From 0722b8f529d24ad227c6d20bcfddbd53b06b4116 Mon Sep 17 00:00:00 2001
From: Val Erastov <xibyte@gmail.com>
Date: Thu, 8 Jan 2015 00:57:04 -0800
Subject: [PATCH] implement graph

---
 web/app/math/graph.js | 154 ++++++++++++++++++++++++++++++++++++++++++
 web/sketcher.html     |   3 +-
 2 files changed, 156 insertions(+), 1 deletion(-)
 create mode 100644 web/app/math/graph.js

diff --git a/web/app/math/graph.js b/web/app/math/graph.js
new file mode 100644
index 00000000..388b1882
--- /dev/null
+++ b/web/app/math/graph.js
@@ -0,0 +1,154 @@
+
+
+TCAD.graph = {};
+
+
+TCAD.graph.finaAllLoops = function(graph) {
+
+  var loops = [];
+  var visited = {};
+  function step(vertex, comesFrom, path) {
+    var i;
+    var vertexId = graph.id(vertex);
+    visited[vertexId] = true;
+    for (i = path.length - 1; i >= 0; --i) {
+      if (vertexId === graph.id(path[i])) {
+        loops.push(path.slice(i));
+        return;
+      }
+    }
+    
+    var next = graph.connections(vertex);
+    
+    path.push(vertex);
+    var needClone = false;
+    
+    VERTEX:
+    for (i = 0; i < next.length; i++) {
+      var v = next[i];
+      var nextId = graph.id(v);
+      if (nextId === comesFrom) {
+        continue;
+      }
+
+//      //avoid duplicates
+//      for (var li = loops.length - 1; li >= 0; --li) {
+//        var loop = loops[li];
+//        for (var j = 1; j < loop.length; j++) {
+//          if (loop[j - 1] == nextId && loop[j] == vertexId) {
+//            continue VERTEX;
+//          }
+//        }
+//      }
+      
+      var p = needClone ? path.slice(0) : path;
+      needClone = true;
+      step(v, vertexId, p);  
+    }
+    path.pop();
+  }
+
+  for (var i = 0; i < graph.size(); i++) {
+    var vertex = graph.at(i);
+    if (visited[graph.id(vertex)] !== true) {
+      step(vertex, -1, []);
+    }
+  }
+
+  //filter duplicates
+
+  function sameLoop(a, b) {
+    var bShift = b.indexOf(a[0]);
+    for (var i = 0; i < a.length; i++) {
+      var bUp = (bShift + i) % a.length;
+      var bDown = bShift - i;
+      if (bDown < 0) {
+        bDown = a.length + bDown;
+      }
+//      console.log("up: " + bUp + "; down: " + bDown);
+      if (a[i] != b[bUp] && a[i] != b[bDown] ) {
+        return false;
+      }
+    }
+    return true;
+  }
+
+  var duplicates = 0;
+  for (var i = 0; i < loops.length; i++) {
+    var a = loops[i];
+    if (a == null) continue;
+    for (var j = i + 1; j < loops.length; j++) {
+      var b = loops[j];
+      if (b == null || a.length !== b.length) {
+        continue;
+      }
+      if (sameLoop(a, b)) {
+        loops[j] = null;
+        ++ duplicates;
+      }
+    }
+  }
+  if (duplicates != 0) {
+    var filtered = [];
+    for (var i = 0; i < loops.length; i++) {
+      if (loops[i] != null) filtered.push(loops[i]);
+    }
+    loops = filtered;
+  }
+
+  return loops;
+};
+
+TCAD.graph.Graph = function(data) {
+
+  this.id = function(e) {
+    return e;
+  };
+
+  this.connections = function(e) {
+    return data[e];
+  };
+
+  this.at = function(index) {
+    return index;
+  };
+
+  this.size = function() {
+    return data.length;
+  };
+};
+
+TCAD.graph.test = function() {
+  var data = [
+    [],  
+    [2],
+    [1, 3, 9],
+    [2, 4],
+    [3, 9, 5, 8],
+    [4, 6],
+    [5, 8, 7],
+    [6],
+    [4, 6],
+    [2, 4]
+  ];
+
+  var graph = new TCAD.graph.Graph(data);
+  console.log(TCAD.graph.finaAllLoops(graph));
+};
+
+TCAD.graph.test0 = function() {
+  var data = [
+    [3, 1],
+    [0, 2, 8],
+    [1, 3, 7, 5],
+    [0, 2, 4],
+    [3, 5],
+    [4, 2, 6],
+    [5, 7],
+    [2, 6, 8],
+    [1, 7]
+  ];
+
+  var graph = new TCAD.graph.Graph(data);
+  console.log(TCAD.graph.finaAllLoops(graph));
+};
diff --git a/web/sketcher.html b/web/sketcher.html
index 47e84284..a8480bc0 100644
--- a/web/sketcher.html
+++ b/web/sketcher.html
@@ -206,7 +206,8 @@
   <script src="app/main2d.js"></script>
   <script src="app/workbench.js"></script>
   <script src="app/ui.js"></script>
-
+  <script src="app/math/graph.js"></script>
+  
   <script>
     function start() {
       var app = new TCAD.App2D();