//
// Created by PC on 25-8-9.
//

#ifndef MAXHBLT_H
#define MAXHBLT_H
#include <utility>
#include <iostream>
#include <vector>
#include "binaryTreeNode.h"
template<class T>
class maxHblt {
private:
    binaryTreeNode<std::pair<int, T>>* root;
    int bsize;
    std::vector<binaryTreeNode<std::pair<int, T>>*> data;
    static void meld(binaryTreeNode<std::pair<int, T>>* &x, binaryTreeNode<std::pair<int, T>>* &y);
public:
    maxHblt() : root(nullptr), bsize(0) {}
    maxHblt(binaryTreeNode<std::pair<int, T>>* r, int b) : root(r), bsize(b) {}
    ~maxHblt();

    void push(const T& x);
    void pop();
    void meld(maxHblt &y);
    void initialize() {}
    void display();

    T& top() {return root->element.second;}
    bool empty() {return bsize == 0;}
    int size() {return bsize;}
    void dispose(binaryTreeNode<std::pair<int, T>>* r) {
        if (r == nullptr) return;
        if (r->left != nullptr) dispose(r->left);
        if (r->right != nullptr) dispose(r->right);
        delete r;
    }
};

template<class T>
maxHblt<T>::~maxHblt() {
    dispose(root);
    root = nullptr;
    bsize = 0;
}

template<class T>
void maxHblt<T>::push(const T& x) {
    if (root == nullptr) {
        root = new binaryTreeNode<std::pair<int, T>>(std::make_pair(1, x));
        return;
    }
    auto tmp = new binaryTreeNode<std::pair<int, T>>(std::make_pair(1, x));
    meld(root, tmp);
    bsize++;
}

template<class T>
void maxHblt<T>::pop() {
    if (root == nullptr) {
        std::cerr << "Empty Error!" << std::endl;
    }
    auto left = root->left;
    auto right = root->right;
    delete root;
    root = nullptr;
    meld(left, right);
    bsize--;
}

template<class T>
void maxHblt<T>::meld(maxHblt &y) {
    meld(root, y.root);
    bsize += y.bsize;
    y.dispose(y.root);
    y.root = nullptr;
    y.bsize = 0;
}

template<class T>
void maxHblt<T>::display() {
    if (root == nullptr) {
        std::cerr << "Empty Error!" << std::endl;
        return;
    }
    data.clear();
    data.push_back(root);
    int cnt = 0;
    while (cnt < bsize) {
        if (data.at(cnt)->left != nullptr) data.push_back(data.at(cnt)->left);
        if (data.at(cnt)->right != nullptr) data.push_back(data.at(cnt)->right);
        cnt++;
    }
    for (auto x : data) {
        std::cout << "{" << x->element.first << ", " << x->element.second << "}" << ", ";
    }
    std::cout << std::endl;
}

//重要 -> 合并两个子树，把y合并进入x
//* &x，指针的引用，表示指针可以修改（传入函数）
template<class T>
void maxHblt<T>::meld(binaryTreeNode<std::pair<int, T>>*& x,
    binaryTreeNode<std::pair<int, T>>*& y) {
    if (y == nullptr) return;
    if (x == nullptr) {
        x = y;
        //一定要y = nullptr
        y = nullptr;
        return;
    }

    if (x->element.second < y->element.second) {
        std::swap(x, y);
    }

    meld(x->right, y);

    if (x->left == nullptr) {
        x->left = x->right;
        x->right = nullptr;
        x->element.first = 1;
    }
    else {
        if (x->left->element.first < x->right->element.first) {
            std::swap(x->left, x->right);
        }
        int rightNpl = (x->right ? x->right->element.first : 0);
        x->element.first = rightNpl + 1;
    }
}

#endif //MAXHBLT_H