From 591134007ca70a542239badc61073f0be515abf4 Mon Sep 17 00:00:00 2001
From: Wu Cheng-Han <jacky_cute0808@hotmail.com>
Date: Sun, 18 Sep 2016 16:35:24 +0800
Subject: [PATCH] Update to support shortcuts which can add or delete symbol
 surround text

---
 public/js/index.js | 84 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

diff --git a/public/js/index.js b/public/js/index.js
index e192db5..b05c8d2 100644
--- a/public/js/index.js
+++ b/public/js/index.js
@@ -50,9 +50,93 @@ var defaultExtraKeys = {
     "Ctrl-C": function (cm) {
         if (!mac && cm.getOption('keyMap').substr(0, 3) === 'vim') document.execCommand("copy");
         else return CodeMirror.Pass;
+    },
+    "Ctrl-*": function (cm) {
+        wrapTextWith(cm, '*');
+    },
+    "Shift-Ctrl-8": function (cm) {
+        wrapTextWith(cm, '*');
+    },
+    "Ctrl-_": function (cm) {
+        wrapTextWith(cm, '_');
+    },
+    "Shift-Ctrl--": function (cm) {
+        wrapTextWith(cm, '_');
+    },
+    "Ctrl-~": function (cm) {
+        wrapTextWith(cm, '~');
+    },
+    "Shift-Ctrl-`": function (cm) {
+        wrapTextWith(cm, '~');
+    },
+    "Ctrl-^": function (cm) {
+        wrapTextWith(cm, '^');
+    },
+    "Shift-Ctrl-6": function (cm) {
+        wrapTextWith(cm, '^');
+    },
+    "Ctrl-+": function (cm) {
+        wrapTextWith(cm, '+');
+    },
+    "Shift-Ctrl-=": function (cm) {
+        wrapTextWith(cm, '+');
+    },
+    "Ctrl-=": function (cm) {
+        wrapTextWith(cm, '=');
+    },
+    "Shift-Ctrl-Backspace": function (cm) {
+        wrapTextWith(cm, 'Backspace');
     }
 };
 
+var wrapSymbols = ['*', '_', '~', '^', '+', '='];
+
+function wrapTextWith(cm, symbol) {
+    if (!cm.getSelection()) {
+        return CodeMirror.Pass;
+    } else {
+        var ranges = cm.listSelections();
+        for (var i = 0; i < ranges.length; i++) {
+            var range = ranges[i];
+            if (!range.empty()) {
+                var from = range.from(), to = range.to();
+                if (symbol !== 'Backspace') {
+                    cm.replaceRange(symbol, to, to, '+input');
+                    cm.replaceRange(symbol, from, from, '+input');
+                    // workaround selection range not correct after add symbol
+                    var _ranges = cm.listSelections();
+                    var anchorIndex = editor.indexFromPos(_ranges[i].anchor);
+                    var headIndex = editor.indexFromPos(_ranges[i].head);
+                    if (anchorIndex > headIndex) {
+                        _ranges[i].anchor.ch--;
+                    } else {
+                        _ranges[i].head.ch--;
+                    }
+                    cm.setSelections(_ranges);
+                } else {
+                    var preEndPos = {
+                        line: to.line,
+                        ch: to.ch + 1
+                    };
+                    var preText = cm.getRange(to, preEndPos);
+                    var preIndex = wrapSymbols.indexOf(preText);
+                    var postEndPos = {
+                        line: from.line,
+                        ch: from.ch - 1
+                    };
+                    var postText = cm.getRange(postEndPos, from);
+                    var postIndex = wrapSymbols.indexOf(postText);
+                    // check if surround symbol are list in array and matched 
+                    if (preIndex > -1 && postIndex > -1 && preIndex === postIndex) {
+                        cm.replaceRange("", to, preEndPos, '+delete');
+                        cm.replaceRange("", postEndPos, from, '+delete');
+                    }
+                }
+            }
+        }
+    }
+}
+
 var idleTime = 300000; //5 mins
 var updateViewDebounce = 200;
 var cursorMenuThrottle = 50;