Initial commit

2026-03-12 12:43:56 +01:00
commit f733dee856
137 changed files with 51192 additions and 0 deletions
--- a/api/includes/CnbRates.php
+++ b/api/includes/CnbRates.php
@@ -0,0 +1,205 @@
+<?php
+
+/**
+ * Devizove kurzy CNB s file cache per datum.
+ *
+ * Pouziti:
+ *   $cnb = CnbRates::getInstance();
+ *   $czk = $cnb->toCzk(1000.0, 'EUR', '2026-03-01');
+ */
+
+declare(strict_types=1);
+
+class CnbRates
+{
+    private const API_URL = 'https://api.cnb.cz/cnbapi/exrates/daily';
+    private const CACHE_FILE = 'cnb_rates_cache.json';
+
+    // Kurzy starsi nez dnesek se nemeni, cachujem navzdy.
+    // Dnesni kurz cachujeme na 6 hodin (muze se behem dne aktualizovat).
+    private const TODAY_CACHE_TTL = 21600;
+
+    /**
+     * In-memory cache: date => currency => {rate, amount}
+     * @var array<string, array<string, array{rate: float, amount: int}>>
+     */
+    private array $ratesByDate = [];
+
+    private static ?CnbRates $instance = null;
+
+    public static function getInstance(): self
+    {
+        if (self::$instance === null) {
+            self::$instance = new self();
+        }
+        return self::$instance;
+    }
+
+    private function __construct()
+    {
+        $this->loadCache();
+    }
+
+    /**
+     * Prevede castku na CZK dle kurzu platneho k danemu datu.
+     */
+    public function toCzk(float $amount, string $currency, string $date = ''): float
+    {
+        if ($currency === 'CZK') {
+            return $amount;
+        }
+
+        $rates = $this->getRatesForDate($date ?: date('Y-m-d'));
+        if (!isset($rates[$currency])) {
+            return $amount;
+        }
+
+        $info = $rates[$currency];
+        return $amount * ($info['rate'] / $info['amount']);
+    }
+
+    /**
+     * Secte pole [{amount, currency, date?}] do jedne CZK castky.
+     * Kazda polozka muze mit vlastni datum pro kurz.
+     *
+     * @param array<int, array{amount: float, currency: string, date?: string}> $items
+     */
+    public function sumToCzk(array $items): float
+    {
+        $total = 0.0;
+        foreach ($items as $item) {
+            $total += $this->toCzk(
+                (float) $item['amount'],
+                (string) $item['currency'],
+                (string) ($item['date'] ?? '')
+            );
+        }
+        return round($total, 2);
+    }
+
+    /**
+     * @return array<string, array{rate: float, amount: int}>
+     */
+    private function getRatesForDate(string $date): array
+    {
+        if (isset($this->ratesByDate[$date])) {
+            return $this->ratesByDate[$date];
+        }
+
+        $rates = $this->fetchFromApi($date);
+        if ($rates !== []) {
+            $this->ratesByDate[$date] = $rates;
+            $this->saveCache();
+        }
+
+        return $rates;
+    }
+
+    // --- Cache ---
+
+    private function getCachePath(): string
+    {
+        return sys_get_temp_dir() . DIRECTORY_SEPARATOR . self::CACHE_FILE;
+    }
+
+    private function loadCache(): void
+    {
+        $path = $this->getCachePath();
+        if (!file_exists($path)) {
+            return;
+        }
+
+        $content = file_get_contents($path);
+        if ($content === false) {
+            return;
+        }
+
+        $data = json_decode($content, true);
+        if (!is_array($data)) {
+            return;
+        }
+
+        $today = date('Y-m-d');
+        foreach ($data as $date => $entry) {
+            if (!is_array($entry) || !isset($entry['rates'], $entry['fetched_at'])) {
+                continue;
+            }
+            // Dnesni kurz expiruje po TTL, starsi zustavaji navzdy
+            if ($date === $today) {
+                $age = time() - (int) $entry['fetched_at'];
+                if ($age > self::TODAY_CACHE_TTL) {
+                    continue;
+                }
+            }
+            $this->ratesByDate[$date] = $entry['rates'];
+        }
+    }
+
+    private function saveCache(): void
+    {
+        $path = $this->getCachePath();
+
+        // Nacist existujici cache a mergovat
+        $existing = [];
+        if (file_exists($path)) {
+            $content = file_get_contents($path);
+            if ($content !== false) {
+                $decoded = json_decode($content, true);
+                if (is_array($decoded)) {
+                    $existing = $decoded;
+                }
+            }
+        }
+
+        $now = time();
+        foreach ($this->ratesByDate as $date => $rates) {
+            // Neprepisuj existujici pokud uz tam je (zachovej fetched_at)
+            if (!isset($existing[$date])) {
+                $existing[$date] = [
+                    'rates' => $rates,
+                    'fetched_at' => $now,
+                ];
+            }
+        }
+
+        $json = json_encode($existing, JSON_THROW_ON_ERROR);
+        file_put_contents($path, $json, LOCK_EX);
+    }
+
+    // --- API ---
+
+    /**
+     * @return array<string, array{rate: float, amount: int}>
+     */
+    private function fetchFromApi(string $date): array
+    {
+        $url = self::API_URL . '?lang=EN&date=' . urlencode($date);
+
+        $context = stream_context_create([
+            'http' => ['timeout' => 5],
+        ]);
+
+        $response = @file_get_contents($url, false, $context);
+        if ($response === false) {
+            return [];
+        }
+
+        $data = json_decode($response, true);
+        if (!is_array($data) || !isset($data['rates'])) {
+            return [];
+        }
+
+        $rates = [];
+        foreach ($data['rates'] as $entry) {
+            if (!isset($entry['currencyCode'], $entry['rate'], $entry['amount'])) {
+                continue;
+            }
+            $rates[$entry['currencyCode']] = [
+                'rate' => (float) $entry['rate'],
+                'amount' => (int) $entry['amount'],
+            ];
+        }
+
+        return $rates;
+    }
+}