From 8bd7948eacac204bf50818c252765c12c28e1643 Mon Sep 17 00:00:00 2001
From: Mika <kontakt@donau2space.de>
Date: Sun, 29 Mar 2026 03:07:26 +0000
Subject: [PATCH] Add logger/src/logger/core.py

---
 logger/src/logger/core.py | 106 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 106 insertions(+)
 create mode 100644 logger/src/logger/core.py

diff --git a/logger/src/logger/core.py b/logger/src/logger/core.py
new file mode 100644
index 0000000..1f60f27
--- /dev/null
+++ b/logger/src/logger/core.py
@@ -0,0 +1,106 @@
+import json
+import time
+from datetime import datetime
+from pathlib import Path
+from typing import Any, Dict, List
+
+
+class LogEntry:
+    """Repräsentiert einen einzelnen Messwert des Sensors und seine Metadaten."""
+
+    def __init__(
+        self,
+        timestamp: datetime,
+        led_id: str,
+        lumens: float,
+        peak_wavelength: float,
+        latitude: float,
+        longitude: float,
+    ) -> None:
+        if not isinstance(timestamp, datetime):
+            raise TypeError("timestamp must be a datetime instance")
+        if not isinstance(led_id, str):
+            raise TypeError("led_id must be a string")
+        for val, name in [
+            (lumens, "lumens"),
+            (peak_wavelength, "peak_wavelength"),
+            (latitude, "latitude"),
+            (longitude, "longitude"),
+        ]:
+            if not isinstance(val, (int, float)):
+                raise TypeError(f"{name} must be a numeric type")
+
+        self.timestamp = timestamp
+        self.led_id = led_id
+        self.lumens = float(lumens)
+        self.peak_wavelength = float(peak_wavelength)
+        self.latitude = float(latitude)
+        self.longitude = float(longitude)
+
+    def to_dict(self) -> Dict[str, Any]:
+        """Konvertiert den Log-Eintrag in ein Dictionary zur JSON-Serialisierung."""
+        return {
+            "timestamp": self.timestamp.isoformat(),
+            "led_id": self.led_id,
+            "lumens": self.lumens,
+            "peak_wavelength": self.peak_wavelength,
+            "latitude": self.latitude,
+            "longitude": self.longitude,
+        }
+
+
+def _simulate_sensor_reading() -> LogEntry:
+    """Erzeugt simulierte Sensordaten für Test- und Entwicklungszwecke."""
+    from random import uniform, choice
+
+    led_id = choice(["LED_A", "LED_B", "LED_C"])
+    lumens = round(uniform(100.0, 1000.0), 2)
+    peak_wavelength = round(uniform(400.0, 700.0), 1)
+    latitude = round(uniform(-90.0, 90.0), 6)
+    longitude = round(uniform(-180.0, 180.0), 6)
+    return LogEntry(
+        timestamp=datetime.utcnow(),
+        led_id=led_id,
+        lumens=lumens,
+        peak_wavelength=peak_wavelength,
+        latitude=latitude,
+        longitude=longitude,
+    )
+
+
+def start_logging(interval: float, duration: float) -> str:
+    """Startet die periodische Aufzeichnung von Sensordaten über einen gegebenen Zeitraum.
+
+    Args:
+        interval: Zeitintervall zwischen zwei Messungen in Sekunden.
+        duration: Gesamtzeit der Aufzeichnung in Sekunden.
+
+    Returns:
+        Pfad zur erzeugten JSON-Logdatei mit den aufgezeichneten Messungen.
+    """
+    if not isinstance(interval, (int, float)) or interval <= 0:
+        raise ValueError("interval must be a positive number")
+    if not isinstance(duration, (int, float)) or duration <= 0:
+        raise ValueError("duration must be a positive number")
+
+    output_dir = Path("output/logs")
+    output_dir.mkdir(parents=True, exist_ok=True)
+
+    timestamp_str = datetime.utcnow().strftime("%Y%m%d_%H%M%S")
+    log_path = output_dir / f"session_log_{timestamp_str}.json"
+
+    entries: List[Dict[str, Any]] = []
+
+    start_time = time.time()
+    while (time.time() - start_time) < duration:
+        entry = _simulate_sensor_reading()
+        entries.append(entry.to_dict())
+        time.sleep(interval)
+
+    with open(log_path, "w", encoding="utf-8") as f:
+        json.dump(entries, f, ensure_ascii=False, indent=2)
+
+    # Validation assertion for CI safety
+    assert log_path.exists(), "Log file should have been created."
+
+    return str(log_path)