instiki/public/svg-edit/editor/history.js
2011-02-03 11:13:18 -06:00

601 lines
20 KiB
JavaScript

/**
* Package: svedit.history
*
* Licensed under the Apache License, Version 2
*
* Copyright(c) 2010 Jeff Schiller
*/
// Dependencies:
// 1) jQuery
// 2) svgtransformlist.js
// 3) svgutils.js
var svgedit = svgedit || {};
(function() {
if (!svgedit.history) {
svgedit.history = {};
}
// Group: Undo/Redo history management
svgedit.history.HistoryEventTypes = {
BEFORE_APPLY: 'before_apply',
AFTER_APPLY: 'after_apply',
BEFORE_UNAPPLY: 'before_unapply',
AFTER_UNAPPLY: 'after_unapply'
};
var removedElements = {};
/**
* Interface: svgedit.history.HistoryCommand
* An interface that all command objects must implement.
*
* interface svgedit.history.HistoryCommand {
* void apply(svgedit.history.HistoryEventHandler);
* void unapply(svgedit.history.HistoryEventHandler);
* Element[] elements();
* String getText();
*
* static String type();
* }
*
* Interface: svgedit.history.HistoryEventHandler
* An interface for objects that will handle history events.
*
* interface svgedit.history.HistoryEventHandler {
* void handleHistoryEvent(eventType, command);
* }
*
* eventType is a string conforming to one of the HistoryEvent types.
* command is an object fulfilling the HistoryCommand interface.
*/
// Class: svgedit.history.MoveElementCommand
// implements svgedit.history.HistoryCommand
// History command for an element that had its DOM position changed
//
// Parameters:
// elem - The DOM element that was moved
// oldNextSibling - The element's next sibling before it was moved
// oldParent - The element's parent before it was moved
// text - An optional string visible to user related to this change
svgedit.history.MoveElementCommand = function(elem, oldNextSibling, oldParent, text) {
this.elem = elem;
this.text = text ? ("Move " + elem.tagName + " to " + text) : ("Move " + elem.tagName);
this.oldNextSibling = oldNextSibling;
this.oldParent = oldParent;
this.newNextSibling = elem.nextSibling;
this.newParent = elem.parentNode;
};
svgedit.history.MoveElementCommand.type = function() { return 'svgedit.history.MoveElementCommand'; }
svgedit.history.MoveElementCommand.prototype.type = svgedit.history.MoveElementCommand.type;
// Function: svgedit.history.MoveElementCommand.getText
svgedit.history.MoveElementCommand.prototype.getText = function() {
return this.text;
};
// Function: svgedit.history.MoveElementCommand.apply
// Re-positions the element
svgedit.history.MoveElementCommand.prototype.apply = function(handler) {
// TODO(codedread): Refactor this common event code into a base HistoryCommand class.
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_APPLY, this);
}
this.elem = this.newParent.insertBefore(this.elem, this.newNextSibling);
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_APPLY, this);
}
};
// Function: svgedit.history.MoveElementCommand.unapply
// Positions the element back to its original location
svgedit.history.MoveElementCommand.prototype.unapply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_UNAPPLY, this);
}
this.elem = this.oldParent.insertBefore(this.elem, this.oldNextSibling);
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_UNAPPLY, this);
}
};
// Function: svgedit.history.MoveElementCommand.elements
// Returns array with element associated with this command
svgedit.history.MoveElementCommand.prototype.elements = function() {
return [this.elem];
};
// Class: svgedit.history.InsertElementCommand
// implements svgedit.history.HistoryCommand
// History command for an element that was added to the DOM
//
// Parameters:
// elem - The newly added DOM element
// text - An optional string visible to user related to this change
svgedit.history.InsertElementCommand = function(elem, text) {
this.elem = elem;
this.text = text || ("Create " + elem.tagName);
this.parent = elem.parentNode;
this.nextSibling = this.elem.nextSibling;
};
svgedit.history.InsertElementCommand.type = function() { return 'svgedit.history.InsertElementCommand'; }
svgedit.history.InsertElementCommand.prototype.type = svgedit.history.InsertElementCommand.type;
// Function: svgedit.history.InsertElementCommand.getText
svgedit.history.InsertElementCommand.prototype.getText = function() {
return this.text;
};
// Function: svgedit.history.InsertElementCommand.apply
// Re-Inserts the new element
svgedit.history.InsertElementCommand.prototype.apply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_APPLY, this);
}
this.elem = this.parent.insertBefore(this.elem, this.nextSibling);
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_APPLY, this);
}
};
// Function: svgedit.history.InsertElementCommand.unapply
// Removes the element
svgedit.history.InsertElementCommand.prototype.unapply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_UNAPPLY, this);
}
this.parent = this.elem.parentNode;
this.elem = this.elem.parentNode.removeChild(this.elem);
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_UNAPPLY, this);
}
};
// Function: svgedit.history.InsertElementCommand.elements
// Returns array with element associated with this command
svgedit.history.InsertElementCommand.prototype.elements = function() {
return [this.elem];
};
// Class: svgedit.history.RemoveElementCommand
// implements svgedit.history.HistoryCommand
// History command for an element removed from the DOM
//
// Parameters:
// elem - The removed DOM element
// oldNextSibling - the DOM element's nextSibling when it was in the DOM
// oldParent - The DOM element's parent
// text - An optional string visible to user related to this change
svgedit.history.RemoveElementCommand = function(elem, oldNextSibling, oldParent, text) {
this.elem = elem;
this.text = text || ("Delete " + elem.tagName);
this.nextSibling = oldNextSibling;
this.parent = oldParent;
// special hack for webkit: remove this element's entry in the svgTransformLists map
svgedit.transformlist.removeElementFromListMap(elem);
};
svgedit.history.RemoveElementCommand.type = function() { return 'svgedit.history.RemoveElementCommand'; }
svgedit.history.RemoveElementCommand.prototype.type = svgedit.history.RemoveElementCommand.type;
// Function: svgedit.history.RemoveElementCommand.getText
svgedit.history.RemoveElementCommand.prototype.getText = function() {
return this.text;
};
// Function: RemoveElementCommand.apply
// Re-removes the new element
svgedit.history.RemoveElementCommand.prototype.apply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_APPLY, this);
}
svgedit.transformlist.removeElementFromListMap(this.elem);
this.parent = this.elem.parentNode;
this.elem = this.parent.removeChild(this.elem);
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_APPLY, this);
}
};
// Function: RemoveElementCommand.unapply
// Re-adds the new element
svgedit.history.RemoveElementCommand.prototype.unapply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_UNAPPLY, this);
}
svgedit.transformlist.removeElementFromListMap(this.elem);
if(this.nextSibling == null) {
console.log('Error: reference element was lost');
}
this.parent.insertBefore(this.elem, this.nextSibling);
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_UNAPPLY, this);
}
};
// Function: RemoveElementCommand.elements
// Returns array with element associated with this command
svgedit.history.RemoveElementCommand.prototype.elements = function() {
return [this.elem];
};
// Class: svgedit.history.ChangeElementCommand
// implements svgedit.history.HistoryCommand
// History command to make a change to an element.
// Usually an attribute change, but can also be textcontent.
//
// Parameters:
// elem - The DOM element that was changed
// attrs - An object with the attributes to be changed and the values they had *before* the change
// text - An optional string visible to user related to this change
svgedit.history.ChangeElementCommand = function(elem, attrs, text) {
this.elem = elem;
this.text = text ? ("Change " + elem.tagName + " " + text) : ("Change " + elem.tagName);
this.newValues = {};
this.oldValues = attrs;
for (var attr in attrs) {
if (attr == "#text") this.newValues[attr] = elem.textContent;
else if (attr == "#href") this.newValues[attr] = svgedit.utilities.getHref(elem);
else this.newValues[attr] = elem.getAttribute(attr);
}
};
svgedit.history.ChangeElementCommand.type = function() { return 'svgedit.history.ChangeElementCommand'; }
svgedit.history.ChangeElementCommand.prototype.type = svgedit.history.ChangeElementCommand.type;
// Function: svgedit.history.ChangeElementCommand.getText
svgedit.history.ChangeElementCommand.prototype.getText = function() {
return this.text;
};
// Function: svgedit.history.ChangeElementCommand.apply
// Performs the stored change action
svgedit.history.ChangeElementCommand.prototype.apply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_APPLY, this);
}
var bChangedTransform = false;
for(var attr in this.newValues ) {
if (this.newValues[attr]) {
if (attr == "#text") this.elem.textContent = this.newValues[attr];
else if (attr == "#href") svgedit.utilities.setHref(this.elem, this.newValues[attr])
else this.elem.setAttribute(attr, this.newValues[attr]);
}
else {
if (attr == "#text") {
this.elem.textContent = "";
}
else {
this.elem.setAttribute(attr, "");
this.elem.removeAttribute(attr);
}
}
if (attr == "transform") { bChangedTransform = true; }
}
// relocate rotational transform, if necessary
if(!bChangedTransform) {
var angle = svgedit.utilities.getRotationAngle(this.elem);
if (angle) {
var bbox = elem.getBBox();
var cx = bbox.x + bbox.width/2,
cy = bbox.y + bbox.height/2;
var rotate = ["rotate(", angle, " ", cx, ",", cy, ")"].join('');
if (rotate != elem.getAttribute("transform")) {
elem.setAttribute("transform", rotate);
}
}
}
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_APPLY, this);
}
return true;
};
// Function: svgedit.history.ChangeElementCommand.unapply
// Reverses the stored change action
svgedit.history.ChangeElementCommand.prototype.unapply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_UNAPPLY, this);
}
var bChangedTransform = false;
for(var attr in this.oldValues ) {
if (this.oldValues[attr]) {
if (attr == "#text") this.elem.textContent = this.oldValues[attr];
else if (attr == "#href") svgedit.utilities.setHref(this.elem, this.oldValues[attr]);
else this.elem.setAttribute(attr, this.oldValues[attr]);
}
else {
if (attr == "#text") {
this.elem.textContent = "";
}
else this.elem.removeAttribute(attr);
}
if (attr == "transform") { bChangedTransform = true; }
}
// relocate rotational transform, if necessary
if(!bChangedTransform) {
var angle = svgedit.utilities.getRotationAngle(this.elem);
if (angle) {
var bbox = elem.getBBox();
var cx = bbox.x + bbox.width/2,
cy = bbox.y + bbox.height/2;
var rotate = ["rotate(", angle, " ", cx, ",", cy, ")"].join('');
if (rotate != elem.getAttribute("transform")) {
elem.setAttribute("transform", rotate);
}
}
}
// Remove transformlist to prevent confusion that causes bugs like 575.
svgedit.transformlist.removeElementFromListMap(this.elem);
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_UNAPPLY, this);
}
return true;
};
// Function: ChangeElementCommand.elements
// Returns array with element associated with this command
svgedit.history.ChangeElementCommand.prototype.elements = function() {
return [this.elem];
};
// TODO: create a 'typing' command object that tracks changes in text
// if a new Typing command is created and the top command on the stack is also a Typing
// and they both affect the same element, then collapse the two commands into one
// Class: svgedit.history.BatchCommand
// implements svgedit.history.HistoryCommand
// History command that can contain/execute multiple other commands
//
// Parameters:
// text - An optional string visible to user related to this change
svgedit.history.BatchCommand = function(text) {
this.text = text || "Batch Command";
this.stack = [];
};
svgedit.history.BatchCommand.type = function() { return 'svgedit.history.BatchCommand'; }
svgedit.history.BatchCommand.prototype.type = svgedit.history.BatchCommand.type;
// Function: svgedit.history.BatchCommand.getText
svgedit.history.BatchCommand.prototype.getText = function() {
return this.text;
};
// Function: svgedit.history.BatchCommand.apply
// Runs "apply" on all subcommands
svgedit.history.BatchCommand.prototype.apply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_APPLY, this);
}
var len = this.stack.length;
for (var i = 0; i < len; ++i) {
this.stack[i].apply(handler);
}
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_APPLY, this);
}
};
// Function: svgedit.history.BatchCommand.unapply
// Runs "unapply" on all subcommands
svgedit.history.BatchCommand.prototype.unapply = function(handler) {
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.BEFORE_UNAPPLY, this);
}
for (var i = this.stack.length-1; i >= 0; i--) {
this.stack[i].unapply(handler);
}
if (handler) {
handler.handleHistoryEvent(svgedit.history.HistoryEventTypes.AFTER_UNAPPLY, this);
}
};
// Function: svgedit.history.BatchCommand.elements
// Iterate through all our subcommands and returns all the elements we are changing
svgedit.history.BatchCommand.prototype.elements = function() {
var elems = [];
var cmd = this.stack.length;
while (cmd--) {
var thisElems = this.stack[cmd].elements();
var elem = thisElems.length;
while (elem--) {
if (elems.indexOf(thisElems[elem]) == -1) elems.push(thisElems[elem]);
}
}
return elems;
};
// Function: svgedit.history.BatchCommand.addSubCommand
// Adds a given command to the history stack
//
// Parameters:
// cmd - The undo command object to add
svgedit.history.BatchCommand.prototype.addSubCommand = function(cmd) {
this.stack.push(cmd);
};
// Function: svgedit.history.BatchCommand.isEmpty
// Returns a boolean indicating whether or not the batch command is empty
svgedit.history.BatchCommand.prototype.isEmpty = function() {
return this.stack.length == 0;
};
// Class: svgedit.history.UndoManager
// Parameters:
// historyEventHandler - an object that conforms to the HistoryEventHandler interface
// (see above)
svgedit.history.UndoManager = function(historyEventHandler) {
this.handler_ = historyEventHandler || null;
this.undoStackPointer = 0;
this.undoStack = [];
// this is the stack that stores the original values, the elements and
// the attribute name for begin/finish
this.undoChangeStackPointer = -1;
this.undoableChangeStack = [];
};
// Function: svgedit.history.UndoManager.resetUndoStack
// Resets the undo stack, effectively clearing the undo/redo history
svgedit.history.UndoManager.prototype.resetUndoStack = function() {
this.undoStack = [];
this.undoStackPointer = 0;
};
// Function: svgedit.history.UndoManager.getUndoStackSize
// Returns:
// Integer with the current size of the undo history stack
svgedit.history.UndoManager.prototype.getUndoStackSize = function() {
return this.undoStackPointer;
};
// Function: svgedit.history.UndoManager.getRedoStackSize
// Returns:
// Integer with the current size of the redo history stack
svgedit.history.UndoManager.prototype.getRedoStackSize = function() {
return this.undoStack.length - this.undoStackPointer;
};
// Function: svgedit.history.UndoManager.getNextUndoCommandText
// Returns:
// String associated with the next undo command
svgedit.history.UndoManager.prototype.getNextUndoCommandText = function() {
return this.undoStackPointer > 0 ? this.undoStack[this.undoStackPointer-1].getText() : "";
};
// Function: svgedit.history.UndoManager.getNextRedoCommandText
// Returns:
// String associated with the next redo command
svgedit.history.UndoManager.prototype.getNextRedoCommandText = function() {
return this.undoStackPointer < this.undoStack.length ? this.undoStack[this.undoStackPointer].getText() : "";
};
// Function: svgedit.history.UndoManager.undo
// Performs an undo step
svgedit.history.UndoManager.prototype.undo = function() {
if (this.undoStackPointer > 0) {
var cmd = this.undoStack[--this.undoStackPointer];
cmd.unapply(this.handler_);
}
};
// Function: svgedit.history.UndoManager.redo
// Performs a redo step
svgedit.history.UndoManager.prototype.redo = function() {
if (this.undoStackPointer < this.undoStack.length && this.undoStack.length > 0) {
var cmd = this.undoStack[this.undoStackPointer++];
cmd.apply(this.handler_);
}
};
// Function: svgedit.history.UndoManager.addCommandToHistory
// Adds a command object to the undo history stack
//
// Parameters:
// cmd - The command object to add
svgedit.history.UndoManager.prototype.addCommandToHistory = function(cmd) {
// FIXME: we MUST compress consecutive text changes to the same element
// (right now each keystroke is saved as a separate command that includes the
// entire text contents of the text element)
// TODO: consider limiting the history that we store here (need to do some slicing)
// if our stack pointer is not at the end, then we have to remove
// all commands after the pointer and insert the new command
if (this.undoStackPointer < this.undoStack.length && this.undoStack.length > 0) {
this.undoStack = this.undoStack.splice(0, this.undoStackPointer);
}
this.undoStack.push(cmd);
this.undoStackPointer = this.undoStack.length;
};
// Function: svgedit.history.UndoManager.beginUndoableChange
// This function tells the canvas to remember the old values of the
// attrName attribute for each element sent in. The elements and values
// are stored on a stack, so the next call to finishUndoableChange() will
// pop the elements and old values off the stack, gets the current values
// from the DOM and uses all of these to construct the undo-able command.
//
// Parameters:
// attrName - The name of the attribute being changed
// elems - Array of DOM elements being changed
svgedit.history.UndoManager.prototype.beginUndoableChange = function(attrName, elems) {
var p = ++this.undoChangeStackPointer;
var i = elems.length;
var oldValues = new Array(i), elements = new Array(i);
while (i--) {
var elem = elems[i];
if (elem == null) continue;
elements[i] = elem;
oldValues[i] = elem.getAttribute(attrName);
}
this.undoableChangeStack[p] = {'attrName': attrName,
'oldValues': oldValues,
'elements': elements};
};
// Function: svgedit.history.UndoManager.finishUndoableChange
// This function returns a BatchCommand object which summarizes the
// change since beginUndoableChange was called. The command can then
// be added to the command history
//
// Returns:
// Batch command object with resulting changes
svgedit.history.UndoManager.prototype.finishUndoableChange = function() {
var p = this.undoChangeStackPointer--;
var changeset = this.undoableChangeStack[p];
var i = changeset['elements'].length;
var attrName = changeset['attrName'];
var batchCmd = new svgedit.history.BatchCommand("Change " + attrName);
while (i--) {
var elem = changeset['elements'][i];
if (elem == null) continue;
var changes = {};
changes[attrName] = changeset['oldValues'][i];
if (changes[attrName] != elem.getAttribute(attrName)) {
batchCmd.addSubCommand(new svgedit.history.ChangeElementCommand(elem, changes, attrName));
}
}
this.undoableChangeStack[p] = null;
return batchCmd;
};
})();