"""v2/chunk_api.py — Приём чанков по 30KB, финализация."""

import sys, os, base64, hashlib, logging
sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..', 'site'))
import db, mimeutil
sys.path.insert(0, os.path.dirname(__file__))
import init as v2

from flask import Blueprint, request, jsonify

bp = Blueprint("v2", __name__, url_prefix="/v2")

@bp.route("/chunk", methods=["POST"])
def receive_chunk():
    body = request.get_json(silent=True) or {}
    if not body.get("upload_id") or not body.get("data"):
        return jsonify({"ok": False, "error": "missing fields"}), 400
    try:
        v2.store_chunk(body["upload_id"], int(body.get("index", 0)), body["data"])
        return jsonify({"ok": True, "received": int(body.get("index", 0))})
    except Exception as e:
        return jsonify({"ok": False, "error": str(e)}), 500

@bp.route("/finalize", methods=["POST"])
def finalize_upload():
    body = request.get_json(silent=True) or {}
    upload_id = body.get("upload_id", "")
    filename = body.get("filename", "")
    total = int(body.get("total", 0))
    checksum = body.get("checksum", "")

    if not all([upload_id, filename, total]):
        return jsonify({"ok": False, "error": "missing fields"}), 400

    chunks = v2.get_chunks(upload_id)
    if len(chunks) != total:
        return jsonify({"ok": False, "error": f"expected {total}, got {len(chunks)}"}), 409

    try:
        file_bytes = b"".join(base64.b64decode(c) for c in chunks)
    except Exception as e:
        return jsonify({"ok": False, "error": f"decode: {e}"}), 422

    if checksum and hashlib.md5(file_bytes).hexdigest() != checksum:
        return jsonify({"ok": False, "error": "checksum mismatch"}), 422

    mime = mimeutil.guess_mime(filename) or "application/octet-stream"

    # Сохранить в БД
    conn, err = db.connect()
    if err:
        return jsonify({"ok": False, "error": f"db: {err}"}), 500
    try:
        cur = conn.cursor()
        cur.execute(
            "INSERT INTO contracts (number, client) VALUES (%s,%s) RETURNING id",
            ("б/н " + __import__("datetime").datetime.now().strftime("%Y%m%d-%H%M"), ""),
        )
        cid = cur.fetchone()[0]
        cur.execute(
            "INSERT INTO documents (filename, mime_type, original_bytes, status) VALUES (%s,%s,%s,'uploaded')",
            (filename, mime, file_bytes),
        )
        cur.execute("SELECT id FROM documents WHERE filename=%s ORDER BY created_at DESC LIMIT 1", (filename,))
        doc_id = cur.fetchone()[0]
        cur.execute("INSERT INTO supplements (contract_id, document_id, type) VALUES (%s,%s,'initial')", (str(cid), str(doc_id)))
        conn.commit()
        cur.close()
    finally:
        db.put_conn(conn)

    v2.delete_chunks(upload_id)
    v2.push_finalize({"doc_id": str(doc_id), "filename": filename, "mime_type": mime})

    return jsonify({"ok": True, "contract_id": str(cid), "doc_id": str(doc_id)})