# -*- coding: utf-8 -*-
# @Time    : 2018/3/28 20:37
# @Author  : Lv Zhangrun
# @Site    : 
# @File    : MidToAfter.py
# @Software: PyCharm
import Stack


class MidToAfter:
    def __init__(self):
        self.listOperators = ["+", "-", "×", "÷", "(", ")", "="]
        self.dictOperators = {"+": 0, "-": 0, "×": 1, "÷": 1}

    def toAfterExpression(self, expression):
        stackOperator = Stack.Stack()
        afterExpression = []
        listTemp = []
        expression = expression + "="
        for element in expression:
            if element not in self.listOperators:
                listTemp.append(element)
            elif element == "=":
                if len(listTemp)!=0:
                    strTemp=""
                    for i in range(0, len(listTemp)):
                        strTemp=strTemp+listTemp.pop(0)
                    afterExpression.append(strTemp)
            else:
                if len(listTemp)!=0:
                    strTemp=""
                    for i in range(0, len(listTemp)):
                        strTemp=strTemp+listTemp.pop(0)
                    afterExpression.append(strTemp)
                if stackOperator.isEmpty() or element == "(":
                    stackOperator.push(element)
                elif element != "(" and element != ")":
                    if stackOperator.peek() != "(" and self.dictOperators[element] > self.dictOperators[
                        stackOperator.peek()]:
                        stackOperator.push(element)
                    else:
                        while True:
                            if stackOperator.peek() == "(":
                                stackOperator.push(element)
                                break
                            elif self.dictOperators[element] < self.dictOperators[stackOperator.peek()]:
                                while not stackOperator.isEmpty() and True:
                                    strOperator = stackOperator.peek()
                                    if strOperator == "(" or self.dictOperators[strOperator] < self.dictOperators[
                                        element]:
                                        break
                                    else:
                                        stackOperator.pop()
                                        afterExpression.append(strOperator)
                            else:
                                afterExpression.append(stackOperator.pop())
                            if stackOperator.isEmpty():
                                stackOperator.push(element)
                                break
                elif element == ")":
                    while True:
                        if stackOperator.peek() != "(":
                            afterExpression.append(stackOperator.pop())
                        else:
                            stackOperator.pop()
                            break
                else:
                    stackOperator.push(element)
        if not stackOperator.isEmpty():
            while not stackOperator.isEmpty():
                afterExpression.append(stackOperator.pop())
        return afterExpression