<?php

namespace App\Services;

use App\Services\Cache\CacheServiceInterface;
use App\Support\Cache\CacheKey;

/**
 * Example service demonstrating the CacheService + CacheKey pattern.
 *
 * Cache key format: module:type[:param:value...]
 *
 * Examples produced:
 *   students:list:page:1
 *   students:list:page:2:status:active
 *   students:detail:id:15
 */
class StudentService
{
    private const MODULE = 'students';

    public function __construct(
        private readonly CacheServiceInterface $cache,
    ) {}

    public function getList(int $page = 1, ?string $status = null): array
    {
        $params = ['page' => $page];

        if ($status !== null) {
            $params['status'] = $status;
        }

        $key = CacheKey::build(self::MODULE, 'list', $params);

        return $this->cache->remember(
            key: $key,
            callback: fn () => $this->fetchList($page, $status),
            ttl: CacheServiceInterface::TTL_MEDIUM,
            tags: [self::MODULE],
        );
    }

    public function getDetail(int $id): array
    {
        $key = CacheKey::build(self::MODULE, 'detail', ['id' => $id]);

        return $this->cache->remember(
            key: $key,
            callback: fn () => $this->fetchDetail($id),
            ttl: CacheServiceInterface::TTL_LONG,
            tags: [self::MODULE],
        );
    }

    public function update(int $id, array $_data): void
    {
        // ... update DB logic ...

        // Forget only the stale detail entry
        $this->cache->forget(
            CacheKey::build(self::MODULE, 'detail', ['id' => $id])
        );

        // Also bust all list caches for this module
        $this->cache->clearByModule(self::MODULE);
    }

    public function getByIds(array $ids): array
    {
        // Array params are joined with "," — key: students:bulk:ids:1,2,3
        $key = CacheKey::build(self::MODULE, 'bulk', ['ids' => $ids]);

        return $this->cache->remember(
            key: $key,
            callback: fn () => $this->fetchByIds($ids),
            ttl: CacheServiceInterface::TTL_SHORT,
            tags: [self::MODULE],
        );
    }

    // -------------------------------------------------------------------------
    // Private DB fetch methods (replace with real Eloquent/Repository calls)
    // -------------------------------------------------------------------------

    private function fetchList(int $_page, ?string $_status): array
    {
        return []; // replace with Eloquent/Repository query
    }

    private function fetchDetail(int $_id): array
    {
        return []; // replace with Eloquent/Repository query
    }

    private function fetchByIds(array $_ids): array
    {
        return []; // replace with Eloquent/Repository query
    }
}