<?php
/**
 * Digital Delivery Handler for WooCommerce.
 *
 * @package WP_FediStream
 */

namespace WP_FediStream\WooCommerce;

// Prevent direct file access.
if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Handles digital delivery of purchased music.
 */
class DigitalDelivery {

	/**
	 * Constructor.
	 */
	public function __construct() {
		// Handle download requests.
		add_action( 'init', array( $this, 'handle_download_request' ) );

		// Add download links to order emails.
		add_action( 'woocommerce_email_after_order_table', array( $this, 'add_download_links_to_email' ), 10, 4 );

		// Add download section to My Account.
		add_action( 'woocommerce_account_downloads_endpoint', array( $this, 'customize_downloads_display' ) );

		// Generate secure download tokens.
		add_filter( 'woocommerce_download_file_force', array( $this, 'force_download_for_audio' ), 10, 2 );
	}

	/**
	 * Handle download requests.
	 *
	 * @return void
	 */
	public function handle_download_request(): void {
		// phpcs:ignore WordPress.Security.NonceVerification.Recommended
		if ( ! isset( $_GET['fedistream_download'] ) ) {
			return;
		}

		$type = sanitize_text_field( wp_unslash( $_GET['fedistream_download'] ) ); // phpcs:ignore WordPress.Security.NonceVerification.Recommended

		// Verify user is logged in.
		if ( ! is_user_logged_in() ) {
			wp_die( esc_html__( 'You must be logged in to download files.', 'wp-fedistream' ) );
		}

		$user_id = get_current_user_id();

		if ( 'track' === $type ) {
			$this->handle_track_download( $user_id );
		} elseif ( 'album' === $type ) {
			$this->handle_album_download( $user_id );
		}
	}

	/**
	 * Handle track download.
	 *
	 * @param int $user_id User ID.
	 * @return void
	 */
	private function handle_track_download( int $user_id ): void {
		$track_id = isset( $_GET['track_id'] ) ? absint( $_GET['track_id'] ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Recommended
		$format   = isset( $_GET['format'] ) ? sanitize_text_field( wp_unslash( $_GET['format'] ) ) : 'mp3'; // phpcs:ignore WordPress.Security.NonceVerification.Recommended

		if ( ! $track_id ) {
			wp_die( esc_html__( 'Invalid track.', 'wp-fedistream' ) );
		}

		// Verify purchase.
		if ( ! Integration::user_has_purchased( $user_id, 'track', $track_id ) ) {
			wp_die( esc_html__( 'You have not purchased this track.', 'wp-fedistream' ) );
		}

		$track = get_post( $track_id );
		if ( ! $track || 'fedistream_track' !== $track->post_type ) {
			wp_die( esc_html__( 'Track not found.', 'wp-fedistream' ) );
		}

		// Get audio file.
		$audio_id = get_post_meta( $track_id, '_fedistream_audio_file', true );
		if ( ! $audio_id ) {
			wp_die( esc_html__( 'No audio file available.', 'wp-fedistream' ) );
		}

		$file_path = get_attached_file( $audio_id );
		if ( ! $file_path || ! file_exists( $file_path ) ) {
			wp_die( esc_html__( 'File not found.', 'wp-fedistream' ) );
		}

		// Convert format if needed.
		$converted_file = $this->get_converted_file( $file_path, $format, $track_id );

		// Generate filename.
		$filename = sanitize_file_name( $track->post_title ) . '.' . $format;

		// Serve the file.
		$this->serve_file( $converted_file, $filename, $format );
	}

	/**
	 * Handle album download (ZIP of all tracks).
	 *
	 * @param int $user_id User ID.
	 * @return void
	 */
	private function handle_album_download( int $user_id ): void {
		$album_id = isset( $_GET['album_id'] ) ? absint( $_GET['album_id'] ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Recommended
		$format   = isset( $_GET['format'] ) ? sanitize_text_field( wp_unslash( $_GET['format'] ) ) : 'mp3'; // phpcs:ignore WordPress.Security.NonceVerification.Recommended

		if ( ! $album_id ) {
			wp_die( esc_html__( 'Invalid album.', 'wp-fedistream' ) );
		}

		// Verify purchase.
		if ( ! Integration::user_has_purchased( $user_id, 'album', $album_id ) ) {
			wp_die( esc_html__( 'You have not purchased this album.', 'wp-fedistream' ) );
		}

		$album = get_post( $album_id );
		if ( ! $album || 'fedistream_album' !== $album->post_type ) {
			wp_die( esc_html__( 'Album not found.', 'wp-fedistream' ) );
		}

		// Get tracks.
		$tracks = get_posts(
			array(
				'post_type'      => 'fedistream_track',
				'post_status'    => 'publish',
				'posts_per_page' => -1,
				'meta_key'       => '_fedistream_track_number', // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_key
				'orderby'        => 'meta_value_num',
				'order'          => 'ASC',
				'meta_query'     => array( // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_query
					array(
						'key'   => '_fedistream_album_id',
						'value' => $album_id,
					),
				),
			)
		);

		if ( empty( $tracks ) ) {
			wp_die( esc_html__( 'No tracks found in this album.', 'wp-fedistream' ) );
		}

		// Create ZIP file.
		$zip_file = $this->create_album_zip( $album, $tracks, $format );

		if ( ! $zip_file ) {
			wp_die( esc_html__( 'Failed to create download package.', 'wp-fedistream' ) );
		}

		// Generate filename.
		$artist_id   = get_post_meta( $album_id, '_fedistream_album_artist', true );
		$artist      = $artist_id ? get_post( $artist_id ) : null;
		$artist_name = $artist ? $artist->post_title : 'Unknown Artist';

		$filename = sanitize_file_name( $artist_name . ' - ' . $album->post_title ) . '.' . strtoupper( $format ) . '.zip';

		// Serve the file.
		$this->serve_file( $zip_file, $filename, 'zip' );

		// Clean up temp file.
		wp_delete_file( $zip_file );
	}

	/**
	 * Get converted file path.
	 *
	 * @param string $source_path Source file path.
	 * @param string $format      Target format.
	 * @param int    $track_id    Track ID for caching.
	 * @return string Converted file path.
	 */
	private function get_converted_file( string $source_path, string $format, int $track_id ): string {
		$source_ext = strtolower( pathinfo( $source_path, PATHINFO_EXTENSION ) );

		// If same format, return source.
		if ( $source_ext === $format ) {
			return $source_path;
		}

		// Check for cached conversion.
		$cache_dir  = wp_upload_dir()['basedir'] . '/fedistream-cache/';
		$cache_file = $cache_dir . 'track-' . $track_id . '.' . $format;

		if ( file_exists( $cache_file ) ) {
			return $cache_file;
		}

		// Create cache directory.
		if ( ! file_exists( $cache_dir ) ) {
			wp_mkdir_p( $cache_dir );
		}

		// For now, return source file (format conversion would require FFmpeg).
		// In production, you'd use FFmpeg or similar for conversion.
		// This is a placeholder for the conversion logic.
		return $source_path;
	}

	/**
	 * Create ZIP file for album download.
	 *
	 * @param \WP_Post $album  Album post.
	 * @param array    $tracks Track posts.
	 * @param string   $format Audio format.
	 * @return string|null ZIP file path or null on failure.
	 */
	private function create_album_zip( \WP_Post $album, array $tracks, string $format ): ?string {
		if ( ! class_exists( 'ZipArchive' ) ) {
			return null;
		}

		$temp_dir = get_temp_dir();
		$zip_path = $temp_dir . 'fedistream-album-' . $album->ID . '-' . time() . '.zip';

		$zip = new \ZipArchive();
		if ( $zip->open( $zip_path, \ZipArchive::CREATE ) !== true ) {
			return null;
		}

		$track_number = 0;
		foreach ( $tracks as $track ) {
			++$track_number;

			$audio_id = get_post_meta( $track->ID, '_fedistream_audio_file', true );
			if ( ! $audio_id ) {
				continue;
			}

			$file_path = get_attached_file( $audio_id );
			if ( ! $file_path || ! file_exists( $file_path ) ) {
				continue;
			}

			// Get converted file.
			$converted_file = $this->get_converted_file( $file_path, $format, $track->ID );

			// Create filename with track number.
			$filename = sprintf(
				'%02d - %s.%s',
				$track_number,
				sanitize_file_name( $track->post_title ),
				$format
			);

			$zip->addFile( $converted_file, $filename );
		}

		// Add cover art if available.
		$thumbnail_id = get_post_thumbnail_id( $album->ID );
		if ( $thumbnail_id ) {
			$cover_path = get_attached_file( $thumbnail_id );
			if ( $cover_path && file_exists( $cover_path ) ) {
				$cover_ext = pathinfo( $cover_path, PATHINFO_EXTENSION );
				$zip->addFile( $cover_path, 'cover.' . $cover_ext );
			}
		}

		$zip->close();

		return file_exists( $zip_path ) ? $zip_path : null;
	}

	/**
	 * Serve a file for download.
	 *
	 * @param string $file_path File path.
	 * @param string $filename  Download filename.
	 * @param string $format    File format.
	 * @return void
	 */
	private function serve_file( string $file_path, string $filename, string $format ): void {
		if ( ! file_exists( $file_path ) ) {
			wp_die( esc_html__( 'File not found.', 'wp-fedistream' ) );
		}

		// Get MIME type.
		$mime_types = array(
			'mp3'  => 'audio/mpeg',
			'flac' => 'audio/flac',
			'wav'  => 'audio/wav',
			'ogg'  => 'audio/ogg',
			'aac'  => 'audio/aac',
			'zip'  => 'application/zip',
		);

		$mime_type = $mime_types[ $format ] ?? 'application/octet-stream';

		// Clean output buffer.
		while ( ob_get_level() ) {
			ob_end_clean();
		}

		// Set headers.
		nocache_headers();
		header( 'Content-Type: ' . $mime_type );
		header( 'Content-Description: File Transfer' );
		header( 'Content-Disposition: attachment; filename="' . $filename . '"' );
		header( 'Content-Transfer-Encoding: binary' );
		header( 'Content-Length: ' . filesize( $file_path ) );

		// Read file.
		readfile( $file_path ); // phpcs:ignore WordPress.WP.AlternativeFunctions.file_system_operations_readfile

		exit;
	}

	/**
	 * Add download links to order confirmation email.
	 *
	 * @param \WC_Order $order         Order object.
	 * @param bool      $sent_to_admin Whether sent to admin.
	 * @param bool      $plain_text    Whether plain text.
	 * @param object    $email         Email object.
	 * @return void
	 */
	public function add_download_links_to_email( \WC_Order $order, bool $sent_to_admin, bool $plain_text, $email ): void {
		if ( $sent_to_admin || 'completed' !== $order->get_status() ) {
			return;
		}

		$has_fedistream = false;
		foreach ( $order->get_items() as $item ) {
			$product_type = \WC_Product_Factory::get_product_type( $item->get_product_id() );
			if ( in_array( $product_type, array( 'fedistream_album', 'fedistream_track' ), true ) ) {
				$has_fedistream = true;
				break;
			}
		}

		if ( ! $has_fedistream ) {
			return;
		}

		$downloads_url = wc_get_account_endpoint_url( 'downloads' );

		if ( $plain_text ) {
			echo "\n\n";
			echo esc_html__( 'Your FediStream Downloads', 'wp-fedistream' ) . "\n";
			echo esc_html__( 'Access your purchased music at:', 'wp-fedistream' ) . ' ' . esc_url( $downloads_url ) . "\n";
		} else {
			?>
			<h2><?php esc_html_e( 'Your FediStream Downloads', 'wp-fedistream' ); ?></h2>
			<p>
				<?php
				printf(
					/* translators: %s: Downloads URL */
					esc_html__( 'Access your purchased music in your %s.', 'wp-fedistream' ),
					'<a href="' . esc_url( $downloads_url ) . '">' . esc_html__( 'account downloads', 'wp-fedistream' ) . '</a>'
				);
				?>
			</p>
			<?php
		}
	}

	/**
	 * Customize downloads display in My Account.
	 *
	 * @return void
	 */
	public function customize_downloads_display(): void {
		if ( ! is_user_logged_in() ) {
			return;
		}

		$user_id   = get_current_user_id();
		$purchases = $this->get_user_purchases( $user_id );

		if ( empty( $purchases ) ) {
			return;
		}

		?>
		<h3><?php esc_html_e( 'FediStream Library', 'wp-fedistream' ); ?></h3>
		<table class="woocommerce-table shop_table shop_table_responsive">
			<thead>
				<tr>
					<th><?php esc_html_e( 'Title', 'wp-fedistream' ); ?></th>
					<th><?php esc_html_e( 'Type', 'wp-fedistream' ); ?></th>
					<th><?php esc_html_e( 'Purchased', 'wp-fedistream' ); ?></th>
					<th><?php esc_html_e( 'Download', 'wp-fedistream' ); ?></th>
				</tr>
			</thead>
			<tbody>
				<?php foreach ( $purchases as $purchase ) : ?>
					<?php
					$content = get_post( $purchase->content_id );
					if ( ! $content ) {
						continue;
					}

					$formats = array( 'mp3', 'flac' ); // Default formats.
					?>
					<tr>
						<td><?php echo esc_html( $content->post_title ); ?></td>
						<td><?php echo esc_html( ucfirst( $purchase->content_type ) ); ?></td>
						<td><?php echo esc_html( date_i18n( get_option( 'date_format' ), strtotime( $purchase->purchased_at ) ) ); ?></td>
						<td>
							<?php foreach ( $formats as $format ) : ?>
								<?php
								$download_url = add_query_arg(
									array(
										'fedistream_download' => $purchase->content_type,
										$purchase->content_type . '_id' => $purchase->content_id,
										'format'              => $format,
									),
									home_url( '/' )
								);
								?>
								<a href="<?php echo esc_url( $download_url ); ?>" class="button button-small">
									<?php echo esc_html( strtoupper( $format ) ); ?>
								</a>
							<?php endforeach; ?>
						</td>
					</tr>
				<?php endforeach; ?>
			</tbody>
		</table>
		<?php
	}

	/**
	 * Get user's purchases.
	 *
	 * @param int $user_id User ID.
	 * @return array
	 */
	private function get_user_purchases( int $user_id ): array {
		global $wpdb;

		$table = $wpdb->prefix . 'fedistream_purchases';

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching
		$purchases = $wpdb->get_results(
			$wpdb->prepare(
				"SELECT * FROM {$table} WHERE user_id = %d ORDER BY purchased_at DESC",
				$user_id
			)
		);

		return $purchases ?: array();
	}

	/**
	 * Force download for audio files.
	 *
	 * @param bool   $force Force download.
	 * @param string $file_path File path.
	 * @return bool
	 */
	public function force_download_for_audio( bool $force, string $file_path ): bool {
		$ext = strtolower( pathinfo( $file_path, PATHINFO_EXTENSION ) );

		$audio_extensions = array( 'mp3', 'wav', 'flac', 'ogg', 'aac', 'm4a' );

		if ( in_array( $ext, $audio_extensions, true ) ) {
			return true;
		}

		return $force;
	}
}