feat(mma): Implement TrackDAG for dependency resolution and cycle detection

tests/test_dag_engine.py

@@ -0,0 +1,67 @@
+import pytest
+from models import Ticket
+from dag_engine import TrackDAG
+
+def test_get_ready_tasks_linear():
+    t1 = Ticket(id="T1", description="Task 1", status="completed", assigned_to="worker")
+    t2 = Ticket(id="T2", description="Task 2", status="todo", assigned_to="worker", depends_on=["T1"])
+    t3 = Ticket(id="T3", description="Task 3", status="todo", assigned_to="worker", depends_on=["T2"])
+    
+    dag = TrackDAG([t1, t2, t3])
+    ready = dag.get_ready_tasks()
+    assert len(ready) == 1
+    assert ready[0].id == "T2"
+
+def test_get_ready_tasks_branching():
+    t1 = Ticket(id="T1", description="Task 1", status="completed", assigned_to="worker")
+    t2 = Ticket(id="T2", description="Task 2", status="todo", assigned_to="worker", depends_on=["T1"])
+    t3 = Ticket(id="T3", description="Task 3", status="todo", assigned_to="worker", depends_on=["T1"])
+    
+    dag = TrackDAG([t1, t2, t3])
+    ready = dag.get_ready_tasks()
+    assert len(ready) == 2
+    ready_ids = {t.id for t in ready}
+    assert ready_ids == {"T2", "T3"}
+
+def test_has_cycle_no_cycle():
+    t1 = Ticket(id="T1", description="Task 1", status="todo", assigned_to="worker")
+    t2 = Ticket(id="T2", description="Task 2", status="todo", assigned_to="worker", depends_on=["T1"])
+    
+    dag = TrackDAG([t1, t2])
+    assert not dag.has_cycle()
+
+def test_has_cycle_direct_cycle():
+    t1 = Ticket(id="T1", description="Task 1", status="todo", assigned_to="worker", depends_on=["T2"])
+    t2 = Ticket(id="T2", description="Task 2", status="todo", assigned_to="worker", depends_on=["T1"])
+    
+    dag = TrackDAG([t1, t2])
+    assert dag.has_cycle()
+
+def test_has_cycle_indirect_cycle():
+    t1 = Ticket(id="T1", description="Task 1", status="todo", assigned_to="worker", depends_on=["T2"])
+    t2 = Ticket(id="T2", description="Task 2", status="todo", assigned_to="worker", depends_on=["T3"])
+    t3 = Ticket(id="T3", description="Task 3", status="todo", assigned_to="worker", depends_on=["T1"])
+    
+    dag = TrackDAG([t1, t2, t3])
+    assert dag.has_cycle()
+
+def test_has_cycle_complex_no_cycle():
+    # T1 -> T2, T1 -> T3, T2 -> T4, T3 -> T4
+    t1 = Ticket(id="T1", description="T1", status="todo", assigned_to="worker", depends_on=["T2", "T3"])
+    t2 = Ticket(id="T2", description="T2", status="todo", assigned_to="worker", depends_on=["T4"])
+    t3 = Ticket(id="T3", description="T3", status="todo", assigned_to="worker", depends_on=["T4"])
+    t4 = Ticket(id="T4", description="T4", status="todo", assigned_to="worker")
+    
+    dag = TrackDAG([t1, t2, t3, t4])
+    assert not dag.has_cycle()
+
+def test_get_ready_tasks_multiple_deps():
+    t1 = Ticket(id="T1", description="T1", status="completed", assigned_to="worker")
+    t2 = Ticket(id="T2", description="T2", status="completed", assigned_to="worker")
+    t3 = Ticket(id="T3", description="T3", status="todo", assigned_to="worker", depends_on=["T1", "T2"])
+    
+    dag = TrackDAG([t1, t2, t3])
+    assert [t.id for t in dag.get_ready_tasks()] == ["T3"]
+    
+    t2.status = "todo"
+    assert [t.id for t in dag.get_ready_tasks()] == ["T2"]