# -*- coding: utf-8 -*-
from __future__ import unicode_literals

from datetime import datetime, timedelta

from django.urls import reverse

from part.models import Part
from build.models import Build, BuildItem
from stock.models import StockItem

from InvenTree.status_codes import BuildStatus
from InvenTree.api_tester import InvenTreeAPITestCase


class BuildAPITest(InvenTreeAPITestCase):
    """
    Series of tests for the Build DRF API
    """

    fixtures = [
        'category',
        'part',
        'location',
        'bom',
        'build',
        'stock',
    ]

    # Required roles to access Build API endpoints
    roles = [
        'build.change',
        'build.add'
    ]

    def setUp(self):

        super().setUp()


class BuildCompleteTest(BuildAPITest):
    """
    Unit testing for the build complete API endpoint
    """

    def setUp(self):

        super().setUp()

        self.build = Build.objects.get(pk=1)

        self.url = reverse('api-build-output-complete', kwargs={'pk': self.build.pk})

    def test_invalid(self):
        """
        Test with invalid data
        """

        # Test with an invalid build ID
        self.post(
            reverse('api-build-output-complete', kwargs={'pk': 99999}),
            {},
            expected_code=400
        )

        data = self.post(self.url, {}, expected_code=400).data

        self.assertIn("This field is required", str(data['outputs']))
        self.assertIn("This field is required", str(data['location']))

        # Test with an invalid location
        data = self.post(
            self.url,
            {
                "outputs": [],
                "location": 999999,
            },
            expected_code=400
        ).data

        self.assertIn(
            "Invalid pk",
            str(data["location"])
        )

        data = self.post(
            self.url,
            {
                "outputs": [],
                "location": 1,
            },
            expected_code=400
        ).data

        self.assertIn("A list of build outputs must be provided", str(data))

        stock_item = StockItem.objects.create(
            part=self.build.part,
            quantity=100,
        )

        post_data = {
            "outputs": [
                {
                    "output": stock_item.pk,
                },
            ],
            "location": 1,
        }

        # Post with a stock item that does not match the build
        data = self.post(
            self.url,
            post_data,
            expected_code=400
        ).data

        self.assertIn(
            "Build output does not match the parent build",
            str(data["outputs"][0])
        )

        # Now, ensure that the stock item *does* match the build
        stock_item.build = self.build
        stock_item.save()

        data = self.post(
            self.url,
            post_data,
            expected_code=400,
        ).data

        self.assertIn(
            "This build output has already been completed",
            str(data["outputs"][0]["output"])
        )

    def test_complete(self):
        """
        Test build order completion
        """

        # We start without any outputs assigned against the build
        self.assertEqual(self.build.incomplete_outputs.count(), 0)

        # Create some more build outputs
        for ii in range(10):
            self.build.create_build_output(10)

        # Check that we are in a known state
        self.assertEqual(self.build.incomplete_outputs.count(), 10)
        self.assertEqual(self.build.incomplete_count, 100)
        self.assertEqual(self.build.completed, 0)

        # We shall complete 4 of these outputs
        outputs = self.build.incomplete_outputs[0:4]

        self.post(
            self.url,
            {
                "outputs": [{"output": output.pk} for output in outputs],
                "location": 1,
                "status": 50,  # Item requires attention
            },
            expected_code=201
        )

        # There now should be 6 incomplete build outputs remaining
        self.assertEqual(self.build.incomplete_outputs.count(), 6)

        # And there should be 4 completed outputs
        outputs = self.build.complete_outputs
        self.assertEqual(outputs.count(), 4)

        for output in outputs:
            self.assertFalse(output.is_building)
            self.assertEqual(output.build, self.build)

        self.build.refresh_from_db()
        self.assertEqual(self.build.completed, 40)


class BuildAllocationTest(BuildAPITest):
    """
    Unit tests for allocation of stock items against a build order.

    For this test, we will be using Build ID=1;

    - This points to Part 100 (see fixture data in part.yaml)
    - This Part already has a BOM with 4 items (see fixture data in bom.yaml)
    - There are no BomItem objects yet created for this build

    """

    def setUp(self):

        super().setUp()

        self.assignRole('build.add')
        self.assignRole('build.change')

        self.url = reverse('api-build-allocate', kwargs={'pk': 1})

        self.build = Build.objects.get(pk=1)

        # Record number of build items which exist at the start of each test
        self.n = BuildItem.objects.count()

    def test_build_data(self):
        """
        Check that our assumptions about the particular BuildOrder are correct
        """

        self.assertEqual(self.build.part.pk, 100)

        # There should be 4x BOM items we can use
        self.assertEqual(self.build.part.bom_items.count(), 4)

        # No items yet allocated to this build
        self.assertEqual(self.build.allocated_stock.count(), 0)

    def test_get(self):
        """
        A GET request to the endpoint should return an error
        """

        self.get(self.url, expected_code=405)

    def test_options(self):
        """
        An OPTIONS request to the endpoint should return information about the endpoint
        """

        response = self.options(self.url, expected_code=200)

        self.assertIn("API endpoint to allocate stock items to a build order", str(response.data))

    def test_empty(self):
        """
        Test without any POST data
        """

        # Initially test with an empty data set
        data = self.post(self.url, {}, expected_code=400).data

        self.assertIn('This field is required', str(data['items']))

        # Now test but with an empty items list
        data = self.post(
            self.url,
            {
                "items": []
            },
            expected_code=400
        ).data

        self.assertIn('Allocation items must be provided', str(data))

        # No new BuildItem objects have been created during this test
        self.assertEqual(self.n, BuildItem.objects.count())

    def test_missing(self):
        """
        Test with missing data
        """

        # Missing quantity
        data = self.post(
            self.url,
            {
                "items": [
                    {
                        "bom_item": 1,  # M2x4 LPHS
                        "stock_item": 2,  # 5,000 screws available
                    }
                ]
            },
            expected_code=400
        ).data

        self.assertIn('This field is required', str(data["items"][0]["quantity"]))

        # Missing bom_item
        data = self.post(
            self.url,
            {
                "items": [
                    {
                        "stock_item": 2,
                        "quantity": 5000,
                    }
                ]
            },
            expected_code=400
        ).data

        self.assertIn("This field is required", str(data["items"][0]["bom_item"]))

        # Missing stock_item
        data = self.post(
            self.url,
            {
                "items": [
                    {
                        "bom_item": 1,
                        "quantity": 5000,
                    }
                ]
            },
            expected_code=400
        ).data

        self.assertIn("This field is required", str(data["items"][0]["stock_item"]))

        # No new BuildItem objects have been created during this test
        self.assertEqual(self.n, BuildItem.objects.count())

    def test_invalid_bom_item(self):
        """
        Test by passing an invalid BOM item
        """

        data = self.post(
            self.url,
            {
                "items": [
                    {
                        "bom_item": 5,
                        "stock_item": 11,
                        "quantity": 500,
                    }
                ]
            },
            expected_code=400
        ).data

        self.assertIn('must point to the same part', str(data))

    def test_valid_data(self):
        """
        Test with valid data.
        This should result in creation of a new BuildItem object
        """

        self.post(
            self.url,
            {
                "items": [
                    {
                        "bom_item": 1,
                        "stock_item": 2,
                        "quantity": 5000,
                    }
                ]
            },
            expected_code=201
        )

        # A new BuildItem should have been created
        self.assertEqual(self.n + 1, BuildItem.objects.count())

        allocation = BuildItem.objects.last()

        self.assertEqual(allocation.quantity, 5000)
        self.assertEqual(allocation.bom_item.pk, 1)
        self.assertEqual(allocation.stock_item.pk, 2)


class BuildListTest(BuildAPITest):
    """
    Tests for the BuildOrder LIST API
    """

    url = reverse('api-build-list')

    def test_get_all_builds(self):
        """
        Retrieve *all* builds via the API
        """

        builds = self.get(self.url)

        self.assertEqual(len(builds.data), 5)

        builds = self.get(self.url, data={'active': True})
        self.assertEqual(len(builds.data), 1)

        builds = self.get(self.url, data={'status': BuildStatus.COMPLETE})
        self.assertEqual(len(builds.data), 4)

        builds = self.get(self.url, data={'overdue': False})
        self.assertEqual(len(builds.data), 5)

        builds = self.get(self.url, data={'overdue': True})
        self.assertEqual(len(builds.data), 0)

    def test_overdue(self):
        """
        Create a new build, in the past
        """

        in_the_past = datetime.now().date() - timedelta(days=50)

        part = Part.objects.get(pk=50)

        Build.objects.create(
            part=part,
            quantity=10,
            title='Just some thing',
            status=BuildStatus.PRODUCTION,
            target_date=in_the_past
        )

        response = self.get(self.url, data={'overdue': True})

        builds = response.data

        self.assertEqual(len(builds), 1)

    def test_sub_builds(self):
        """
        Test the build / sub-build relationship
        """

        parent = Build.objects.get(pk=5)

        part = Part.objects.get(pk=50)

        n = Build.objects.count()

        # Make some sub builds
        for i in range(5):
            Build.objects.create(
                part=part,
                quantity=10,
                reference=f"build-000{i}",
                title=f"Sub build {i}",
                parent=parent
            )

        # And some sub-sub builds
        for sub_build in Build.objects.filter(parent=parent):

            for i in range(3):
                Build.objects.create(
                    part=part,
                    reference=f"{sub_build.reference}-00{i}-sub",
                    quantity=40,
                    title=f"sub sub build {i}",
                    parent=sub_build
                )

        # 20 new builds should have been created!
        self.assertEqual(Build.objects.count(), (n + 20))

        Build.objects.rebuild()

        # Search by parent
        response = self.get(self.url, data={'parent': parent.pk})

        builds = response.data

        self.assertEqual(len(builds), 5)

        # Search by ancestor
        response = self.get(self.url, data={'ancestor': parent.pk})

        builds = response.data

        self.assertEqual(len(builds), 20)