"""redis_worker.py — Фоновый обработчик очереди загрузок."""

import threading, time, base64, json
import db, mimeutil, parser as parser_mod, textify

def start_worker():
    """Запустить фоновый поток обработки очереди."""
    t = threading.Thread(target=_worker_loop, daemon=True)
    t.start()

def _worker_loop():
    from redis_client import pop as queue_pop
    while True:
        try:
            task = queue_pop(timeout=5)
            if task:
                _process(task)
        except Exception as e:
            time.sleep(1)

def _process(task):
    filename = task.get("filename", "")
    b64 = task.get("b64", "")
    mime = task.get("mime", "application/octet-stream")
    cid = task.get("cid", "")

    if not filename or not b64:
        return

    # Декодировать и сохранить в БД
    file_bytes = base64.b64decode(b64)

    conn, err = db.connect()
    if err:
        return
    try:
        cur = conn.cursor()
        cur.execute(
            "INSERT INTO documents (filename, mime_type, original_bytes, original_b64, status) VALUES (%s,%s,%s,%s,'uploaded')",
            (filename, mime, file_bytes, b64),
        )
        cur.execute("SELECT id FROM documents WHERE filename=%s AND status='uploaded' ORDER BY created_at DESC LIMIT 1", (filename,))
        row = cur.fetchone()
        doc_id = row[0] if row else None
        if doc_id:
            cur.execute(
                "INSERT INTO supplements (contract_id, document_id, type) VALUES (%s,%s,'initial')",
                (cid, str(doc_id)),
            )

        # Парсинг
        pr = parser_mod.parse(file_bytes, mime)
        elements = pr.get("elements", [])
        if mime == "application/zip" and "files" in pr:
            for zf in pr["files"]:
                elements.extend(zf.get("elements", []))
        text = textify.to_text(elements) if elements else ""

        cur.execute(
            "UPDATE documents SET parsed_text=%s, elements_json=%s, status='parsed' WHERE id=%s",
            (text, json.dumps(elements, ensure_ascii=False), str(doc_id)),
        )
        conn.commit()
        cur.close()
    except Exception as e:
        try: conn.rollback()
        except: pass
    finally:
        db.put_conn(conn)