emergency: add route selection failure debug

vendor/clouds3d.js

@@ -3613,6 +3613,7 @@ function selectEmergencyRoutes() {
     var top = pool.slice(0, Math.max(EMERGENCY_COUNT * 8, 24));
     emergencyShuffle(top);
     var used = {};
+    var routeFailures = [];
     for (var r = 0; r < top.length && emergencyRoutes.length < EMERGENCY_COUNT; r++) {
         var cand = top[r];
         var usedKey = cand.netKey + ':' + cand.ci;
@@ -3623,7 +3624,14 @@ function selectEmergencyRoutes() {
         var base = route.length ? route[0].d : 0;
         for (var rp = 0; rp < route.length; rp++) route[rp].d -= base;
         var len = route.length ? route[route.length - 1].d : 0;
-        if (len <= 0) continue;
+        if (len <= 0) {
+            routeFailures.push({
+                netKey: cand.netKey, ci: cand.ci, lenKm: +cand.lenKm.toFixed(1),
+                nearKm: +(cand.near * KM_PER_TILE).toFixed(1), reverse: cand.reverse,
+                pts: route.length, rawLen: +(cand.len * KM_PER_TILE).toFixed(1)
+            });
+            continue;
+        }
         emergencyRoutes.push({ pts: route, len: len, lenKm: len * KM_PER_TILE, nearKm: cand.near * KM_PER_TILE });
     }
     for (var v = 0; v < emergencyRoutes.length; v++) {
@@ -3646,6 +3654,13 @@ function selectEmergencyRoutes() {
         } : null,
         poolMode: poolMode,
         candidates: pool.length,
+        candidateSample: top.slice(0, 5).map(function (c) {
+            return {
+                netKey: c.netKey, ci: c.ci, lenKm: +c.lenKm.toFixed(1),
+                nearKm: +(c.near * KM_PER_TILE).toFixed(1), reverse: c.reverse
+            };
+        }),
+        routeFailures: routeFailures.slice(0, 5),
         networks: nets.map(function (n) { return { key: n.key, chains: n.net.cnts.length }; }),
         routes: emergencyRoutes.map(function (r) { return { km: +r.lenKm.toFixed(1), nearKm: +r.nearKm.toFixed(1) }; })
     };