"""SQLite 存储：表结构与插入字段由协议 schema 自动生成。

消息类 -> 表名 映射见 TABLE_NAMES；插入时从 msg.to_dict() 取字段，
与 protocol.py 保持单一数据源，避免手写列定义漂移。
"""

import sqlite3
import threading

from . import protocol


def _table_name(msg_cls):
    name = msg_cls.__name__
    if name.startswith("MsgDis"):
        name = name[len("MsgDis"):]
    # MsgDisHighVolBusFb -> msg_disHighVolBusFbMsg
    return "msg_dis" + name + "Msg"


TABLE_NAMES = {cls: _table_name(cls) for cls in protocol.ALL_MESSAGES.values()}


class DB:
    def __init__(self, db_path):
        self.db_path = db_path
        self.conn = None
        self.lock = threading.Lock()

    def connect(self):
        self.conn = sqlite3.connect(self.db_path, check_same_thread=False)
        self.conn.row_factory = sqlite3.Row
        self.create_tables()

    def disconnect(self):
        """与 close() 等价，兼容历史调用。"""
        self.close()

    def close(self):
        if self.conn is not None:
            self.conn.close()
            self.conn = None

    def create_tables(self):
        with self.lock:
            cursor = self.conn.cursor()
            for msg_cls, table in TABLE_NAMES.items():
                cols = ", ".join(f'"{name}" INTEGER' for name in msg_cls.field_names())
                cursor.execute(
                    f'CREATE TABLE IF NOT EXISTS "{table}" ('
                    f'id INTEGER PRIMARY KEY AUTOINCREMENT, '
                    f'timestamp DATETIME DEFAULT (datetime(\'now\', \'localtime\')), '
                    f'{cols})'
                )
            self.conn.commit()

    def insert_message(self, msg):
        """按消息类型路由到对应数据表。返回 True/False。"""
        table = TABLE_NAMES.get(msg.__class__)
        if table is None:
            return False
        return self.insert_dict(table, msg.to_dict())

    def insert_dict(self, table, data_dict):
        with self.lock:
            try:
                if self.conn is None:
                    self.connect()
                if self.conn is None:
                    return False
                columns = ", ".join(f'"{c}"' for c in data_dict.keys())
                placeholders = ", ".join(["?"] * len(data_dict))
                query = f'INSERT INTO "{table}" ({columns}) VALUES ({placeholders})'
                self.conn.cursor().execute(query, list(data_dict.values()))
                self.conn.commit()
                return True
            except sqlite3.Error:
                return False