import redis
import xml.etree.ElementTree as ET

from wcferry import Wcf


class GroupMemberChange:
    def __init__(self, wcf: Wcf, redis_pool: redis.ConnectionPool):
        self.wcf = wcf  # 假设 wcf 对象在此类中初始化
        self.redis_pool = redis_pool
        # 初始化本地缓存字典，使用 group_id 作为键
        self.local_membercounts = {}
        self.local_members = {}

    def _get_redis_connection(self):
        """从连接池获取 Redis 连接"""
        return redis.Redis(connection_pool=self.redis_pool)

    def get_current_members(self, group_id):
        """ 获取当前群成员信息 """
        print(f"Fetching current members for group_id: {group_id}")
        members = self.wcf.get_chatroom_members(group_id)  # 假设返回的数据格式是 {wxid1: 昵称1, wxid2: 昵称2, ...}
        print(f"Current members: {members}")
        return members

    def get_previous_data_from_redis(self, group_id):
        """ 从 Redis 获取上次的数据 """
        membercount_key = f"group:group_member_count:{group_id}"
        members_key = f"group:group_members:{group_id}"

        # 读取 Redis 中的数据
        print(f"Fetching previous data from Redis for group_id: {group_id}")
        membercount_previous = self._get_redis_connection().get(membercount_key)
        members_previous = self._get_redis_connection().hgetall(members_key)  # 获取上次的成员信息
        print(f"Previous membercount: {membercount_previous}, Previous members: {members_previous}")
        return membercount_previous, members_previous

    def process_message(self, group_id, xml_data_current):
        """ 处理消息并更新 Redis """
        root_current = ET.fromstring(xml_data_current)
        membercount_current = root_current.find('membercount').text

        result = []  # 初始化文案列表

        # 检查是否存在本地缓存数据，如果不存在，则从 Redis 获取
        if group_id not in self.local_membercounts or group_id not in self.local_members:
            print("No local data, fetching from Redis")
            membercount_previous, members_previous = self.get_previous_data_from_redis(group_id)

            # 如果没有上次的数据，说明是第一次处理，直接存储本次数据
            if membercount_previous is None or not members_previous:
                print("First time processing, saving current data to Redis")
                members_current = self.get_current_members(group_id)
                self._get_redis_connection().set(f"group:group_member_count:{group_id}", membercount_current)
                self._get_redis_connection().delete(f"group:group_members:{group_id}")
                self._get_redis_connection().hset(f"group:group_members:{group_id}",
                                                  mapping=members_current)  # 存储当前成员信息

                # 更新本地缓存
                self.local_membercounts[group_id] = membercount_current
                self.local_members[group_id] = members_current

                result.append("$NO_CHANGE$")
                return "\n".join(result)
            else:
                # 如果 Redis 中有数据，就更新本地缓存
                self.local_membercounts[group_id] = membercount_previous
                self.local_members[group_id] = members_previous
        else:
            # 使用本地缓存的数据进行比较
            membercount_previous = self.local_membercounts[group_id]
            members_previous = self.local_members[group_id]

        # 比较 membercount 是否发生变化
        if membercount_current != membercount_previous:
            print(f"Membercount changed: {membercount_previous} -> {membercount_current}")
            members_current = self.get_current_members(group_id)

            # TODO  如果用户达到了500人，则删除该群自动添加内容

            # 比较成员，仅使用 wxid 进行比较
            members_current_set = set(members_current.keys())
            members_previous_set = set(members_previous.keys())

            added_members = members_current_set - members_previous_set
            removed_members = members_previous_set - members_current_set

            # 添加变化成员的文案
            for wxid in added_members:
                nickname = members_current[wxid]
                result.append(f"检测到\n {nickname}（{wxid}）\n加入群聊")
            for wxid in removed_members:
                nickname = members_previous[wxid]
                result.append(f"检测到\n {nickname}（{wxid}）\n退出群聊")

            # 更新本地缓存
            print(f"Updating local cache with current membercount and members")
            self.local_membercounts[group_id] = membercount_current
            self.local_members[group_id] = members_current
            print(f"Current membercount: {membercount_current}, Current members: {members_current}")
            print(
                f"Local Current membercount: {self.local_membercounts[group_id]}, Local Current members: {self.local_members[group_id]}")

            # 更新 Redis 数据
            print(f"Updating Redis with current membercount and members")
            self._get_redis_connection.set(f"group:group_member_count:{group_id}", membercount_current)

            self._get_redis_connection.delete(f"group:group_members:{group_id}")
            # 更新 Redis 中的成员信息，确保在成员变化时也更新
            self._get_redis_connection.hset(f"group:group_members:{group_id}", mapping=members_current)

        else:
            result.append("$NO_CHANGE$")

        # 返回拼接后的结果
        return "\n".join(result)