from rest_framework import serializers
from .models import Teacher, Speciality, SchoolClass, Planning, LEVEL_CHOICES, Discount, Fee, PaymentPlan, PaymentMode, Establishment
from Auth.models import Profile
from N3wtSchool import settings, bdd
from django.utils import timezone
import pytz

class SpecialitySerializer(serializers.ModelSerializer):
    updated_date_formatted = serializers.SerializerMethodField()

    class Meta:
        model = Speciality
        fields = '__all__'

    def get_updated_date_formatted(self, obj):
        utc_time = timezone.localtime(obj.updated_date) # Convert to local time
        local_tz = pytz.timezone(settings.TZ_APPLI)
        local_time = utc_time.astimezone(local_tz)

        return local_time.strftime("%d-%m-%Y %H:%M")

class TeacherDetailSerializer(serializers.ModelSerializer):
    specialities = SpecialitySerializer(many=True, read_only=True)

    class Meta:
        model = Teacher
        fields = ['id', 'last_name', 'first_name', 'email', 'specialities']

class TeacherSerializer(serializers.ModelSerializer):
    specialities = serializers.PrimaryKeyRelatedField(queryset=Speciality.objects.all(), many=True, required=False)
    specialities_details = serializers.SerializerMethodField()
    associated_profile = serializers.PrimaryKeyRelatedField(queryset=Profile.objects.all(), required=True)
    updated_date_formatted = serializers.SerializerMethodField()
    droit = serializers.SerializerMethodField()

    class Meta:
        model = Teacher
        fields = '__all__'

    def create(self, validated_data):
        specialities_data = validated_data.pop('specialities', None)
        associated_profile = validated_data.pop('associated_profile', None)
        teacher = Teacher.objects.create(**validated_data)
        if specialities_data:
            teacher.specialities.set(specialities_data)
        if associated_profile:
            teacher.associated_profile = associated_profile
        teacher.save()
        return teacher

    def update(self, instance, validated_data):
        specialities_data = validated_data.pop('specialities', [])
        instance.last_name = validated_data.get('last_name', instance.last_name)
        instance.first_name = validated_data.get('first_name', instance.first_name)
        instance.email = validated_data.get('email', instance.email)
        instance.associated_profile = validated_data.get('associated_profile', instance.associated_profile)
        instance.save()
        if specialities_data:
            instance.specialities.set(specialities_data)
        return instance

    def get_updated_date_formatted(self, obj):
        utc_time = timezone.localtime(obj.updated_date) # Convert to local time
        local_tz = pytz.timezone(settings.TZ_APPLI)
        local_time = utc_time.astimezone(local_tz)

        return local_time.strftime("%d-%m-%Y %H:%M")

    def get_droit(self, obj):
        if obj.associated_profile:
            return obj.associated_profile.droit
        return None

    def get_specialities_details(self, obj): 
        return [{'id': speciality.id, 'name': speciality.name, 'color_code': speciality.color_code} for speciality in obj.specialities.all()]
                                                 
class PlanningSerializer(serializers.ModelSerializer):
    class Meta:
        model = Planning
        fields = ['id', 'level', 'schedule']

    def to_internal_value(self, data):
        internal_value = super().to_internal_value(data)
        internal_value['schedule'] = data.get('schedule', {})
        return internal_value

class SchoolClassSerializer(serializers.ModelSerializer):
    updated_date_formatted = serializers.SerializerMethodField()
    teachers = serializers.PrimaryKeyRelatedField(queryset=Teacher.objects.all(), many=True, required=False)
    establishment = serializers.PrimaryKeyRelatedField(queryset=Establishment.objects.all(), required=False)
    teachers_details = serializers.SerializerMethodField()

    class Meta:
        model = SchoolClass
        fields = '__all__'

    def create(self, validated_data):
        teachers_data = validated_data.pop('teachers', [])
        levels_data = validated_data.pop('levels', [])
        plannings_data = validated_data.pop('plannings', [])
        
        school_class = SchoolClass.objects.create(
            atmosphere_name=validated_data.get('atmosphere_name', ''),
            age_range=validated_data.get('age_range', []),
            number_of_students=validated_data.get('number_of_students', 0),
            teaching_language=validated_data.get('teaching_language', ''),
            school_year=validated_data.get('school_year', ''),
            levels=levels_data,
            type=validated_data.get('type', 1),
            time_range=validated_data.get('time_range', ['08:30', '17:30']),
            opening_days=validated_data.get('opening_days', [1, 2, 4, 5]),
            establishment=validated_data.get('establishment', None)
        )

        school_class.teachers.set(teachers_data)

        for planning_data in plannings_data:
            Planning.objects.create(
                school_class=school_class,
                level=planning_data['level'],
                schedule=planning_data.get('schedule', {})
            )

        return school_class

    def update(self, instance, validated_data):
        teachers_data = validated_data.pop('teachers', [])
        levels_data = validated_data.pop('levels', [])
        plannings_data = validated_data.pop('plannings', [])

        instance.atmosphere_name = validated_data.get('atmosphere_name', instance.atmosphere_name)
        instance.age_range = validated_data.get('age_range', instance.age_range)
        instance.number_of_students = validated_data.get('number_of_students', instance.number_of_students)
        instance.teaching_language = validated_data.get('teaching_language', instance.teaching_language)
        instance.school_year = validated_data.get('school_year', instance.school_year)
        instance.levels = levels_data
        instance.type = validated_data.get('type', instance.type)
        instance.time_range = validated_data.get('time_range', instance.time_range)
        instance.opening_days = validated_data.get('opening_days', instance.opening_days)
        instance.establishment = validated_data.get('establishment', instance.establishment)

        instance.save()
        instance.teachers.set(teachers_data)

        existing_plannings = {planning.level: planning for planning in instance.plannings.all()}

        for planning_data in plannings_data:
            level = planning_data['level']
            if level in existing_plannings:
                # Update existing planning
                planning = existing_plannings[level]
                planning.schedule = planning_data.get('schedule', planning.schedule)
                planning.save()
            else:
                # Create new planning if level not existing
                Planning.objects.create(
                    school_class=instance,
                    level=level,
                    schedule=planning_data.get('schedule', {})
                )

        return instance

    def get_teachers_details(self, obj): 
        return [{'id': teacher.id, 'last_name': teacher.last_name, 'first_name': teacher.first_name} for teacher in obj.teachers.all()]

    def get_updated_date_formatted(self, obj):
        utc_time = timezone.localtime(obj.updated_date)
        local_tz = pytz.timezone(settings.TZ_APPLI)
        local_time = utc_time.astimezone(local_tz)
        return local_time.strftime("%d-%m-%Y %H:%M")

class DiscountSerializer(serializers.ModelSerializer):
    updated_at_formatted = serializers.SerializerMethodField()
    establishment = serializers.PrimaryKeyRelatedField(queryset=Establishment.objects.all(), required=False)
    class Meta:
        model = Discount
        fields = '__all__'

    def get_updated_at_formatted(self, obj):
        utc_time = timezone.localtime(obj.updated_at)
        local_tz = pytz.timezone(settings.TZ_APPLI)
        local_time = utc_time.astimezone(local_tz)
        return local_time.strftime("%d-%m-%Y %H:%M")

class FeeSerializer(serializers.ModelSerializer):
    updated_at_formatted = serializers.SerializerMethodField()
    establishment = serializers.PrimaryKeyRelatedField(queryset=Establishment.objects.all(), required=False)

    class Meta:
        model = Fee
        fields = '__all__'

    def get_updated_at_formatted(self, obj):
        utc_time = timezone.localtime(obj.updated_at)
        local_tz = pytz.timezone(settings.TZ_APPLI)
        local_time = utc_time.astimezone(local_tz)
        return local_time.strftime("%d-%m-%Y %H:%M")

class PaymentPlanSerializer(serializers.ModelSerializer):
    class Meta:
        model = PaymentPlan
        fields = '__all__'

class PaymentModeSerializer(serializers.ModelSerializer):
    class Meta:
        model = PaymentMode
        fields = '__all__'

class EstablishmentSerializer(serializers.ModelSerializer):
    class Meta:
        model = Establishment
        fields = '__all__'