feat(adapter): implement click-anchored segmentation

ai_mouse/data_adapters/balabit.py

@@ -82,8 +82,40 @@ def segment_by_clicks(
     window_ms: int,
     session_id: str,
 ) -> list[Segment]:
-    """Stub — implemented in Task 4."""
+    """Extract click-anchored segments from a session.
-    raise NotImplementedError
+
+    For each Left-button Pressed event, collect all Move events within
+    [click_t - window_ms, click_t) into one segment.
+
+    Args:
+        events: Full session events (any state, any order is OK but typically sorted).
+        window_ms: How far back to look before each click.
+        session_id: String tag attached to every segment for debugging.
+
+    Returns:
+        List of Segment, one per Left Pressed event that has at least one preceding Move.
+    """
+    segments: list[Segment] = []
+    for ev in events:
+        if ev.state != "Pressed" or ev.button != "Left":
+            continue
+        click_t = ev.t_ms
+        window_start = click_t - window_ms
+        moves = [
+            m for m in events
+            if m.state == "Move" and window_start <= m.t_ms < click_t
+        ]
+        if not moves:
+            continue
+        moves.sort(key=lambda m: m.t_ms)
+        segments.append(Segment(
+            events=moves,
+            click_x=ev.x,
+            click_y=ev.y,
+            click_t_ms=click_t,
+            session_id=session_id,
+        ))
+    return segments
 
 
 def filter_segments(

tests/test_balabit_adapter.py

@@ -93,3 +93,95 @@ class TestParseSessionCsv:
         csv.write_text("record timestamp,client timestamp,button,state,x,y\n", encoding="utf-8")
         events = parse_session_csv(csv)
         assert events == []
+
+
+class TestSegmentByClicks:
+    def _make_event(self, t_ms: int, state: str, x: int, y: int, button: str = "NoButton"):
+        from ai_mouse.data_adapters.balabit import MouseEvent
+        return MouseEvent(t_ms=t_ms, button=button, state=state, x=x, y=y)
+
+    def test_one_click_one_segment(self):
+        from ai_mouse.data_adapters.balabit import segment_by_clicks
+        events = [
+            self._make_event(0, "Move", 10, 20),
+            self._make_event(100, "Move", 50, 60),
+            self._make_event(500, "Move", 100, 100),
+            self._make_event(600, "Pressed", 110, 110, button="Left"),
+        ]
+        segments = segment_by_clicks(events, window_ms=1200, session_id="test_s1")
+        assert len(segments) == 1
+        seg = segments[0]
+        assert seg.click_x == 110
+        assert seg.click_y == 110
+        assert seg.click_t_ms == 600
+        assert len(seg.events) == 3
+        assert seg.session_id == "test_s1"
+
+    def test_window_excludes_old_events(self):
+        """Move events earlier than (click_t - window_ms) are dropped."""
+        from ai_mouse.data_adapters.balabit import segment_by_clicks
+        events = [
+            self._make_event(0, "Move", 10, 20),       # too old
+            self._make_event(100, "Move", 20, 30),     # too old
+            self._make_event(900, "Move", 30, 40),     # in window
+            self._make_event(1000, "Pressed", 40, 50, button="Left"),
+        ]
+        segments = segment_by_clicks(events, window_ms=200, session_id="s")
+        assert len(segments) == 1
+        assert len(segments[0].events) == 1
+        assert segments[0].events[0].t_ms == 900
+
+    def test_multiple_clicks_multiple_segments(self):
+        from ai_mouse.data_adapters.balabit import segment_by_clicks
+        events = [
+            self._make_event(0, "Move", 10, 20),
+            self._make_event(100, "Pressed", 50, 50, button="Left"),
+            self._make_event(200, "Released", 50, 50, button="Left"),
+            self._make_event(300, "Move", 60, 60),
+            self._make_event(400, "Move", 70, 70),
+            self._make_event(500, "Pressed", 80, 80, button="Left"),
+        ]
+        segments = segment_by_clicks(events, window_ms=1200, session_id="s")
+        assert len(segments) == 2
+        assert segments[0].click_x == 50
+        assert segments[1].click_x == 80
+        # Second segment's events must not include the first Pressed
+        for e in segments[1].events:
+            assert e.state == "Move"
+
+    def test_skips_pressed_with_non_left_button(self):
+        """Right-clicks and wheel-clicks don't anchor segments (only Left)."""
+        from ai_mouse.data_adapters.balabit import segment_by_clicks
+        events = [
+            self._make_event(0, "Move", 10, 20),
+            self._make_event(100, "Pressed", 50, 50, button="Right"),  # ignored
+            self._make_event(200, "Move", 60, 60),
+            self._make_event(300, "Pressed", 70, 70, button="Left"),   # anchor
+        ]
+        segments = segment_by_clicks(events, window_ms=1200, session_id="s")
+        assert len(segments) == 1
+        assert segments[0].click_x == 70
+
+    def test_no_clicks_returns_empty(self):
+        from ai_mouse.data_adapters.balabit import segment_by_clicks
+        events = [
+            self._make_event(0, "Move", 10, 20),
+            self._make_event(100, "Move", 20, 30),
+        ]
+        segments = segment_by_clicks(events, window_ms=1200, session_id="s")
+        assert segments == []
+
+    def test_excludes_drag_events(self):
+        """Drag events are not Move; segment should only include Move."""
+        from ai_mouse.data_adapters.balabit import segment_by_clicks
+        events = [
+            self._make_event(0, "Move", 10, 20),
+            self._make_event(100, "Drag", 30, 40),       # not Move
+            self._make_event(200, "Move", 50, 60),
+            self._make_event(300, "Pressed", 70, 80, button="Left"),
+        ]
+        segments = segment_by_clicks(events, window_ms=1200, session_id="s")
+        assert len(segments) == 1
+        # Drag event should not appear in seg.events
+        assert all(e.state == "Move" for e in segments[0].events)
+        assert len(segments[0].events) == 2