from decimal import Decimal
from rest_framework import serializers
from drf_spectacular.utils import extend_schema_field
from apps.donations.models import (
    DonationCampaign,
    DonationTransaction,
    CampaignCategory,
    CampaignPriority,
    PaymentStatus,
)


class DonationTransactionSerializer(serializers.ModelSerializer):
    campaign_title = serializers.CharField(source='campaign.title', read_only=True)

    class Meta:
        model = DonationTransaction
        fields = [
            'id', 'transaction_reference', 'campaign',
            'campaign_title', 'donor_name', 'amount',
            'currency', 'payment_status', 'created_at',
        ]
        read_only_fields = ['id', 'transaction_reference', 'payment_status', 'created_at']


class DonationCampaignListSerializer(serializers.ModelSerializer):
    institution_name = serializers.CharField(source='institution.name', read_only=True)
    progress_percentage = serializers.IntegerField(read_only=True)
    donors_count = serializers.IntegerField(read_only=True)

    class Meta:
        model = DonationCampaign
        fields = [
            'id', 'title', 'slug', 'description',
            'target_amount', 'raised_amount', 'currency',
            'category', 'priority', 'cover_image',
            'institution', 'institution_name', 'organization_name',
            'deadline', 'progress_percentage', 'donors_count',
            'is_featured', 'created_at',
        ]


class DonationCampaignDetailSerializer(serializers.ModelSerializer):
    institution_name = serializers.CharField(source='institution.name', read_only=True)
    progress_percentage = serializers.IntegerField(read_only=True)
    donors_count = serializers.IntegerField(read_only=True)
    recent_donations = serializers.SerializerMethodField()

    class Meta:
        model = DonationCampaign
        fields = [
            'id', 'title', 'slug', 'description',
            'target_amount', 'raised_amount', 'currency',
            'category', 'priority', 'cover_image',
            'institution', 'institution_name', 'organization_name',
            'deadline', 'progress_percentage', 'donors_count',
            'is_featured', 'recent_donations', 'created_at', 'updated_at',
        ]

    @extend_schema_field(DonationTransactionSerializer(many=True))
    def get_recent_donations(self, obj):
        recent = obj.transactions.filter(payment_status=PaymentStatus.COMPLETED)[:5]
        return DonationTransactionSerializer(recent, many=True).data


class DonationContributeRequestSerializer(serializers.Serializer):
    amount = serializers.DecimalField(max_digits=12, decimal_places=2, min_value=Decimal('1.00'))
    donor_name = serializers.CharField(required=False, default='Anonymous Donor', allow_blank=True)
    donor_email = serializers.EmailField(required=False, allow_blank=True, allow_null=True)