1(function() {
2  var DEFAULT_BRACKETS = "()[]{}''\"\"";
3  var SPACE_CHAR_REGEX = /\s/;
4
5  CodeMirror.defineOption("autoCloseBrackets", false, function(cm, val, old) {
6    var wasOn = old && old != CodeMirror.Init;
7    if (val && !wasOn)
8      cm.addKeyMap(buildKeymap(typeof val == "string" ? val : DEFAULT_BRACKETS));
9    else if (!val && wasOn)
10      cm.removeKeyMap("autoCloseBrackets");
11  });
12
13  function buildKeymap(pairs) {
14    var map = {
15      name : "autoCloseBrackets",
16      Backspace: function(cm) {
17        if (cm.somethingSelected()) return CodeMirror.Pass;
18        var cur = cm.getCursor(), line = cm.getLine(cur.line);
19        if (cur.ch && cur.ch < line.length &&
20            pairs.indexOf(line.slice(cur.ch - 1, cur.ch + 1)) % 2 == 0)
21          cm.replaceRange("", CodeMirror.Pos(cur.line, cur.ch - 1), CodeMirror.Pos(cur.line, cur.ch + 1));
22        else
23          return CodeMirror.Pass;
24      }
25    };
26    var closingBrackets = [];
27    for (var i = 0; i < pairs.length; i += 2) (function(left, right) {
28      if (left != right) closingBrackets.push(right);
29      function surround(cm) {
30          var selection = cm.getSelection();
31          cm.replaceSelection(left + selection + right);
32      }
33      function maybeOverwrite(cm) {
34        var cur = cm.getCursor(), ahead = cm.getRange(cur, CodeMirror.Pos(cur.line, cur.ch + 1));
35        if (ahead != right || cm.somethingSelected()) return CodeMirror.Pass;
36        else cm.execCommand("goCharRight");
37      }
38      map["'" + left + "'"] = function(cm) {
39        if (cm.somethingSelected()) return surround(cm);
40        if (left == right && maybeOverwrite(cm) != CodeMirror.Pass) return;
41        var cur = cm.getCursor(), ahead = CodeMirror.Pos(cur.line, cur.ch + 1);
42        var line = cm.getLine(cur.line), nextChar = line.charAt(cur.ch);
43        if (line.length == cur.ch || closingBrackets.indexOf(nextChar) >= 0 || SPACE_CHAR_REGEX.test(nextChar))
44          cm.replaceSelection(left + right, {head: ahead, anchor: ahead});
45        else
46          return CodeMirror.Pass;
47      };
48      if (left != right) map["'" + right + "'"] = maybeOverwrite;
49    })(pairs.charAt(i), pairs.charAt(i + 1));
50    return map;
51  }
52})();
53