Add AI summarization

summarizer.py

@@ -0,0 +1,84 @@
+"""
+OpenAI/OpenRouter summarizer utility.
+
+Uses OPENAI_API_KEY and OPENAI_URL from environment (via Config).
+"""
+
+from __future__ import annotations
+
+import json
+from typing import Dict, List
+
+import requests
+
+from config import Config
+
+
+class SummarizationError(RuntimeError):
+    """Raised when summarization fails."""
+
+
+def summarize_text(text: str, max_points: int = 3) -> Dict[str, List[str] | str]:
+    """
+    Summarize text into a short summary and key points.
+
+    Returns:
+        {
+            "summary": "string",
+            "key_points": ["point 1", "point 2", ...]
+        }
+    """
+    if not text or not text.strip():
+        return {"summary": "", "key_points": []}
+
+    if not Config.OPENAI_API_KEY:
+        raise SummarizationError("OPENAI_API_KEY is not set")
+
+    payload = {
+        "model": Config.OPENAI_MODEL,
+        "messages": [
+            {
+                "role": "system",
+                "content": (
+                    "You are a precise summarizer. Return JSON only with keys "
+                    "`summary` and `key_points` (array of strings). Do not add extra keys."
+                ),
+            },
+            {
+                "role": "user",
+                "content": (
+                    "Summarize the following content in 2-4 sentences and provide "
+                    f"{max_points} key points.\n\n"
+                    f"CONTENT:\n{text}"
+                ),
+            },
+        ],
+        "temperature": 0.2,
+        "max_tokens": 400,
+    }
+
+    headers = {
+        "Authorization": f"Bearer {Config.OPENAI_API_KEY}",
+        "Content-Type": "application/json",
+    }
+
+    try:
+        response = requests.post(
+            Config.OPENAI_URL,
+            headers=headers,
+            json=payload,
+            timeout=Config.OPENAI_TIMEOUT,
+        )
+        response.raise_for_status()
+        data = response.json()
+    except Exception as exc:
+        raise SummarizationError(f"Request failed: {exc}") from exc
+
+    try:
+        content = data["choices"][0]["message"]["content"].strip()
+        result = json.loads(content)
+        summary = result.get("summary", "").strip()
+        key_points = [p.strip() for p in result.get("key_points", []) if p.strip()]
+        return {"summary": summary, "key_points": key_points}
+    except Exception as exc:
+        raise SummarizationError(f"Invalid response format: {exc}") from exc