<?php

declare(strict_types=1);

use App\Repository\ProductRepository;
use Psr\Http\Message\ResponseInterface as Response;
use Psr\Http\Message\ServerRequestInterface as Request;
use Slim\App;

return function (App $app): void {
    $container = $app->getContainer();

    if ($container === null) {
        throw new RuntimeException('DI container is not configured');
    }

    $json = static function (Response $response, mixed $data, int $status = 200): Response {
        $response->getBody()->write(json_encode($data, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES));

        return $response
            ->withHeader('Content-Type', 'application/json')
            ->withStatus($status);
    };

    $requiredFields = ['title', 'sku', 'stock', 'price', 'description', 'tagline'];

    $validate = static function (array $data) use ($requiredFields): ?string {
        foreach ($requiredFields as $field) {
            if (!isset($data[$field]) || $data[$field] === '') {
                return "Missing field: {$field}";
            }
        }

        return null;
    };

    $app->get('/', function (Request $request, Response $response) use ($json): Response {

        return $json($response, [
            'name' => 'Nerdshop API',
            'endpoints' => [
                'GET /products',
                'GET /products/{id}',
                'POST /products',
                'PUT /products/{id}',
                'PATCH /products/{id}',
                'DELETE /products/{id}',
            ],
        ]);
    });

    // app.get('/products', (req,res) => {
    //  const products =  productManager.getAll();
    //  res.send(products);
    // })

    $app->get('/products', function (Request $request, Response $response) use ($container, $json): Response {
        $repo = $container->get(ProductRepository::class);
        $items = array_map(static fn($product) => $product->toArray(), $repo->findAll());

        return $json($response, $items);
    });

    $app->get('/products/{id}', function (Request $request, Response $response, array $args) use ($container, $json): Response {
        $product = $container->get(ProductRepository::class)->findById($args['id']);

        if ($product === null) {
            return $json($response, ['error' => 'Product not found'], 404);
        }

        return $json($response, $product->toArray());
    });

    $app->post('/products', function (Request $request, Response $response) use ($container, $json, $validate): Response {
        $data = (array) $request->getParsedBody();
        $error = $validate($data);

        if ($error !== null) {
            return $json($response, ['error' => $error], 400);
        }

        try {
            $product = $container->get(ProductRepository::class)->create($data);
        } catch (\PDOException $exception) {
            if ((int) $exception->getCode() === 23000) {
                return $json($response, ['error' => 'SKU already exists'], 409);
            }

            throw $exception;
        }

        return $json($response, $product->toArray(), 201);
    });

    $app->put('/products/{id}', function (Request $request, Response $response, array $args) use ($container, $json, $validate): Response {
        $data = (array) $request->getParsedBody();
        $error = $validate($data);

        if ($error !== null) {
            return $json($response, ['error' => $error], 400);
        }

        try {
            $product = $container->get(ProductRepository::class)->update($args['id'], $data);
        } catch (\PDOException $exception) {
            if ((int) $exception->getCode() === 23000) {
                return $json($response, ['error' => 'SKU already exists'], 409);
            }

            throw $exception;
        }

        if ($product === null) {
            return $json($response, ['error' => 'Product not found'], 404);
        }

        return $json($response, $product->toArray());
    });

    $app->patch('/products/{id}', function (Request $request, Response $response, array $args) use ($container, $json): Response {
        $data = (array) $request->getParsedBody();
        $allowed = ['title', 'sku', 'stock', 'price', 'description', 'tagline'];
        $patch = array_intersect_key($data, array_flip($allowed));

        if ($patch === []) {
            return $json($response, ['error' => 'No fields to update'], 400);
        }

        try {
            $product = $container->get(ProductRepository::class)->patch($args['id'], $patch);
        } catch (\PDOException $exception) {
            if ((int) $exception->getCode() === 23000) {
                return $json($response, ['error' => 'SKU already exists'], 409);
            }

            throw $exception;
        }

        if ($product === null) {
            return $json($response, ['error' => 'Product not found'], 404);
        }

        return $json($response, $product->toArray());
    });

    $app->delete('/products/{id}', function (Request $request, Response $response, array $args) use ($container, $json): Response {
        $deleted = $container->get(ProductRepository::class)->delete($args['id']);

        if (!$deleted) {
            return $json($response, ['error' => 'Product not found'], 404);
        }

        return $response->withStatus(204);
    });
};