From d1e357fa3c7f18e4ad1bea0e54c5b0382b4f0ff7 Mon Sep 17 00:00:00 2001
From: Mika <kontakt@donau2space.de>
Date: Thu, 5 Mar 2026 15:48:01 +0000
Subject: [PATCH] Add data_analysis/src/data_analysis/core.py

---
 data_analysis/src/data_analysis/core.py | 71 +++++++++++++++++++++++++
 1 file changed, 71 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..3168693
--- /dev/null
+++ b/data_analysis/src/data_analysis/core.py
@@ -0,0 +1,71 @@
+from __future__ import annotations
+import logging
+from typing import List, Dict, Any
+import pandas as pd
+
+
+logging.basicConfig(level=logging.INFO)
+logger = logging.getLogger(__name__)
+
+
+class DataValidationError(Exception):
+    """Raised when input data validation fails."""
+    pass
+
+
+def _validate_input_data(data: List[Dict[str, Any]]) -> None:
+    """Validiert, ob die Eingabedaten die erforderlichen Felder enthalten."""
+    required_fields = {"context", "pinned_status", "delta_t", "warn"}
+    if not isinstance(data, list):
+        raise DataValidationError("Input data must be a list of dicts.")
+    for i, record in enumerate(data):
+        if not isinstance(record, dict):
+            raise DataValidationError(f"Each entry must be a dict (index {i}).")
+        if not required_fields.issubset(record.keys()):
+            missing = required_fields - record.keys()
+            raise DataValidationError(f"Missing fields {missing} in record at index {i}.")
+
+
+def analyze_data(data: List[Dict[str, Any]]) -> Dict[str, Any]:
+    """Analysiert Datensätze und identifiziert Δt<0-Fälle sowie berechnet Aggregationen.
+
+    Parameters
+    ----------
+    data : list[dict]
+        Liste von Datensätzen mit Feldern: context, pinned_status, delta_t, warn.
+
+    Returns
+    -------
+    dict
+        Analyseergebnis: near_expiry_count, fresh_count, warn_rate.
+    """
+    logger.debug("Starting analyze_data with %d records", len(data))
+
+    _validate_input_data(data)
+
+    df = pd.DataFrame(data)
+    required_columns = ["context", "pinned_status", "delta_t", "warn"]
+    if not all(col in df.columns for col in required_columns):
+        raise DataValidationError("Input data missing required columns.")
+
+    # Filter nur auf unpinned und negative delta_t-Fälle
+    unpinned_df = df[(df["pinned_status"] == "unpinned") & (df["delta_t"] < 0)]
+    logger.debug("Filtered unpinned negative delta_t count: %d", len(unpinned_df))
+
+    near_expiry_count = int((unpinned_df["context"] == "near_expiry").sum())
+    fresh_count = int((unpinned_df["context"] == "fresh").sum())
+
+    warn_total = int(unpinned_df["warn"].sum())
+    warn_rate = float(warn_total / len(unpinned_df)) if len(unpinned_df) > 0 else 0.0
+
+    result = {
+        "near_expiry_count": near_expiry_count,
+        "fresh_count": fresh_count,
+        "warn_rate": round(warn_rate, 4),
+    }
+
+    logger.info("Analysis complete: %s", result)
+    assert all(key in result for key in ["near_expiry_count", "fresh_count", "warn_rate"]), (
+        "Result missing expected keys!"
+    )
+    return result