<?php
namespace Relay\Files;

use Relay\Multisite\Scope;
use Relay\Multisite\SubsiteFiles;

/** What a site has in each file group: its top-level items, their names and which are active (spec §5.1). */
final class Inventory
{
    /**
     * $scope: a subsite's inventory — its uploads, and what is active for it (SubsiteFiles::active()).
     *
     * @return array{themes: array[], plugins: array[], mu-plugins: string[], uploads: string[], other: string[], wp: string}
     */
    public static function current(?Scope $scope = null): array
    {
        global $wp_version;
        $roots = Groups::roots($scope);
        $excludes = Groups::excludes($roots, [], $scope !== null ? SubsiteFiles::untouched($scope) : []);
        $out = [];
        foreach (['themes', 'plugins'] as $group) {
            $active = $scope !== null ? SubsiteFiles::active($scope, $group) : self::active($group);
            $out[$group] = [];
            foreach (self::top_level($roots[$group], $excludes[$group]) as $item) {
                $out[$group][] = ['name' => $item, 'title' => self::title($group, $roots[$group], $item), 'active' => in_array($item, $active, true)];
            }
        }
        foreach (['mu-plugins', 'uploads', 'other'] as $group) {
            $out[$group] = self::top_level($roots[$group], $excludes[$group]);
        }
        $out['wp'] = (string) $wp_version;
        return $out;
    }

    /**
     * themes: the current theme and its parent; plugins: the items holding active plugins. Read as this site stores
     * them, not through the option filters other plugins may add.
     *
     * @return string[]
     */
    public static function active(string $group): array
    {
        if ($group === 'themes') {
            return array_values(array_unique(array_filter([(string) get_option('stylesheet'), (string) get_option('template')])));
        }
        if ($group === 'plugins') {
            global $wpdb;
            $raw = $wpdb->get_var("SELECT option_value FROM {$wpdb->options} WHERE option_name = 'active_plugins'"); // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- the stored list itself: during a signed request Relay's mu-plugin filters active_plugins so only Relay loads
            $plugins = is_string($raw) ? maybe_unserialize($raw) : [];
            $items = [];
            foreach (is_array($plugins) ? $plugins : [] as $basename) {
                if (is_string($basename) && $basename !== '') {
                    $items[] = RelPath::top($basename);
                }
            }
            return array_values(array_unique($items));
        }
        return [];
    }

    /** @return string[] sorted names of the files and folders directly in $root that are not left out (no symlinks) */
    public static function top_level(string $root, Excludes $excludes): array
    {
        $names = [];
        foreach (is_dir($root) ? (scandir($root) ?: []) : [] as $name) {
            if ($name === '.' || $name === '..' || is_link($root . '/' . $name) || !RelPath::valid($name) || $excludes->excluded($name)) {
                continue;
            }
            $names[] = $name;
        }
        sort($names);
        return $names;
    }

    private static function title(string $group, string $root, string $item): string
    {
        if ($group === 'themes') {
            $theme = wp_get_theme($item, $root);
            return $theme->exists() ? (string) $theme->get('Name') : $item;
        }
        $files = is_dir($root . '/' . $item) ? (glob($root . '/' . $item . '/*.php') ?: []) : [$root . '/' . $item];
        foreach ($files as $file) {
            if (substr($file, -4) !== '.php' || !is_readable($file)) {
                continue;
            }
            $name = get_file_data($file, ['Name' => 'Plugin Name'])['Name'] ?? '';
            if ($name !== '') {
                return $name;
            }
        }
        return $item;
    }
}