Update timeline_generator.py

timeline_generator.py

@@ -5,7 +5,7 @@ import os
 
 def generate_timeline_diagram(json_input: str, output_format: str) -> str:
     """
-    Generates a timeline diagram from JSON input.
+    Generates a serpentine timeline diagram from JSON input.
 
     Args:
         json_input (str): A JSON string describing the timeline structure.
@@ -14,6 +14,7 @@ def generate_timeline_diagram(json_input: str, output_format: str) -> str:
     Expected JSON Format Example:
     {
       "title": "AI Development Timeline",
+      "events_per_row": 4,
       "events": [
         {
           "id": "event_1",
@@ -52,12 +53,12 @@ def generate_timeline_diagram(json_input: str, output_format: str) -> str:
             name='Timeline',
             format='png',
             graph_attr={
-                'rankdir': 'LR',        # Left-to-Right layout (horizontal timeline)
-                'splines': 'ortho',     # Straight lines
+                'rankdir': 'TB',        # Top-to-Bottom for better control
+                'splines': 'ortho',     # Straight lines with 90-degree bends
                 'bgcolor': 'white',     # White background
                 'pad': '0.5',           # Padding around the graph
-                'nodesep': '1.0',       # Spacing between nodes
-                'ranksep': '2.0'        # Spacing between ranks
+                'nodesep': '1.5',       # Spacing between nodes
+                'ranksep': '1.5'        # Spacing between ranks
             }
         )
         
@@ -65,6 +66,7 @@ def generate_timeline_diagram(json_input: str, output_format: str) -> str:
         
         title = data.get('title', '')
         events = data.get('events', [])
+        events_per_row = data.get('events_per_row', 4)  # Default to 4 events per row
         
         if not events:
             raise ValueError("Timeline must contain at least one event")
@@ -80,64 +82,118 @@ def generate_timeline_diagram(json_input: str, output_format: str) -> str:
                 fontcolor=base_color
             )
         
-        # Add timeline events
-        previous_event_id = None
+        # Calculate positions and create serpentine layout
         total_events = len(events)
+        previous_event_id = None
         
+        # Create invisible nodes for positioning and rank control
+        rows = []
+        current_row = []
+        
+        # Group events into rows
         for i, event in enumerate(events):
-            event_id = event.get('id', f'event_{i}')
-            event_label = event.get('label', f'Event {i+1}')
-            event_date = event.get('date', '')
-            event_description = event.get('description', '')
-            
-            # Create full label with date and description
-            if event_date and event_description:
-                full_label = f"{event_date}\\n{event_label}\\n{event_description}"
-            elif event_date:
-                full_label = f"{event_date}\\n{event_label}"
-            elif event_description:
-                full_label = f"{event_label}\\n{event_description}"
-            else:
-                full_label = event_label
-            
-            # Calculate color opacity based on position in timeline
-            if total_events == 1:
-                opacity = 'FF'
-            else:
-                opacity_value = int(255 * (1.0 - (i * 0.7 / (total_events - 1))))
-                opacity = format(opacity_value, '02x')
+            current_row.append(event)
+            if len(current_row) == events_per_row or i == total_events - 1:
+                rows.append(current_row)
+                current_row = []
+        
+        # Process each row and create serpentine connections
+        for row_idx, row in enumerate(rows):
+            # Determine if row should be reversed (serpentine pattern)
+            is_reversed = row_idx % 2 == 1
+            if is_reversed:
+                row = row[::-1]  # Reverse the row for serpentine effect
             
-            node_color = f"{base_color}{opacity}"
-            font_color = 'white' if i < total_events * 0.7 else 'black'
+            # Create invisible nodes for row positioning
+            row_nodes = []
             
-            # Add the event node
-            dot.node(
-                event_id,
-                full_label,
-                shape='box',
-                style='filled,rounded',
-                fillcolor=node_color,
-                fontcolor=font_color,
-                fontsize='12',
-                width='2.5',
-                height='1.2'
-            )
+            for event_idx, event in enumerate(row):
+                original_idx = events.index(event)
+                event_id = event.get('id', f'event_{original_idx}')
+                event_label = event.get('label', f'Event {original_idx+1}')
+                event_date = event.get('date', '')
+                event_description = event.get('description', '')
+                
+                # Create full label with date and description
+                if event_date and event_description:
+                    full_label = f"{event_date}\\n{event_label}\\n{event_description}"
+                elif event_date:
+                    full_label = f"{event_date}\\n{event_label}"
+                elif event_description:
+                    full_label = f"{event_label}\\n{event_description}"
+                else:
+                    full_label = event_label
+                
+                # Calculate color opacity based on original position in timeline
+                if total_events == 1:
+                    opacity = 'FF'
+                else:
+                    opacity_value = int(255 * (1.0 - (original_idx * 0.7 / (total_events - 1))))
+                    opacity = format(opacity_value, '02x')
+                
+                node_color = f"{base_color}{opacity}"
+                font_color = 'white' if original_idx < total_events * 0.7 else 'black'
+                
+                # Add the event node
+                dot.node(
+                    event_id,
+                    full_label,
+                    shape='box',
+                    style='filled,rounded',
+                    fillcolor=node_color,
+                    fontcolor=font_color,
+                    fontsize='12',
+                    width='2.5',
+                    height='1.2'
+                )
+                
+                row_nodes.append(event_id)
             
-            # Connect to previous event if exists
-            if previous_event_id:
+            # Create horizontal connections within the row
+            for i in range(len(row_nodes) - 1):
                 dot.edge(
-                    previous_event_id,
-                    event_id,
+                    row_nodes[i],
+                    row_nodes[i + 1],
                     color='#666666',
                     arrowsize='0.8',
                     penwidth='2'
                 )
             
-            # Connect title to first event if title exists
-            if title and i == 0:
-                dot.edge('title', event_id, style='invis')
+            # Connect to previous row (serpentine connection)
+            if row_idx > 0:
+                # Connect last node of previous row to first node of current row
+                prev_row_nodes = getattr(generate_timeline_diagram, 'prev_row_nodes', [])
+                if prev_row_nodes:
+                    # Connect the end of previous row to start of current row
+                    if (row_idx - 1) % 2 == 0:  # Previous row was left-to-right
+                        connection_start = prev_row_nodes[-1]  # Last node of previous row
+                    else:  # Previous row was right-to-left
+                        connection_start = prev_row_nodes[0]   # First node of previous row (which was last visually)
+                    
+                    if row_idx % 2 == 0:  # Current row is left-to-right
+                        connection_end = row_nodes[0]  # First node of current row
+                    else:  # Current row is right-to-left
+                        connection_end = row_nodes[-1]  # Last node of current row (which will be first visually)
+                    
+                    dot.edge(
+                        connection_start,
+                        connection_end,
+                        color='#666666',
+                        arrowsize='0.8',
+                        penwidth='2'
+                    )
+            
+            # Store current row nodes for next iteration
+            generate_timeline_diagram.prev_row_nodes = row_nodes
             
-            previous_event_id = event_id
+            # Connect title to first event if title exists and this is the first row
+            if title and row_idx == 0:
+                first_event = row_nodes[0] if row_idx % 2 == 0 else row_nodes[-1]
+                dot.edge('title', first_event, style='invis')
+        
+        # Clean up the stored attribute
+        if hasattr(generate_timeline_diagram, 'prev_row_nodes'):
+            delattr(generate_timeline_diagram, 'prev_row_nodes')
 
         with NamedTemporaryFile(delete=False, suffix=f'.{output_format}') as tmp:
             dot.render(tmp.name, format=output_format, cleanup=True)