it is working

src/crewai/flow/flow_visualizer.py

@@ -12,12 +12,10 @@ class FlowVisualizer(ABC):
             "bg": "#FFFFFF",
             "start": "#FF5A50",
             "method": "#333333",
-            "router_outline": "#FF5A50",
-            "edge": "#333333",
+            "router": "#FF8C00",
+            "edge": "#666666",
             "text": "#FFFFFF",
         }
-        self.node_rectangles = {}
-        self.node_positions = {}
 
     @abstractmethod
     def visualize(self, filename):
@@ -107,35 +105,50 @@ class GraphvizVisualizer(FlowVisualizer):
 class PyvisFlowVisualizer(FlowVisualizer):
     def visualize(self, filename):
         net = Network(
-            directed=True, height="750px", width="100%", bgcolor=self.colors["bg"]
+            directed=True,
+            height="750px",
+            width="100%",
+            bgcolor=self.colors["bg"],
+            layout=None,
         )
 
         # Define custom node styles
         node_styles = {
             "start": {
-                "color": self.colors["start"],
+                "color": self.colors.get("start", "#FF5A50"),
                 "shape": "box",
-                "font": {"color": self.colors["text"]},
+                "font": {"color": self.colors.get("text", "#FFFFFF")},
             },
             "method": {
-                "color": self.colors["method"],
+                "color": self.colors.get("method", "#333333"),
                 "shape": "box",
-                "font": {"color": self.colors["text"]},
+                "font": {"color": self.colors.get("text", "#FFFFFF")},
+            },
+            "router": {
+                "color": self.colors.get("router", "#FF8C00"),
+                "shape": "box",
+                "font": {"color": self.colors.get("text", "#FFFFFF")},
             },
-            # "router": {
-            #     "color": self.colors["router"],
-            #     "shape": "box",
-            #     "font": {"color": self.colors["text"]},
-            # },
         }
 
-        # Add nodes
-        for method_name, method in self.flow._methods.items():
-            if (
-                hasattr(method, "__is_start_method__")
-                or method_name in self.flow._listeners
-                or method_name in self.flow._routers.values()
-            ):
+        # Calculate levels for nodes
+        node_levels = self._calculate_node_levels()
+
+        # Assign positions to nodes based on levels
+        y_spacing = 150  # Adjust spacing between levels (positive for top-down)
+        x_spacing = 150  # Adjust spacing between nodes
+        level_nodes = {}
+
+        for method_name, level in node_levels.items():
+            level_nodes.setdefault(level, []).append(method_name)
+
+        # Compute positions
+        for level, nodes in level_nodes.items():
+            x_offset = -(len(nodes) - 1) * x_spacing / 2  # Center nodes horizontally
+            for i, method_name in enumerate(nodes):
+                x = x_offset + i * x_spacing
+                y = level * y_spacing  # Use level directly for y position
+                method = self.flow._methods.get(method_name)
                 if hasattr(method, "__is_start_method__"):
                     node_style = node_styles["start"]
                 elif method_name in self.flow._routers.values():
@@ -143,9 +156,17 @@ class PyvisFlowVisualizer(FlowVisualizer):
                 else:
                     node_style = node_styles["method"]
 
-                net.add_node(method_name, label=method_name, **node_style)
+                net.add_node(
+                    method_name,
+                    label=method_name,
+                    x=x,
+                    y=y,
+                    fixed=True,
+                    physics=False,  # Disable physics for fixed positioning
+                    **node_style,
+                )
 
-        # Add edges
+        # Add edges with curved lines
         for method_name in self.flow._listeners:
             condition_type, trigger_methods = self.flow._listeners[method_name]
             is_and_condition = condition_type == "AND"
@@ -154,17 +175,68 @@ class PyvisFlowVisualizer(FlowVisualizer):
                     net.add_edge(
                         trigger,
                         method_name,
-                        color=self.colors["edge"],
+                        color=self.colors.get("edge", "#666666"),
                         width=2,
                         arrows="to",
-                        dashes=is_and_condition,  # Dashed lines for AND conditions
+                        dashes=is_and_condition,
                         smooth={"type": "cubicBezier"},
                     )
 
+        # Set options for curved edges and disable physics
+        net.set_options(
+            """
+    var options = {
+      "physics": {
+        "enabled": false
+      },
+      "edges": {
+        "smooth": {
+          "enabled": true,
+          "type": "cubicBezier",
+          "roundness": 0.5
+        }
+      }
+    }
+    """
+        )
+
         # Generate and save the graph
         net.write_html(f"{filename}.html")
         print(f"Graph saved as {filename}.html")
 
+    def _calculate_node_levels(self):
+        levels = {}
+        queue = []
+        visited = set()
+
+        # Initialize start methods at level 0
+        for method_name, method in self.flow._methods.items():
+            if hasattr(method, "__is_start_method__"):
+                levels[method_name] = 0
+                queue.append(method_name)
+
+        # Breadth-first traversal to assign levels
+        while queue:
+            current = queue.pop(0)
+            current_level = levels[current]
+            visited.add(current)
+
+            # Get methods that listen to the current method
+            for listener_name, (
+                condition_type,
+                trigger_methods,
+            ) in self.flow._listeners.items():
+                if current in trigger_methods:
+                    if (
+                        listener_name not in levels
+                        or levels[listener_name] > current_level + 1
+                    ):
+                        levels[listener_name] = current_level + 1
+                        if listener_name not in visited:
+                            queue.append(listener_name)
+
+        return levels
+
 
 def is_graphviz_available():
     try: