Refactoring - moving key event handlers out of canvas object

[fnpeditor.git] / modules / documentCanvas / canvas / keyboard.js

diff --git a/modules/documentCanvas/canvas/keyboard.js b/modules/documentCanvas/canvas/keyboard.js
new file mode 100644 (file)
index 0000000..d851e3e
--- /dev/null
+++ b/modules/documentCanvas/canvas/keyboard.js
@@ -0,0 +1,197 @@
+define([
+'modules/documentCanvas/canvas/documentElement',
+'modules/documentCanvas/canvas/utils'
+], function(documentElement, utils) {
+    
+'use strict';
+
+
+var KEYS = {
+    ENTER: 13,
+    ARROW_LEFT: 37,
+    ARROW_UP: 38,
+    ARROW_RIGHT: 39,
+    ARROW_DOWN: 40,
+    BACKSPACE: 8,
+    DELETE: 46,
+    X: 88
+};
+
+var handleKey = function(event, canvas) {
+    handlers.some(function(handler) {
+        if(handles(handler, event) && handler[event.type]) {
+            handler[event.type](event, canvas);
+            return true;
+        }
+    });
+};
+
+var handles = function(handler, event) {
+    if(handler.key === event.which)
+        return true;
+    if(handler.keys && handler.keys.indexOf(event.which) !== -1)
+        return true;
+    return false;
+};
+
+var handlers = [];
+
+
+handlers.push({key: KEYS.ENTER,
+    keydown: function(event, canvas) {
+        event.preventDefault();
+        var cursor = canvas.getCursor(),
+            position = cursor.getPosition(),
+            element = position.element;
+
+        if(!cursor.isSelecting()) {
+            if(event.ctrlKey) {
+                var added = element.after({tag: 'block'});
+                added.append({text:''});
+                canvas.setCurrentElement(added, {caretTo: 'start'});
+
+            } else {
+
+                if(!(element.parent().parent())) {
+                    return false; // top level element is unsplittable
+                }
+
+                var elements = position.element.split({offset: position.offset}),
+                    newEmpty,
+                    goto,
+                    gotoOptions;
+
+                if(position.offsetAtBeginning)
+                    newEmpty = elements.first;
+                else if(position.offsetAtEnd)
+                    newEmpty = elements.second;
+                
+                if(newEmpty) {
+                    goto = newEmpty.append(documentElement.DocumentTextElement.create({text: ''}, this));
+                    gotoOptions = {};
+                } else {
+                    goto = elements.second;
+                    gotoOptions = {caretTo: 'start'};
+                }
+
+                canvas.setCurrentElement(goto, gotoOptions);
+            }
+        }
+    }
+});
+
+handlers.push({keys: [KEYS.ARROW_UP, KEYS.ARROW_DOWN, KEYS.ARROW_LEFT, KEYS.ARROW_RIGHT],
+    keydown: function(event, canvas) {
+        var position = canvas.getCursor().getPosition(),
+            element = position.element;
+        if(element && (element instanceof documentElement.DocumentTextElement) && element.isEmpty()) {
+            var direction, caretTo;
+            if(event.which === KEYS.ARROW_LEFT  || event.which === KEYS.ARROW_UP) {
+                direction = 'above';
+                caretTo = 'end';
+            } else {
+                direction = 'below';
+                caretTo = 'start';
+            }
+            var el = canvas.getDocumentElement(utils.nearestInDocumentOrder('[document-text-element]', direction, element.dom()[0]));
+            canvas.setCurrentElement(el, {caretTo: caretTo});
+        }
+    },
+    keyup: function(event, canvas) {
+        var element = canvas.getCursor().getPosition().element,
+            caretTo = false;
+        if(!element) {
+            // Chrome hack
+            var direction;
+            if(event.which === KEYS.ARROW_LEFT  || event.which === KEYS.ARROW_UP) {
+                direction = 'above';
+                caretTo = 'end';
+            } else {
+                direction = 'below';
+                caretTo = 'start';
+            }
+            element = canvas.getDocumentElement(utils.nearestInDocumentOrder('[document-text-element]:visible', direction, window.getSelection().focusNode));
+        }
+        canvas.setCurrentElement(element, {caretTo: caretTo});
+    }
+});
+
+
+var selectsWholeTextElement = function(cursor) {
+    if(cursor.isSelecting() && cursor.getSelectionStart().offsetAtBeginning && cursor.getSelectionEnd().offsetAtEnd)
+        return true;
+    return false;
+}
+
+handlers.push({key: KEYS.X,
+    keydown: function(event, canvas) {
+        if(event.ctrlKey && selectsWholeTextElement(canvas.getCursor()))
+            event.preventDefault();
+    }
+});
+
+handlers.push({keys: [KEYS.BACKSPACE, KEYS.DELETE],
+    keydown: function(event, canvas) {
+        var cursor = canvas.getCursor(),
+            position = canvas.getCursor().getPosition(),
+            element = position.element;
+
+        if(cursor.isSelecting() && !cursor.isSelectingWithinElement()) {
+            event.preventDefault();
+            return;
+        }
+            
+        var cursorAtOperationEdge = position.offsetAtBeginning;
+        if(event.which === KEYS.DELETE) {
+            cursorAtOperationEdge = position.offsetAtEnd;
+        }
+
+        var willDeleteWholeText = function() {
+            return element.getText().length === 1 || selectsWholeTextElement(cursor);
+        }
+
+        if(willDeleteWholeText()) {
+            event.preventDefault();
+            element.setText('');
+        }
+        else if(element.isEmpty()) {
+
+            var direction = 'above',
+                caretTo = 'end';
+                
+            if(event.which === KEYS.DELETE) {
+                direction = 'below';
+                caretTo = 'start';
+            }
+
+            event.preventDefault();
+
+            var parent = element.parent(),
+                grandParent = parent ? parent.parent() : null,
+                goto;
+            if(parent.children().length === 1 && parent.children()[0].sameNode(element)) {
+                if(grandParent && grandParent.children().length === 1) {
+                    goto = grandParent.append({text: ''});
+                } else {
+                    goto = canvas.getDocumentElement(utils.nearestInDocumentOrder('[document-text-element]', direction, element.dom()[0]));
+                }
+                parent.detach();
+            } else {
+                goto = canvas.getDocumentElement(utils.nearestInDocumentOrder('[document-text-element]', direction, element.dom()[0]));
+                element.detach();
+            }
+            canvas.setCurrentElement(goto, {caretTo: caretTo});
+            canvas.publisher('contentChanged');
+        }
+        else if(cursorAtOperationEdge) {
+            // todo
+            event.preventDefault();
+        }
+    }
+});
+
+return {
+    handleKey: handleKey
+};
+
+});
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