from rest_framework import serializers
from django.contrib.auth import authenticate
from django.contrib.auth.password_validation import validate_password
from .models import User


class UserRegistrationSerializer(serializers.ModelSerializer):
    """用户注册序列化器"""
    password = serializers.CharField(write_only=True, validators=[validate_password])
    password_confirm = serializers.CharField(write_only=True)
    
    class Meta:
        model = User
        fields = ('username', 'email', 'first_name', 'last_name', 
                 'phone', 'department', 'position', 'password', 'password_confirm')
    
    def validate(self, attrs):
        if attrs['password'] != attrs['password_confirm']:
            raise serializers.ValidationError("密码不一致")
        return attrs
    
    def create(self, validated_data):
        validated_data.pop('password_confirm', None)
        user = User.objects.create_user(**validated_data)
        return user


class UserLoginSerializer(serializers.Serializer):
    """用户登录序列化器"""
    username = serializers.CharField()
    password = serializers.CharField(write_only=True)
    
    def validate(self, attrs):
        username = attrs.get('username')
        password = attrs.get('password')
        
        if username and password:
            user = authenticate(username=username, password=password)
            if not user:
                raise serializers.ValidationError('用户名或密码错误')
            if not user.is_active:
                raise serializers.ValidationError('用户账号已被禁用')
            attrs['user'] = user
        else:
            raise serializers.ValidationError('用户名和密码不能为空')
        
        return attrs


class UserProfileSerializer(serializers.ModelSerializer):
    """用户信息序列化器"""
    full_name = serializers.SerializerMethodField()
    
    class Meta:
        model = User
        fields = ('id', 'username', 'email', 'first_name', 'last_name', 
                 'full_name', 'phone', 'department', 'position', 'avatar',
                 'is_staff', 'is_superuser', 'date_joined')
        read_only_fields = ('id', 'username', 'is_staff', 'is_superuser', 'date_joined')
    
    def get_full_name(self, obj):
        return f'{obj.first_name} {obj.last_name}'.strip() or obj.username


class UserListSerializer(serializers.ModelSerializer):
    """用户列表序列化器"""
    full_name = serializers.SerializerMethodField()
    
    class Meta:
        model = User
        fields = ('id', 'username', 'full_name', 'email', 'department', 'position', 'is_active')
    
    def get_full_name(self, obj):
        return f'{obj.first_name} {obj.last_name}'.strip() or obj.username