayer
 */

namespace ModernAudioPlayer;

defined( 'ABSPATH' ) || exit;

class Analytics {
	/**
	 * Create database table on activation.
	 *
	 * @return void
	 */
	public static function create_table() {
		global $wpdb;

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

		require_once ABSPATH . 'wp-admin/includes/upgrade.php';

		$sql = "CREATE TABLE {$table_name} (
			id bigint(20) unsigned NOT NULL AUTO_INCREMENT,
			source_hash varchar(64) NOT NULL,
			audio_src text NOT NULL,
			track_title varchar(255) NOT NULL DEFAULT '',
			play_count bigint(20) unsigned NOT NULL DEFAULT 0,
			last_played datetime NULL DEFAULT NULL,
			created_at datetime NOT NULL,
			updated_at datetime NOT NULL,
			PRIMARY KEY  (id),
			UNIQUE KEY source_hash (source_hash),
			KEY play_count (play_count),
			KEY last_played (last_played)
		) {$charset_collate};";

		dbDelta( $sql );
	}

	/**
	 * Get the analytics table name.
	 *
	 * @return string
	 */
	public static function table_name() {
		global $wpdb;
		return $wpdb->prefix . 'map_analytics';
	}

	/**
	 * Build a stable source hash.
	 *
	 * @param string $audio_src Audio URL.
	 * @return string
	 */
	public static function build_source_hash( $audio_src ) {
		return hash( 'sha256', esc_url_raw( trim( (string) $audio_src ) ) );
	}

	/**
	 * Record a play.
	 *
	 * Count rule:
	 * One request counts once for the rendered player instance session. The frontend
	 * only sends this call on the first meaningful play event per player rendered on a page.
	 *
	 * @param string $audio_src Audio source URL.
	 * @param string $track_title Track title.
	 * @return bool
	 */
	public static function record_play( $audio_src, $track_title = '' ) {
		global $wpdb;

		$audio_src    = esc_url_raw( $audio_src );
		$track_title  = sanitize_text_field( $track_title );
		$source_hash  = self::build_source_hash( $audio_src );
		$table_name   = self::table_name();
		$current_time = current_time( 'mysql', true );

		if ( empty( $audio_src ) ) {
			return false;
		}

		$existing_id = $wpdb->get_var(
			$wpdb->prepare(
				"SELECT id FROM {$table_name} WHERE source_hash = %s LIMIT 1",
				$source_hash
			)
		);

		if ( $existing_id ) {
			$result = $wpdb->query(
				$wpdb->prepare(
					"UPDATE {$table_name}
					SET play_count = play_count + 1,
						track_title = %s,
						last_played = %s,
						updated_at = %s
					WHERE source_hash = %s",
					$track_title,
					$current_time,
					$current_time,
					$source_hash
				)
			);

			return false !== $result;
		}

		$result = $wpdb->insert(
			$table_name,
			array(
				'source_hash' => $source_hash,
				'audio_src'   => $audio_src,
				'track_title' => $track_title,
				'play_count'  => 1,
				'last_played' => $current_time,
				'created_at'  => $current_time,
				'updated_at'  => $current_time,
			),
			array( '%s', '%s', '%s', '%d', '%s', '%s', '%s' )
		);

		return false !== $result;
	}

	/**
	 * Fetch top tracks.
	 *
	 * @param int $limit Row limit.
	 * @return array<int, object>
	 */
	public static function get_top_tracks( $limit = 20 ) {
		global $wpdb;

		$table_name = self::table_name();
		$limit      = max( 1, absint( $limit ) );

		return $wpdb->get_results(
			$wpdb->prepare(
				"SELECT source_hash, audio_src, track_title, play_count, last_played
				FROM {$table_name}
				ORDER BY play_count DESC, last_played DESC
				LIMIT %d",
				$limit
			)
		);
	}

	/**
	 * Get aggregate stats.
	 *
	 * @return array<string, int|string|null>
	 */
	public static function get_summary() {
		global $wpdb;

		$table_name = self::table_name();
		$row        = $wpdb->get_row(
			"SELECT COUNT(*) AS track_count, COALESCE(SUM(play_count), 0) AS total_plays, MAX(last_played) AS last_played FROM {$table_name}",
			ARRAY_A
		);

		return array(
			'track_count' => isset( $row['track_count'] ) ? (int) $row['track_count'] : 0,
			'total_plays' => isset( $row['total_plays'] ) ? (int) $row['total_plays'] : 0,
			'last_played' => $row['last_played'] ?? null,
		);
	}
}