<?php
/**
 * How much of the site exists in a language: published content of the
 * default language with and without a version in it, per post type, and
 * the header/footer copies. Feeds the settings Overview and "Translate
 * the whole site".
 */

declare( strict_types = 1 );

namespace AddBlack\Lang\Translation;

defined( 'ABSPATH' ) || exit;

use AddBlack\Lang\Parts\TemplateParts;
use AddBlack\Lang\Settings\SettingsRepository;
use WP_Post;

final class Coverage {

	/** Most posts the bulk run lists at once. Counting has no limit. */
	public const LIMIT = 2000;

	public function __construct(
		private readonly SettingsRepository $settings,
		private readonly TranslationRepository $translations,
		private readonly TemplateParts $parts
	) {}

	/**
	 * Counted in the database, one query per language, so the Overview stays
	 * fast on sites with thousands of posts.
	 *
	 * @return array{total: int, done: int, types: array<string, array{label: string, total: int, done: int}>, parts: array<int, array{slug: string, title: string, exists: bool}>}
	 */
	public function summary( string $lang ): array {
		$out      = array(
			'total' => 0,
			'done'  => 0,
			'types' => array(),
			'parts' => $this->parts_status( $lang ),
		);
		$settings = $this->settings->get();
		$counts   = $this->translations->coverage_counts( $settings->post_types(), $settings->default_code(), $lang );
		ksort( $counts ); // page, portfolio, post: pages first.
		foreach ( $counts as $post_type => $count ) {
			$type                       = get_post_type_object( $post_type );
			$out['types'][ $post_type ] = array(
				'label' => $type ? (string) $type->labels->name : $post_type,
				'total' => $count['total'],
				'done'  => $count['done'],
			);
			$out['total']              += $count['total'];
			$out['done']               += $count['done'];
		}
		return $out;
	}

	/**
	 * Published default-language content with no version in $lang, pages first.
	 *
	 * @return WP_Post[]
	 */
	public function missing_posts( string $lang, int $limit = self::LIMIT ): array {
		$settings = $this->settings->get();
		$ids      = $this->translations->missing_ids( $settings->post_types(), $settings->default_code(), $lang, $limit );
		if ( ! $ids ) {
			return array();
		}
		_prime_post_caches( $ids, false, false );
		return array_values( array_filter( array_map( 'get_post', $ids ) ) );
	}

	/**
	 * Header/footer parts the theme uses and whether $lang has its copy.
	 *
	 * @return array<int, array{slug: string, title: string, exists: bool}>
	 */
	public function parts_status( string $lang ): array {
		if ( ! wp_is_block_theme() ) {
			return array();
		}
		$out = array();
		foreach ( $this->parts->used_parts() as $part ) {
			$out[] = array(
				'slug'   => $part->slug,
				'title'  => (string) $part->title,
				'exists' => $this->parts->exists( TemplateParts::slug_for( $part->slug, $lang ) ),
			);
		}
		return $out;
	}
}