from django.contrib import admin
from django import forms
from django.core.exceptions import ValidationError
from django.utils import timezone
from rest_framework_api_key.admin import APIKeyModelAdmin
from rest_framework_api_key.models import APIKey

from .models import AuditLog, AllInOneSpecification, ChoiceValue, ComputerSpecification, DesktopSpecification, Device, DeviceTask, Employee, FieldDefinition, FieldOption, ImportJob, InspectionRecord, InventoryAPIKey, LaptopSpecification, MonitorSpecification, PrinterSpecification, RepairRecord, SavedView, UserPreference, UserProfile, WorkflowEvent
from .permissions import can_edit


try:
    admin.site.unregister(APIKey)
except admin.sites.NotRegistered:
    pass


class InventoryAPIKeyAdminForm(forms.ModelForm):
    class Meta:
        model = InventoryAPIKey
        fields = "__all__"

    def clean_expiry_date(self):
        expiry = self.cleaned_data.get("expiry_date")
        if not expiry:
            raise ValidationError("Ein Ablaufdatum ist aus Sicherheitsgründen erforderlich.")
        if expiry <= timezone.now():
            raise ValidationError("Das Ablaufdatum muss in der Zukunft liegen.")
        return expiry

    def clean(self):
        cleaned = super().clean()
        user = cleaned.get("service_user")
        if cleaned.get("can_write") and user and not can_edit(user):
            self.add_error("service_user", "Schreibzugriff erfordert ein Bearbeiter- oder Administratorkonto.")
        return cleaned


@admin.register(Device)
class DeviceAdmin(admin.ModelAdmin):
    list_display = ("number", "stage", "status", "device_type", "model", "employee", "date", "archived_at")
    search_fields = ("=number", "model", "laptop_specification__cpu", "desktop_specification__cpu", "aio_specification__cpu", "computer_specification__cpu", "ticket", "comment")
    list_filter = ("stage", "status", "device_type", "employee", "archived_at")
    readonly_fields = ("number", "created_at", "updated_at")


@admin.register(DeviceTask)
class DeviceTaskAdmin(admin.ModelAdmin):
    list_display = ("title", "device", "state", "assigned_to", "due_date", "completed_at")
    list_filter = ("state", "due_date")
    search_fields = ("title", "device__number")


@admin.register(WorkflowEvent)
class WorkflowEventAdmin(admin.ModelAdmin):
    list_display = ("device", "from_stage", "to_stage", "user", "created_at")
    readonly_fields = ("device", "from_stage", "to_stage", "note", "user", "created_at")


@admin.register(InspectionRecord, RepairRecord)
class StageRecordAdmin(admin.ModelAdmin):
    list_display = ("device", "recorded_by", "created_at")

    def get_readonly_fields(self, request, obj=None):
        return tuple(field.name for field in self.model._meta.fields)

    def has_add_permission(self, request):
        return False

    def has_delete_permission(self, request, obj=None):
        return False


@admin.register(LaptopSpecification, DesktopSpecification, AllInOneSpecification, ComputerSpecification, MonitorSpecification, PrinterSpecification)
class SpecificationAdmin(admin.ModelAdmin):
    list_display = ("device",)

    def has_add_permission(self, request):
        return False

    def has_change_permission(self, request, obj=None):
        return False

    def has_delete_permission(self, request, obj=None):
        return False


@admin.register(ChoiceValue)
class ChoiceValueAdmin(admin.ModelAdmin):
    list_display = ("kind", "label", "active", "sort_order")
    list_filter = ("kind", "active")


@admin.register(InventoryAPIKey)
class InventoryAPIKeyAdmin(APIKeyModelAdmin):
    form = InventoryAPIKeyAdminForm
    list_display = (
        "prefix", "name", "service_user", "can_read", "can_write", "created",
        "expiry_date", "_has_expired", "revoked", "last_used_at",
    )
    list_filter = ("can_read", "can_write", "revoked", "created")
    search_fields = ("name", "prefix", "service_user__username")

    def get_readonly_fields(self, request, obj=None):
        return super().get_readonly_fields(request, obj) + ("created_by", "last_used_at", "last_used_ip")

    def save_model(self, request, obj, form=None, change=False):
        if not obj.pk:
            obj.created_by = request.user
        super().save_model(request, obj, form, change)


admin.site.register(Employee)
admin.site.register(UserProfile)
admin.site.register(FieldDefinition)
admin.site.register(FieldOption)
admin.site.register(AuditLog)
admin.site.register(UserPreference)
admin.site.register(SavedView)
admin.site.register(ImportJob)