feat: ForecastMapper and file Cache

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>

tests/CacheTest.php

@@ -0,0 +1,72 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Weerscherm\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Weerscherm\Cache;
+
+final class CacheTest extends TestCase
+{
+    private string $dir;
+
+    protected function setUp(): void
+    {
+        $this->dir = sys_get_temp_dir() . '/weerscherm-cache-' . uniqid();
+    }
+
+    protected function tearDown(): void
+    {
+        array_map('unlink', glob($this->dir . '/*') ?: []);
+        @rmdir($this->dir);
+    }
+
+    public function testWriteThenReadRoundTrip(): void
+    {
+        $cache = new Cache($this->dir);
+        $cache->write('stations', ['a' => 1.5, 'b' => null], 1000);
+
+        self::assertSame(['data' => ['a' => 1.5, 'b' => null], 'stored_at' => 1000], $cache->read('stations'));
+    }
+
+    public function testMissingKeyReadsNull(): void
+    {
+        self::assertNull((new Cache($this->dir))->read('nope'));
+    }
+
+    public function testCorruptFileReadsNull(): void
+    {
+        mkdir($this->dir, 0700, true);
+        file_put_contents($this->dir . '/broken.json', '{not json');
+
+        self::assertNull((new Cache($this->dir))->read('broken'));
+    }
+
+    public function testFreshness(): void
+    {
+        $cache = new Cache($this->dir);
+        $cache->write('k', [], 1000);
+
+        self::assertTrue($cache->isFresh('k', 300, 1299));
+        self::assertFalse($cache->isFresh('k', 300, 1300));
+        self::assertFalse($cache->isFresh('missing', 300, 1000));
+    }
+
+    public function testKeyIsSanitised(): void
+    {
+        $cache = new Cache($this->dir);
+        $cache->write('../Evil Key', ['x' => 1], 1);
+
+        self::assertFileExists($this->dir . '/evil_key.json');
+        self::assertSame(['x' => 1], $cache->read('../Evil Key')['data']);
+    }
+
+    public function testWriteCreatesDirectory(): void
+    {
+        (new Cache($this->dir . '/nested'))->write('k', [], 1);
+        self::assertDirectoryExists($this->dir . '/nested');
+        unlink($this->dir . '/nested/k.json');
+        rmdir($this->dir . '/nested');
+    }
+}

tests/ForecastMapperTest.php

@@ -0,0 +1,57 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Weerscherm\Tests;
+
+use PHPUnit\Framework\TestCase;
+use Weerscherm\ForecastMapper;
+
+final class ForecastMapperTest extends TestCase
+{
+    /** @return array<string, mixed> */
+    private function daily(): array
+    {
+        return json_decode((string) file_get_contents(__DIR__ . '/fixtures/forecast.json'), true)['daily'];
+    }
+
+    public function testSkipsTodayAndReturnsFiveDays(): void
+    {
+        $f = ForecastMapper::map($this->daily());
+
+        self::assertCount(5, $f);
+        self::assertSame([
+            'date' => '2026-09-12', 'weather_code' => 2, 'temp_max' => 18.3, 'temp_min' => 10.1,
+            'precip_mm' => 0.4, 'precip_prob' => 20,
+        ], $f[0]);
+        self::assertSame('2026-09-16', $f[4]['date']);
+    }
+
+    public function testNullValuesStayNull(): void
+    {
+        $daily = $this->daily();
+        $daily['weather_code'][3] = null;
+        $daily['precipitation_probability_max'][3] = null;
+
+        $f = ForecastMapper::map($daily);
+
+        self::assertNull($f[2]['weather_code']);
+        self::assertNull($f[2]['precip_prob']);
+        self::assertSame(17.4, $f[2]['temp_max']);
+    }
+
+    public function testShorterResponseGivesFewerDays(): void
+    {
+        $daily = $this->daily();
+        foreach ($daily as $key => $values) {
+            $daily[$key] = array_slice($values, 0, 3);
+        }
+
+        self::assertCount(2, ForecastMapper::map($daily));
+    }
+
+    public function testMissingTimeArrayGivesEmptyList(): void
+    {
+        self::assertSame([], ForecastMapper::map([]));
+    }
+}

tests/fixtures/forecast.json

@@ -0,0 +1,25 @@
+{
+  "latitude": 51.82,
+  "longitude": 6.56,
+  "generationtime_ms": 0.2,
+  "utc_offset_seconds": 7200,
+  "timezone": "Europe/Berlin",
+  "timezone_abbreviation": "CEST",
+  "elevation": 20.0,
+  "daily_units": {
+    "time": "iso8601",
+    "weather_code": "wmo code",
+    "temperature_2m_max": "°C",
+    "temperature_2m_min": "°C",
+    "precipitation_sum": "mm",
+    "precipitation_probability_max": "%"
+  },
+  "daily": {
+    "time": ["2026-09-11", "2026-09-12", "2026-09-13", "2026-09-14", "2026-09-15", "2026-09-16"],
+    "weather_code": [3, 2, 0, 61, 80, 2],
+    "temperature_2m_max": [17.9, 18.3, 20.1, 17.4, 15.2, 16.0],
+    "temperature_2m_min": [11.0, 10.1, 11.3, 12.0, 9.4, 8.1],
+    "precipitation_sum": [0.0, 0.4, 0.0, 8.2, 3.1, 0.2],
+    "precipitation_probability_max": [10, 20, 5, 80, 60, 15]
+  }
+}