# python
from decimal import Decimal

# django
from django.db import transaction
# rest framework
from rest_framework import serializers

# accounts
from core.apps.accounts.models import User
# counterparty
from core.apps.counterparty.models import Counterparty
from core.apps.counterparty.serializers.counterparty import CounterpartySerializer
# finance
from core.apps.finance.models import Expence
# orders
from core.apps.orders.models import DeletedParty, Order, Party, PartyAmount
from core.apps.orders.serializers.order import (
    MultipleOrderAddSerializer,
    OrderListSerializer,
)
# products
from core.apps.products.models import Product, Unity
# projects
from core.apps.projects.models import Project, ProjectFolder
# shared
from core.apps.shared.models import UsdCourse
# wherehouse
from core.apps.wherehouse.models import WhereHouse


class PartyCreateSerializer(serializers.Serializer):
    resources = MultipleOrderAddSerializer(many=True)
    mediator_id = serializers.UUIDField()
    delivery_date = serializers.DateField()
    payment_date = serializers.DateField()
    comment = serializers.CharField(required=False)
    discount = serializers.DecimalField(max_digits=15, decimal_places=2, default=0.00, required=False)
    discount_currency = serializers.ChoiceField(
        choices=[("uzs", "uzs"), ("usd", "usd")], required=False
    )
    audit = serializers.ChoiceField(
        choices=[("CHECKED", "tekshirildi"), ("PROCESS", "jarayonda")], required=False
    )
    audit_comment = serializers.CharField(required=False)
    currency = serializers.ChoiceField(choices=[("uzs", "uzs"), ("usd", "usd")])

    def validate(self, data):
        user = User.objects.filter(id=data["mediator_id"]).first()
        if not user:
            raise serializers.ValidationError("User not found")
        data["user"] = user
        return data

    def create(self, validated_data):
        with transaction.atomic():
            resources = validated_data.pop("resources")
            orders = []
            total_price = 0
            for resource in resources:
                orders.append(
                    Order(
                        product=resource["product"],
                        unity=resource["unity"],
                        project_folder=resource.get("project_folder"),
                        project=resource.get("project"),
                        counterparty=resource.get("counterparty"),
                        wherehouse=resource.get("wherehouse"),
                        quantity=resource.get("quantity"),
                        unit_amount=resource.get("unit_amount"),
                        currency=resource.get("currency"),
                        amount=resource.get("amount"),
                        employee=self.context.get("user"),
                        qqs_price=resource.get("qqs_price"),
                        total_price=resource.get("total_price"),
                        qqs=resource.get("qqs"),
                        type="party"
                    )
                )
                if resource.get("currency") == "usd":
                    usd_value = UsdCourse.objects.first().value
                    total_price += resource.get("amount") * usd_value
                else:
                    total_price += resource.get("amount")
            created_orders = Order.objects.bulk_create(orders)
            party = Party.objects.create(
                mediator=validated_data.get("user"),
                delivery_date=validated_data.get("delivery_date"),
                payment_date=validated_data.get("payment_date"),
                comment=validated_data.get("comment"),
                audit=validated_data.get("audit"),
                audit_comment=validated_data.get("audit_comment"),
                discount=validated_data.get("discount"),
                discount_currency=validated_data.get("discount_currency"),
                currency=validated_data.get("currency"),
            )
            party.orders.add(*created_orders)
            party.save()
            PartyAmount.objects.create(
                total_price=Decimal(total_price),
                party=party,
                payment_amount=Decimal(total_price) - Decimal(validated_data.get("discount", 0)),
                cost_amount=Decimal(total_price) - Decimal(validated_data.get("discount", 0)),
            )
            return party


class PartyAmountSerializer(serializers.ModelSerializer):
    class Meta:
        model = PartyAmount
        fields = [
            "id",
            "total_price",
            "cost_amount",
            "calculated_amount",
            "paid_amount",
            "payment_amount",
            "debt_amount",
            "total_expense_amount",
            "overdue_amount"
        ]


class PartyDetailSerializer(serializers.ModelSerializer):
    orders = OrderListSerializer(many=True)
    party_amount = PartyAmountSerializer()
    mediator = serializers.SerializerMethodField(method_name="get_mediator")
    counterparty = serializers.SerializerMethodField(method_name="get_counterparty")

    class Meta:
        model = Party
        fields = [
            "id",
            "number",
            "delivery_date",
            "closed_date",
            "order_date",
            "payment_date",
            "status",
            "payment_status",
            "payment_percentage",
            "process",
            "confirmation",
            "comment",
            "audit",
            "audit_comment",
            "orders",
            "party_amount",
            "mediator",
            "currency",
            "counterparty",
            "discount",
        ]

    def get_mediator(self, obj):
        return {"id": obj.mediator.id, "full_name": obj.mediator.full_name}

    def get_counterparty(self, obj):
        counterparties = obj.orders.values(
            "counterparty__id", "counterparty__name"
        ).distinct()
        counterparties = [
            {"id": c["counterparty__id"], "name": c["counterparty__name"]}
            for c in counterparties
        ]
        return CounterpartySerializer(counterparties, many=True).data


class PartyListSerializer(serializers.ModelSerializer):
    party_amount = PartyAmountSerializer()
    mediator = serializers.SerializerMethodField(method_name="get_mediator")
    counterparty = serializers.SerializerMethodField(method_name="get_counterparty")

    class Meta:
        model = Party
        fields = [
            "id",
            "number",
            "delivery_date",
            "closed_date",
            "order_date",
            "payment_date",
            "status",
            "payment_status",
            "payment_percentage",
            "process",
            "confirmation",
            "comment",
            "audit",
            "audit_comment",
            "party_amount",
            "mediator",
            "counterparty",
            "currency",
            "discount",
        ]

    def get_mediator(self, obj):
        return {"id": obj.mediator.id, "full_name": obj.mediator.full_name}

    def get_counterparty(self, obj):
        counterparties = obj.orders.values(
            "counterparty__id", "counterparty__name"
        ).distinct()
        counterparties = [
            {"id": c["counterparty__id"], "name": c["counterparty__name"]}
            for c in counterparties
        ]
        return CounterpartySerializer(counterparties, many=True).data


class DeletedPartyCreateSerializer(serializers.Serializer):
    comment = serializers.CharField(required=False)

    def validate(self, data):
        party = Party.objects.filter(id=self.context.get("party_id")).first()
        if not party:
            raise serializers.ValidationError("Party not found")
        data["party"] = party
        return data

    def create(self, validated_data):
        with transaction.atomic():
            return DeletedParty.objects.create(
                comment=validated_data.get("comment"), party=validated_data.get("party"),
                user=self.context.get('user')
            )


class DeletedPartyListSerializer(serializers.ModelSerializer):
    party_number = serializers.IntegerField(source="party.number")
    party_total_price = serializers.IntegerField(
        source="party.party_amount.total_price"
    )
    mediator = serializers.SerializerMethodField(method_name="get_mediator")
    party = PartyListSerializer()

    class Meta:
        model = DeletedParty
        fields = [
            "id", 
            "deleted_date", 
            "party_number", 
            "party_total_price", 
            "mediator", 
            'created_at', 
            'comment',
            'party',
            'user',
        ]

    def get_user(self, obj):
        return {
            "id": obj.user.id,
            "full_name": obj.user.full_name,
            "profile_image": obj.user.profile_image.url or None,
        } if obj.user else {}

    def get_mediator(self, obj):
        return {"id": obj.party.mediator.id, "name": obj.party.mediator.full_name}


class PartyOrderUpdateSerializer(serializers.Serializer):
    order_id = serializers.UUIDField()
    product_id = serializers.UUIDField()
    unity_id = serializers.UUIDField()
    project_folder_id = serializers.UUIDField(required=False)
    project_id = serializers.UUIDField(required=False)
    wherehouse_id = serializers.UUIDField()
    counterparty_id = serializers.UUIDField()
    quantity = serializers.IntegerField()
    unit_amount = serializers.DecimalField(max_digits=15, decimal_places=2, default=0.00)
    currency = serializers.ChoiceField(choices=[("uzs", "uzs"), ("usd", "usd")])
    total_price = serializers.DecimalField(max_digits=15, decimal_places=2, default=0.00)

    def validate(self, data):
        order = Order.objects.filter(id=data["order_id"]).first()
        if not order:
            raise serializers.ValidationError("Order not found")
        product = Product.objects.filter(id=data["product_id"]).first()
        if not product:
            raise serializers.ValidationError(f"Product not found on {order.id}")
        unity = Unity.objects.filter(id=data["unity_id"]).first()
        if not unity:
            raise serializers.ValidationError(f"Unity not found on {order.id}")
        if data.get("project_folder_id"):
            project_folder = ProjectFolder.objects.filter(
                id=data["project_folder_id"]
            ).first()
            if not project_folder:
                raise serializers.ValidationError(
                    f"Project Folder not found on {order.id}"
                )
            data["project_folder"] = project_folder
        if data.get("project_id"):
            project = Project.objects.filter(id=data["project_id"]).first()
            if not project:
                raise serializers.ValidationError(f"Project not found on {order.id}")
            data["project"] = project
        wherehouse = WhereHouse.objects.filter(id=data["wherehouse_id"]).first()
        if not wherehouse:
            raise serializers.ValidationError(f"WhereHouse not found on {order.id}")
        counterparty = Counterparty.objects.filter(id=data["counterparty_id"]).first()
        if not counterparty:
            raise serializers.ValidationError(f"Counterparty not found on {order.id}")

        data["order"] = order
        data["product"] = product
        data["unity"] = unity
        data["wherehouse"] = wherehouse
        data["counterparty"] = counterparty
        return data


class PartyUpdateSerializer(serializers.ModelSerializer):
    orders = PartyOrderUpdateSerializer(many=True, required=False)

    class Meta:
        model = Party
        fields = [
            "mediator",
            "delivery_date",
            "payment_date",
            "orders",
            "comment",
            "audit",
            "audit_comment",
            "discount",
            "discount_currency",
        ]
        extra_kwargs = {
            "mediator": {"required": False},
            "delivery_date": {"required": False},
            "payment_date": {"required": False},
            "comment": {"required": False},
            "audit": {"required": False},
            "audit_comment": {"required": False},
            "discount": {"required": False},
            "discount_currency": {"required": False},
        }

    def update(self, instance, validated_data):
        total_price = 0
        orders_data = validated_data.pop("orders")
        update_orders = []
        with transaction.atomic():
            instance.mediator = validated_data.get("mediator", instance.mediator)
            instance.delivery_date = validated_data.get(
                "delivery_date", instance.delivery_date
            )
            instance.payment_date = validated_data.get(
                "payment_date", instance.payment_date
            )
            instance.save()

            for order_data in orders_data:
                order = order_data["order"]
                order.product = order_data["product"]
                order.unity = order_data["unity"]
                order.wherehouse = order_data["wherehouse"]
                order.counterparty = order_data["counterparty"]
                order.quantity = order_data["quantity"]
                order.currency = order_data["currency"]
                order.unit_amount = order_data["unit_amount"]
                order.total_price = order_data["total_price"]
                total_price += order.total_price
                if "project_folder" in order_data:
                    order.project_folder = order_data["project_folder"]
                if "project" in order_data:
                    order.project = order_data["project"]

                update_orders.append(order)

            Order.objects.bulk_update(
                update_orders,
                fields=[
                    "product",
                    "unity",
                    "wherehouse",
                    "counterparty",
                    "quantity",
                    "unit_amount",
                    "currency",
                    "total_price",
                    "project_folder",
                    "project",
                ],
            )
            party_amount = PartyAmount.objects.get(party=instance)
            party_amount.total_price = total_price
            party_amount.cost_amount = (
                total_price - instance.discount if instance.discount else 0.00
            )
            party_amount.payment_amount = (
                total_price - instance.discount if instance.discount else 0.00
            )
            party_amount.save()
            return instance


class PartyExpenceCreateSerializer(serializers.ModelSerializer):
    class Meta:
        model = Expence
        fields = [
            "cash_transaction",
            "payment_type",
            "project_folder",
            "project",
            "counterparty",
            "price",
            "exchange_rate",
            "currency",
            "date",
            "comment",
            "party",
        ]

    def validate(self, data):
        price = data.get('price')
        exchange_rate = data.get('exchange_rate')
        party = data.get('party')
        currency = data.get('currency', 'uzs').lower()
        
        if price and price < 0:
            raise serializers.ValidationError("Narxi manfiy bo'lishi mumkin emas")
        
        if exchange_rate and exchange_rate < 0:
            raise serializers.ValidationError("Kurs manfiy bo'lishi mumkin emas")
        
        if not party:
            raise serializers.ValidationError("Party talab qilinadi")
        
        try:
            usd_course = UsdCourse.objects.first()
            if not usd_course or not usd_course.value:
                raise serializers.ValidationError("USD kursi topilmadi")
        except UsdCourse.DoesNotExist:
            raise serializers.ValidationError("USD kursi topilmadi")
        
        return data

    def create(self, validated_data):
        with transaction.atomic():
            usd_course = UsdCourse.objects.first()
            if not usd_course:
                raise serializers.ValidationError("USD kursi topilmadi")
            
            usd_value = usd_course.value
            
            exchange_rate = validated_data.get("exchange_rate") or 1
            final_price = validated_data.get("price")
            currency = validated_data.get("currency", "uzs").lower()
            
            expence = Expence.objects.create(
                cash_transaction=validated_data.get("cash_transaction"),
                payment_type=validated_data.get("payment_type"),
                project_folder=validated_data.get("project_folder"),
                project=validated_data.get("project"),
                counterparty=validated_data.get("counterparty"),
                price=final_price,
                exchange_rate=exchange_rate,
                currency=currency,
                date=validated_data.get("date"),
                comment=validated_data.get("comment"),
                party=validated_data.get("party"),
                user=self.context.get('user'),
            )
            
            cash_transaction = expence.cash_transaction
            payment_type = expence.payment_type
            party = expence.party
            
            if currency == "uzs":
                cash_transaction.expence_balance_uzs += expence.price
                cash_transaction.total_balance_uzs = (
                    cash_transaction.income_balance_uzs
                    - cash_transaction.expence_balance_uzs
                )
                
                if payment_type.total_uzs > expence.price:
                    payment_type.total_uzs -= expence.price
                
                if expence.counterparty:
                    if expence.counterparty.kredit_uzs > 0:
                        expence.counterparty.kredit_uzs -= expence.price
                        expence.counterparty.total_kredit -= expence.price
                        
                        expence.counterparty.debit_uzs += expence.price
                        expence.counterparty.total_debit += expence.price
                    else:
                        expence.counterparty.debit_uzs += expence.price
                        expence.counterparty.total_debit += expence.price
                    
                    expence.counterparty.save()
                
                if party:
                    if party.currency == "uzs":
                        party.party_amount.payment_amount -= expence.price
                        party.party_amount.paid_amount += expence.price
                        party.party_amount.save()
                    elif party.currency == 'usd':
                        converted_price = round(expence.price / usd_value)
                        party.party_amount.payment_amount -= converted_price
                        party.party_amount.paid_amount += converted_price
                        party.party_amount.save()
                    
                    party.save()
            
            elif currency == "usd":
                cash_transaction.expence_balance_usd += expence.price
                cash_transaction.total_balance_usd = (
                    cash_transaction.income_balance_usd
                    - cash_transaction.expence_balance_usd
                )
                
                if payment_type.total_usd > expence.price:
                    payment_type.total_usd -= expence.price
                
                if expence.counterparty:
                    if expence.counterparty.kredit_usd > 0:
                        expence.counterparty.kredit_usd -= expence.price
                        expence.counterparty.total_kredit -= expence.price
                        
                        expence.counterparty.debit_usd += expence.price
                        expence.counterparty.total_debit += expence.price
                    else:
                        expence.counterparty.debit_usd += expence.price
                        expence.counterparty.total_debit += expence.price
                    
                    expence.counterparty.save()
                
                if party:
                    if party.currency == "usd":
                        party.party_amount.payment_amount -= expence.price
                        party.party_amount.paid_amount += expence.price
                        party.party_amount.save()
                    elif party.currency == "uzs":
                        converted_price = expence.price * usd_value
                        party.party_amount.payment_amount -= converted_price
                        party.party_amount.paid_amount += converted_price
                        party.party_amount.save()
                    
                    party.save()
            
            cash_transaction.save()
            payment_type.save()
            
            return expence


class ReceivePartySerializer(serializers.Serializer):
    order_id = serializers.UUIDField()
    product_quantity = serializers.IntegerField()
    product_receive_date = serializers.DateField()


class ReceiveMultipleOrderSerializer(serializers.Serializer):
    product = ReceivePartySerializer(many=True)