"""Drain the digest enrichment queue (X12) — local LLM enrichment of pending digests.

The web/n8n upload path creates digest rows with extraction_status='pending'
(container-safe: stage + extract_text only). The LLM metadata extraction +
embedding + autolink MUST run locally (claude_session is local-only — the
``claude`` CLI is not in the container). This script is that local drainer:

  pending digests → digest_library.enrich_digest (Sonnet, tools="") → completed

Concurrency-limited (avoids LLM rate-limit storms). Idempotent — only touches
rows still 'pending'; safe to re-run. The DB is the single source of truth.

Used two ways:
  1. Manually after a backfill:  mcp-server/.venv/bin/python scripts/drain_digests.py
  2. Daily cron (after the n8n 09:30 Gmail poll) — see crontab; runs under flock
     so a slow run never overlaps the next. Logs to data/digests/drain.log.

claude CLI must be on PATH (the cron line prepends ~/.local/bin). Config
(POSTGRES_URL, VOYAGE_API_KEY) auto-loads from ~/.env via legal_mcp.config.
"""

import asyncio
import os
import sys
import time
from datetime import datetime, timezone

# Ensure the local claude CLI is reachable even under a bare cron PATH.
os.environ["PATH"] = os.path.expanduser("~/.local/bin") + os.pathsep + os.environ.get("PATH", "")
sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "mcp-server", "src"))

from legal_mcp.services import db, digest_library as dl  # noqa: E402

CONCURRENCY = int(os.environ.get("DIGEST_DRAIN_CONCURRENCY", "3"))


async def main() -> int:
    pool = await db.get_pool()
    # get_pool() runs schema migrations first — incl. the V32 digest_kind backfill
    # that classifies legacy rows — so the failure check below is safe from the
    # very first run (no legacy row has digest_kind='').
    #
    # Self-heal: a successful enrich ALWAYS sets digest_kind (decision/announcement
    # /other). So a 'completed' row with digest_kind='' means the extraction never
    # landed (e.g. the local claude subscription window was exhausted) — reset to
    # 'pending' to retry (idempotent auto-resume). This correctly does NOT touch
    # announcements (digest_kind='announcement', legitimately no citation), which
    # the old "both fields empty" heuristic wrongly retried forever.
    healed = await pool.execute(
        "UPDATE digests SET extraction_status = 'pending' "
        "WHERE extraction_status = 'completed' "
        "AND coalesce(digest_kind,'') = '' "
        "AND coalesce(analysis_text,'') <> ''"
    )
    if healed and healed != "UPDATE 0":
        print(f"self-heal: reset unclassified (failed) digests → pending ({healed})", flush=True)
    # Self-heal stale 'processing': flock guarantees a single drainer, so at the
    # start of THIS run any row left 'processing' is from a previous run that was
    # killed mid-row (session/quota cutoff). Reset to 'pending' so it is retried.
    stale = await pool.execute(
        "UPDATE digests SET extraction_status = 'pending' WHERE extraction_status = 'processing'"
    )
    if stale and stale != "UPDATE 0":
        print(f"self-heal: reset stale processing → pending ({stale})", flush=True)
    rows = await pool.fetch(
        "SELECT id FROM digests WHERE extraction_status = 'pending' ORDER BY created_at"
    )
    ids = [r["id"] for r in rows]
    total = len(ids)
    stamp = datetime.now(timezone.utc).strftime("%Y-%m-%d %H:%M:%SZ")
    if not total:
        print(f"[{stamp}] no pending digests — nothing to drain", flush=True)
        await db.close_pool()
        return 0
    print(f"[{stamp}] draining {total} pending digests @ concurrency={CONCURRENCY}", flush=True)
    sem = asyncio.Semaphore(CONCURRENCY)
    state = {"done": 0, "ok": 0, "linked": 0, "fail": 0}
    t0 = time.time()

    async def work(did):
        async with sem:
            try:
                res = await dl.enrich_digest(did)
                state["ok"] += 1
                if res.get("linked_case_law_id"):
                    state["linked"] += 1
            except Exception as e:
                state["fail"] += 1
                print(f"  FAIL {did}: {type(e).__name__}: {e}", flush=True)
            state["done"] += 1
            if state["done"] % 20 == 0 or state["done"] == total:
                el = (time.time() - t0) / 60
                print(
                    f"  progress {state['done']}/{total} | ok={state['ok']} "
                    f"linked={state['linked']} fail={state['fail']} | {el:.1f}min",
                    flush=True,
                )

    await asyncio.gather(*[work(i) for i in ids])
    done_stamp = datetime.now(timezone.utc).strftime("%Y-%m-%d %H:%M:%SZ")
    print(
        f"[{done_stamp}] DONE {state['done']}/{total} | ok={state['ok']} "
        f"linked={state['linked']} fail={state['fail']} | {(time.time()-t0)/60:.1f}min",
        flush=True,
    )
    await db.close_pool()
    return 1 if state["fail"] else 0


if __name__ == "__main__":
    sys.exit(asyncio.run(main()))