import pytest

from infrasynth.workflows.models import (
    Transition,
    Workflow,
    WorkflowAwareModel,
    WorkflowInstance,
    WorkflowNode,
)

pytestmark = pytest.mark.django_db


@pytest.fixture
def workflow(user):
    return Workflow.objects.create(slug="approval", name="Approval", created_by=user)


class TestWorkflow:
    def test_create(self):
        workflow = Workflow.objects.create(slug="approval", name="Approval")
        assert workflow.is_active is True
        assert str(workflow) == "Approval"

    def test_unique_slug(self):
        Workflow.objects.create(slug="approval", name="A")
        with pytest.raises(Exception):
            Workflow.objects.create(slug="approval", name="B")


class TestWorkflowNode:
    def test_create(self, workflow):
        node = WorkflowNode.objects.create(
            workflow=workflow,
            name="Start",
            node_type=WorkflowNode.NodeType.START,
        )
        assert node.node_type == "start"
        assert node.approval_strategy == "all"
        assert node.min_approvals == 1
        assert str(node) == "approval:Start"

    def test_unique_name_per_workflow(self, workflow):
        WorkflowNode.objects.create(workflow=workflow, name="A")
        with pytest.raises(Exception):
            WorkflowNode.objects.create(workflow=workflow, name="A")


class TestTransition:
    def test_create(self, workflow):
        start = WorkflowNode.objects.create(workflow=workflow, name="Start", node_type=WorkflowNode.NodeType.START)
        end = WorkflowNode.objects.create(workflow=workflow, name="End", node_type=WorkflowNode.NodeType.END)
        transition = Transition.objects.create(from_node=start, to_node=end, condition_slug="approved")
        assert transition.from_node == start
        assert transition.to_node == end
        assert str(transition) == "approval:Start → approval:End"


class TestWorkflowInstance:
    def test_default_status(self, workflow, user):
        instance = WorkflowInstance.objects.create(workflow=workflow, owner=user)
        assert instance.status == WorkflowInstance.Status.IN_PROGRESS
        assert instance.completed_at is None


class TestWorkflowAwareModel:
    def test_abstract_with_instance_fk(self):
        from django.db.models import ForeignKey

        assert WorkflowAwareModel._meta.abstract is True
        field = WorkflowAwareModel._meta.get_field("workflow_instance")
        assert isinstance(field, ForeignKey)
        assert field.null is True
        assert field.blank is True

    def test_assignable_workflow_instance(self, workflow, user):
        WorkflowInstance.objects.create(workflow=workflow, owner=user)
        assert workflow.instances.count() == 1