# -*- coding: utf-8 -*-
"""
通信中间件工厂
─────────────────────────────────────────────────────────────────
支持通过 URL 自动路由到对应适配器：

  redis://[:password@]host[:port][/db][?options]
  kafka://[user:password@]host[:port][/group_id][?options]
  dds://[domain_id@]host[:port][/topic_prefix][?options]

扩展新协议只需：
  1. 实现 CommBaseAdapter 子类
  2. 调用 CommAdapterFactory.register("scheme", YourAdapter)
─────────────────────────────────────────────────────────────────
"""

import logging
from typing import Type, Dict
from urllib.parse import urlparse, parse_qs, unquote

from uas.comm.base import CommBaseAdapter, ConnectionConfig

logger = logging.getLogger(__name__)


class CommAdapterFactory:
    """
    适配器工厂（注册表模式）
    线程安全，支持运行时动态注册新协议
    """

    _registry: Dict[str, Type[CommBaseAdapter]] = {}

    # ── 注册 ──────────────────────────────────────────────────────

    @classmethod
    def register(cls, scheme: str, adapter_cls: Type[CommBaseAdapter]) -> None:
        """
        注册新的协议适配器
        :param scheme:      协议名，如 "redis"、"kafka"、"mqtt"
        :param adapter_cls: CommBaseAdapter 子类
        """
        scheme = scheme.lower()
        if not issubclass(adapter_cls, CommBaseAdapter):
            raise TypeError(f"{adapter_cls} 必须继承自 CommBaseAdapter")
        cls._registry[scheme] = adapter_cls
        logger.info(f"✅ 已注册适配器: {scheme} -> {adapter_cls.__name__}")

    @classmethod
    def unregister(cls, scheme: str) -> None:
        cls._registry.pop(scheme.lower(), None)

    @classmethod
    def available_schemes(cls) -> list:
        return list(cls._registry.keys())

    # ── 创建 ──────────────────────────────────────────────────────

    @classmethod
    def create(cls, url: str) -> CommBaseAdapter:
        """
        根据 URL 自动创建对应适配器实例
        示例：
          redis://:mypassword@127.0.0.1:6379/0?socket_timeout=5
          kafka://broker1:9092/my-group?auto_offset_reset=earliest
          dds://0@localhost:7400/rt?reliability=RELIABLE
        """
        config = cls._parse_url(url)
        scheme = config.scheme

        if scheme not in cls._registry:
            raise ValueError(
                f"未知协议: '{scheme}'，已注册: {cls.available_schemes()}"
            )

        adapter_cls = cls._registry[scheme]
        logger.info(f"🔧 创建适配器: {adapter_cls.__name__}  url={url!r}")
        return adapter_cls(config)

    # ── URL 解析 ──────────────────────────────────────────────────

    @classmethod
    def _parse_url(cls, url: str) -> ConnectionConfig:
        """
        解析通用 URL 为 ConnectionConfig
        兼容以下格式：
          redis://[:password@]host[:port][/db]
          kafka://[user:pass@]host[:port][/group]
          dds://[domain@]host[:port][/prefix]
        """
        parsed = urlparse(url)
        scheme = parsed.scheme.lower()

        # 默认端口映射
        default_ports = {
            "redis": 6379,
            "kafka": 9092,
            "dds":   7400,
            "mqtt":  1883,
            "nats":  4222,
            "amqp":  5672,
        }

        host     = parsed.hostname or "localhost"
        port     = parsed.port or default_ports.get(scheme, 0)
        username = unquote(parsed.username or "")
        password = unquote(parsed.password or "")
        database = parsed.path.lstrip("/") if parsed.path else ""

        # 解析 query 参数（所有值展开为单值）
        raw_opts = parse_qs(parsed.query, keep_blank_values=True)
        options  = {k: v[0] if len(v) == 1 else v for k, v in raw_opts.items()}

        config = ConnectionConfig(
            scheme   = scheme,
            host     = host,
            port     = port,
            username = username,
            password = password,
            database = database,
            options  = options,
        )

        logger.debug(f"URL 解析结果: {config}")
        return config