#pragma once
#ifndef UNDERGRADUATE_MANAGER_H
#define UNDERGRADUATE_MANAGER_H
#include <iostream>
#include <string>
#include <fstream>
#include "undergraduate.h"
using namespace std;
class UnderGraduateManager {
private:
	int top = 0;
	UnderGraduate undergraduates[100];
public:
	UnderGraduateManager();//读取文件
	int queryByNo(string sno);
	void clearStudent();
	int addStudent(UnderGraduate s);
	int modifyStudent(string sno);
	int deleteStudent(string sno);
	int queryStudent(string sno);
	void displayAll();
	void dataManage();
	void dataSave();
	void dataRead();
	~UnderGraduateManager();//写入文件
};
UnderGraduateManager::UnderGraduateManager() {
	dataRead();
}
int UnderGraduateManager::queryByNo(string sno) { // 查找，有：i， 无： -1
	for (int i = 0; i <= top; i++)
		if (undergraduates[i].getStudentNo() == sno)
			return i;
	return -1;
}
void UnderGraduateManager::clearStudent() {//停止检索最后一个元素，相当于删除元素
	top = -1;
}
int UnderGraduateManager::addStudent(UnderGraduate s) {//若不存在该元素（return -1），则元素数+1，保存至文件
	int p = queryByNo(s.getStudentNo());
	if (p == -1) {
		top++;
		undergraduates[top] = s;
		dataSave();
		return 1;
	}
	else {
		cout << "existed!" << endl;
		return 0;
	}
}
int UnderGraduateManager::modifyStudent(string sno) {//若存在该元素（return ！= -1），则修改属性，保存至文件
	int p = queryByNo(sno);
	if (p == -1) {
		cout << "Not exist!" << endl;
		return 0;
	}
	else {
		cout << "please input new detials" << endl;
		undergraduates[p].inputData();
		dataSave();
		return 1;
	}
}
int UnderGraduateManager::deleteStudent(string sno) {//删除元素，其他元素前移
	int p = queryByNo(sno);
	if (p == -1) {
		cout << "Not exist!" << endl;
		return 0;
	}
	else {
		for (int i = 0; i < top; i++)
			undergraduates[i] = undergraduates[i + 1];
		top--;
		cout << "Deleted!" << endl;
		dataSave();
		return 1;
	}
}
int UnderGraduateManager::queryStudent(string sno) {
	int p = queryByNo(sno);
	if (p == -1) {
		cout << "Not exist!" << endl;
		return 0;
	}
	else {
		cout << "exist!" << endl;
		undergraduates[p].displayDetails();
		return 1;
	}
}
void UnderGraduateManager::displayAll() {
	for (int i = 0; i <= top; i++) {
		cout << "The NO." << i << "student's info:" << endl;
		undergraduates[i].displayDetails();
	}
}
UnderGraduateManager::~UnderGraduateManager() {
	dataSave();
}
void UnderGraduateManager::dataManage() {
	int choice = 1;
	string sstudentNo;
	UnderGraduate s;
	while (choice != 0) {
		cout << "**********************************" << endl;
		cout << "\t\t undergraduate maintainace\n";
		cout << "**********************************" << endl;
		cout << "\n\t\t 1新增";
		cout << "\n\t\t 2.修改";
		cout << "\n\t\t 3.删除";
		cout << "\n\t\t 4.查找";
		cout << "\n\t\t 5.显示";
		cout << "\n\t\t 6.全部删除";
		cout << "\n\t\t 0.退出";
		cout << endl;
		cout << "**********************************" << endl;
		cout << "Please take your choice: ";
		cin >> choice;
		switch (choice) {
		case 1:
			s.inputData();
			addStudent(s);
			break;
		case 2:
			cout << " Please input student's number:";
			cin >> sstudentNo;
			modifyStudent(sstudentNo);
			break;
		case 3:
			cout << " Please input student's number:";
			cin >> sstudentNo;
			deleteStudent(sstudentNo);
			break;
		case 4:
			cout << " Please input student's number:";
			cin >> sstudentNo;
			queryStudent(sstudentNo);
			break;
		case 5:
			displayAll();
			break;
		case 6:
			clearStudent();
		default:
			break;
		}
	}
}
void UnderGraduateManager::dataSave() {
	fstream file("D:\\ProgramData\\vs\\design\\UGM.docx", ios::out);// !
	for (int i = 0; i <= top; i++) {
		file.write((char*)&undergraduates[i], sizeof(undergraduates[i]));
	}
	file.close();
}
void UnderGraduateManager::dataRead() {
	UnderGraduate s;
	top--;
	fstream file("D:\\ProgramData\\vs\\design\\UGM.docx", ios::in); // !
	while (1) {
		file.read((char*)&s, sizeof(s));
		if (!file) break;
		top++;
		undergraduates[top] = s;
	}
	file.close();
}
#endif //UNDERGRADUATE_MANAGER_H