<?php

namespace App\Services;

use App\Models\Event;
use App\Models\EventMedia;
use App\Models\User;
use Illuminate\Support\Facades\Log;
use Illuminate\Support\Facades\Storage;

/**
 * Removes media files for every deletion path.
 *
 * Database rows disappear on their own through `cascadeOnDelete`, but the
 * files behind them do not. Paths are therefore collected *before* the rows
 * are deleted, and each deletion path routes through this service.
 */
class MediaCleaner
{
    /**
     * Delete the files of an event's media. The rows are left to the
     * caller / database cascade.
     */
    public function purgeEventMedia(Event $event): void
    {
        $this->deleteFiles($event->media()->get());
    }

    /**
     * Delete the files of every media row belonging to a user, plus the
     * user's settings background.
     */
    public function purgeUserMedia(User $user): void
    {
        $this->deleteFiles(EventMedia::query()->where('user_id', $user->id)->get());

        $this->delete('local', ["settings-media/{$user->id}/background.jpg"]);
    }

    /**
     * Delete the files of a single media row.
     */
    public function purgeMedia(EventMedia $media): void
    {
        $this->deleteFiles([$media]);
    }

    /**
     * @param  iterable<int, EventMedia>  $mediaItems
     */
    private function deleteFiles(iterable $mediaItems): void
    {
        $pathsByDisk = [];

        foreach ($mediaItems as $media) {
            $disk = $media->disk ?: 'local';

            foreach ([$media->path, $media->preview_path, $media->thumbnail_path] as $path) {
                if (is_string($path) && $path !== '') {
                    $pathsByDisk[$disk][] = $path;
                }
            }
        }

        foreach ($pathsByDisk as $disk => $paths) {
            $this->delete($disk, $paths);
        }
    }

    /**
     * @param  array<int, string>  $paths
     */
    private function delete(string $disk, array $paths): void
    {
        if ($paths === []) {
            return;
        }

        try {
            Storage::disk($disk)->delete($paths);
        } catch (\Throwable $e) {
            // A failed file delete must not abort the surrounding deletion —
            // an orphaned file is recoverable, a half-deleted account is not.
            Log::warning('Media cleanup failed', [
                'disk' => $disk,
                'paths' => $paths,
                'exception' => $e->getMessage(),
            ]);
        }
    }
}