[evolution/wip/mcrha/webkit-jsc-api] e-undo-redo.js: Merge consecutive insertText undo records on word delimiter

[Milan Crha <mcrha src gnome org>]

commit 3917b4a4d55fc3659623581b18e28b62c8717f4e
Author: Milan Crha <mcrha redhat com>
Date:   Thu Oct 31 18:29:00 2019 +0100

    e-undo-redo.js: Merge consecutive insertText undo records on word delimiter

 data/webkit/e-undo-redo.js | 128 ++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 127 insertions(+), 1 deletion(-)
---
diff --git a/data/webkit/e-undo-redo.js b/data/webkit/e-undo-redo.js
index 38c03f2180..7485761b70 100644
--- a/data/webkit/e-undo-redo.js
+++ b/data/webkit/e-undo-redo.js
@@ -185,6 +185,106 @@ var EvoUndoRedo = {
                        EvoUndoRedo.stack.maybeStateChanged();
 
                        return record;
+               },
+
+               pathMatches : function(path1, path2) {
+                       if (!path1)
+                               return !path2;
+                       else if (!path2 || path1.length != path2.length)
+                               return false;
+
+                       var ii;
+
+                       for (ii = 0; ii < path1.length; ii++) {
+                               if (path1[ii] != path2[ii])
+                                       return false;
+                       }
+
+                       return true;
+               },
+
+               topInsertTextAtSamePlace : function() {
+                       if (EvoUndoRedo.stack.current != EvoUndoRedo.stack.top ||
+                           EvoUndoRedo.stack.current == EvoUndoRedo.stack.bottom) {
+                               return false;
+                       }
+
+                       var curr, prev;
+
+                       curr = EvoUndoRedo.stack.array[EvoUndoRedo.stack.current];
+                       prev = EvoUndoRedo.stack.array[EvoUndoRedo.stack.clampIndex(EvoUndoRedo.stack.current 
- 1)];
+
+                       return curr && prev &&
+                               curr.kind == EvoUndoRedo.RECORD_KIND_EVENT &&
+                               curr.opType == "insertText" &&
+                               !curr.selectionBefore.extentElem &&
+                               prev.kind == EvoUndoRedo.RECORD_KIND_EVENT &&
+                               prev.opType == "insertText" &&
+                               !prev.selectionBefore.extentElem &&
+                               curr.firstChildIndex == prev.firstChildIndex &&
+                               curr.restChildrenCount == prev.restChildrenCount &&
+                               curr.selectionBefore.baseOffset == prev.selectionAfter.baseOffset &&
+                               EvoUndoRedo.stack.pathMatches(curr.path, prev.path) &&
+                               EvoUndoRedo.stack.pathMatches(curr.selectionBefore.baseElem, 
prev.selectionAfter.baseElem);
+               },
+
+               maybeMergeInsertText : function(skipFirst) {
+                       if (EvoUndoRedo.stack.current != EvoUndoRedo.stack.top ||
+                           EvoUndoRedo.stack.current == EvoUndoRedo.stack.bottom) {
+                               return;
+                       }
+
+                       var ii, from, curr, keep = null;
+
+                       from = EvoUndoRedo.stack.current;
+                       curr = EvoUndoRedo.stack.array[from];
+
+                       if (skipFirst) {
+                               keep = curr;
+                               from = EvoUndoRedo.stack.clampIndex(from - 1);
+                               curr = EvoUndoRedo.stack.array[from];
+                       }
+
+                       if (!curr ||
+                           curr.kind != EvoUndoRedo.RECORD_KIND_EVENT ||
+                           curr.opType != "insertText" ||
+                           curr.selectionBefore.extentElem) {
+                               return;
+                       }
+
+                       for (ii = EvoUndoRedo.stack.clampIndex(from - 1);
+                            ii != EvoUndoRedo.stack.bottom;
+                            ii = EvoUndoRedo.stack.clampIndex(ii - 1)) {
+                               var prev;
+
+                               prev = EvoUndoRedo.stack.array[ii];
+
+                               if (prev.kind != EvoUndoRedo.RECORD_KIND_EVENT ||
+                                   prev.opType != "insertText" ||
+                                   prev.selectionBefore.extentElem ||
+                                   curr.firstChildIndex != prev.firstChildIndex ||
+                                   curr.restChildrenCount != prev.restChildrenCount ||
+                                   curr.selectionBefore.baseOffset != prev.selectionAfter.baseOffset ||
+                                   !EvoUndoRedo.stack.pathMatches(curr.path, prev.path) ||
+                                   !EvoUndoRedo.stack.pathMatches(curr.selectionBefore.baseElem, 
prev.selectionAfter.baseElem)) {
+                                       break;
+                               }
+
+                               prev.opType = "insertText::merged";
+                               prev.selectionAfter = curr.selectionAfter;
+                               prev.htmlAfter = curr.htmlAfter;
+
+                               curr = prev;
+                               EvoUndoRedo.stack.array[EvoUndoRedo.stack.clampIndex(ii + 1)] = keep;
+                               if (keep) {
+                                       EvoUndoRedo.stack.array[EvoUndoRedo.stack.clampIndex(ii + 2)] = null;
+                               }
+
+                               EvoUndoRedo.stack.top = ii + (keep ? 1 : 0);
+                               EvoUndoRedo.stack.current = EvoUndoRedo.stack.top;
+                       }
+
+                       EvoUndoRedo.stack.maybeStateChanged();
                }
        },
 
@@ -259,6 +359,13 @@ EvoUndoRedo.Disable = function()
        }
 }
 
+EvoUndoRedo.isWordDelimEvent = function(inputEvent)
+{
+       return inputEvent.inputType == "insertText" &&
+               inputEvent.data.length == 1 &&
+               (inputEvent.data == " " || inputEvent.data == "\t");
+}
+
 EvoUndoRedo.before_input_cb = function(inputEvent)
 {
        if (EvoUndoRedo.disabled) {
@@ -267,6 +374,9 @@ EvoUndoRedo.before_input_cb = function(inputEvent)
 
        var opType = inputEvent.inputType;
 
+       if (EvoUndoRedo.isWordDelimEvent(inputEvent))
+               opType += "::WordDelim";
+
        EvoUndoRedo.StartRecord(EvoUndoRedo.RECORD_KIND_EVENT, opType, null, null,
                EvoEditor.CLAIM_CONTENT_FLAG_SAVE_HTML | EvoEditor.CLAIM_CONTENT_FLAG_USE_PARENT_BLOCK_NODE);
 }
@@ -277,7 +387,17 @@ EvoUndoRedo.input_cb = function(inputEvent)
                return;
        }
 
-       EvoUndoRedo.StopRecord(EvoUndoRedo.RECORD_KIND_EVENT, inputEvent.inputType);
+       var opType = inputEvent.inputType;
+
+       if (EvoUndoRedo.isWordDelimEvent(inputEvent))
+               opType += "::WordDelim";
+
+       EvoUndoRedo.StopRecord(EvoUndoRedo.RECORD_KIND_EVENT, opType);
+
+       if (!EvoUndoRedo.ongoingRecordings.length && opType == "insertText" &&
+           !EvoUndoRedo.stack.topInsertTextAtSamePlace()) {
+               EvoUndoRedo.stack.maybeMergeInsertText(true);
+       }
 }
 
 EvoUndoRedo.applyRecord = function(record, isUndo, withSelection)
@@ -479,13 +599,19 @@ EvoUndoRedo.StopRecord = function(kind, opType)
        if (EvoUndoRedo.ongoingRecordings.length) {
                var parentRecord = EvoUndoRedo.ongoingRecordings[EvoUndoRedo.ongoingRecordings.length - 1];
                var records = parentRecord.records;
+
                if (!records) {
                        records = [];
                }
+
                records[records.length] = record;
                parentRecord.records = records;
        } else {
                EvoUndoRedo.stack.push(record);
+
+               if (record.kind != EvoUndoRedo.RECORD_KIND_EVENT || record.opType != "insertText") {
+                       EvoUndoRedo.stack.maybeMergeInsertText(true);
+               }
        }
 }