<?php
/**
 * Callbacks for adding AMP-related things to the admin.
 *
 * @package AMP
 */

/**
 * Obsolete constant for flagging when Customizer is opened for AMP.
 *
 * @deprecated
 * @var string
 */
define( 'AMP_CUSTOMIZER_QUERY_VAR', 'customize_amp' );

/**
 * Sets up the AMP template editor for the Customizer.
 */
function amp_init_customizer() {
	// Fire up the AMP Customizer.
	add_action( 'customize_register', array( 'AMP_Template_Customizer', 'init' ), 500 );

	// Add some basic design settings + controls to the Customizer.
	add_action( 'amp_init', array( 'AMP_Customizer_Design_Settings', 'init' ) );

	// Add a link to the Customizer.
	add_action( 'admin_menu', 'amp_add_customizer_link' );
}

/**
 * Get permalink for the first AMP-eligible post.
 *
 * @return string|null
 */
function amp_admin_get_preview_permalink() {
	/**
	 * Filter the post type to retrieve the latest for use in the AMP template customizer.
	 *
	 * @param string $post_type Post type slug. Default 'post'.
	 */
	$post_type = (string) apply_filters( 'amp_customizer_post_type', 'post' );

	if ( ! post_type_supports( $post_type, AMP_QUERY_VAR ) ) {
		return null;
	}

	$post_ids = get_posts( array(
		'post_status'    => 'publish',
		'post_password'  => '',
		'post_type'      => $post_type,
		'posts_per_page' => 1,
		'fields'         => 'ids',
	) );

	if ( empty( $post_ids ) ) {
		return false;
	}

	$post_id = $post_ids[0];

	return amp_get_permalink( $post_id );
}

/**
 * Registers a submenu page to access the AMP template editor panel in the Customizer.
 */
function amp_add_customizer_link() {
	$menu_slug = add_query_arg( array(
		'autofocus[panel]' => AMP_Template_Customizer::PANEL_ID,
		'url'              => rawurlencode( amp_admin_get_preview_permalink() ),
		'return'           => rawurlencode( admin_url() ),
	), 'customize.php' );

	// Add the theme page.
	add_theme_page(
		__( 'AMP', 'amp' ),
		__( 'AMP', 'amp' ),
		'edit_theme_options',
		$menu_slug
	);
}

/**
 * Registers AMP settings.
 */
function amp_add_options_menu() {
	if ( ! is_admin() ) {
		return;
	}

	/**
	 * Filter whether to enable the AMP settings.
	 *
	 * @since 0.5
	 * @param bool $enable Whether to enable the AMP settings. Default true.
	 */
	$short_circuit = apply_filters( 'amp_options_menu_is_enabled', true );

	if ( true !== $short_circuit ) {
		return;
	}

	$amp_options = new AMP_Options_Menu();
	$amp_options->init();
}

/**
 * Add custom analytics.
 *
 * @param array $analytics Analytics.
 * @return array Analytics.
 */
function amp_add_custom_analytics( $analytics ) {
	$analytics_entries = AMP_Options_Manager::get_option( 'analytics', array() );

	if ( ! $analytics_entries ) {
		return $analytics;
	}

	foreach ( $analytics_entries as $entry_id => $entry ) {
		$analytics[ $entry_id ] = array(
			'type' => $entry['type'],
			'attributes' => array(),
			'config_data' => json_decode( $entry['config'] ),
		);
	}

	return $analytics;
}

/**
 * Bootstrap AMP post meta box.
 *
 * This function must be invoked only once through the 'wp_loaded' action.
 *
 * @since 0.6
 */
function amp_post_meta_box() {
	$post_meta_box = new AMP_Post_Meta_Box();
	$post_meta_box->init();
}