<?php

declare(strict_types=1);

namespace BattleForge\Http\Handlers;

use BattleForge\Application\ScenarioSerializer;
use BattleForge\Domain\ScenarioValidator;
use BattleForge\Http\Request;
use BattleForge\Http\Response;
use InvalidArgumentException;

final class GetBundledScenario
{
    private const ID_PATTERN = '/^[a-z0-9-]+$/';

    public function __construct(private readonly string $scenariosDir)
    {
    }

    /** @param array<string, string> $params */
    public function handle(Request $request, array $params): Response
    {
        $id = (string) ($params['id'] ?? '');

        if (preg_match(self::ID_PATTERN, $id) !== 1) {
            return Response::json(404, ['error' => 'not found']);
        }

        $manifestPath = $this->scenariosDir . '/manifest.json';
        $manifest = [];
        if (is_file($manifestPath)) {
            $decoded = json_decode((string) file_get_contents($manifestPath), true);
            if (is_array($decoded)) {
                $manifest = $decoded;
            }
        }

        if (!isset($manifest[$id])) {
            return Response::json(404, ['error' => 'not found']);
        }

        $fixturePath = $this->scenariosDir . '/' . $id . '.json';
        $real = realpath($fixturePath);
        $realDir = realpath($this->scenariosDir);
        $insideBase = $real !== false
            && $realDir !== false
            && str_starts_with($real, $realDir . DIRECTORY_SEPARATOR);
        if ($insideBase === false || !is_file($real)) {
            return Response::json(404, ['error' => 'not found']);
        }

        $data = json_decode((string) file_get_contents($real), true, flags: JSON_THROW_ON_ERROR);
        if (!is_array($data)) {
            return Response::json(500, ['error' => 'fixture invalid', 'details' => ['Fixture JSON is not an object.']]);
        }

        try {
            $scenario = ScenarioSerializer::scenarioFromArray($data);
        } catch (InvalidArgumentException $exception) {
            return Response::json(500, ['error' => 'fixture invalid', 'details' => [$exception->getMessage()]]);
        }

        $errors = ScenarioValidator::validate($scenario);
        if ($errors !== []) {
            return Response::json(500, ['error' => 'fixture invalid', 'details' => $errors]);
        }

        return Response::json(200, ScenarioSerializer::scenarioToArray($scenario));
    }
}