from rest_framework import serializers
from account import models
from common import email


class ChoiceSerializer(serializers.ModelSerializer):
    class Meta:
        model = models.GroupChoice
        fields = ('choice', 'profile')


class ProfileSerializer_User(serializers.ModelSerializer):
    groups = serializers.SlugRelatedField(
        many=True,
        slug_field='choice',
        queryset=models.GroupChoice.objects.all())
    updated_at = serializers.DateTimeField(read_only=True)
    full_name = serializers.SerializerMethodField()
    bits = serializers.SerializerMethodField()

    class Meta:
        model = models.Profile
        read_only_fields = ('id', 'join_date', 'updated_at', 'full_name', )
        fields = (
            'id',
            'join_date',
            'updated_at',
            'nick',
            'signed',
            'groups',
            'motivation_about',
            'motivation_profession',
            'motivation_exercise',
            'full_name',
            'role',
            'bits'
        )

    def validate_updated_at(self, value):
        deadline = models.Deadline.get_solo().deadline
        if deadline is not None and value > deadline:
            raise serializers.ValidationError(
                "You cannot join after the deadline")
        return value

    def validate_role(self, value):
        modifier_role = self.context['request'].user.profile.role
        if value != modifier_role:
            raise serializers.ValidationError(
                "You don't have permission to change role")
        return value

    def validate_signed(self, value):
        if value is False:
            raise serializers.ValidationError("You cannot join without signed")
        return value

    def update(self, instance, validated_data):
        new_role = validated_data.get('role', instance.role)
        if instance.role != new_role:
            if new_role == 'Student':
                email.admitted(instance.user)
            if new_role == 'Denied':
                email.denied(instance.user)
        return super().update(instance, validated_data)

    def get_full_name(self, obj):
        return obj.full_name

    def get_bits(self, obj):
        if obj.homework_bits is None:
            return obj.events_visited
        return obj.homework_bits + obj.events_visited


class ProfileSerializer_Staff(serializers.ModelSerializer):
    groups = serializers.SlugRelatedField(
        many=True,
        slug_field='choice',
        queryset=models.GroupChoice.objects.all())
    updated_at = serializers.DateTimeField(read_only=True)
    full_name = serializers.SerializerMethodField()

    class Meta:
        model = models.Profile
        read_only_fields = ('id', 'join_date', 'updated_at', 'full_name', )
        fields = (
            'id',
            'join_date',
            'updated_at',
            'nick',
            'signed',
            'groups',
            'motivation_about',
            'motivation_profession',
            'motivation_exercise',
            'full_name',
            'role',
            'events_visited',
            'homework_bits'
        )

    def validate_updated_at(self, value):
        deadline = models.Deadline.get_solo().deadline
        if deadline is not None and value > deadline:
            raise serializers.ValidationError(
                "You cannot join after the deadline")
        return value

    def validate_role(self, value):
        return value

    def validate_signed(self, value):
        return value

    def update(self, instance, validated_data):
        new_role = validated_data.get('role', instance.role)
        if instance.role != new_role:
            if new_role == 'Student':
                email.admitted(instance.user)
            if new_role == 'Denied':
                email.denied(instance.user)
        return super().update(instance, validated_data)

    def get_full_name(self, obj):
        return obj.full_name


class MonitoringSerializer(serializers.ModelSerializer):
    full_name = serializers.SerializerMethodField()
    email = serializers.SerializerMethodField()

    class Meta:
        model = models.Profile
        read_only_fields = (
            'full_name',
            'email',
            'events_visited',
            'homework_bits',
        )
        fields = (
            'full_name',
            'email',
            'events_visited',
            'homework_bits',
        )

    def get_full_name(self, obj):
        return obj.full_name

    def get_email(self, obj):
        return obj.user.email