from rest_framework import serializers
from rest_framework.authtoken.models import Token
from django.contrib.auth.models import Group
from django.contrib.auth.password_validation import validate_password
from django.utils.translation import gettext_lazy as _
from apps.account.models import User
from utils import FileFieldSerializer, absolute_url
from utils.validators import validate_type_code



class UserProfileSerializer(serializers.ModelSerializer):
    avatar = FileFieldSerializer(required=False, allow_null=True)
    password = serializers.CharField(write_only=True, required=False, validators=[validate_password])
    fullname = serializers.CharField(required=False)
    gender = serializers.ChoiceField(
        choices=User.GenderChoices.choices,
        required=False,
        help_text="Select the user's gender."
    )
    fcm = serializers.CharField(required=False, help_text="Firebase Cloud Messaging token.")
    saved_location = serializers.SerializerMethodField()

    class Meta:
        model = User
        fields = ['id', 'device_id', 'fcm', 'fullname', 'slug', 'avatar', 'email', 'phone_number', 'password', 'info', 'skill', 'city', 'country', 'birthdate', 'gender', 'saved_location']
        read_only_fields = ['email', 'info', 'skill', 'device_id', 'slug', 'saved_location']
    
    def get_saved_location(self, obj):
        # Check if user is authenticated and has location_history attribute
        if not obj.is_authenticated or not hasattr(obj, 'location_history'):
            return None
            
        last_location = obj.location_history.order_by('-at_time').first()
        if last_location:
            return {
                'lat': last_location.lat,
                'lon': last_location.lon,
                'city': last_location.city,
                'country': last_location.country,
                'timezone': last_location.timezone,
                'selected_manually': last_location.selected_manually,
                'at_time': last_location.at_time,
            }
        return None

    # def validate_email(self, value):
    #     if User.objects.filter(email=value).exists():
    #         raise serializers.ValidationError("This email is already registered.")
    #     return value

    def update(self, instance, validated_data):
        # Pop the password from the data to handle it separately
        password = validated_data.pop('password', None)

        # Use the default update logic for all other fields
        for attr, value in validated_data.items():
            if value is not None:
                setattr(instance, attr, value)

        # If a new password was provided, hash and set it correctly
        if password:
            instance.set_password(password)

        instance.save()
        return instance


class UserRegisterSerializer(serializers.ModelSerializer):
    fcm = serializers.CharField(required=False, allow_blank=True, allow_null=True)
    device_id = serializers.CharField(required=False, allow_blank=True, allow_null=True, write_only=True)
    email = serializers.EmailField()
      
    class Meta:
        model = User
        fields = ['id','fullname', 'email', 'fcm', 'device_id']
        extra_kwargs = {
            'fullname': {'required': True,},
            'email': {'required': True,},
        }
    
    def create(self, validated_data):
        device_id = validated_data.pop('device_id', None)
        user = super().create(validated_data)
        if device_id:
            user.device_id = device_id
            user.save()
        return user

    def validate_email(self, value):
        normalized_email = User.objects.normalize_email(value)
        if User.objects.filter(email=normalized_email).exists():
            raise serializers.ValidationError("This email is already registered.")
        return normalized_email

    

class UserVerifySerializer(serializers.Serializer):
    code = serializers.CharField(max_length=5, validators=[validate_type_code])
    email = serializers.EmailField()
    device_id = serializers.CharField(max_length=255, required=False)
    
    def validate_email(self, value):
        """
        Normalize the email to ensure the Redis key matches correctly.
        """
        return User.objects.normalize_email(value)
    

class UserLoginSerializer(serializers.Serializer):
    password = serializers.CharField(write_only=True)
    token = serializers.CharField(allow_null=True, read_only=True, required=False)
    fullname = serializers.CharField(allow_null=True, read_only=True, required=False)
    avatar = serializers.CharField(allow_null=True, read_only=True, required=False)
    email = serializers.EmailField(write_only=True)
    password = serializers.CharField(style={'input_type': 'password'}, trim_whitespace=False)
    fcm = serializers.CharField(required=False)
    device_id = serializers.CharField(required=False)
    timezone = serializers.CharField(required=False, allow_null=True, allow_blank=True)

    def validate(self, data):
        # Custom validation logic can be added here if needed
        # data.pop('fcm', None)        
        # data.pop('device_id', None)        
        return data
    def validate_email(self, value):
        """
        Normalize email for case-insensitive login.
        """
        return User.objects.normalize_email(value)


# class UserLoginSerializer(serializers.Serializer):
#     password = serializers.CharField(write_only=True)
#     token = serializers.CharField(allow_null=True, read_only=True, required=False)
#     fullname = serializers.CharField(allow_null=True, read_only=True, required=False)
#     avatar = serializers.CharField(allow_null=True, read_only=True, required=False)
#     email = serializers.EmailField(write_only=True)
#     password = serializers.CharField(style={'input_type': 'password'}, trim_whitespace=False)
#     fcm = serializers.CharField(required=False)
#     device_id = serializers.CharField(required=False)
#     timezone = serializers.CharField(required=False, allow_null=True, allow_blank=True)


        
        
# class UserRecoverPasswordSerializer(serializers.ModelSerializer):
#     email = serializers.EmailField()
    
#     class Meta:
#         model = User
#         fields = ['email',]
#         extra_kwargs = {
#             'email': {'required': True,},
#         }

class UserRecoverPasswordSerializer(serializers.Serializer):
    """
    Validates that an email is provided and is in a valid format
    without checking for database uniqueness.
    """
    email = serializers.EmailField(required=True)

    def validate_email(self, value):
        """
        Normalize the email address to ensure case-insensitive lookups.
        """
        return User.objects.normalize_email(value)
    
class UserResetPasswordSerializer(serializers.ModelSerializer):
    password = serializers.CharField(write_only=True)

    class Meta:
        model = User
        fields = ['password', ]
        extra_kwargs = {
            'password': {'required': True,},
        }




class UserGuestSerializer(serializers.ModelSerializer):
    lat = serializers.CharField(max_length=255, allow_null=True, allow_blank=True, required=False)
    lon = serializers.CharField(max_length=255, allow_null=True, allow_blank=True, required=False)
    fcm = serializers.CharField(required=False)
    device_id = serializers.CharField(required=False)
    device_os = serializers.ChoiceField(choices=User.DeviceOs.choices, required=False)
    timezone = serializers.CharField(required=False, allow_null=True, allow_blank=True)

    class Meta:
        model = User
        fields = ['device_id', 'fcm', 'device_os', 'lat', 'lon', 'timezone']

    def validate(self, data):
        # Make sure at least device_id is provided
        if not data.get('device_id'):
            raise serializers.ValidationError({"device_id": "Device ID is required for guest users."})

        return data

class WebUserGuestSerializer(serializers.ModelSerializer):

    user_agent = serializers.CharField(required=False, allow_null=True, allow_blank=True)
    client_ip = serializers.CharField(required=False, allow_null=True, allow_blank=True)
    timezone = serializers.CharField(required=False, allow_null=True, allow_blank=True)

    class Meta:
        model = User
        fields = ['user_agent', 'client_ip', 'timezone', 'device_id', 'device_os']

    def validate(self, data):
        # Ensure device_id is provided (generated by view)
        if not data.get('device_id'):
            raise serializers.ValidationError({"device_id": "Device ID is required for web guest users."})
        return data



class UserFCMSerializer(serializers.ModelSerializer):
    class Meta:
        model = User
        fields = ['fcm']


class AdminUserSerializer(serializers.ModelSerializer):
    avatar = FileFieldSerializer(required=False, allow_null=True)
    password = serializers.CharField(write_only=True, required=False, validators=[validate_password])
    email = serializers.EmailField(required=True)
    auth_token = serializers.SerializerMethodField()
    plain_password = serializers.SerializerMethodField()

    def get_auth_token(self, obj):
        token = Token.objects.filter(user=obj).first()
        return token.key if token else None

    def get_plain_password(self, obj):
        request = self.context.get('request')
        if request and request.user and (request.user.is_superuser or request.user.user_type in ['super_admin', 'admin']):
            return obj.get_plain_password()
        return None

    class Meta:
        model = User
        fields = [
            'id', 'fullname', 'email', 'phone_number', 'password', 'avatar',
            'gender', 'birthdate', 'info', 'skill', 'city', 'country',
            'device_id', 'device_os', 'user_agent', 'client_ip', 'fcm',
            'user_type', 'is_active', 'is_staff', 'is_superuser',
            'date_joined', 'last_login', 'auth_token', 'plain_password'
        ]
        read_only_fields = ['id', 'date_joined', 'last_login', 'auth_token', 'device_id', 'device_os', 'user_agent', 'client_ip']

    ROLE_GROUP_MAP = {
        User.UserType.STUDENT: "Student Group",
        User.UserType.PROFESSOR: "Professor Group",
        User.UserType.ADMIN: "Admin Group",
        User.UserType.SUPER_ADMIN: "Super Admin Group",
        User.UserType.CONSULTANT: "Consultant Group",
    }
    PANEL_GROUPS = {"Professor Group", "Admin Group", "Super admin Group", "Super Admin Group"}

    def _ensure_group(self, instance, group_name):
        group, _ = Group.objects.get_or_create(name=group_name)
        instance.groups.add(group)

    def _remove_groups(self, instance, group_names):
        if not group_names:
            return
        instance.groups.remove(*Group.objects.filter(name__in=group_names))

    def _normalize_role_access(self, instance, requested_user_type):
        if not requested_user_type:
            return

        requested_user_type = str(requested_user_type)

        if requested_user_type == User.UserType.SUPER_ADMIN:
            instance.is_staff = True
            instance.is_superuser = True
            self._ensure_group(instance, "Super Admin Group")
            self._remove_groups(instance, {"Professor Group", "Admin Group", "Super admin Group"})
            return

        if requested_user_type == User.UserType.PROFESSOR:
            instance.is_staff = False
            instance.is_superuser = False
            self._ensure_group(instance, "Professor Group")
            self._remove_groups(instance, {"Admin Group", "Super admin Group", "Super Admin Group"})
            return

        if requested_user_type == User.UserType.ADMIN:
            instance.is_staff = False
            instance.is_superuser = False
            self._ensure_group(instance, "Admin Group")
            self._remove_groups(instance, {"Professor Group", "Super admin Group", "Super Admin Group"})
            return

        if requested_user_type == User.UserType.STUDENT:
            instance.is_staff = False
            instance.is_superuser = False
            self._ensure_group(instance, "Student Group")
            self._remove_groups(instance, self.PANEL_GROUPS)
            return

        if requested_user_type == User.UserType.CONSULTANT:
            instance.is_staff = False
            instance.is_superuser = False
            self._ensure_group(instance, "Consultant Group")
            self._remove_groups(instance, self.PANEL_GROUPS)
            return

        if requested_user_type == User.UserType.CLIENT:
            instance.is_staff = False
            instance.is_superuser = False
            self._remove_groups(instance, self.PANEL_GROUPS)

    def create(self, validated_data):
        password = validated_data.pop('password', None)
        user = User(**validated_data)
        if password:
            user.set_password(password)
            user.set_plain_password(password)
        else:
            user.set_unusable_password()
        user.save()
        self._normalize_role_access(user, validated_data.get('user_type', user.user_type))
        user.save()
        return user

    def update(self, instance, validated_data):
        password = validated_data.pop('password', None)
        user = super().update(instance, validated_data)
        self._normalize_role_access(user, validated_data.get('user_type', user.user_type))
        if password:
            user.set_password(password)
            user.set_plain_password(password)
        user.save()
        return user