<?php
/**
 * Public API for themes and other plugins (Facade): small, stable blocklingo_*
 * functions over the plugin services. Names and return shapes are part of
 * the public contract; new code inside the plugin uses the services.
 * Arguments are cast, so theme code may pass a post ID as a string.
 *
 * Each call runs through Failsafe::call(): when the plugin could not start or
 * hits an error, a theme that calls these gets an empty answer instead of a
 * broken page.
 */

declare( strict_types = 1 );

defined( 'ABSPATH' ) || exit;

use AddBlack\Lang\Failsafe;
use AddBlack\Lang\Plugin;

/**
 * Site languages in the saved order.
 *
 * @return array<string, array{code: string, slug: string, name: string, locale: string, flag: string, rtl: int}> code => language
 */
function blocklingo_languages(): array {
	return Failsafe::call(
		static fn(): array => array_map(
			static fn( \AddBlack\Lang\Language\Language $lang ): array => $lang->to_array(),
			Plugin::instance()->settings()->get()->languages()
		),
		array(),
		__FUNCTION__
	);
}

/** Code of the default language (no URL prefix). */
function blocklingo_default_lang(): string {
	return Failsafe::call( static fn(): string => Plugin::instance()->settings()->get()->default_code(), '', __FUNCTION__ );
}

/** Language of the current request. */
function blocklingo_current_lang(): string {
	return Failsafe::call( static fn(): string => Plugin::instance()->current_language()->get(), '', __FUNCTION__ );
}

function blocklingo_is_language( mixed $code ): bool {
	return Failsafe::call( static fn(): bool => Plugin::instance()->settings()->get()->is_language( $code ), false, __FUNCTION__ );
}

function blocklingo_is_translatable_type( mixed $post_type ): bool {
	return Failsafe::call( static fn(): bool => Plugin::instance()->settings()->get()->is_translatable_type( (string) $post_type ), false, __FUNCTION__ );
}

/** Language code of a post (default language when untagged). */
function blocklingo_get_post_lang( mixed $post_id ): string {
	return Failsafe::call( static fn(): string => Plugin::instance()->posts()->language_of( (int) $post_id ), '', __FUNCTION__ );
}

function blocklingo_set_post_lang( mixed $post_id, mixed $lang ): bool|WP_Error {
	if ( ! blocklingo_is_language( $lang ) ) {
		return new WP_Error( 'blocklingo_bad_lang', __( 'Unknown language.', 'blocklingo' ) );
	}
	return Failsafe::call( static fn(): bool|WP_Error => Plugin::instance()->translations()->assign( (int) $post_id, (string) $lang ), false, __FUNCTION__ );
}

/** @return array<string, int> lang => post ID, the post itself included. */
function blocklingo_get_post_translations( mixed $post_id ): array {
	return Failsafe::call( static fn(): array => Plugin::instance()->posts()->group( (int) $post_id ), array(), __FUNCTION__ );
}

/** Post ID of the translation in $lang, or 0. */
function blocklingo_get_post_translation( mixed $post_id, mixed $lang ): int {
	return Failsafe::call( static fn(): int => Plugin::instance()->posts()->in_language( (int) $post_id, (string) $lang ), 0, __FUNCTION__ );
}

/**
 * Language switcher for classic themes and PHP templates.
 *
 * @param array<string, mixed> $args display, hideCurrent, hideMissing (as in the block).
 */
function blocklingo_language_switcher( array $args = array() ): void {
	$html         = Failsafe::call( static fn(): string => Plugin::instance()->switcher()->render( $args ), '', __FUNCTION__ );
	$allowed      = wp_kses_allowed_html( 'post' );
	$allowed['a'] = array_merge( $allowed['a'] ?? array(), array( 'hreflang' => true ) ); // wp_kses_post() drops hreflang.
	echo wp_kses( $html, $allowed );
}