<?php
/**
 * Stand-alone /listen page: a full-window player with logo and share links,
 * served from templates/listen.php (override: yourtheme/streamsera/listen.php).
 *
 * Settings: listen_enabled, listen_slug (default "listen"), listen_player.
 *
 * @package StreamSera
 */

namespace StreamSera\Modules;

use StreamSera\Frontend\Assets;
use StreamSera\PostTypes\Player;
use StreamSera\PostTypes\Station;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * Listen_Page.
 */
class Listen_Page {

	const QUERY = 'streamsera_listen';

	/**
	 * Register.
	 */
	public function register() {
		add_action( 'init', array( $this, 'rewrite' ) );
		add_filter( 'query_vars', array( $this, 'query_vars' ) );
		add_action( 'template_redirect', array( $this, 'render' ) );
		add_filter( 'streamsera_save_settings', array( $this, 'save_settings' ), 5, 2 );
		add_filter( 'streamsera_admin_data', array( $this, 'admin_data' ) );
		add_action( 'wp_head', array( $this, 'head_link' ) );
	}

	/**
	 * Slug (sanitized, never empty).
	 *
	 * @return string
	 */
	public static function slug() {
		$slug = sanitize_title( (string) streamsera_get_setting( 'listen_slug', 'listen' ) );
		return $slug ? $slug : 'listen';
	}

	/**
	 * Whether the page is on.
	 *
	 * @return bool
	 */
	public static function enabled() {
		return (bool) streamsera_get_setting( 'listen_enabled', false );
	}

	/**
	 * Player used by the page (falls back to the first published player).
	 *
	 * @return int
	 */
	public static function player_id() {
		$id = (int) streamsera_get_setting( 'listen_player', 0 );
		if ( ! $id ) {
			$first = get_posts(
				array(
					'post_type'      => Player::POST_TYPE,
					'post_status'    => 'publish',
					'posts_per_page' => 1,
					'fields'         => 'ids',
				)
			);
			$id    = $first ? (int) $first[0] : 0;
		}
		return $id;
	}

	/**
	 * Public URL.
	 *
	 * @return string
	 */
	public static function url() {
		if ( get_option( 'permalink_structure' ) ) {
			return home_url( user_trailingslashit( self::slug() ) );
		}
		return add_query_arg( self::QUERY, '1', home_url( '/' ) );
	}

	/**
	 * Sections a listen page can show under the player (key → label). Core: the station switcher and
	 * share buttons; add-ons add theirs and render them on `streamsera_listen_page_section`.
	 *
	 * @return array
	 */
	public static function sections() {
		/**
		 * Filter the listen page sections.
		 *
		 * @param array $sections Key → label.
		 */
		return (array) apply_filters(
			'streamsera_listen_page_sections',
			array(
				'switcher' => __( 'Station switcher', 'streamsera' ),
				'share'    => __( 'Share buttons', 'streamsera' ),
			)
		);
	}

	/**
	 * Sections shown, in order. Sites from before the setting keep what the page always showed.
	 *
	 * @return string[]
	 */
	public static function active_sections() {
		$saved = streamsera_get_setting( 'listen_sections', null );
		$list  = is_array( $saved ) ? $saved : array( 'schedule', 'share' );
		return array_values( array_intersect( array_map( 'strval', $list ), array_keys( self::sections() ) ) );
	}

	/**
	 * Rewrite rule.
	 */
	public function rewrite() {
		if ( get_option( 'streamsera_flush_rewrite' ) ) {
			delete_option( 'streamsera_flush_rewrite' );
			add_action( 'wp_loaded', 'flush_rewrite_rules' );
		}
		// Only claim the slug while the page is on; otherwise a real page at /listen/ must keep working.
		if ( ! self::enabled() ) {
			return;
		}
		add_rewrite_rule( '^' . preg_quote( self::slug(), '/' ) . '/?$', 'index.php?' . self::QUERY . '=1', 'top' );
	}

	/**
	 * Query var.
	 *
	 * @param array $vars Vars.
	 * @return array
	 */
	public function query_vars( $vars ) {
		$vars[] = self::QUERY;
		return $vars;
	}

	/**
	 * Persist the new keys; flush rewrites when the slug changes.
	 *
	 * @param array $next  Settings about to be saved.
	 * @param array $input Raw input.
	 * @return array
	 */
	public function save_settings( $next, $input ) {
		$current = (array) get_option( 'streamsera_settings', array() );
		if ( isset( $input['listen_slug'] ) && is_scalar( $input['listen_slug'] ) ) {
			$slug     = sanitize_title( (string) ( $next['listen_slug'] ?? $input['listen_slug'] ) );
			$slug     = $slug ? $slug : 'listen';
			$previous = sanitize_title( (string) ( $current['listen_slug'] ?? 'listen' ) );
			$previous = $previous ? $previous : 'listen';
			$conflict = $slug !== $previous ? streamsera_slug_conflict( $slug, 'listen_slug' ) : '';
			if ( $conflict ) {
				// A rewrite on this slug would hijack existing content: keep the old value and say why.
				streamsera_add_settings_error(
					'listen_slug',
					sprintf( /* translators: 1: slug, 2: what already uses it */ __( '"/%1$s/" is already used by %2$s. The listen page slug was not changed.', 'streamsera' ), $slug, $conflict )
				);
				$slug = $previous;
			}
			$next['listen_slug'] = $slug;
		}
		streamsera_guard_page_enable(
			$next,
			$current,
			'listen_enabled',
			'listen_slug',
			'listen',
			/* translators: 1: slug, 2: what already uses it */
			__( '"/%1$s/" is already used by %2$s, so the listen page was not turned on. Change the listen page slug first.', 'streamsera' )
		);
		if ( array_key_exists( 'listen_sections', $input ) && is_array( $input['listen_sections'] ) ) {
			// Keys only; unknown ones are kept so an add-on's section survives while it is inactive.
			$keys                    = array_map( 'sanitize_key', array_filter( $input['listen_sections'], 'is_scalar' ) );
			$next['listen_sections'] = array_values( array_unique( array_filter( $keys ) ) );
		}
		if ( ( $current['listen_slug'] ?? 'listen' ) !== ( $next['listen_slug'] ?? 'listen' ) || (bool) ( $next['listen_enabled'] ?? false ) !== (bool) ( $current['listen_enabled'] ?? false ) ) {
			update_option( 'streamsera_flush_rewrite', 1, false );
		}
		return $next;
	}

	/**
	 * Expose the URL to the admin app.
	 *
	 * @param array $data Admin data.
	 * @return array
	 */
	public function admin_data( $data ) {
		$data['listenUrl']  = self::url();
		$data['homeUrl']    = home_url( '/' );
		$data['permalinks'] = (bool) get_option( 'permalink_structure' );
		$sections           = array();
		foreach ( self::sections() as $key => $label ) {
			$sections[] = array(
				'key'   => (string) $key,
				'label' => (string) $label,
			);
		}
		$data['listenSections']       = $sections;
		$data['listenSectionsActive'] = self::active_sections();
		$data['blockTheme']           = function_exists( 'wp_is_block_theme' ) && wp_is_block_theme();
		return $data;
	}

	/**
	 * Stations for the listen page's switcher: every published station, current one first marked.
	 *
	 * @param int $current Station on the page now.
	 * @return array[] { id, name, logo, url, current }
	 */
	public static function switcher_stations( $current ) {
		$ids = get_posts(
			array(
				'post_type'      => Station::POST_TYPE,
				'post_status'    => 'publish',
				'posts_per_page' => 30,
				'orderby'        => array(
					'menu_order' => 'ASC',
					'title'      => 'ASC',
				),
				'fields'         => 'ids',
			)
		);
		$out = array();
		foreach ( $ids as $id ) {
			$public = Station::to_public( (int) $id );
			if ( ! $public ) {
				continue;
			}
			$out[] = array(
				'id'      => (int) $id,
				'name'    => (string) $public['name'],
				'logo'    => (string) ( $public['logo'] ?? '' ),
				'url'     => add_query_arg( 'station', (int) $id, self::url() ),
				'current' => (int) $id === (int) $current,
			);
		}
		return count( $out ) > 1 ? $out : array();
	}

	/**
	 * Advertise the listen page (lets browsers/apps discover it).
	 */
	public function head_link() {
		if ( self::enabled() && self::player_id() ) {
			echo '<link rel="alternate" type="text/html" title="' . esc_attr__( 'Listen live', 'streamsera' ) . '" href="' . esc_url( self::url() ) . '" class="streamsera-listen-link">' . "\n";
		}
	}

	/**
	 * Serve the page.
	 */
	public function render() {
		if ( ! get_query_var( self::QUERY ) ) {
			return;
		}
		if ( ! self::enabled() ) {
			return; // Falls through to the theme's 404.
		}
		$player_id = self::player_id();
		$config    = $player_id ? Player::get_config( $player_id ) : null;
		if ( ! $config ) {
			return;
		}
		$config = Player::with_live_station( $config );
		// Station switcher: ?station=ID plays another published station with the same player.
		$pick = isset( $_GET['station'] ) ? absint( wp_unslash( $_GET['station'] ) ) : 0; // phpcs:ignore WordPress.Security.NonceVerification.Recommended -- public, read-only.
		if ( $pick && $pick !== (int) $config['station'] && Station::to_public( $pick ) ) {
			$config['station'] = $pick;
		}
		$station = Station::to_public( $config['station'] );
		if ( ! $station ) {
			return;
		}
		// template_redirect runs before wp_enqueue_scripts: register exactly the player handles
		// (core + add-ons) so the template's head/footer have something to print.
		Assets::register_standalone();
		$markup = Assets::render_player(
			$player_id,
			array(
				'layout'  => 'hero',
				'station' => (int) $config['station'],
			),
			array( 'listen' => true )
		);
		if ( ! $markup ) {
			return;
		}
		$vars = array(
			'player_id' => $player_id,
			'config'    => $config,
			'station'   => $station,
			'markup'    => $markup,
			'url'       => self::url(),
			'site'      => get_bloginfo( 'name' ),
			'title'     => sprintf( /* translators: %s station name */ __( 'Listen live — %s', 'streamsera' ), $station['name'] ),
			'back'      => home_url( '/' ),
			'sections'  => self::active_sections(),
			'stations'  => in_array( 'switcher', self::active_sections(), true ) ? self::switcher_stations( (int) $station['id'] ) : array(),
			'share'     => array(
				'x'        => 'https://twitter.com/intent/tweet?' . http_build_query(
					array(
						'text' => sprintf( /* translators: %s station */ __( 'Listening to %s', 'streamsera' ), $station['name'] ),
						'url'  => self::url(),
					)
				),
				'facebook' => 'https://www.facebook.com/sharer/sharer.php?u=' . rawurlencode( self::url() ),
				'whatsapp' => 'https://wa.me/?text=' . rawurlencode( $station['name'] . ' ' . self::url() ),
			),
		);
		/**
		 * Filter the variables handed to the listen template.
		 *
		 * @param array $vars Vars.
		 */
		$vars = apply_filters( 'streamsera_listen_vars', $vars );

		$file = locate_template( array( 'streamsera/listen.php' ) );
		if ( ! $file ) {
			$file = STREAMSERA_PATH . 'templates/listen.php';
		}
		/**
		 * Filter the listen page template path.
		 *
		 * @param string $file Template.
		 */
		$file = streamsera_safe_template( apply_filters( 'streamsera_listen_template', $file ), STREAMSERA_PATH . 'templates/listen.php' );

		nocache_headers();
		status_header( 200 );
		header( 'Content-Type: text/html; charset=utf-8' );
		$streamsera = $vars; // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
		include $file;
		exit;
	}
}