<?php
/**
 * Dadan URL parsing — production app.dadan.io /video/* patterns.
 *
 * @package Dadan_Video
 */

defined( 'ABSPATH' ) || exit;

/**
 * Parse and validate Dadan share / video / embed URLs.
 */
class Dadan_Url {

	/**
	 * Production share: https://app.dadan.io/video/share/{code}
	 *
	 * @var string
	 */
	const VIDEO_SHARE_PATTERN = '#^(?:https?://)?(?:www\.)?(?:app\.)?dadan\.(?:io|video)/video/share/([A-Za-z0-9_-]{1,128})(?:/?(?:[?\#].*)?)?$#i';

	/**
	 * Production watch-by-id: https://app.dadan.io/video/{id}
	 * (not a share code — embed requires a share link).
	 * Negative lookahead skips /video/share/ and /video/embed.html.
	 *
	 * @var string
	 */
	const VIDEO_ID_PATTERN = '#^(?:https?://)?(?:www\.)?(?:app\.)?dadan\.(?:io|video)/video/(?!share(?:/|$)|embed\.html)([A-Za-z0-9_-]{1,128})/?$#i';

	/**
	 * Production embed player: .../video/embed.html?...&link={code}
	 *
	 * @var string
	 */
	const VIDEO_EMBED_HTML_PATTERN = '#^(?:https?://)?(?:www\.)?(?:app\.)?dadan\.(?:io|video)/video/embed\.html#i';

	/**
	 * Legacy SDK-style paths (still accepted if present).
	 *
	 * @var string
	 */
	const LEGACY_SHARE_PATTERN = '#^(?:https?://)?(?:www\.)?(?:app\.)?dadan\.(?:io|video)/(?:share|watch)/([A-Za-z0-9_-]{1,128})(?:/?(?:[?\#].*)?)?$#i';

	/**
	 * Legacy SDK embed path.
	 *
	 * @var string
	 */
	const LEGACY_EMBED_PATTERN = '#^(?:https?://)?(?:www\.)?(?:app\.)?dadan\.(?:io|video)/embed/([A-Za-z0-9_-]{1,128})(?:/?(?:[?\#].*)?)?$#i';

	/**
	 * Pattern for wp_oembed_add_provider (regex with # delimiters).
	 *
	 * @var string
	 */
	const OEMBED_PROVIDER_REGEX = '#https?://(?:www\.)?(?:app\.)?dadan\.(?:io|video)/(?:video/(?:share/|embed\.html)|(?:share|watch|embed)/)[^\s]*#i';

	/**
	 * Default query flags for embed.html (match Dadan share → embed UI).
	 *
	 * @var array<string, string>
	 */
	const EMBED_DEFAULT_PARAMS = array(
		'hide_emojies'         => 'false',
		'hide_interactions'    => 'false',
		'hide_comments'        => 'false',
		'hide_owner'           => 'false',
		'hide_analytics'       => 'false',
		'hide_watch_on_dadan'  => 'false',
		'hide_chapters'        => 'false',
	);

	/**
	 * Parse a Dadan URL.
	 *
	 * @param string $url Raw URL or bare share code.
	 * @return array{id: string, kind: string}|null kind: share|video|embed
	 */
	public static function parse( $url ) {
		$url = trim( (string) $url );
		if ( '' === $url ) {
			return null;
		}

		if ( preg_match( self::VIDEO_SHARE_PATTERN, $url, $m ) && ! empty( $m[1] ) ) {
			return array(
				'id'   => $m[1],
				'kind' => 'share',
			);
		}

		if ( preg_match( self::VIDEO_EMBED_HTML_PATTERN, $url ) ) {
			$parts = wp_parse_url( $url );
			if ( ! empty( $parts['query'] ) ) {
				parse_str( $parts['query'], $query );
				// DADAN-06: ?link[]= makes link an array; preg_match TypeErrors on PHP 8+.
				$link = isset( $query['link'] ) && is_string( $query['link'] ) ? $query['link'] : '';
				if ( '' !== $link && preg_match( '/^[A-Za-z0-9_-]{1,64}$/', $link ) ) {
					return array(
						'id'   => $link,
						'kind' => 'embed',
					);
				}
			}
			return null;
		}

		if ( preg_match( self::VIDEO_ID_PATTERN, $url, $m ) && ! empty( $m[1] ) ) {
			return array(
				'id'   => $m[1],
				'kind' => 'video',
			);
		}

		if ( preg_match( self::LEGACY_SHARE_PATTERN, $url, $m ) && ! empty( $m[1] ) ) {
			return array(
				'id'   => $m[1],
				'kind' => 'share',
			);
		}

		if ( preg_match( self::LEGACY_EMBED_PATTERN, $url, $m ) && ! empty( $m[1] ) ) {
			return array(
				'id'   => $m[1],
				'kind' => 'embed',
			);
		}

		// DADAN-40: cap bare share-code length (same bound as embed ?link=).
		if ( preg_match( '/^[A-Za-z0-9_-]{1,128}$/', $url ) ) {
			return array(
				'id'   => $url,
				'kind' => 'share',
			);
		}

		return null;
	}

	/**
	 * Whether the URL is a recognized Dadan video URL (full URL, not bare id).
	 *
	 * @param string $url URL to test.
	 * @return bool
	 */
	public static function is_dadan_url( $url ) {
		$url = trim( (string) $url );
		if ( '' === $url ) {
			return false;
		}

		if ( preg_match( self::VIDEO_SHARE_PATTERN, $url ) ) {
			return true;
		}
		if ( preg_match( self::VIDEO_EMBED_HTML_PATTERN, $url ) ) {
			$parsed = self::parse( $url );
			return null !== $parsed;
		}
		if ( preg_match( self::VIDEO_ID_PATTERN, $url ) ) {
			return true;
		}
		if ( preg_match( self::LEGACY_SHARE_PATTERN, $url ) ) {
			return true;
		}
		if ( preg_match( self::LEGACY_EMBED_PATTERN, $url ) ) {
			return true;
		}

		return false;
	}

	/**
	 * Whether this URL can be turned into an embed iframe (needs a share `link` code).
	 *
	 * @param string $url Dadan URL.
	 * @return bool
	 */
	public static function can_embed( $url ) {
		$parsed = self::parse( $url );
		if ( ! $parsed ) {
			return false;
		}
		// Direct /video/{hex} pages need a share link for embed.html?link=.
		return 'video' !== $parsed['kind'];
	}

	/**
	 * Build canonical player URL:
	 * https://app.dadan.io/video/embed.html?...&link={shareCode}
	 *
	 * @param string $shared_url Share / embed URL, or bare share code.
	 * @return string|null
	 */
	public static function to_embed_url( $shared_url ) {
		$parsed = self::parse( $shared_url );
		if ( ! $parsed || 'video' === $parsed['kind'] ) {
			return null;
		}

		$base   = rtrim( DADAN_API_BASE, '/' ) . '/video/embed.html';
		$params = self::EMBED_DEFAULT_PARAMS;
		$params['link'] = $parsed['id'];

		return $base . '?' . http_build_query( $params, '', '&', PHP_QUERY_RFC3986 );
	}

	/**
	 * Sanitize width attribute (pixels).
	 *
	 * @param mixed $width Width value.
	 * @param int   $default Default if invalid.
	 * @return int
	 */
	public static function sanitize_dimension( $width, $default = 640 ) {
		$width = absint( $width );
		if ( $width < 100 ) {
			return (int) $default;
		}
		if ( $width > 2560 ) {
			return 2560;
		}
		return $width;
	}
}