"""
Тесты для Budget - reserved_amount, my_department, stats endpoints.
"""

from decimal import Decimal

import pytest
from django.contrib.auth.models import Permission
from django.utils import timezone
from rest_framework import status

from procurement.constants import ProcurementStatus, UrgencyLevel
from procurement.models import (
    Budget,
    ProcurementItem,
    ProcurementRequest,
)


@pytest.mark.django_db
class TestBudgetReservedAmount:
    """Тесты для reserved_amount и available_amount."""

    @pytest.fixture(autouse=True)
    def setup(self, department_factory, user_factory, link_factory):
        """Настройка тестовых данных."""
        self.department = department_factory(name="IT Reserved Test")
        now = timezone.now()
        self.quarter = (now.month - 1) // 3 + 1

        self.budget = Budget.objects.create(
            department=self.department,
            year=now.year,
            quarter=self.quarter,
            allocated_amount=Decimal("100000.00"),
            spent_amount=Decimal("20000.00"),
        )

        self.user = user_factory(
            email="budgetuser@test.com",
            first_name="Test",
            last_name="User",
        )
        link_factory(self.user, self.department, is_active=True)

    def test_reserved_amount_no_pending(self):
        """Тест: reserved_amount = 0 если нет pending заявок."""
        assert self.budget.reserved_amount == Decimal("0.00")

    def test_reserved_amount_with_pending(self):
        """Тест: reserved_amount считает сумму pending заявок."""
        # Создаём pending заявки с позициями
        request1 = ProcurementRequest.objects.create(
            title="Заявка 1",
            description="Описание",
            department=self.department,
            requestor=self.user,
            status=ProcurementStatus.PENDING,
            urgency=UrgencyLevel.LOW,
        )
        ProcurementItem.objects.create(
            request=request1,
            name="Товар 1",
            quantity=1,
            unit="шт",
            estimated_unit_price=Decimal("5000.00"),
        )

        request2 = ProcurementRequest.objects.create(
            title="Заявка 2",
            description="Описание",
            department=self.department,
            requestor=self.user,
            status=ProcurementStatus.PENDING,
            urgency=UrgencyLevel.MEDIUM,
        )
        ProcurementItem.objects.create(
            request=request2,
            name="Товар 2",
            quantity=1,
            unit="шт",
            estimated_unit_price=Decimal("3000.00"),
        )

        # reserved должен быть 8000
        assert self.budget.reserved_amount == Decimal("8000.00")

    def test_available_amount(self):
        """Тест: available_amount = remaining - reserved."""
        request = ProcurementRequest.objects.create(
            title="Pending заявка",
            description="Описание",
            department=self.department,
            requestor=self.user,
            status=ProcurementStatus.PENDING,
            urgency=UrgencyLevel.LOW,
        )
        ProcurementItem.objects.create(
            request=request,
            name="Товар",
            quantity=1,
            unit="шт",
            estimated_unit_price=Decimal("10000.00"),
        )

        # remaining = 100000 - 20000 = 80000
        # reserved = 10000
        # available = 80000 - 10000 = 70000
        assert self.budget.remaining_amount == Decimal("80000.00")
        assert self.budget.reserved_amount == Decimal("10000.00")
        assert self.budget.available_amount == Decimal("70000.00")


@pytest.mark.django_db
class TestBudgetMyDepartmentEndpoint:
    """Тесты для /budgets/my-department/ endpoint."""

    @pytest.fixture(autouse=True)
    def setup(self, api_client, department_factory, user_factory, link_factory):
        """Настройка тестовых данных."""
        self.client = api_client

        self.department = department_factory(name="IT My Dept Test")

        now = timezone.now()
        self.quarter = (now.month - 1) // 3 + 1

        self.budget = Budget.objects.create(
            department=self.department,
            year=now.year,
            quarter=self.quarter,
            allocated_amount=Decimal("100000.00"),
            spent_amount=Decimal("30000.00"),
        )

        self.user = user_factory(
            email="mydeptuser@test.com",
            first_name="Test",
            last_name="User",
        )
        link_factory(self.user, self.department, is_active=True)
        self.user_factory = user_factory

    def test_my_department_success(self):
        """Тест: получение бюджета своего отдела."""
        self.client.force_authenticate(user=self.user)

        response = self.client.get("/api/v1/procurement/budgets/my-department/")

        assert response.status_code == status.HTTP_200_OK
        assert response.data["department"] == self.department.id
        allocated = Decimal(response.data["allocated_amount"])
        assert allocated == Decimal("100000.00")
        spent = Decimal(response.data["spent_amount"])
        assert spent == Decimal("30000.00")
        remaining = Decimal(response.data["remaining_amount"])
        assert remaining == Decimal("70000.00")
        assert "reserved_amount" in response.data
        assert "available_amount" in response.data

    def test_my_department_no_department(self):
        """Тест: 404 если пользователь не в отделе."""
        user_no_dept = self.user_factory(
            email="nodept@test.com",
            first_name="No",
            last_name="Dept",
        )
        self.client.force_authenticate(user=user_no_dept)

        response = self.client.get("/api/v1/procurement/budgets/my-department/")

        assert response.status_code == status.HTTP_404_NOT_FOUND

    def test_my_department_no_budget(self):
        """Тест: 404 если нет бюджета на текущий квартал."""
        # Удаляем бюджет
        self.budget.delete()

        self.client.force_authenticate(user=self.user)

        response = self.client.get("/api/v1/procurement/budgets/my-department/")

        assert response.status_code == status.HTTP_404_NOT_FOUND


@pytest.mark.django_db
class TestProcurementStatsEndpoints:
    """Тесты для /stats/ endpoints."""

    @pytest.fixture(autouse=True)
    def setup(self, api_client, department_factory, user_factory, link_factory):
        """Настройка тестовых данных."""
        self.client = api_client

        self.department = department_factory(name="IT Stats Test")

        self.user = user_factory(
            email="statsuser@test.com",
            first_name="Test",
            last_name="User",
        )
        link_factory(self.user, self.department, is_active=True)

        self.staff_user = user_factory(
            email="statsstaff@test.com",
            first_name="Staff",
            last_name="User",
        )
        self.staff_user.is_staff = True
        self.staff_user.save()

        # Создаём несколько заявок
        for i in range(3):
            ProcurementRequest.objects.create(
                title=f"Заявка {i + 1}",
                description="Описание",
                department=self.department,
                requestor=self.user,
                status=ProcurementStatus.PENDING,
                urgency=UrgencyLevel.MEDIUM,
            )

    def test_stats_overview(self):
        """Тест: получение общей статистики."""
        self.client.force_authenticate(user=self.user)

        response = self.client.get("/api/v1/procurement/stats/overview/")

        assert response.status_code == status.HTTP_200_OK
        assert "total_requests" in response.data
        assert "pending_requests" in response.data
        assert "by_status" in response.data
        assert "by_urgency" in response.data

    def test_stats_by_department_staff(self):
        """Тест: статистика по отделам для staff."""
        self.client.force_authenticate(user=self.staff_user)

        response = self.client.get("/api/v1/procurement/stats/by-department/")

        assert response.status_code == status.HTTP_200_OK
        assert isinstance(response.data, list)

    def test_stats_by_department_regular_user(self):
        """Тест: 403 для обычного пользователя."""
        self.client.force_authenticate(user=self.user)

        response = self.client.get("/api/v1/procurement/stats/by-department/")

        assert response.status_code == status.HTTP_403_FORBIDDEN

    def test_stats_by_department_head(self):
        """Тест: руководитель отдела видит статистику своих отделов."""
        # Делаем пользователя руководителем
        self.department.head = self.user
        self.department.save()

        self.client.force_authenticate(user=self.user)

        response = self.client.get("/api/v1/procurement/stats/by-department/")

        assert response.status_code == status.HTTP_200_OK
        assert len(response.data) == 1
        assert response.data[0]["department"]["id"] == self.department.id


@pytest.mark.django_db
class TestBudgetAlerts:
    """Тесты для алертов бюджета."""

    @pytest.fixture(autouse=True)
    def setup(self, api_client, department_factory, user_factory, link_factory):
        """Настройка тестовых данных."""
        self.client = api_client

        self.department = department_factory(name="IT Alerts Test")

        now = timezone.now()
        self.quarter = (now.month - 1) // 3 + 1

        # Бюджет почти исчерпан (95% использовано)
        self.budget = Budget.objects.create(
            department=self.department,
            year=now.year,
            quarter=self.quarter,
            allocated_amount=Decimal("100000.00"),
            spent_amount=Decimal("95000.00"),  # 95% использовано
        )

        self.requestor = user_factory(
            email="alertsrequestor@test.com",
            first_name="Requestor",
            last_name="User",
        )
        link_factory(self.requestor, self.department, is_active=True)

        # Руководитель отдела
        self.dept_head = user_factory(
            email="alertshead@test.com",
            first_name="Department",
            last_name="Head",
        )
        link_factory(self.dept_head, self.department, is_active=True)
        self.department.head = self.dept_head
        self.department.save()

        # Даём права на approve
        perm = Permission.objects.get(codename="approve_procurementrequest")
        self.dept_head.user_permissions.add(perm)

    def test_budget_utilization_above_90(self):
        """Тест: бюджет используется более чем на 90%."""
        assert self.budget.utilization_percentage == Decimal("95.00")
        assert self.budget.remaining_amount == Decimal("5000.00")