Javascript:需要一个体面的红黑树实现

class Node {
  constructor(val) {
    this.val = val;
    this.left = null;
    this.right = null;
    this.color = 1; // 默认为红色
  }
}

class RedBlackTree {
  constructor() {
    this.root = null;
  }

  insert(val) {
    const newNode = new Node(val);
    if (this.root === null) {
      this.root = newNode;
    } else {
      this._insert(this.root, newNode);
    }
  }

  _insert(node, newNode) {
    if (newNode.val < node.val) {
      if (node.left === null) {
        node.left = newNode;
      } else {
        this._insert(node.left, newNode);
      }
    } else {
      if (node.right === null) {
        node.right = newNode;
      } else {
        this._insert(node.right, newNode);
      }
    }

    if (newNode.color === 1) {
      this._setBlack(node);
    } else {
      this._setRed(node);
    }
  }

  _setBlack(node) {
    node.color = 0;
    if (node.left !== null) {
      this._setBlack(node.left);
    }
    if (node.right !== null) {
      this._setBlack(node.right);
    }
  }

  _setRed(node) {
    node.color = 1;
    if (node.left !== null) {
      this._setRed(node.left);
    }
    if (node.right !== null) {
      this._setRed(node.right);
    }
  }

  remove(val) {
    this.root = this._remove(this.root, val);
  }

  _remove(node, val) {
    if (node === null) {
      return null;
    }

    if (node.val === val) {
      if (node.left === null) {
        return node.right;
      }
      if (node.right === null) {
        return node.left;
      }
      const pivot = node.right;
      this._rotate(node);
      this._remove(pivot, val);
    } else if (node.val < val) {
      node.right = this._remove(node.right, val);
    } else {
      node.left = this._remove(node.left, val);
    }

    return node;
  }

  _rotate(node) {
    const pivot = node.right;
    node.right = pivot.left;
    if (pivot.left !== null) {
      pivot.left.parent = node;
    }
    pivot.parent = node.parent;
    if (node.parent === null) {
      this.root = pivot;
    } else if (node === node.parent.left) {
      node.parent.left = pivot;
    } else {
      node.parent.right = pivot;
    }
    pivot.left = node;
    node.parent = pivot;
  }
}