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-rw-r--r--trunk/infrastructure/ace/www/undomodule.js258
1 files changed, 0 insertions, 258 deletions
diff --git a/trunk/infrastructure/ace/www/undomodule.js b/trunk/infrastructure/ace/www/undomodule.js
deleted file mode 100644
index b8a56f9..0000000
--- a/trunk/infrastructure/ace/www/undomodule.js
+++ /dev/null
@@ -1,258 +0,0 @@
-/**
- * Copyright 2009 Google Inc.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS-IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-
-undoModule = (function() {
- var stack = (function() {
- var stackElements = [];
- // two types of stackElements:
- // 1) { elementType: UNDOABLE_EVENT, eventType: "anything", [backset: <changeset>,]
- // [selStart: <char number>, selEnd: <char number>, selFocusAtStart: <boolean>] }
- // 2) { elementType: EXTERNAL_CHANGE, changeset: <changeset> }
- // invariant: no two consecutive EXTERNAL_CHANGEs
- var numUndoableEvents = 0;
-
- var UNDOABLE_EVENT = "undoableEvent";
- var EXTERNAL_CHANGE = "externalChange";
-
- function clearStack() {
- stackElements.length = 0;
- stackElements.push({ elementType: UNDOABLE_EVENT, eventType: "bottom" });
- numUndoableEvents = 1;
- }
- clearStack();
-
- function pushEvent(event) {
- var e = extend({}, event);
- e.elementType = UNDOABLE_EVENT;
- stackElements.push(e);
- numUndoableEvents++;
- //dmesg("pushEvent backset: "+event.backset);
- }
-
- function pushExternalChange(cs) {
- var idx = stackElements.length-1;
- if (stackElements[idx].elementType == EXTERNAL_CHANGE) {
- stackElements[idx].changeset = Changeset.compose(stackElements[idx].changeset, cs, getAPool());
- }
- else {
- stackElements.push({elementType: EXTERNAL_CHANGE, changeset: cs});
- }
- }
-
- function _exposeEvent(nthFromTop) {
- // precond: 0 <= nthFromTop < numUndoableEvents
- var targetIndex = stackElements.length - 1 - nthFromTop;
- var idx = stackElements.length - 1;
- while (idx > targetIndex || stackElements[idx].elementType == EXTERNAL_CHANGE) {
- if (stackElements[idx].elementType == EXTERNAL_CHANGE) {
- var ex = stackElements[idx];
- var un = stackElements[idx-1];
- if (un.backset) {
- var excs = ex.changeset;
- var unbs = un.backset;
- un.backset = Changeset.follow(excs, un.backset, false, getAPool());
- ex.changeset = Changeset.follow(unbs, ex.changeset, true, getAPool());
- if ((typeof un.selStart) == "number") {
- var newSel = Changeset.characterRangeFollow(excs, un.selStart, un.selEnd);
- un.selStart = newSel[0];
- un.selEnd = newSel[1];
- if (un.selStart == un.selEnd) {
- un.selFocusAtStart = false;
- }
- }
- }
- stackElements[idx-1] = ex;
- stackElements[idx] = un;
- if (idx >= 2 && stackElements[idx-2].elementType == EXTERNAL_CHANGE) {
- ex.changeset = Changeset.compose(stackElements[idx-2].changeset,
- ex.changeset, getAPool());
- stackElements.splice(idx-2, 1);
- idx--;
- }
- }
- else {
- idx--;
- }
- }
- }
-
- function getNthFromTop(n) {
- // precond: 0 <= n < numEvents()
- _exposeEvent(n);
- return stackElements[stackElements.length - 1 - n];
- }
-
- function numEvents() {
- return numUndoableEvents;
- }
-
- function popEvent() {
- // precond: numEvents() > 0
- _exposeEvent(0);
- numUndoableEvents--;
- return stackElements.pop();
- }
-
- return {numEvents:numEvents, popEvent:popEvent, pushEvent: pushEvent,
- pushExternalChange: pushExternalChange, clearStack: clearStack,
- getNthFromTop:getNthFromTop};
- })();
-
- // invariant: stack always has at least one undoable event
-
- var undoPtr = 0; // zero-index from top of stack, 0 == top
-
- function clearHistory() {
- stack.clearStack();
- undoPtr = 0;
- }
-
- function _charOccurrences(str, c) {
- var i = 0;
- var count = 0;
- while (i >= 0 && i < str.length) {
- i = str.indexOf(c, i);
- if (i >= 0) {
- count++;
- i++;
- }
- }
- return count;
- }
-
- function _opcodeOccurrences(cs, opcode) {
- return _charOccurrences(Changeset.unpack(cs).ops, opcode);
- }
-
- function _mergeChangesets(cs1, cs2) {
- if (! cs1) return cs2;
- if (! cs2) return cs1;
-
- // Rough heuristic for whether changesets should be considered one action:
- // each does exactly one insertion, no dels, and the composition does also; or
- // each does exactly one deletion, no ins, and the composition does also.
- // A little weird in that it won't merge "make bold" with "insert char"
- // but will merge "make bold and insert char" with "insert char",
- // though that isn't expected to come up.
- var plusCount1 = _opcodeOccurrences(cs1, '+');
- var plusCount2 = _opcodeOccurrences(cs2, '+');
- var minusCount1 = _opcodeOccurrences(cs1, '-');
- var minusCount2 = _opcodeOccurrences(cs2, '-');
- if (plusCount1 == 1 && plusCount2 == 1 && minusCount1 == 0 && minusCount2 == 0) {
- var merge = Changeset.compose(cs1, cs2, getAPool());
- var plusCount3 = _opcodeOccurrences(merge, '+');
- var minusCount3 = _opcodeOccurrences(merge, '-');
- if (plusCount3 == 1 && minusCount3 == 0) {
- return merge;
- }
- }
- else if (plusCount1 == 0 && plusCount2 == 0 && minusCount1 == 1 && minusCount2 == 1) {
- var merge = Changeset.compose(cs1, cs2, getAPool());
- var plusCount3 = _opcodeOccurrences(merge, '+');
- var minusCount3 = _opcodeOccurrences(merge, '-');
- if (plusCount3 == 0 && minusCount3 == 1) {
- return merge;
- }
- }
- return null;
- }
-
- function reportEvent(event) {
- var topEvent = stack.getNthFromTop(0);
-
- function applySelectionToTop() {
- if ((typeof event.selStart) == "number") {
- topEvent.selStart = event.selStart;
- topEvent.selEnd = event.selEnd;
- topEvent.selFocusAtStart = event.selFocusAtStart;
- }
- }
-
- if ((! event.backset) || Changeset.isIdentity(event.backset)) {
- applySelectionToTop();
- }
- else {
- var merged = false;
- if (topEvent.eventType == event.eventType) {
- var merge = _mergeChangesets(event.backset, topEvent.backset);
- if (merge) {
- topEvent.backset = merge;
- //dmesg("reportEvent merge: "+merge);
- applySelectionToTop();
- merged = true;
- }
- }
- if (! merged) {
- stack.pushEvent(event);
- }
- undoPtr = 0;
- }
-
- }
-
- function reportExternalChange(changeset) {
- if (changeset && ! Changeset.isIdentity(changeset)) {
- stack.pushExternalChange(changeset);
- }
- }
-
- function _getSelectionInfo(event) {
- if ((typeof event.selStart) != "number") {
- return null;
- }
- else {
- return {selStart: event.selStart, selEnd: event.selEnd,
- selFocusAtStart: event.selFocusAtStart};
- }
- }
-
- // For "undo" and "redo", the change event must be returned
- // by eventFunc and NOT reported through the normal mechanism.
- // "eventFunc" should take a changeset and an optional selection info object,
- // or can be called with no arguments to mean that no undo is possible.
- // "eventFunc" will be called exactly once.
-
- function performUndo(eventFunc) {
- if (undoPtr < stack.numEvents()-1) {
- var backsetEvent = stack.getNthFromTop(undoPtr);
- var selectionEvent = stack.getNthFromTop(undoPtr+1);
- var undoEvent = eventFunc(backsetEvent.backset, _getSelectionInfo(selectionEvent));
- stack.pushEvent(undoEvent);
- undoPtr += 2;
- }
- else eventFunc();
- }
-
- function performRedo(eventFunc) {
- if (undoPtr >= 2) {
- var backsetEvent = stack.getNthFromTop(0);
- var selectionEvent = stack.getNthFromTop(1);
- eventFunc(backsetEvent.backset, _getSelectionInfo(selectionEvent));
- stack.popEvent();
- undoPtr -= 2;
- }
- else eventFunc();
- }
-
- function getAPool() {
- return undoModule.apool;
- }
-
- return {clearHistory:clearHistory, reportEvent:reportEvent, reportExternalChange:reportExternalChange,
- performUndo:performUndo, performRedo:performRedo, enabled: true,
- apool: null}; // apool is filled in by caller
-})(); \ No newline at end of file
generated by cgit v1.2.3-1-g7c22 (git 2.25.1) at 2024-06-27 21:32:47 +0000