codemirror binding

src/Bindings/CodeMirrorBinding/CodeMirrorBinding.js

@@ -0,0 +1,67 @@
+import Binding from '../Binding.js'
+
+function typeObserver (event) {
+  this._mutualExclude(() => {
+    const codeMirror = this.target;
+    var deltas = event.delta;
+    var index = 0;
+    var from = codeMirror.posFromIndex(index);
+    for (var i = 0; i < deltas.length; i++) {
+        var delta = deltas[i];
+        if (delta.retain) {
+            index = delta.retain;
+            from = codeMirror.posFromIndex(index);
+        } else if (delta.insert) {
+            codeMirror.replaceRange(delta.insert, from, from)
+        } else if (delta.delete) {
+            codeMirror.replaceRange('', from, codeMirror.posFromIndex(index + delta.delete))
+        }
+    }
+  });
+}
+
+function codeMirrorObserver(codeMirror, deltas) {
+  this._mutualExclude(() => {
+    for (var i = 0; i < deltas.length; i++) {
+      var delta = deltas[i]
+      var start = codeMirror.indexFromPos(delta.from)
+      // apply the delete operation first
+      if (delta.removed.length > 0) {
+        var delLength = 0
+        for (var j = 0; j < delta.removed.length; j++) {
+          delLength += delta.removed[j].length
+        }
+        // "enter" is also a character in our case
+        delLength += delta.removed.length - 1
+        this.type.delete(start, delLength)
+      }
+      // apply insert operation
+      this.type.insert(start, delta.text.join('\n'))
+    }
+  });
+}
+
+/**
+ * A binding that binds a YText to a codemirror.
+ *
+ * This binding is automatically destroyed when its parent is deleted.
+ *
+ */
+export default class CodeMirrorBinding extends Binding {
+  constructor (textType, codeMirror) {
+    super(textType, codeMirror)
+    // set initial value
+    codeMirror.setValue(textType.toString())
+    // Observers are handled by this class
+    this._typeObserver = typeObserver.bind(this)
+    this._codeMirrorObserver = codeMirrorObserver.bind(this)
+    textType.observe(this._typeObserver)
+    codeMirror.on('changes', this._codeMirrorObserver)
+  }
+  destroy () {
+    // Remove everything that is handled by this class
+    this.type.unobserve(this._typeObserver)
+    this.target.unobserve(this._codeMirrorObserver)
+    super.destroy()
+  }
+}

src/Y.dist.js

@@ -20,6 +20,7 @@ import { registerStruct } from './Util/structReferences.js'
 import TextareaBinding from './Bindings/TextareaBinding/TextareaBinding.js'
 import QuillBinding from './Bindings/QuillBinding/QuillBinding.js'
 import DomBinding from './Bindings/DomBinding/DomBinding.js'
+import CodeMirrorBinding from './Bindings/CodeMirrorBinding/CodeMirrorBinding.js'
 import { toBinary, fromBinary } from './MessageHandler/binaryEncode.js'
 
 import debug from 'debug'
@@ -40,6 +41,7 @@ Y.XmlHook = YXmlHook
 Y.TextareaBinding = TextareaBinding
 Y.QuillBinding = QuillBinding
 Y.DomBinding = DomBinding
+Y.CodeMirrorBinding = CodeMirrorBinding
 
 DomBinding.domToType = domToType
 DomBinding.domsToTypes = domsToTypes