From b8c072029151f09c08142f84434e6e2986017961 Mon Sep 17 00:00:00 2001
From: Mika <kontakt@donau2space.de>
Date: Sun, 5 Jul 2026 02:07:35 +0000
Subject: [PATCH] Add data_analysis/src/data_analysis/core.py

---
 data_analysis/src/data_analysis/core.py | 105 ++++++++++++++++++++++++
 1 file changed, 105 insertions(+)
 create mode 100644 data_analysis/src/data_analysis/core.py

diff --git a/data_analysis/src/data_analysis/core.py b/data_analysis/src/data_analysis/core.py
new file mode 100644
index 0000000..f59d884
--- /dev/null
+++ b/data_analysis/src/data_analysis/core.py
@@ -0,0 +1,105 @@
+from __future__ import annotations
+import logging
+from dataclasses import dataclass
+from datetime import datetime
+from pathlib import Path
+from typing import Optional
+import pandas as pd
+import matplotlib.pyplot as plt
+
+
+# Logging setup for CI readiness
+logger = logging.getLogger(__name__)
+if not logger.handlers:
+    handler = logging.StreamHandler()
+    formatter = logging.Formatter('%(asctime)s - %(levelname)s - %(message)s')
+    handler.setFormatter(formatter)
+    logger.addHandler(handler)
+logger.setLevel(logging.INFO)
+
+
+@dataclass
+class MeasurementRecord:
+    timestamp: datetime
+    temperature: float
+    humidity: float
+    lux: float
+
+    @staticmethod
+    def validate_row(row: pd.Series) -> bool:
+        try:
+            datetime.fromisoformat(str(row['timestamp']))
+            float(row['temperature'])
+            float(row['humidity'])
+            float(row['lux'])
+        except (ValueError, TypeError, KeyError):
+            return False
+        return True
+
+
+def load_data(filename: str) -> pd.DataFrame:
+    """Lädt und bereinigt CSV-Daten mit Zeit, Temperatur, Feuchtigkeit, Licht."""
+    assert isinstance(filename, str), "filename muss ein String sein"
+
+    path = Path(filename)
+    if not path.exists():
+        raise FileNotFoundError(f"Datei nicht gefunden: {filename}")
+
+    logger.info("Lade CSV-Daten aus %s", filename)
+    df = pd.read_csv(path)
+
+    required_columns = {'timestamp', 'temperature', 'humidity', 'lux'}
+    if not required_columns.issubset(df.columns):
+        raise ValueError(f"CSV muss Spalten {required_columns} enthalten")
+
+    # Typkonvertierung und Validierung
+    df['timestamp'] = pd.to_datetime(df['timestamp'], errors='coerce')
+    df['temperature'] = pd.to_numeric(df['temperature'], errors='coerce')
+    df['humidity'] = pd.to_numeric(df['humidity'], errors='coerce')
+    df['lux'] = pd.to_numeric(df['lux'], errors='coerce')
+
+    # Drop unvollständige Zeilen
+    before_drop = len(df)
+    df.dropna(subset=['timestamp', 'temperature', 'humidity', 'lux'], inplace=True)
+    after_drop = len(df)
+
+    logger.info("Bereinigte Daten: %d Zeilen entfernt (%d -> %d)", before_drop - after_drop, before_drop, after_drop)
+
+    return df
+
+
+def plot_data(data: pd.DataFrame, output_path: Optional[str] = None) -> None:
+    """Erstellt Plots für Temperatur, Luftfeuchtigkeit und Lichtintensität."""
+    if not isinstance(data, pd.DataFrame):
+        raise TypeError("data muss ein pandas.DataFrame sein")
+
+    required_columns = {'timestamp', 'temperature', 'humidity', 'lux'}
+    if not required_columns.issubset(data.columns):
+        raise ValueError(f"DataFrame muss Spalten {required_columns} enthalten")
+
+    if data.empty:
+        raise ValueError("DataFrame ist leer, kein Plot möglich")
+
+    fig, ax1 = plt.subplots(figsize=(10, 6))
+    ax1.plot(data['timestamp'], data['temperature'], color='tab:red', label='Temperatur (°C)')
+    ax1.set_xlabel('Zeit')
+    ax1.set_ylabel('Temperatur (°C)', color='tab:red')
+    ax1.tick_params(axis='y', labelcolor='tab:red')
+
+    ax2 = ax1.twinx()
+    ax2.plot(data['timestamp'], data['lux'], color='tab:blue', alpha=0.6, label='Licht (Lux)')
+    ax2.set_ylabel('Licht (Lux)', color='tab:blue')
+    ax2.tick_params(axis='y', labelcolor='tab:blue')
+
+    plt.title('Zeitverlauf: Temperatur und Licht')
+    fig.autofmt_xdate()
+    fig.tight_layout()
+
+    if output_path:
+        Path(output_path).parent.mkdir(parents=True, exist_ok=True)
+        plt.savefig(output_path, dpi=150)
+        logger.info("Plot gespeichert in %s", output_path)
+    else:
+        plt.show()
+
+    plt.close(fig)