<?php
/**
 * Register Dadan as an oEmbed provider and sanitize remote HTML (SEC-05).
 *
 * @package Dadan_Video
 */

defined( 'ABSPATH' ) || exit;

/**
 * oEmbed provider registration and HTML rebuild.
 */
class Dadan_OEmbed {

	/**
	 * Register hooks.
	 */
	public function register() {
		// Do NOT register the remote oEmbed provider while /api/oembed returns
		// {success:false} — WordPress treats that JSON as valid data and the
		// Gutenberg Embed block never falls through to our handler.
		add_action( 'init', array( $this, 'register_embed_handler' ) );
		add_filter( 'pre_oembed_result', array( $this, 'filter_pre_oembed_result' ), 10, 3 );
		add_filter( 'oembed_result', array( $this, 'filter_oembed_result' ), 10, 3 );
		add_filter( 'oembed_dataparse', array( $this, 'filter_oembed_dataparse' ), 10, 3 );
		add_filter( 'embed_oembed_html', array( $this, 'filter_embed_oembed_html' ), 10, 4 );
		add_filter( 'embed_maybe_make_link', array( $this, 'filter_embed_maybe_make_link' ), 10, 2 );
	}

	/**
	 * Classic embed handler — used by REST oEmbed proxy when remote get_data fails.
	 */
	public function register_embed_handler() {
		// phpcs:ignore WordPress.WP.CapitalPDangit.MisspelledInText -- regex not prose.
		wp_embed_register_handler(
			'dadan',
			'#https?://(?:www\.)?(?:app\.)?dadan\.(?:io|video)/(?:video/share/|video/embed\.html|(?:share|watch|embed)/)[^\s]*#i',
			array( $this, 'embed_handler' )
		);
	}

	/**
	 * Render iframe for classic embed / REST proxy fallback.
	 *
	 * @param array  $matches Regex matches.
	 * @param array  $attr    Embed attributes.
	 * @param string $url     Source URL.
	 * @param array  $rawattr Raw attributes.
	 * @return string
	 */
	public function embed_handler( $matches, $attr, $url, $rawattr ) {
		unset( $matches );

		// DADAN-18: only honour an author-supplied height in $rawattr.
		// WP's default height is 1.5×width (portrait) — never use $attr['height'].
		$width = isset( $attr['width'] ) ? absint( $attr['width'] ) : 640;
		if ( is_array( $rawattr ) && isset( $rawattr['width'] ) ) {
			$width = absint( $rawattr['width'] );
		}
		$height = 0;
		if ( is_array( $rawattr ) && isset( $rawattr['height'] ) ) {
			$height = absint( $rawattr['height'] );
		}

		$html = Dadan_Fallback::render_from_url( $url, $width, $height );
		return '' !== $html ? $html : '';
	}

	/**
	 * Return a local iframe for Dadan URLs before WordPress hits the remote API.
	 *
	 * @param null|string  $result Unused prior result.
	 * @param string       $url    URL being embedded.
	 * @param string|array $args   oEmbed args.
	 * @return string|false|null
	 */
	public function filter_pre_oembed_result( $result, $url, $args ) {
		if ( ! Dadan_Url::is_dadan_url( $url ) ) {
			return $result;
		}

		$parsed = Dadan_Url::parse( $url );
		// Direct /video/{id} cannot build embed.html?link= — fail closed (use share URL).
		if ( $parsed && 'video' === $parsed['kind'] ) {
			return false;
		}

		$html = Dadan_Fallback::render_from_url(
			$url,
			$this->args_width( $args ),
			$this->args_height( $args )
		);
		return '' !== $html ? $html : $result;
	}

	/**
	 * Ensure oEmbed HTML is always our local iframe (REST proxy path).
	 *
	 * @param string|false $html Remote/derived HTML.
	 * @param string       $url  Source URL.
	 * @param string|array $args Args.
	 * @return string|false
	 */
	public function filter_oembed_result( $html, $url, $args ) {
		if ( ! Dadan_Url::is_dadan_url( $url ) ) {
			return $html;
		}

		$local = Dadan_Fallback::render_from_url(
			$url,
			$this->args_width( $args ),
			$this->args_height( $args )
		);
		return '' !== $local ? $local : $html;
	}

	/**
	 * @param string|array $args oEmbed args.
	 * @return int
	 */
	private function args_width( $args ) {
		if ( is_array( $args ) ) {
			if ( ! empty( $args['width'] ) ) {
				return absint( $args['width'] );
			}
			if ( ! empty( $args['maxwidth'] ) ) {
				return absint( $args['maxwidth'] );
			}
		}
		return 640;
	}

	/**
	 * @param string|array $args oEmbed args.
	 * @return int
	 */
	private function args_height( $args ) {
		unset( $args );
		// DADAN-18: WP fills height/maxheight with 1.5×width for auto-embeds.
		// Pass 0 so Dadan_Fallback uses 16:9.
		return 0;
	}

	/**
	 * Replace remote oEmbed HTML with a locally built iframe when the URL is Dadan.
	 *
	 * @param string $result The oEmbed HTML result.
	 * @param object $data   A data object result from the oEmbed provider.
	 * @param string $url    The URL passed to the oEmbed provider.
	 * @return string
	 */
	public function filter_oembed_dataparse( $result, $data, $url ) {
		if ( ! Dadan_Url::is_dadan_url( $url ) ) {
			return $result;
		}

		$width  = 640;
		$height = 360;
		$title  = '';

		if ( is_object( $data ) ) {
			if ( isset( $data->width ) && is_numeric( $data->width ) ) {
				$width = (int) $data->width;
			}
			if ( isset( $data->height ) && is_numeric( $data->height ) ) {
				$height = (int) $data->height;
			}
			if ( ! empty( $data->title ) && is_string( $data->title ) ) {
				$title = $data->title;
			}
		}

		$html = Dadan_Fallback::render_from_url( $url, $width, $height, $title );
		return '' !== $html ? $html : $result;
	}

	/**
	 * Last-resort sanitize of cached/embed HTML for Dadan URLs.
	 *
	 * @param string|false $cached_html The cached HTML result, stored in post meta.
	 * @param string       $url         The attempted embed URL.
	 * @param array        $attr        An array of shortcode attributes.
	 * @param int          $post_id     Post ID.
	 * @return string|false
	 */
	public function filter_embed_oembed_html( $cached_html, $url, $attr, $post_id ) {
		unset( $post_id );

		if ( ! Dadan_Url::is_dadan_url( $url ) ) {
			return $cached_html;
		}

		$width = isset( $attr['width'] ) ? absint( $attr['width'] ) : 640;
		// DADAN-18: $attr height is WP's portrait default — ignore; use 16:9.
		$height = 0;

		$html = Dadan_Fallback::render_from_url( $url, $width, $height );
		if ( '' !== $html ) {
			return $html;
		}

		return $cached_html;
	}

	/**
	 * When remote oEmbed fails, WP falls back to a link — replace with local iframe.
	 *
	 * @param string $output Default link HTML.
	 * @param string $url    Attempted embed URL.
	 * @return string
	 */
	public function filter_embed_maybe_make_link( $output, $url ) {
		if ( ! Dadan_Url::is_dadan_url( $url ) ) {
			return $output;
		}

		$html = Dadan_Fallback::render_from_url( $url );
		return '' !== $html ? $html : $output;
	}
}