package hashmap

import (
	"474420502.top/eson/structure/compare"
)

type avlNode struct {
	children   [2]*avlNode
	hash       uint
	key, value interface{}
}

type avlTree struct {
	root         *avlNode
	lsize, rsize int
	Compare      compare.Compare
}

func avlNew(Compare compare.Compare) *avlTree {
	return &avlTree{Compare: Compare}
}

func (tree *avlTree) Clear() {
	tree.lsize, tree.rsize = 0, 0
	tree.root = nil
}

// func (tree *avlTree) Size() int {
// 	return tree.lsize + tree.rsize + 1
// }

// func (tree *avlTree) Remove(key interface{}) (interface{}, bool) {

// 	if n, ok := tree.GetNode(key); ok {

// 		tree.size--
// 		if tree.size == 0 {
// 			tree.root = nil
// 			return n.value, true
// 		}

// 		left := getHeight(n.children[0])
// 		right := getHeight(n.children[1])

// 		if left == -1 && right == -1 {
// 			p := n.parent
// 			p.children[getRelationship(n)] = nil
// 			tree.fixRemoveHeight(p)
// 			return n.value, true
// 		}

// 		var cur *avlNode
// 		if left > right {
// 			cur = n.children[0]
// 			for cur.children[1] != nil {
// 				cur = cur.children[1]
// 			}

// 			cleft := cur.children[0]
// 			cur.parent.children[getRelationship(cur)] = cleft
// 			if cleft != nil {
// 				cleft.parent = cur.parent
// 			}

// 		} else {
// 			cur = n.children[1]
// 			for cur.children[0] != nil {
// 				cur = cur.children[0]
// 			}

// 			cright := cur.children[1]
// 			cur.parent.children[getRelationship(cur)] = cright

// 			if cright != nil {
// 				cright.parent = cur.parent
// 			}
// 		}

// 		cparent := cur.parent
// 		// 修改为interface 交换
// 		n.value, cur.value = cur.value, n.value
// 		n.key, cur.key = cur.key, n.key

// 		// 考虑到刚好替换的节点是 被替换节点的孩子节点的时候, 从自身修复高度
// 		if cparent == n {
// 			tree.fixRemoveHeight(n)
// 		} else {
// 			tree.fixRemoveHeight(cparent)
// 		}

// 		return cur.value, true
// 	}

// 	return nil, false
// }

func (tree *avlTree) Get(key interface{}) (interface{}, bool) {
	n, ok := tree.GetNode(key)
	if ok {
		return n.value, true
	}
	return n, false
}

func (tree *avlTree) GetNode(key interface{}) (*avlNode, bool) {

	for n := tree.root; n != nil; {
		switch c := tree.Compare(key, n.key); c {
		case -1:
			n = n.children[0]
		case 1:
			n = n.children[1]
		case 0:
			return n, true
		default:
			panic("Get Compare only is allowed in -1, 0, 1")
		}
	}
	return nil, false
}

func (tree *avlTree) PutNode(pnode *avlNode) bool {

	pnode.children[0] = nil
	pnode.children[1] = nil
	// pnode.parent = nil

	if tree.root == nil {
		// tree.size++
		tree.root = pnode
		return true
	}

	for cur, c := tree.root, 0; ; {
		c = tree.Compare(pnode.key, cur.key)
		if c == -1 {
			if cur.children[0] == nil {
				// tree.size++
				cur.children[0] = pnode
				return true
			}
			cur = cur.children[0]
		} else if c == 1 {
			if cur.children[1] == nil {
				cur.children[1] = pnode
				return true
			}
			cur = cur.children[1]
		} else {
			cur.key = pnode.key
			cur.value = pnode.value
			return false
		}
	}
}

func (tree *avlTree) Put(key, value interface{}) bool {

	if tree.root == nil {
		tree.root = &avlNode{key: key, value: value}
		return true
	}

	for cur, c := tree.root, 0; ; {
		c = tree.Compare(key, cur.key)
		if c == -1 {
			if cur.children[0] == nil {
				cur.children[0] = &avlNode{key: key, value: value}
				return true
			}
			cur = cur.children[0]
		} else if c == 1 {
			if cur.children[1] == nil {
				cur.children[1] = &avlNode{key: key, value: value}
				return true
			}
			cur = cur.children[1]
		} else {
			cur.key = key
			cur.value = value
			return false
		}
	}
}

func (tree *avlTree) lrrotate(cur *avlNode) {

	const l = 1
	const r = 0

}

func (tree *avlTree) rlrotate(cur *avlNode) {

	const l = 0
	const r = 1

}

func (tree *avlTree) rrotate(cur *avlNode) {

	const l = 0
	const r = 1
	// 1 right 0 left
	mov := cur.children[l]

	mov.value, cur.value = cur.value, mov.value //交换值达到, 相对位移
	mov.key, cur.key = cur.key, mov.key

}

func (tree *avlTree) lrotate(cur *avlNode) {

	const l = 1
	const r = 0

	mov := cur.children[l]

	mov.value, cur.value = cur.value, mov.value //交换值达到, 相对位移
	mov.key, cur.key = cur.key, mov.key
}