!7

cmodule TextAssist > DynPrintLogAndEnabled {

  int moduleID = 576; // editor ID, XXX

  S lastText;

  new L<Edit> lastEdits;

  Edit proposedEdit;

  srecord Edit(int lineNr, TextEdit edit) {}

  start {

    doEvery(1.0, r check);

  }

  afterVisualize {

    addToContainer(buttons, jThreadedButton("Apply edit", r executeProposedEdit));

  }

  void check enter {

    if (!enabled) ret;

    S text = cast dm_rcall getText(moduleID);

    pcall {

      compareTexts(lastText, text);

    }

    setField(lastText := text);

  }

  void compareTexts(S lastText, S text) {

    LS linesA = lines(lastText);

    LS linesB = lines(text);

    // need same number of lines

    if (l(linesA) != l(linesB)) ret with print("Line count changed, exiting");

    L<Int> indices = differingIndices(linesA, linesB);

    if (empty(indices)) ret;

    if (l(indices) != 1) ret with print("# changed lines: " + l(indices) + ", exiting");

    int i = first(indices);

    S oldLine = linesA.get(i), newLine = linesB.get(i);

    // Make a TextEdit to see what is changed in line

    TextEdit edit = createTextEdit(oldLine, newLine);

    if (edit == null) ret with print("Line not changed? Weird.");

    print("Line " + i + ": " + edit);

    addToListWithMaxSize(lastEdits, new Edit(i, edit), 2); // keep last 2 edits

    change();

    proposeEdit(text);

  }

  void proposeEdit(S currentText) {

    L<Edit> edits = takeLast(2, lastEdits);

    if (l(edits) < 2) ret;

    int lineNr = first(edits).lineNr;

    if (second(edits).lineNr != lineNr+1) ret;

    TextEdit edit1 = first(edits).edit, edit2 = second(edits).edit;

    //if (!eq(edit1.text, edit2.text)) ret with print("Differing text: " + edit1.text + "/" + edit2.text);

    if (!eq(edit1, edit2)) ret with print("Differing edits: " + edit1 + "/" + edit2);

    S lineToEdit = get(lines(currentText), lineNr+2);

    print("Line to edit: " + lineToEdit);

    if (lineToEdit == null) ret;

    setField(proposedEdit := new Edit(lineNr+2, edit1));

    print("Proposed edit: " + proposedEdit);

    print("Would yield: " + replayTextEdit(proposedEdit.edit, lineToEdit));

  }

  void executeProposedEdit enter {

    S text = cast dm_rcall getText(moduleID);

    LS lines = lines(text);

    S newLine = replayTextEdit(proposedEdit.edit, lines.get(proposedEdit.lineNr));

    print("new line: " + newLine);

    lines.set(proposedEdit.lineNr, newLine);

    S newText = lines(lines);

    print("CHANGING TEXT");

    dm_rcall setText(moduleID, newText);

  }

}