import os
import sqlite3
import pymysql
import sys
from typing import List, Optional
from config import DB_HOST, DB_PORT, DB_USER, DB_PASSWORD, DB_NAME, DB_TABLE, PROCESS_DB_THREADS

BASE_DIR = os.path.dirname(os.path.abspath(__file__))


def get_thread_indexes() -> Optional[List[int]]:
    if PROCESS_DB_THREADS is None:
        return None
    if isinstance(PROCESS_DB_THREADS, (list, tuple)) and len(PROCESS_DB_THREADS) == 0:
        return None
    return list(PROCESS_DB_THREADS)


def create_table_if_not_exists(conn):
    sql = f"""
    CREATE TABLE IF NOT EXISTS `{DB_TABLE}` (
      `id` INT AUTO_INCREMENT PRIMARY KEY,
      `softid` INT NOT NULL,
      `softname` TEXT,
      `softdate` DATE,
      `createtime` DATETIME,
      UNIQUE KEY `uniq_softid` (`softid`)
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;
    """
    with conn.cursor() as cur:
        cur.execute(sql)
    conn.commit()


def import_db(sqlite_path: str, mysql_conn, batch_size: int = 1000):
    if not os.path.exists(sqlite_path):
        print(f"Skipping missing sqlite file: {sqlite_path}")
        return 0

    sconn = sqlite3.connect(sqlite_path)
    scur = sconn.cursor()
    try:
        scur.execute('SELECT softid, softname, softdate, createtime FROM softinfo')
    except Exception as e:
        print(f"Error reading {sqlite_path}: {e}")
        sconn.close()
        return 0

    rows = scur.fetchall()
    total = len(rows)
    if total == 0:
        print(f"No rows in {sqlite_path}")
        sconn.close()
        return 0

    insert_sql = f"INSERT INTO `{DB_TABLE}` (softid, softname, softdate, createtime) VALUES (%s, %s, %s, %s) ON DUPLICATE KEY UPDATE softname=VALUES(softname), softdate=VALUES(softdate), createtime=VALUES(createtime)"

    inserted = 0
    batch = []
    for r in rows:
        # sqlite may store None for softname etc.
        batch.append((r[0], r[1], r[2], r[3]))
        if len(batch) >= batch_size:
            with mysql_conn.cursor() as cur:
                cur.executemany(insert_sql, batch)
            mysql_conn.commit()
            inserted += len(batch)
            print(f"Inserted {inserted}/{total} from {os.path.basename(sqlite_path)}")
            batch = []

    if batch:
        with mysql_conn.cursor() as cur:
            cur.executemany(insert_sql, batch)
        mysql_conn.commit()
        inserted += len(batch)
        print(f"Inserted {inserted}/{total} from {os.path.basename(sqlite_path)}")

    sconn.close()
    return inserted


def main():
    indexes = get_thread_indexes()

    # Connect to MySQL
    try:
        mconn = pymysql.connect(host=DB_HOST, port=DB_PORT, user=DB_USER, password=DB_PASSWORD, database=DB_NAME, charset='utf8mb4', autocommit=False)
    except Exception as e:
        print(f"Failed to connect to MySQL: {e}")
        sys.exit(1)

    try:
        create_table_if_not_exists(mconn)

        # Discover sqlite files to process
        files = []
        if indexes is None:
            # collect all softlist_*.db files in BASE_DIR
            for fname in os.listdir(BASE_DIR):
                if fname.startswith('softlist_') and fname.endswith('.db'):
                    files.append(os.path.join(BASE_DIR, fname))
        else:
            for idx in indexes:
                fname = f'softlist_{idx}.db'
                files.append(os.path.join(BASE_DIR, fname))

        if not files:
            print("No sqlite files to process.")
            return

        total_inserted = 0
        for f in files:
            print(f"Processing: {f}")
            inserted = import_db(f, mconn)
            total_inserted += inserted

        print(f"Done. Total rows inserted/updated: {total_inserted}")

    finally:
        mconn.close()


if __name__ == '__main__':
    main()