from rest_framework import serializers
from .models import LocationStatistics, LocationGroupStatistics

class LocationStatisticsSerializer(serializers.ModelSerializer):
    """货位统计序列化器"""
    
    warehouse_display = serializers.CharField(source='warehouse_name', read_only=True)
    layer_display = serializers.SerializerMethodField()
    t5_group_count = serializers.SerializerMethodField()
    t4_group_count = serializers.SerializerMethodField()
    s4_group_count = serializers.SerializerMethodField()
    t2_group_count = serializers.SerializerMethodField()
    t1_group_count = serializers.SerializerMethodField()
    t5_used_group_count = serializers.SerializerMethodField()
    t4_used_group_count = serializers.SerializerMethodField()
    s4_used_group_count = serializers.SerializerMethodField()
    t2_used_group_count = serializers.SerializerMethodField()
    t1_used_group_count = serializers.SerializerMethodField()
    t5_available_group_count = serializers.SerializerMethodField()
    t4_available_group_count = serializers.SerializerMethodField()
    s4_available_group_count = serializers.SerializerMethodField()
    t2_available_group_count = serializers.SerializerMethodField()
    t1_available_group_count = serializers.SerializerMethodField()
    
    class Meta:
        model = LocationStatistics
        fields = [
            'id', 'warehouse_code', 'warehouse_name', 'warehouse_display', 'layer', 'layer_display',
            't5_total', 't5_used', 't5_available',
            't5_group_count', 't5_used_group_count', 't5_available_group_count',
            't4_total', 't4_used', 't4_available',
            't4_group_count', 't4_used_group_count', 't4_available_group_count',
            's4_total', 's4_used', 's4_available',
            's4_group_count', 's4_used_group_count', 's4_available_group_count',
            't2_total', 't2_used', 't2_available',
            't2_group_count', 't2_used_group_count', 't2_available_group_count',
            't1_total', 't1_used', 't1_available',
            't1_group_count', 't1_used_group_count', 't1_available_group_count',
            'total_locations', 'total_used', 'total_available', 'utilization_rate',
            'statistic_time', 'is_latest'
        ]
    
    def get_layer_display(self, obj):
        return f"{obj.layer}层"

    def get_t5_group_count(self, obj):
        return self._get_type_group_count(obj, 'T5')

    def get_t5_used_group_count(self, obj):
        return self._get_type_group_count(obj, 'T5', 'used')

    def get_t5_available_group_count(self, obj):
        return self._get_type_group_count(obj, 'T5', 'available')

    def get_t4_group_count(self, obj):
        return self._get_type_group_count(obj, 'T4')

    def get_t4_used_group_count(self, obj):
        return self._get_type_group_count(obj, 'T4', 'used')

    def get_t4_available_group_count(self, obj):
        return self._get_type_group_count(obj, 'T4', 'available')

    def get_s4_group_count(self, obj):
        return self._get_type_group_count(obj, 'S4')

    def get_s4_used_group_count(self, obj):
        return self._get_type_group_count(obj, 'S4', 'used')

    def get_s4_available_group_count(self, obj):
        return self._get_type_group_count(obj, 'S4', 'available')

    def get_t2_group_count(self, obj):
        return self._get_type_group_count(obj, 'T2')

    def get_t2_used_group_count(self, obj):
        return self._get_type_group_count(obj, 'T2', 'used')

    def get_t2_available_group_count(self, obj):
        return self._get_type_group_count(obj, 'T2', 'available')

    def get_t1_group_count(self, obj):
        return self._get_type_group_count(obj, 'T1')

    def get_t1_used_group_count(self, obj):
        return self._get_type_group_count(obj, 'T1', 'used')

    def get_t1_available_group_count(self, obj):
        return self._get_type_group_count(obj, 'T1', 'available')

    def _get_group_stats(self, obj):
        if not hasattr(self, '_group_stats_cache'):
            self._group_stats_cache = {}

        key = (obj.warehouse_code, obj.layer, obj.statistic_time)
        if key not in self._group_stats_cache:
            self._group_stats_cache[key] = list(
                LocationGroupStatistics.objects.filter(
                    warehouse_code=obj.warehouse_code,
                    layer=obj.layer,
                    statistic_time=obj.statistic_time
                )
            )

        return self._group_stats_cache[key]

    def _get_type_group_count(self, obj, type_code, usage=None):
        group_stats = self._get_group_stats(obj)
        count = 0
        for stat in group_stats:
            breakdown = stat.location_type_breakdown or {}
            type_info = breakdown.get(type_code, {})
            if usage == 'used':
                if type_info.get('used', 0) > 0:
                    count += 1
            elif usage == 'available':
                if type_info.get('available', 0) > 0:
                    count += 1
            else:
                if type_info.get('total', 0) > 0:
                    count += 1
        return count

class LocationGroupStatisticsSerializer(serializers.ModelSerializer):
    """货位组统计序列化器"""
    
    warehouse_display = serializers.CharField(source='warehouse_name', read_only=True)
    layer_display = serializers.SerializerMethodField()
    
    class Meta:
        model = LocationGroupStatistics
        fields = [
            'id', 'warehouse_code', 'warehouse_name', 'warehouse_display',
            'layer', 'layer_display', 'location_group',
            'total_locations', 'used_locations', 'available_locations', 'utilization_rate',
            'location_type_breakdown', 'statistic_time'
        ]
        ordering = ['warehouse_code', 'layer', 'total_locations']
    
    def get_layer_display(self, obj):
        return f"{obj.layer}层"