#!/usr/bin/env python3
"""Generate markdown summary from Loki logs."""
import datetime as dt
import os
from pathlib import Path
from typing import Any, Dict

import requests

LOKI_URL = os.getenv("LOKI_URL", "http://localhost:3100")
OUTPUT_DIR = Path(os.getenv("LAB_NOTES_DIR", "lab-notes"))
DEFAULT_QUERY = os.getenv("LOKI_QUERY", '{job="docker"}')


def query_loki(query: str, start: dt.datetime, end: dt.datetime) -> Dict[str, Any]:
    params = {
        "query": query,
        "start": int(start.timestamp() * 1_000_000_000),
        "end": int(end.timestamp() * 1_000_000_000),
        "limit": int(os.getenv("LOKI_LIMIT", "5000")),
    }
    resp = requests.get(
        f"{LOKI_URL.rstrip('/')}/loki/api/v1/query_range",
        params=params,
        timeout=30,
    )
    resp.raise_for_status()
    return resp.json()


def main() -> None:
    today = dt.datetime.utcnow().date()
    start = dt.datetime.combine(today, dt.time.min)
    end = dt.datetime.combine(today, dt.time.max)
    OUTPUT_DIR.mkdir(parents=True, exist_ok=True)

    md_path = OUTPUT_DIR / f"log_summary_{today.isoformat()}.md"
    data = query_loki(DEFAULT_QUERY, start, end)

    total_entries = 0
    streams = data.get("data", {}).get("result", [])
    for stream in streams:
        total_entries += len(stream.get("values", []))

    top_lines = min(5, len(streams))
    highlights = []
    for stream in streams[:top_lines]:
        job = stream.get("stream", {}).get("job", "unknown")
        highlights.append(f"- `{job}` → {len(stream.get('values', []))} entries")

    with md_path.open("w", encoding="utf-8") as f:
        f.write(f"# Log Summary — {today.isoformat()}\n\n")
        f.write(f"- Time window: {start.isoformat()} — {end.isoformat()} UTC\n")
        f.write(f"- Loki query: `{DEFAULT_QUERY}`\n")
        f.write(f"- Total entries (approx): **{total_entries}**\n\n")
        if highlights:
            f.write("## Top Streams\n")
            f.write("\n".join(highlights))
            f.write("\n")

    print(f"Written summary to {md_path}")


if __name__ == "__main__":
    main()