// BST.cpp : This file contains the 'main' function. Program execution begins and ends there.
//

#include "pch.h"
#include <iostream>
#include <string>
#include <fstream>
#include <sstream>
#include <iterator>

using namespace std;

class EmployeeInfo {
	int ID;
	string name;

public:
	EmployeeInfo(int ID, string name) {
		this->ID = ID;
		this->name = name;
	}

	int getId() {
		return ID;
	}

	string getName() {
		return name;
	}

	friend bool operator<= (const EmployeeInfo &e1, const EmployeeInfo &e2);
	friend bool operator> (const EmployeeInfo &e1, const EmployeeInfo &e2);
};

bool operator<= (const EmployeeInfo &e1, const EmployeeInfo &e2) {
	return e1.ID <= e2.ID;
}

bool operator> (const EmployeeInfo &e1, const EmployeeInfo &e2) {
	return e1.ID > e2.ID;
}

class BSTNode {
	BSTNode* left;
	BSTNode* right;
	EmployeeInfo* info;

public:
	BSTNode(EmployeeInfo* info) {
		this->info = info;
		left = NULL;
		right = NULL;
	}

	EmployeeInfo* getInfo() {
		return info;
	}

	BSTNode* getLeft() {
		return left;
	}

	BSTNode* getRight() {
		return right;
	}

	void setLeft(BSTNode* node) {
		this->left = node;
	}

	void setRight(BSTNode* node) {
		this->right = node;
	}

};

class BST {
	BSTNode* root;

public:
	BST() {
		root = NULL;
	}

	void addNode(BSTNode* node) {
		if (root == NULL) {
			root = node;
		}
		else {
			BSTNode* cur = root;
			while (cur != NULL && ((*node).getInfo() <= (*cur).getInfo() || (*node).getInfo() > (*cur).getInfo())) {
				if ((*node).getInfo() <= (*cur).getInfo()) {
					//cout << "going left" << endl;
					BSTNode* check = (*cur).getLeft();
					if (check == NULL) {
						(*cur).setLeft(node);
					}
					cur = check;
				}
				else {
					BSTNode* check = (*cur).getRight();
					if (check == NULL) {
						(*cur).setRight(node);
					}
					cur = check;
				}
			}
		}
	}

	string findById(int ID) {
		if (root == NULL) {
			return "Employee: " + to_string(ID) + " was NOT found because the BST is empty.";
		}

		BSTNode* cur = root;
		while (cur != NULL) {
			EmployeeInfo curInfo = (*(*cur).getInfo());
			if (curInfo.getId() == ID) {
				return "Employee: " + to_string(ID) + " is " + curInfo.getName();
			}
			else if (ID < curInfo.getId()) {
				cur = (*cur).getLeft();
			}
			else {
				cur = (*cur).getRight();
			}
		}

		return "Employee: " + to_string(ID) + " was NOT found in the BST.";
	}

	BSTNode* getRoot() {
		return root;
	}
};

void help() {
	cout << "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" << endl;
	cout << "|| Commands:                                                      ||" << endl;
	cout << "||                                                                ||" << endl;
	cout << "|| '[ID number]'                                                  ||" << endl;
	cout << "|| - Searches for the ID in the BST                               ||" << endl;
	cout << "|| 'help'                                                         ||" << endl;
	cout << "|| - Show this help menu                                          ||" << endl;
	cout << "|| 'exit'                                                         ||" << endl;
	cout << "|| - Exit the program                                             ||" << endl;
	cout << "~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~" << endl;
};

void run() {
	BST bst = BST();

	ifstream inFile;
	inFile.open("C:/users/user/desktop/employees.txt");

	if (!inFile) {
		cerr << "Unable to open file employees.txt";
		exit(1);   // call system to stop
	}

	string line;
	int num = 0;

	while (getline(inFile, line)) {
		istringstream iss(line);
		int id;
		string firstName, lastName;
		while (iss >> id >> firstName >> lastName) {
			//cout << to_string(id) + " " + firstName + " " + lastName << endl;
			EmployeeInfo* e = new EmployeeInfo(id, firstName + " " + lastName);
			BSTNode* n = new BSTNode(e);
			bst.addNode(n);
		}
	}

	string input;
	while (true) {
		cout << "Please enter an ID to search for, or type help or exit:" << endl;
		getline(cin, input);
		if (input == "exit") {
			return;
		}
		else if (input == "help") {
			help();
		}
		else {
			cout << bst.findById(stoi(input)) << endl;
		}
	}
};

int main()
{
	cout << "====================================================================" << endl;
	cout << "|| Welcome to my Employee Tree!                                   ||" << endl;
	cout << "====================================================================" << endl;
	run();
}

// Run program: Ctrl + F5 or Debug > Start Without Debugging menu
// Debug program: F5 or Debug > Start Debugging menu

// Tips for Getting Started:
//   1. Use the Solution Explorer window to add/manage files
//   2. Use the Team Explorer window to connect to source control
//   3. Use the Output window to see build output and other messages
//   4. Use the Error List window to view errors
//   5. Go to Project > Add New Item to create new code files, or Project > Add Existing Item to add existing code files to the project
//   6. In the future, to open this project again, go to File > Open > Project and select the .sln file