#!/usr/bin/env python3
# INFRA:DEAD rds -- AWS RDS is gone. Any file referencing rds_connect.py or this hostname is stale and must be ported.
"""Batch-embed ENE artifacts missing embeddings and emit a JSON receipt."""

from __future__ import annotations

import argparse
import json
import os
import sys
import time
from pathlib import Path
from typing import Any
from urllib import request

from rds_connect import connect_rds
from shim.utils import sha256_text, utc_now

BATCH_SIZE = 50
TOKEN_REFRESH_SEC = 600

HOST = os.environ.get("RDS_HOST", "100.92.88.64")
PORT = int(os.environ.get("RDS_PORT", "5432"))
USER = os.environ.get("RDS_USER", "postgres")
DB = os.environ.get("RDS_DB", os.environ.get("RDS_DBNAME", "postgres"))

OLLAMA_URL = os.environ.get("OLLAMA_URL", "http://100.85.244.73:11434").rstrip("/")
EMBED_MODEL = os.environ.get("EMBED_MODEL", "nomic-embed-text")


def fetch_batch(cur, batch_size: int) -> list[tuple[Any, str, str]]:
    cur.execute(
        "SELECT id, path, content FROM ene.artifacts "
        "WHERE embedding IS NULL AND content IS NOT NULL AND content != '' "
        "AND kind NOT IN ('verilog', 'shader', 'schema', 'binary') "
        "ORDER BY path LIMIT %s",
        (batch_size,),
    )
    return cur.fetchall()


def generate_embedding(text: str) -> list[float] | None:
    payload = json.dumps({"model": EMBED_MODEL, "prompt": text[:2048]}).encode("utf-8")
    req = request.Request(
        f"{OLLAMA_URL}/api/embeddings",
        data=payload,
        headers={"Content-Type": "application/json"},
    )
    with request.urlopen(req, timeout=30) as resp:
        data = json.loads(resp.read())
    embedding = data.get("embedding")
    if not isinstance(embedding, list):
        return None
    return embedding


def pgvector_literal(values: list[float]) -> str:
    return "[" + ",".join(format(value, ".16g") for value in values) + "]"


def build_receipt(
    *,
    started_at: str,
    processed: int,
    embedded: int,
    failed: list[dict[str, str]],
    dry_run: bool,
    limit: int | None,
    duration_sec: float,
) -> dict[str, Any]:
    receipt: dict[str, Any] = {
        "schema": "ene_artifact_embedding_batch_receipt_v1",
        "version": "1.0.0",
        "generated_at_utc": utc_now(),
        "started_at_utc": started_at,
        "duration_ms": int(duration_sec * 1000),
        "dry_run": dry_run,
        "limit": limit,
        "rds_host": HOST,
        "rds_db": DB,
        "ollama_url": OLLAMA_URL,
        "embed_model": EMBED_MODEL,
        "processed_count": processed,
        "embedded_count": embedded,
        "failed_count": len(failed),
        "failures": failed[:20],
    }
    preimage = {k: v for k, v in receipt.items() if k != "receipt_hash"}
    receipt["receipt_hash"] = sha256_text(json.dumps(preimage, sort_keys=True))
    return receipt


def write_receipt(receipt: dict[str, Any], path: str | None) -> None:
    encoded = json.dumps(receipt, sort_keys=True)
    print(encoded)
    if path:
        out = Path(path)
        out.parent.mkdir(parents=True, exist_ok=True)
        out.write_text(encoded + "\n", encoding="utf-8")


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--batch-size", type=int, default=BATCH_SIZE)
    parser.add_argument("--limit", type=int, default=None)
    parser.add_argument("--dry-run", action="store_true")
    parser.add_argument("--receipt-out")
    return parser.parse_args()


def main() -> int:
    args = parse_args()
    if args.batch_size <= 0:
        raise SystemExit("--batch-size must be positive")

    started_at = utc_now()
    started = time.time()
    conn = connect_rds()
    next_refresh = time.time() + TOKEN_REFRESH_SEC
    cur = conn.cursor()
    processed = 0
    embedded = 0
    failed: list[dict[str, str]] = []
    attempted_ids: set[str] = set()

    try:
        rows = fetch_batch(cur, args.batch_size)
        while rows and (args.limit is None or processed < args.limit):
            rows = [row for row in rows if str(row[0]) not in attempted_ids]
            if not rows:
                break

            if os.environ.get("RDS_IAM", "1") == "1" and time.time() > next_refresh:
                conn.close()
                conn = connect_rds()
                cur = conn.cursor()
                next_refresh = time.time() + TOKEN_REFRESH_SEC

            for aid, path, content in rows:
                if args.limit is not None and processed >= args.limit:
                    break
                attempted_ids.add(str(aid))
                processed += 1
                try:
                    if args.dry_run:
                        continue
                    embedding = generate_embedding(content)
                    if not embedding:
                        failed.append({"path": path, "error": "embedding response missing vector"})
                        continue
                    cur.execute(
                        "UPDATE ene.artifacts SET embedding = %s::vector WHERE id = %s",
                        (pgvector_literal(embedding), aid),
                    )
                    embedded += 1
                except Exception as exc:  # noqa: BLE001 - receipt records per-row failure.
                    failed.append({"path": path, "error": str(exc)})

            if args.dry_run:
                conn.rollback()
            else:
                conn.commit()
            rows = fetch_batch(cur, args.batch_size)
    finally:
        cur.close()
        conn.close()

    receipt = build_receipt(
        started_at=started_at,
        processed=processed,
        embedded=embedded,
        failed=failed,
        dry_run=args.dry_run,
        limit=args.limit,
        duration_sec=time.time() - started,
    )
    write_receipt(receipt, args.receipt_out)
    return 0 if not failed else 2


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