只有hello包实现多跳，还没加入业务数据

具体的还要看opencode和gpt记录接着优化

sim/analysis_tools/topology.py

@@ -0,0 +1,93 @@
+"""
+Topology Analysis Tools.
+
+Functions for analyzing and exporting network topology.
+"""
+
+import json
+import os
+from typing import List, Dict, Any
+
+
+def export_topology_json(
+    nodes: List[Any], filepath: str = "analysis/topology_export.json"
+):
+    """
+    Export topology to JSON file.
+
+    Args:
+        nodes: List of Node objects
+        filepath: Output file path
+    """
+    topology = {"nodes": []}
+
+    for node in nodes:
+        node_info = {
+            "id": node.node_id,
+            "x": round(node.x, 2),
+            "y": round(node.y, 2),
+            "cost": int(node.routing.cost) if node.routing.cost != float("inf") else -1,
+            "parent": node.routing.parent,
+            "is_sink": node.is_sink,
+        }
+        topology["nodes"].append(node_info)
+
+    # Ensure directory exists
+    os.makedirs(os.path.dirname(filepath), exist_ok=True)
+
+    with open(filepath, "w") as f:
+        json.dump(topology, f, indent=2)
+
+    return topology
+
+
+def analyze_parent_tree(nodes: List[Any]) -> Dict[str, Any]:
+    """
+    Analyze the parent tree structure.
+
+    Returns:
+        Dictionary with tree analysis
+    """
+    # Build parent map
+    parent_map = {}
+    for node in nodes:
+        if node.routing.parent is not None:
+            parent_map[node.node_id] = node.routing.parent
+
+    # Count children per node
+    children_count = {}
+    for node_id, parent_id in parent_map.items():
+        if parent_id not in children_count:
+            children_count[parent_id] = 0
+        children_count[parent_id] += 1
+
+    # Find root (sink)
+    sink = next((n for n in nodes if n.is_sink), None)
+
+    return {
+        "parent_map": parent_map,
+        "children_count": children_count,
+        "sink_id": sink.node_id if sink else None,
+        "total_links": len(parent_map),
+    }
+
+
+def find_unreachable_nodes(nodes: List[Any]) -> List[int]:
+    """Find nodes without a valid route to sink."""
+    unreachable = []
+    for node in nodes:
+        if not node.is_sink:
+            if node.routing.parent is None or node.routing.cost == float("inf"):
+                unreachable.append(node.node_id)
+    return unreachable
+
+
+def calculate_hop_distribution(nodes: List[Any]) -> Dict[int, int]:
+    """Calculate hop count distribution."""
+    hop_dist = {}
+    for node in nodes:
+        if not node.is_sink:
+            cost = int(node.routing.cost) if node.routing.cost != float("inf") else -1
+            if cost >= 0:
+                hop_dist[cost] = hop_dist.get(cost, 0) + 1
+    return hop_dist