import pytest
from fastapi import status


class TestItemCRUD:
    """Test item creation, read, update, delete."""

    def test_create_item(self, test_client, test_db):
        """Test creating an inventory item."""
        response = test_client.post(
            "/api/items",
            json={
                "name": "Test Item",
                "category": "Electronics",
                "item_type": "Component",
                "quantity": 10,
                "barcode": "123456789",
                "part_number": "PN-12345"
            }
        )
        assert response.status_code == status.HTTP_201_CREATED
        data = response.json()
        assert data["name"] == "Test Item"
        assert data["quantity"] == 10

    def test_create_item_missing_required_field(self, test_client):
        """Test that missing required fields fail."""
        response = test_client.post(
            "/api/items",
            json={"name": "Test Item"}
        )
        assert response.status_code == status.HTTP_422_UNPROCESSABLE_ENTITY

    def test_get_item_by_id(self, test_client, test_db):
        """Test retrieving an item by ID."""
        from backend.models import Item

        item = Item(
            name="Test Item",
            category="Electronics",
            item_type="Component",
            quantity=10,
            barcode="123456789",
            part_number="PN-12345"
        )
        test_db.add(item)
        test_db.commit()

        response = test_client.get(f"/api/items/{item.id}")
        assert response.status_code == status.HTTP_200_OK
        data = response.json()
        assert data["name"] == "Test Item"
        assert data["barcode"] == "123456789"

    def test_list_items(self, test_client, test_db):
        """Test listing all items."""
        from backend.models import Item

        item1 = Item(name="Item1", category="A", item_type="Type", quantity=5, barcode="111", part_number="PN1")
        item2 = Item(name="Item2", category="B", item_type="Type", quantity=3, barcode="222", part_number="PN2")
        test_db.add_all([item1, item2])
        test_db.commit()

        response = test_client.get("/api/items")
        assert response.status_code == status.HTTP_200_OK
        data = response.json()
        assert len(data) >= 2

    def test_update_item(self, test_client, test_db):
        """Test updating an item."""
        from backend.models import Item

        item = Item(
            name="Test Item",
            category="Electronics",
            item_type="Component",
            quantity=10,
            barcode="123456789",
            part_number="PN-12345"
        )
        test_db.add(item)
        test_db.commit()

        response = test_client.put(
            f"/api/items/{item.id}",
            json={"quantity": 20, "part_number": "PN-99999"}
        )
        assert response.status_code == status.HTTP_200_OK
        data = response.json()
        assert data["quantity"] == 20
        assert data["part_number"] == "PN-99999"

    def test_delete_item_admin_only(self, test_client, test_db, admin_token):
        """Test deleting an item (admin only)."""
        from backend.models import Item

        item = Item(
            name="Test Item",
            category="Electronics",
            item_type="Component",
            quantity=10,
            barcode="123456789",
            part_number="PN-12345"
        )
        test_db.add(item)
        test_db.commit()
        item_id = item.id

        response = test_client.delete(
            f"/api/items/{item_id}",
            headers={"Authorization": f"Bearer {admin_token}"}
        )
        assert response.status_code == status.HTTP_204_NO_CONTENT

        # Verify audit log persists
        response = test_client.get(f"/api/audit-logs?item_id={item_id}")
        assert response.status_code == status.HTTP_200_OK


class TestItemValidation:
    """Test item field validation."""

    def test_barcode_unique(self, test_client, test_db):
        """Test that barcodes must be unique."""
        from backend.models import Item

        item1 = Item(
            name="Item1",
            category="A",
            item_type="Type",
            quantity=5,
            barcode="UNIQUE123",
            part_number="PN1"
        )
        test_db.add(item1)
        test_db.commit()

        # Try to create duplicate barcode
        response = test_client.post(
            "/api/items",
            json={
                "name": "Item2",
                "category": "B",
                "item_type": "Type",
                "quantity": 5,
                "barcode": "UNIQUE123",
                "part_number": "PN2"
            }
        )
        assert response.status_code == status.HTTP_409_CONFLICT

    def test_quantity_non_negative(self, test_client):
        """Test that quantity must be non-negative."""
        response = test_client.post(
            "/api/items",
            json={
                "name": "Test",
                "category": "A",
                "item_type": "Type",
                "quantity": -5,
                "barcode": "123",
                "part_number": "PN"
            }
        )
        assert response.status_code == status.HTTP_422_UNPROCESSABLE_ENTITY