feat: exchanger currency

.gitignore

@@ -1 +1,3 @@
 /vendor/
+
+.idea/

src/Controller/ExchangeController.php

@@ -0,0 +1,57 @@
+<?php
+declare(strict_types=1);
+
+namespace App\Controller;
+
+use App\Validation\ExchangeRequestValidator;
+use App\Service\ExchangeService;
+use App\Http\JsonResponse;
+use App\Utils\Url;
+
+class ExchangeController
+{
+    private ExchangeService $exchangeService;
+    private ExchangeRequestValidator $validator;
+    private Url $common;
+
+    public function __construct(
+        ExchangeService          $exchangeService,
+        ExchangeRequestValidator $validator,
+        Url                      $common
+    )
+    {
+        $this->exchangeService = $exchangeService;
+        $this->validator = $validator;
+        $this->common = $common;
+    }
+
+    public function handle(string $requestUri): void
+    {
+        $segments = $this->common->getExtractSegments($requestUri);
+
+        $validation = $this->validator->validate($segments);
+
+        if ($validation['valid'] !== true) {
+            JsonResponse::send(['error' => $validation['message']], 400);
+            return;
+        }
+
+        [$amount, $from, $to, $rate] = $validation['segments'];
+
+        $result = $this->exchangeService->convert(
+            (float)$amount,
+            $from,
+            $to,
+            (float)$rate
+        );
+
+        if ($result === null) {
+            JsonResponse::send(['error' => 'Unsupported currency conversion.'], 400);
+            return;
+        }
+
+        JsonResponse::send($result, 200);
+    }
+
+
+}

src/Domain/Currency.php

@@ -0,0 +1,36 @@
+<?php
+declare(strict_types=1);
+
+namespace App\Domain;
+
+class Currency
+{
+    public const string BRL = 'BRL';
+    public const string USD = 'USD';
+    public const string EUR = 'EUR';
+
+    private const array SYMBOLS = [
+        self::BRL => 'R$',
+        self::USD => '$',
+        self::EUR => '€',
+    ];
+
+    public static function isSupported(string $currency): bool
+    {
+        return in_array($currency, self::supported(), true);
+    }
+
+    public static function supported(): array
+    {
+        return [
+            self::BRL,
+            self::USD,
+            self::EUR,
+        ];
+    }
+
+    public static function getSymbol(string $currency): string
+    {
+        return self::SYMBOLS[$currency] ?? '';
+    }
+}

src/Http/JsonResponse.php

@@ -0,0 +1,15 @@
+<?php
+declare(strict_types=1);
+
+namespace App\Http;
+
+class JsonResponse
+{
+    public static function send(array $data, int $statusCode): void
+    {
+        http_response_code($statusCode);
+        header('Content-Type: application/json; charset=utf-8');
+
+        echo json_encode($data, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
+    }
+}

src/Service/ExchangeService.php

@@ -0,0 +1,32 @@
+<?php
+declare(strict_types=1);
+namespace App\Service;
+
+use App\Domain\Currency;
+
+class ExchangeService
+{
+    public function convert(float $amount, string $from, string $to, float $rate): ?array
+    {
+        if (!$this->isSupportedConversion($from, $to)) {
+            return null;
+        }
+
+        return [
+            'valorConvertido' => $amount * $rate,
+            'simboloMoeda' => Currency::getSymbol($to),
+        ];
+    }
+
+    private function isSupportedConversion(string $from, string $to): bool
+    {
+        $supportedConversions = [
+            Currency::BRL . '-' . Currency::USD,
+            Currency::USD . '-' . Currency::BRL,
+            Currency::BRL . '-' . Currency::EUR,
+            Currency::EUR . '-' . Currency::BRL,
+        ];
+
+        return in_array($from . '-' . $to, $supportedConversions, true);
+    }
+}

src/Utils/Url.php

@@ -0,0 +1,69 @@
+<?php
+declare(strict_types=1);
+
+namespace App\Utils;
+class Url
+{
+    private function extractSegments(string $requestUri): array
+    {
+        $path = (string)parse_url($requestUri, PHP_URL_PATH);
+        $query = (string)parse_url($requestUri, PHP_URL_QUERY);
+
+        $candidates = [];
+
+        if ($path !== '') {
+            $candidates[] = $path;
+        }
+
+        if ($query !== '') {
+            parse_str($query, $queryParams);
+
+            foreach (['request', 'route', 'path', 'q'] as $key) {
+                if (!empty($queryParams[$key]) && is_string($queryParams[$key])) {
+                    $candidates[] = $queryParams[$key];
+                }
+            }
+
+            if (str_contains($query, '/')) {
+                $candidates[] = $query;
+            }
+        }
+
+        foreach ($candidates as $candidate) {
+            $segments = $this->normalizeSegments($candidate);
+
+            if (count($segments) >= 4) {
+                return array_slice($segments, -4);
+            }
+
+            if ($segments !== []) {
+                return $segments;
+            }
+        }
+
+        return [];
+    }
+
+    private function normalizeSegments(string $value): array
+    {
+        $value = str_replace('index.php', '', $value);
+        $value = trim($value, " \t\n\r\0\x0B/");
+
+        if ($value === '') {
+            return [];
+        }
+
+        return array_values(array_filter(
+            explode('/', $value),
+            static function (string $segment): bool {
+                return trim($segment) !== '';
+            }
+        ));
+    }
+
+    public function getExtractSegments(string $requestUri): array
+    {
+        return $this->extractSegments($requestUri);
+
+    }
+}

src/Validation/ExchangeRequestValidator.php

@@ -0,0 +1,92 @@
+<?php
+declare(strict_types=1);
+
+namespace App\Validation;
+
+use App\Domain\Currency;
+
+class ExchangeRequestValidator
+{
+    public function  validate(array $segments): array
+    {
+        $segments = array_values(
+            array_filter(
+                array_map(
+                    static function ($segment): string {
+                        return trim((string) $segment);
+                    },
+                    $segments
+                ),
+                static function (string $segment): bool {
+                    return $segment !== '';
+                }
+            )
+        );
+
+        if (count($segments) !== 4) {
+            return [
+                'valid' => false,
+                'message' => 'Invalid route parameters.',
+                'debug' => $segments,
+                'count' => count($segments),
+            ];
+        }
+
+        [$amount, $from, $to, $rate] = $segments;
+
+        if (!$this->isValidPositiveNumber($amount)) {
+            return [
+                'valid' => false,
+                'message' => 'Invalid amount.',
+                'debug' => $segments,
+            ];
+        }
+
+        if (!$this->isValidCurrency($from)) {
+            return [
+                'valid' => false,
+                'message' => 'Invalid source currency.',
+                'debug' => $segments,
+            ];
+        }
+
+        if (!$this->isValidCurrency($to)) {
+            return [
+                'valid' => false,
+                'message' => 'Invalid target currency.',
+                'debug' => $segments,
+            ];
+        }
+
+        if (!$this->isValidPositiveNumber($rate)) {
+            return [
+                'valid' => false,
+                'message' => 'Invalid rate.',
+                'debug' => $segments,
+            ];
+        }
+
+        return [
+            'valid' => true,
+            'segments' => $segments,
+        ];
+    }
+
+    private function isValidPositiveNumber(string $value): bool
+    {
+        if (!is_numeric($value)) {
+            return false;
+        }
+
+        return (float) $value > 0;
+    }
+
+    private function isValidCurrency(string $currency): bool
+    {
+        if (!preg_match('/^[A-Z]{3}$/', $currency)) {
+            return false;
+        }
+
+        return Currency::isSupported($currency);
+    }
+}

src/index.php

@@ -16,3 +16,15 @@
 
 require __DIR__ . '/../vendor/autoload.php';
 
+use App\Controller\ExchangeController;
+use App\Service\ExchangeService;
+use App\Validation\ExchangeRequestValidator;
+use App\Utils\Url;
+
+$controller = new ExchangeController(
+    new ExchangeService(),
+    new ExchangeRequestValidator(),
+    new Url()
+);
+
+$controller->handle($_SERVER['REQUEST_URI'] ?? '/');