<?php
/**
 * REST routes used by the admin screen and the transcript block.
 *
 * @package Captionwright
 */

namespace Captionwright;

defined( 'ABSPATH' ) || exit;

add_action( 'rest_api_init', __NAMESPACE__ . '\\register_routes' );

/**
 * Register routes under captionwright/v1.
 */
function register_routes() {
	register_rest_route(
		'captionwright/v1',
		'/media',
		array(
			'methods'             => 'GET',
			'callback'            => __NAMESPACE__ . '\\rest_list',
			'permission_callback' => function () {
				return current_user_can( 'upload_files' );
			},
		)
	);

	$can_edit = function ( \WP_REST_Request $req ) {
		$id = (int) $req['id'];
		return current_user_can( 'upload_files' ) && current_user_can( 'edit_post', $id );
	};

	register_rest_route(
		'captionwright/v1',
		'/media/(?P<id>\d+)/tracks',
		array(
			'methods'             => 'POST',
			'callback'            => __NAMESPACE__ . '\\rest_save',
			'permission_callback' => $can_edit,
			'args'                => array(
				'lang'  => array(
					'type'     => 'string',
					'required' => true,
				),
				'label' => array( 'type' => 'string' ),
				'vtt'   => array(
					'type'     => 'string',
					'required' => true,
				),
			),
		)
	);

	register_rest_route(
		'captionwright/v1',
		'/media/(?P<id>\d+)/tracks/(?P<lang>[a-z0-9-]+)',
		array(
			array(
				'methods'             => 'GET',
				'callback'            => __NAMESPACE__ . '\\rest_read',
				'permission_callback' => $can_edit,
			),
			array(
				'methods'             => 'DELETE',
				'callback'            => __NAMESPACE__ . '\\rest_delete',
				'permission_callback' => $can_edit,
			),
		)
	);
}

/**
 * Check the attachment is audio or video.
 *
 * @param int $id Attachment ID.
 * @return bool
 */
function is_media( $id ) {
	$mime = (string) get_post_mime_type( (int) $id );
	$ok   = 'attachment' === get_post_type( (int) $id ) && ( 0 === strpos( $mime, 'video/' ) || 0 === strpos( $mime, 'audio/' ) );
	/**
	 * Filters whether a post can hold caption tracks.
	 *
	 * @param bool $ok Whether it is an audio/video attachment.
	 * @param int  $id Post ID.
	 */
	return (bool) apply_filters( 'captionwright_is_captionable', $ok, (int) $id );
}

/**
 * List audio/video attachments (optionally only captioned ones).
 *
 * @param \WP_REST_Request $req Request.
 * @return \WP_REST_Response
 */
function rest_list( \WP_REST_Request $req ) {
	$args = array(
		'post_type'      => 'attachment',
		'post_status'    => 'inherit',
		'post_mime_type' => array( 'video', 'audio' ),
		'posts_per_page' => 100,
		'paged'          => max( 1, (int) $req->get_param( 'page' ) ),
		'orderby'        => 'date',
		'order'          => 'DESC',
	);
	if ( $req->get_param( 'captioned' ) ) {
		$args['meta_key'] = META; // phpcs:ignore WordPress.DB.SlowDBQuery.slow_db_query_meta_key -- small, admin-only list.
	}
	$out = array();
	foreach ( get_posts( $args ) as $p ) {
		$out[] = array(
			'id'     => $p->ID,
			'title'  => get_the_title( $p ),
			'mime'   => $p->post_mime_type,
			'url'    => wp_get_attachment_url( $p->ID ),
			'tracks' => get_tracks( $p->ID ),
		);
	}
	/**
	 * Filters the media list (add-ons can add other captioned sources).
	 *
	 * @param array            $out List.
	 * @param \WP_REST_Request $req Request.
	 */
	return rest_ensure_response( apply_filters( 'captionwright_media_list', $out, $req ) );
}

/**
 * Save a caption track.
 *
 * @param \WP_REST_Request $req Request.
 * @return \WP_REST_Response|\WP_Error
 */
function rest_save( \WP_REST_Request $req ) {
	$id   = (int) $req['id'];
	$lang = strtolower( (string) $req['lang'] );
	if ( ! is_media( $id ) ) {
		return new \WP_Error( 'captionwright_not_media', __( 'That file is not audio or video.', 'captionwright' ), array( 'status' => 404 ) );
	}
	if ( ! valid_lang( $lang ) ) {
		return new \WP_Error( 'captionwright_lang', __( 'Invalid language code.', 'captionwright' ), array( 'status' => 400 ) );
	}
	$vtt = clean_vtt( (string) $req['vtt'] );
	if ( is_wp_error( $vtt ) ) {
		return $vtt;
	}
	$label = sanitize_text_field( (string) $req['label'] );
	$saved = save_track( $id, $lang, $vtt, '' !== $label ? $label : $lang );
	if ( is_wp_error( $saved ) ) {
		return $saved;
	}
	return rest_ensure_response( array( 'tracks' => get_tracks( $id ) ) );
}

/**
 * Return a track's WebVTT text for editing.
 *
 * @param \WP_REST_Request $req Request.
 * @return \WP_REST_Response|\WP_Error
 */
function rest_read( \WP_REST_Request $req ) {
	$vtt = read_track( (int) $req['id'], (string) $req['lang'] );
	if ( '' === $vtt ) {
		return new \WP_Error( 'captionwright_missing', __( 'No captions saved in that language.', 'captionwright' ), array( 'status' => 404 ) );
	}
	return rest_ensure_response( array( 'vtt' => $vtt ) );
}

/**
 * Delete a caption track.
 *
 * @param \WP_REST_Request $req Request.
 * @return \WP_REST_Response
 */
function rest_delete( \WP_REST_Request $req ) {
	delete_track( (int) $req['id'], (string) $req['lang'] );
	return rest_ensure_response( array( 'tracks' => get_tracks( (int) $req['id'] ) ) );
}