package com.heibaiying.behavioral.interpreter;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.HashMap;

public class ZTest {
	//运行四则运算
	public static void main(String[] args) throws IOException {
		String expStr = getExpStr();
		//赋值
		HashMap<String, Integer> var = getValue(expStr);
		Calculator cal = new Calculator(expStr);
		System.out.println("运算结果为：" + expStr + "=" + cal.run(var));
	}

	//获得表达式
	public static String getExpStr() throws IOException {
		System.out.print("请输入表达式：");
		return (new BufferedReader(new InputStreamReader(System.in))).readLine();
	}

	//获得值映射
	public static HashMap<String, Integer> getValue(String exprStr) throws IOException {
		HashMap<String, Integer> map = new HashMap<>();
		//解析有几个参数要传递
		for (char ch : exprStr.toCharArray()) {
			if (ch != '+' && ch != '-') {
				//解决重复参数的问题
				if (!map.containsKey(String.valueOf(ch))) {
					String in = (new BufferedReader(new InputStreamReader(System.in))).readLine();
					map.put(String.valueOf(ch), Integer.valueOf(in));
				}
			}
		}
		return map;
	}
}
