feat: US-001 - Backend: DELETE endpoint for uncheck (toggle support)

dashboard/api.py

@@ -80,7 +80,9 @@ class TaskBoardHandler(SimpleHTTPRequestHandler):
             self.send_error(404)
     
     def do_DELETE(self):
-        if self.path.startswith('/api/habits/'):
+        if self.path.startswith('/api/habits/') and '/check' in self.path:
+            self.handle_habits_uncheck()
+        elif self.path.startswith('/api/habits/'):
             self.handle_habits_delete()
         else:
             self.send_error(404)
@@ -1771,6 +1773,88 @@ class TaskBoardHandler(SimpleHTTPRequestHandler):
         except Exception as e:
             self.send_json({'error': str(e)}, 500)
     
+    def handle_habits_uncheck(self):
+        """Uncheck a habit (remove completion for a specific date)."""
+        try:
+            # Extract habit ID from path (/api/habits/{id}/check)
+            path_parts = self.path.split('?')[0].split('/')
+            if len(path_parts) < 5:
+                self.send_json({'error': 'Invalid path'}, 400)
+                return
+            
+            habit_id = path_parts[3]
+            
+            # Parse query string for date parameter
+            parsed = urlparse(self.path)
+            query_params = parse_qs(parsed.query)
+            
+            # Get date from query string (required)
+            if 'date' not in query_params:
+                self.send_json({'error': 'date parameter is required (format: YYYY-MM-DD)'}, 400)
+                return
+            
+            target_date = query_params['date'][0]
+            
+            # Validate date format
+            try:
+                datetime.fromisoformat(target_date)
+            except ValueError:
+                self.send_json({'error': 'Invalid date format. Use YYYY-MM-DD'}, 400)
+                return
+            
+            # Read existing habits
+            if not HABITS_FILE.exists():
+                self.send_json({'error': 'Habit not found'}, 404)
+                return
+            
+            with open(HABITS_FILE, 'r', encoding='utf-8') as f:
+                habits_data = json.load(f)
+            
+            # Find habit
+            habit = None
+            for h in habits_data.get('habits', []):
+                if h['id'] == habit_id:
+                    habit = h
+                    break
+            
+            if not habit:
+                self.send_json({'error': 'Habit not found'}, 404)
+                return
+            
+            # Find and remove the completion for the specified date
+            completions = habit.get('completions', [])
+            completion_found = False
+            for i, completion in enumerate(completions):
+                if completion.get('date') == target_date:
+                    completions.pop(i)
+                    completion_found = True
+                    break
+            
+            if not completion_found:
+                self.send_json({'error': 'No completion found for the specified date'}, 404)
+                return
+            
+            # Recalculate streak after removing completion
+            current_streak = habits_helpers.calculate_streak(habit)
+            habit['streak']['current'] = current_streak
+            
+            # Update best streak if needed (best never decreases, but we keep it for consistency)
+            if current_streak > habit['streak']['best']:
+                habit['streak']['best'] = current_streak
+            
+            # Update timestamp
+            habit['updatedAt'] = datetime.now().isoformat()
+            habits_data['lastUpdated'] = habit['updatedAt']
+            
+            # Save to file
+            with open(HABITS_FILE, 'w', encoding='utf-8') as f:
+                json.dump(habits_data, f, indent=2)
+            
+            # Return updated habit
+            self.send_json(habit, 200)
+        except Exception as e:
+            self.send_json({'error': str(e)}, 500)
+    
     def handle_habits_skip(self):
         """Skip a day using a life to preserve streak."""
         try:

dashboard/tests/test_habits_api.py

@@ -91,6 +91,10 @@ def http_delete(path, port=8765):
     req = urllib.request.Request(url, method='DELETE')
     try:
         with urllib.request.urlopen(req) as response:
+            # Handle JSON response if present
+            if response.headers.get('Content-Type') == 'application/json':
+                return response.status, json.loads(response.read().decode())
+            else:
                 return response.status, None
     except urllib.error.HTTPError as e:
         return e.code, json.loads(e.read().decode()) if e.headers.get('Content-Type') == 'application/json' else {}
@@ -891,14 +895,189 @@ def test_skip_returns_updated_habit():
         server.shutdown()
         cleanup_test_env(temp_dir)
 
-# Test 35: Typecheck passes
+# Test 35: DELETE uncheck - removes completion for specified date
+def test_uncheck_removes_completion():
+    temp_dir = setup_test_env()
+    server = start_test_server()
+    
+    try:
+        # Create a habit
+        status, habit = http_post('/api/habits', {
+            'name': 'Daily Exercise',
+            'frequency': {'type': 'daily'}
+        })
+        assert status == 201
+        habit_id = habit['id']
+        
+        # Check in on a specific date
+        today = datetime.now().date().isoformat()
+        status, response = http_post(f'/api/habits/{habit_id}/check', {})
+        assert status == 200
+        assert len(response['completions']) == 1
+        assert response['completions'][0]['date'] == today
+        
+        # Uncheck the habit for today
+        status, response = http_delete(f'/api/habits/{habit_id}/check?date={today}')
+        assert status == 200
+        assert len(response['completions']) == 0, "Completion should be removed"
+        assert response['id'] == habit_id
+        
+        print("✓ Test 35: DELETE uncheck removes completion for specified date")
+    finally:
+        server.shutdown()
+        cleanup_test_env(temp_dir)
+
+# Test 36: DELETE uncheck - returns 404 if no completion for date
+def test_uncheck_no_completion_for_date():
+    temp_dir = setup_test_env()
+    server = start_test_server()
+    
+    try:
+        # Create a habit (but don't check in)
+        status, habit = http_post('/api/habits', {
+            'name': 'Daily Exercise',
+            'frequency': {'type': 'daily'}
+        })
+        assert status == 201
+        habit_id = habit['id']
+        
+        # Try to uncheck a date with no completion
+        today = datetime.now().date().isoformat()
+        status, response = http_delete(f'/api/habits/{habit_id}/check?date={today}')
+        assert status == 404
+        assert 'error' in response
+        assert 'No completion found' in response['error']
+        
+        print("✓ Test 36: DELETE uncheck returns 404 if no completion for date")
+    finally:
+        server.shutdown()
+        cleanup_test_env(temp_dir)
+
+# Test 37: DELETE uncheck - returns 404 if habit not found
+def test_uncheck_habit_not_found():
+    temp_dir = setup_test_env()
+    server = start_test_server()
+    
+    try:
+        today = datetime.now().date().isoformat()
+        status, response = http_delete(f'/api/habits/nonexistent-id/check?date={today}')
+        assert status == 404
+        assert 'error' in response
+        assert 'Habit not found' in response['error']
+        
+        print("✓ Test 37: DELETE uncheck returns 404 if habit not found")
+    finally:
+        server.shutdown()
+        cleanup_test_env(temp_dir)
+
+# Test 38: DELETE uncheck - recalculates streak correctly
+def test_uncheck_recalculates_streak():
+    temp_dir = setup_test_env()
+    server = start_test_server()
+    
+    try:
+        # Create a habit
+        status, habit = http_post('/api/habits', {
+            'name': 'Daily Exercise',
+            'frequency': {'type': 'daily'}
+        })
+        assert status == 201
+        habit_id = habit['id']
+        
+        # Check in for 3 consecutive days
+        today = datetime.now().date()
+        for i in range(3):
+            check_date = (today - timedelta(days=2-i)).isoformat()
+            # Manually add completion to the habit
+            with open(api.HABITS_FILE, 'r') as f:
+                data = json.load(f)
+            for h in data['habits']:
+                if h['id'] == habit_id:
+                    h['completions'].append({'date': check_date, 'type': 'check'})
+            with open(api.HABITS_FILE, 'w') as f:
+                json.dump(data, f)
+        
+        # Get habit to verify streak is 3
+        status, habit = http_get('/api/habits')
+        assert status == 200
+        habit = [h for h in habit if h['id'] == habit_id][0]
+        assert habit['current_streak'] == 3
+        
+        # Uncheck the middle day
+        middle_date = (today - timedelta(days=1)).isoformat()
+        status, response = http_delete(f'/api/habits/{habit_id}/check?date={middle_date}')
+        assert status == 200
+        
+        # Streak should now be 1 (only today counts)
+        assert response['streak']['current'] == 1, f"Expected streak 1, got {response['streak']['current']}"
+        
+        print("✓ Test 38: DELETE uncheck recalculates streak correctly")
+    finally:
+        server.shutdown()
+        cleanup_test_env(temp_dir)
+
+# Test 39: DELETE uncheck - returns updated habit object
+def test_uncheck_returns_updated_habit():
+    temp_dir = setup_test_env()
+    server = start_test_server()
+    
+    try:
+        # Create and check in
+        status, habit = http_post('/api/habits', {
+            'name': 'Daily Exercise',
+            'frequency': {'type': 'daily'}
+        })
+        habit_id = habit['id']
+        
+        today = datetime.now().date().isoformat()
+        status, _ = http_post(f'/api/habits/{habit_id}/check', {})
+        
+        # Uncheck and verify response structure
+        status, response = http_delete(f'/api/habits/{habit_id}/check?date={today}')
+        assert status == 200
+        assert 'id' in response
+        assert 'name' in response
+        assert 'completions' in response
+        assert 'streak' in response
+        assert 'updatedAt' in response
+        
+        print("✓ Test 39: DELETE uncheck returns updated habit object")
+    finally:
+        server.shutdown()
+        cleanup_test_env(temp_dir)
+
+# Test 40: DELETE uncheck - requires date parameter
+def test_uncheck_requires_date():
+    temp_dir = setup_test_env()
+    server = start_test_server()
+    
+    try:
+        # Create a habit
+        status, habit = http_post('/api/habits', {
+            'name': 'Daily Exercise',
+            'frequency': {'type': 'daily'}
+        })
+        habit_id = habit['id']
+        
+        # Try to uncheck without date parameter
+        status, response = http_delete(f'/api/habits/{habit_id}/check')
+        assert status == 400
+        assert 'error' in response
+        assert 'date parameter is required' in response['error']
+        
+        print("✓ Test 40: DELETE uncheck requires date parameter")
+    finally:
+        server.shutdown()
+        cleanup_test_env(temp_dir)
+
+# Test 41: Typecheck passes
 def test_typecheck():
     result = subprocess.run(
         ['python3', '-m', 'py_compile', str(Path(__file__).parent.parent / 'api.py')],
         capture_output=True
     )
     assert result.returncode == 0, f"Typecheck failed: {result.stderr.decode()}"
-    print("✓ Test 11: Typecheck passes")
+    print("✓ Test 41: Typecheck passes")
 
 if __name__ == '__main__':
     import subprocess
@@ -937,6 +1116,12 @@ if __name__ == '__main__':
     test_skip_not_found()
     test_skip_no_lives()
     test_skip_returns_updated_habit()
+    test_uncheck_removes_completion()
+    test_uncheck_no_completion_for_date()
+    test_uncheck_habit_not_found()
+    test_uncheck_recalculates_streak()
+    test_uncheck_returns_updated_habit()
+    test_uncheck_requires_date()
     test_typecheck()
     
-    print("\n✅ All 35 tests passed!\n")
+    print("\n✅ All 41 tests passed!\n")