import datetime

from django.utils import timezone
from rest_framework import serializers, status, permissions
from rest_framework.response import Response
from rest_framework.views import APIView

from printing import models as printing_models
from api_man.serializers import ProductSerializer


class PrintingJobV2Serializer(serializers.ModelSerializer):
    """v2 独立的印染任务序列化器，包含开单数量"""

    billed_quantity = serializers.DecimalField(max_digits=18, decimal_places=2, read_only=True)
    business_object_id = serializers.SerializerMethodField()
    width = serializers.SerializerMethodField()
    fabric = serializers.SerializerMethodField()
    product = ProductSerializer(read_only=True)

    class Meta:
        model = printing_models.PrintingJob
        fields = [
            'id',
            'printing_order',
            'product',
            'work_state',
            'quantity',
            'width',
            'fabric',
            'unit',
            'size',
            'pieces',
            'description',
            'business_object_id',
            'created_at',
            'updated_at',
            'billed_quantity',
        ]
        read_only_fields = ['id', 'created_at', 'updated_at', 'billed_quantity']

    def get_business_object_id(self, obj):
        return obj.business_object_id

    def get_width(self, obj: printing_models.PrintingJob) -> float:
        return obj.printing_order.width

    def get_fabric(self, obj: printing_models.PrintingJob) -> str:
        return obj.printing_order.fabric


class PrintingJobByCustomerView(APIView):
    """
    按客户与日期范围查询印染任务。

    必填 query 参数:
    - customer_id: 客户 ID
    - date_from: 开始日期 (YYYY-MM-DD)
    - date_to: 结束日期 (YYYY-MM-DD)，闭区间，包含 23:59:59
    可选过滤：
    - printing_order: 按印染主订单 ID
    - product_id / product_name / product_human_id / product_width_size / product_color
    """

    serializer_class = PrintingJobV2Serializer
    permission_classes = [permissions.AllowAny]

    def get(self, request):
        qp = request.query_params
        customer_id = qp.get('customer_id')
        date_from = qp.get('date_from')
        date_to = qp.get('date_to')
        printing_order_id = qp.get('printing_order')
        product_id = qp.get('product_id')
        product_name = qp.get('product_name')
        product_human_id = qp.get('product_human_id')
        product_width_size = qp.get('product_width_size')
        product_color = qp.get('product_color')

        if not customer_id:
            return Response({'detail': 'customer_id 为必填参数'}, status=status.HTTP_400_BAD_REQUEST)
        if not date_from or not date_to:
            return Response({'detail': 'date_from 与 date_to 为必填参数'}, status=status.HTTP_400_BAD_REQUEST)

        try:
            customer_id_int = int(customer_id)
        except (TypeError, ValueError):
            return Response({'detail': 'customer_id 必须为数字'}, status=status.HTTP_400_BAD_REQUEST)

        try:
            start_date = datetime.datetime.strptime(date_from, '%Y-%m-%d').date()
            end_date = datetime.datetime.strptime(date_to, '%Y-%m-%d').date()
        except ValueError:
            return Response({'detail': '日期格式需为 YYYY-MM-DD'}, status=status.HTTP_400_BAD_REQUEST)

        # 闭区间：包含当日 00:00:00 和 23:59:59.999999
        start_dt = datetime.datetime.combine(start_date, datetime.time.min)
        end_dt = datetime.datetime.combine(end_date, datetime.time.max)

        if timezone.is_naive(start_dt):
            start_dt = timezone.make_aware(start_dt, timezone.get_default_timezone())
        if timezone.is_naive(end_dt):
            end_dt = timezone.make_aware(end_dt, timezone.get_default_timezone())

        queryset = printing_models.PrintingJob.objects.select_related('printing_order', 'product').filter(
            printing_order__customer_id=customer_id_int,
            created_at__gte=start_dt,
            created_at__lte=end_dt,
        )

        # 可选过滤：printing_order
        if printing_order_id:
            try:
                queryset = queryset.filter(printing_order_id=int(printing_order_id))
            except (TypeError, ValueError):
                return Response({'detail': 'printing_order 必须为数字'}, status=status.HTTP_400_BAD_REQUEST)

        # 可选过滤：product
        if product_id:
            try:
                queryset = queryset.filter(product_id=int(product_id))
            except (TypeError, ValueError):
                return Response({'detail': 'product_id 必须为数字'}, status=status.HTTP_400_BAD_REQUEST)
        if product_name:
            queryset = queryset.filter(product__name__icontains=product_name)
        if product_human_id:
            queryset = queryset.filter(product__human_id__icontains=product_human_id)
        if product_width_size:
            try:
                width_decimal = float(product_width_size)
            except (TypeError, ValueError):
                return Response({'detail': 'product_width_size 必须为数字'}, status=status.HTTP_400_BAD_REQUEST)
            queryset = queryset.filter(product__width_size=width_decimal)
        if product_color:
            queryset = queryset.filter(product__color__icontains=product_color)

        queryset = queryset.order_by('-created_at')

        serializer = self.serializer_class(queryset, many=True)
        return Response(serializer.data)