svgedit/editor/history.js

612 lines
20 KiB
JavaScript

/* eslint-disable no-var */
/* globals svgedit */
/**
* Package: svedit.history
*
* Licensed under the MIT License
*
* Copyright(c) 2010 Jeff Schiller
*/
// Dependencies:
// 1) jQuery
// 2) svgtransformlist.js
// 3) svgutils.js
(function () {
'use strict';
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 = {};
/**
* An interface that all command objects must implement.
* @typedef svgedit.history.HistoryCommand
* @type {object}
* 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
* @param {Element} elem - The DOM element that was moved
* @param {Element} oldNextSibling - The element's next sibling before it was moved
* @param {Element} oldParent - The element's parent before it was moved
* @param {string} [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;
svgedit.history.MoveElementCommand.prototype.getText = function () {
return this.text;
};
/**
* Re-positions the element
* @param {handleHistoryEvent: function}
*/
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);
}
};
/**
* Positions the element back to its original location
* @param {handleHistoryEvent: function}
*/
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) {
if (window.console) {
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;
var attr;
for (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;
var attr;
for (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 = this.elem.getBBox();
var cx = bbox.x + bbox.width / 2,
cy = bbox.y + bbox.height / 2;
var rotate = ['rotate(', angle, ' ', cx, ',', cy, ')'].join('');
if (rotate !== this.elem.getAttribute('transform')) {
this.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;
var attr;
for (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 = this.elem.getBBox();
var cx = bbox.x + bbox.width / 2,
cy = bbox.y + bbox.height / 2;
var rotate = ['rotate(', angle, ' ', cx, ',', cy, ')'].join('');
if (rotate !== this.elem.getAttribute('transform')) {
this.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 i,
len = this.stack.length;
for (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);
}
var i;
for (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;
};
}());