/*
 * Copyright 2021 ByteDance 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.
 */

package ast

type Pair struct {
    Key   string
    Value Node
}

type Iterator struct {
    i int
    p *Node
}

func (self *Iterator) Pos() int {
    return self.i
}

func (self *Iterator) Len() int {
    return self.p.len()
}

func (self *Iterator) HasNext() bool {
    return self.i < self.p.len() && self.p.Valid()
}

type ListIterator struct {
    Iterator
}

type ObjectIterator struct {
    Iterator
}

func (self *ListIterator) Next(v *Node) bool {
    if !self.HasNext() {
        return false
    } else {
        *v, self.i = *self.p.nodeAt(self.i), self.i + 1
        return true
    }
}

func (self *ObjectIterator) Next(p *Pair) bool {
    if !self.HasNext() {
        return false
    } else {
        *p, self.i = *self.p.pairAt(self.i), self.i + 1
        return true
    }
}