Full rearchitecture using Claude

- event bus systen
- all components are independent
- preparation for web frontend

python-backend/tests/test_clock.py

@@ -0,0 +1,108 @@
+from __future__ import annotations
+
+import asyncio
+
+from musicmouse.clock import FakeClock, RealClock
+
+
+async def test_fake_clock_starts_at_zero_and_advances() -> None:
+    clock = FakeClock()
+    assert clock.now() == 0.0
+
+    await clock.advance(2.5)
+
+    assert clock.now() == 2.5
+
+
+async def test_sleep_blocks_until_time_is_advanced_past_the_deadline() -> None:
+    clock = FakeClock()
+    woken = asyncio.Event()
+
+    async def sleeper() -> None:
+        await clock.sleep(10)
+        woken.set()
+
+    task = asyncio.create_task(sleeper())
+    await clock.advance(9)
+    assert not woken.is_set()
+
+    await clock.advance(2)
+    assert woken.is_set()
+    await task
+
+
+async def test_sleepers_wake_in_deadline_order_regardless_of_start_order() -> None:
+    clock = FakeClock()
+    woken: list[str] = []
+
+    async def sleeper(name: str, delay: float) -> None:
+        await clock.sleep(delay)
+        woken.append(name)
+
+    tasks = [
+        asyncio.create_task(sleeper("late", 30)),
+        asyncio.create_task(sleeper("early", 10)),
+        asyncio.create_task(sleeper("middle", 20)),
+    ]
+    await clock.advance(60)
+
+    assert woken == ["early", "middle", "late"]
+    await asyncio.gather(*tasks)
+
+
+async def test_time_at_wake_up_is_the_deadline_not_the_target() -> None:
+    clock = FakeClock()
+    observed: list[float] = []
+
+    async def sleeper() -> None:
+        await clock.sleep(5)
+        observed.append(clock.now())
+
+    task = asyncio.create_task(sleeper())
+    await clock.advance(100)
+
+    assert observed == [5.0]
+    assert clock.now() == 100.0
+    await task
+
+
+async def test_idle_hook_runs_after_each_wake_up() -> None:
+    calls: list[int] = []
+
+    async def idle() -> None:
+        calls.append(1)
+
+    clock = FakeClock(idle=idle)
+
+    async def sleeper() -> None:
+        await clock.sleep(1)
+
+    task = asyncio.create_task(sleeper())
+    await clock.advance(2)
+
+    assert calls  # the bus got a chance to drain between virtual ticks
+    await task
+
+
+async def test_pending_timers_is_visible() -> None:
+    clock = FakeClock()
+    task = asyncio.create_task(clock.sleep(5))
+    await asyncio.sleep(0)
+
+    assert clock.pending_timers == 1
+    await clock.advance(5)
+    assert clock.pending_timers == 0
+    await task
+
+
+async def test_zero_sleep_just_yields() -> None:
+    clock = FakeClock()
+    await clock.sleep(0)
+    assert clock.now() == 0.0
+
+
+async def test_real_clock_measures_real_elapsed_time() -> None:
+    clock = RealClock()
+    before = clock.now()
+    await clock.advance(0.01)
+    assert clock.now() - before >= 0.005