===== ISTEM =====
Solve the following programming task.

TASK: Text Editor with Undo and Redo

Write a class 'Editor' that holds a text document (initially an empty string) and a cursor position (initially 0), with these methods:
- type(text): inserts text at the cursor and moves the cursor to the end of the inserted text.
- moveTo(pos): moves the cursor to pos, clamped to the range 0 to the current text length.
- backspace(n): deletes up to n characters immediately before the cursor (fewer if the cursor is closer than n to the start) and moves the cursor back by the number of characters deleted.
- undo(): reverts the most recent undo step. Does nothing if there is none.
- redo(): re-applies the most recently undone step. Does nothing if there is none.
- getText(): returns the current text.
- getCursor(): returns the current cursor position.

Undo steps:
- Every call to type, and every call to backspace that deletes at least one character, is an edit. An edit normally creates a new undo step.
- Exception: a type call is added to the previous undo step, instead of creating a new one, if the method called immediately before it (not counting getText and getCursor) was also type.
- A backspace that deletes nothing (cursor already at 0) changes nothing and creates no undo step.
- Undoing a step restores the text and the cursor to exactly what they were before the step. Redoing a step restores them to exactly what they were at the end of the step.
- Every edit clears the redo history. moveTo, undo and redo never clear it.

STARTER CODE (javascript):
class Editor {
  // Write your code here
}

module.exports = { Editor };


RULES:
- Keep the function name and signature EXACTLY as given.
- Return working code only. No explanations.
- Put the code in a single ``` block.
- Try to solve it first. If you genuinely cannot, write only this single
  line instead of producing faulty code: CANNOT_SOLVE

===== HAM YANIT =====
```javascript
class Editor {
  constructor() {
    this.text = '';
    this.cursor = 0;
    this.undoStack = [];
    this.redoStack = [];
    this.lastAction = null;
  }

  type(text) {
    const beforeText = this.text;
    const beforeCursor = this.cursor;
    const afterText = this.text.slice(0, this.cursor) + text + this.text.slice(this.cursor);
    const afterCursor = this.cursor + text.length;

    if (this.lastAction === 'type' && this.undoStack.length > 0) {
      this.undoStack[this.undoStack.length - 1].afterText = afterText;
      this.undoStack[this.undoStack.length - 1].afterCursor = afterCursor;
    } else {
      this.undoStack.push({
        beforeText,
        beforeCursor,
        afterText,
        afterCursor
      });
    }

    this.text = afterText;
    this.cursor = afterCursor;
    this.redoStack = [];
    this.lastAction = 'type';
  }

  moveTo(pos) {
    this.cursor = Math.max(0, Math.min(pos, this.text.length));
    this.lastAction = 'moveTo';
  }

  backspace(n) {
    const k = Math.min(n, this.cursor);
    if (k > 0) {
      const beforeText = this.text;
      const beforeCursor = this.cursor;
      const afterText = this.text.slice(0, this.cursor - k) + this.text.slice(this.cursor);
      const afterCursor = this.cursor - k;

      this.undoStack.push({
        beforeText,
        beforeCursor,
        afterText,
        afterCursor
      });

      this.text = afterText;
      this.cursor = afterCursor;
      this.redoStack = [];
    }
    this.lastAction = 'backspace';
  }

  undo() {
    this.lastAction = 'undo';
    if (this.undoStack.length > 0) {
      const step = this.undoStack.pop();
      this.text = step.beforeText;
      this.cursor = step.beforeCursor;
      this.redoStack.push(step);
    }
  }

  redo() {
    this.lastAction = 'redo';
    if (this.redoStack.length > 0) {
      const step = this.redoStack.pop();
      this.text = step.afterText;
      this.cursor = step.afterCursor;
      this.undoStack.push(step);
    }
  }

  getText() {
    return this.text;
  }

  getCursor() {
    return this.cursor;
  }
}

module.exports = { Editor };
```