//行为型模式：解释器模式
//场景：四则运算

#include <iostream>
#include <string>
#include <map>
#include <stack>
#include <typeinfo>using namespace std;//*******************************************抽象表达式类***********************************
class Expression
{
public://解析公式和数值，其中var中的key是公式中的参数，value值是具体的数字//如a = 100; b = 20; c = 40virtual int interpreter(map<string, int>& var) = 0;virtual ~Expression(){};
};//变量解析器（终结符表达式）
class VarExpression : public Expression
{string key;
public:VarExpression(string key){this->key = key;}//从map中取出变量的值int interpreter(map<string, int>& var){return var[key];}~VarExpression(){cout << "~VarExpression()" << endl;}
};
//**********抽象运算符号解析器***********************
//抽象运算符号解析器
class SymbolExpression : public Expression
{
protected:Expression* left;Expression* right;
public:SymbolExpression(Expression* left, Expression* right){this -> left = left;this -> right = right;}Expression* getLeft(){return left;}Expression* getRight(){return right;}
};//加法解析器
class AddExpression : public SymbolExpression
{
public:AddExpression(Expression* left, Expression* right): SymbolExpression(left,right){}//把左右两个表达式运算的结果加起来int interpreter(map<string, int>& var){return left->interpreter(var) + right ->interpreter(var);}~AddExpression(){cout << "~AddExpression()" << endl;}
};//减法解析器
class SubExpression : public SymbolExpression
{
public:SubExpression(Expression* left, Expression* right): SymbolExpression(left,right){}//把左右两个表达式运算的结果相减int interpreter(map<string, int>& var){return left->interpreter(var) - right ->interpreter(var);}~SubExpression(){cout << "~SubExpression()" << endl;}
};//*********************************解析器封装类***************************************
//解析器封装类，这个类是根据迪米特法则进行封装，目的是让Client只与直接朋友打交道，相当于Facade
class Calculator
{
private:Expression* expression;
public://构造函数传参，并解析表达式，构建语法树Calculator(string expStr){expression = NULL;//栈，用来暂存中间结果stack<Expression*> stkExp;Expression* left  = NULL;Expression* right = NULL;/*从左到向分析表达式（如:a+b-c)，最终的语法树如下：*           -*         /   \*       +     c*     /   \*    a     b*/for(unsigned int i = 0; i< expStr.length(); i++){switch(expStr[i]){case '+':  //加法//1.先从栈中取出左操作数left = stkExp.top();stkExp.pop();//2.从表达式中取出+号后面的右操作数，并生成终结符解析对象right = new VarExpression(expStr.substr(++i,1));//3.将左右操作数相加，并把结果放入栈中stkExp.push(new AddExpression(left, right));break;case '-'://1.先从栈中取出左操作数left = stkExp.top();stkExp.pop();//2.从表达式中取出+号后面的右操作数，并生成终结符解析对象right = new VarExpression(expStr.substr(++i,1));//3.将左右操作数相减，并把结果放入栈中stkExp.push(new SubExpression(left, right));break;default://如果是变量（终结符）：如a+b+c中的a\b\c，//则直接生成对应的变量解析器对象stkExp.push(new VarExpression(expStr.substr(i,1)));}}//栈中保存的就是最终语法树的根结点（本例为SuuExpression对象）if(!stkExp.empty()){expression = stkExp.top();stkExp.pop();}}void deltree(Expression* expression){SymbolExpression* branch = dynamic_cast<SymbolExpression*>(expression);//叶子结点if (branch == NULL){delete expression;}else  //分支结点
        {//左子树deltree(branch->getLeft());//右子树deltree(branch->getRight());//结点delete expression;}}~Calculator(){deltree(expression);expression = NULL;}//开始运算int run(map<string, int>& var){return (expression == NULL) ? 0 : expression->interpreter(var);}
};
int main()
{string expStr = "a+b-c"; //为简化处理，这里必须是合法的表达式
map<string, int> var;   //相当于Interpreter模式中的Contextvar["a"] = 100;var["b"] = 20;var["c"] = 40;Calculator cal(expStr);cout <<"运算结果为：" << expStr << " = " << cal.run(var) << endl;return 0;
}
/*
运算结果为：a+b-c = 80
~VarExpression()
~VarExpression()
~AddExpression()
~VarExpression()
~SubExpression()
*/

//行为型模式：解释器模式
//场景：中文数字转阿拉伯数字
/*
1、使用Interpreter模式来将中文数字转换为数学数字的好处是可以应对中文数字的变化，
虽然可以用一很好的算法将中文转化为数字，解释器的扩展性能比较好，如果出现亿、兆的情况，
可以写出两个类（YiExpression、ZhaoExpression）来继承Expression类，而其他地方的代码都不变化。
2、思路：用单位用分解出不同的解释器.其中个位、十位、百位和千位是终结符解释器，万位是非结终符解释器，因为万以上的单位可以形成如果九百零一万之类的数字，需要进一进拆分成由结终符构成的解释器来完成任务。
3、转化：将中文数字串由低位向高位方向不断转化*/
#include <iostream>
#include <string>
#include <map>
#include <stack>
#include <list>using namespace std;//字符串上下文信息：保存没有处理的字符串信息
class Context
{
private:string statement;int data;
public:Context(string statement){this ->statement = statement;data = 0;}string& getStatement(){return  statement;}void setStatement(string statement){this -> statement = statement;}int getData(){return data;}void setData(int data){this -> data = data;}
};//抽象类：解释器
class Expression
{
protected://数据字典：保存中文数字一到九static map<string, int> table;//辅助函数，用来判判断src字符串是否以tail串结尾bool stringEndsWith(const string& src, const string& tail){if(src.size() < tail.size())return false;string tmp = src.substr(src.size() - tail.size(), tail.size());return (0==tmp.compare(0,tail.size(),tail));}
public://虚方法：中文数字到数字的转换virtual void interpret(Context& context){if(context.getStatement().length() == 0)return;map<string, int>::iterator iter = table.begin();while (iter != table.end()){string& statement = context.getStatement();string tail = iter->first + getPostfix();//从低位往高位分析（如九千三百零五，从右向左分析）if(stringEndsWith(statement,tail)){context.setData(context.getData() + iter->second * multiplier());//注意，string是ASCII编码，每个中文字符的长度为2context.setStatement(statement.substr(0, statement.length()-2 - getPostfix().length()));}if(stringEndsWith(statement,"零")){//”零“则直接跳过context.setStatement(statement.substr(0, statement.length()-2));}++iter;}}//表达式的后缀是以什么表示的（十、百...)virtual string getPostfix() = 0;//表达式的数量级virtual int multiplier() = 0;virtual ~Expression(){};
};//映射表，保存中文数字与罗马数字的映射
static map<string, int>::value_type init_table[] =
{map<string, int>::value_type("一",1),map<string, int>::value_type("二",2),map<string, int>::value_type("三",3),map<string, int>::value_type("四",4),map<string, int>::value_type("五",5),map<string, int>::value_type("六",6),map<string, int>::value_type("七",7),map<string, int>::value_type("八",8),map<string, int>::value_type("九",9)
};map<string,int> Expression::table(init_table,init_table + 9);//个位数解释器(终结符表达式)
class GeExpression : public Expression
{
public:string getPostfix(){return "";}int multiplier(){return 1;}
};//十位数解释器(终结符表达式)
class ShiExpression  : public Expression
{
public:string getPostfix(){return "十";}int multiplier(){return 10;}
};//百位数解释器(终结符表达式)
class BaiExpression  : public Expression
{
public:string getPostfix(){return "百";}int multiplier(){return 100;}
};//千位数解释器(终结符表达式)
class QianExpression : public Expression
{
public:string getPostfix(){return "千";}int multiplier(){return 1000;}
};//万位数解释器(非终结符表达式)
class WanExpression : public Expression
{
public:string getPostfix(){return "万";}int multiplier(){return 10000;}void interpret(Context& context){if(context.getStatement().length() == 0)return ;if (stringEndsWith(context.getStatement(),getPostfix())){list<Expression*> exps;exps.clear();exps.push_back(new GeExpression());exps.push_back(new ShiExpression());exps.push_back(new BaiExpression());exps.push_back(new QianExpression());int temp = context.getData();string& sm = context.getStatement();context.setData(0);//string类中每个中文长度为2.context.setStatement(sm.substr(0, sm.length()-2));list<Expression*>::iterator iter = exps.begin();while (iter != exps.end()){(*iter)->interpret(context);++iter;}context.setData(temp + multiplier()* context.getData());iter = exps.begin();while (iter != exps.end()){delete (*iter);++iter;}exps.clear();}}
};//转换器
class Convertor
{
private:Context context;string chineseNum;int result;list<Expression*> exps;void reset(){context.setStatement(chineseNum);context.setData(0);list<Expression*>::iterator iter = exps.begin();while (iter != exps.end()){delete (*iter);++iter;}exps.clear();}public:Convertor(const string chineseNum):context(chineseNum){this ->chineseNum = chineseNum;result = 0;}void convert(){reset();exps.push_back(new GeExpression());exps.push_back(new ShiExpression());exps.push_back(new BaiExpression());exps.push_back(new QianExpression());exps.push_back(new WanExpression());list<Expression*>::iterator iter = exps.begin();while (iter != exps.end()){(*iter)->interpret(context);++iter;}result = context.getData();}int getRoman(){return result;}void setChineseNum(const string& chineseNum){this ->chineseNum = chineseNum;}~Convertor(){reset();}
};int main()
{string chineseNum = "四百九十六万二千三百一十五";Convertor conv(chineseNum);conv.convert();cout << chineseNum << " -> " << conv.getRoman() << endl;chineseNum = "九千零五万六千零七十二";conv.setChineseNum(chineseNum);conv.convert();cout << chineseNum << " -> " << conv.getRoman() << endl;return 0;
}
/*输出结果：
四百九十六万二千三百一十五 -> 4962315
九千零五万六千零七十二 -> 90056072
*/

//行为型模式：解释器模式
//场景：开发一套机器人控制程序
/*说明：机器人控制程序中包含一些简单的英文控制指令，每一个指令对应一个表达式(expression)，该表达式可以是简单表达式也可以是复合表达式，每一个简单表达式由移动方向(direction)，移动方式(action)和移动距离(distance)三部分组成，其中移动方向包括上(up)、下(down)、左(left)、右(right)；移动方式包括移动(move)和快速移动(run)；移动距离为一个正整数。两个表达式之间可以通过与(and)连接，形成复合(composite)表达式。用户通过对图形化的设置界面进行操作可以创建一个机器人控制指令，机器人在收到指令
后将按照指令的设置进行移动，例如输入控制指令：up move 5，则“向上移动5个单位”；输入控
制指令：down  run 10 and left move 20，则“向下快速移动10个单位再向左移动20个单位”。
*//*文法规则expression ::= direction action distance | composite //表达式composite ::= expression 'and' expression //复合表达式direction ::= 'up' | 'down' | 'left' | 'right' //移动方向action ::= 'move' | 'run' //移动方式distance ::= an integer //移动距离
上述语言一共定义了五条文法规则，对应五个语言单位，这些语言单位可以分为两类，
终结符（也称为终结符表达式）：例如direction、action和distance，它们是语言的最小组成单位，不能再进行拆分；
非终结符（也称为非终结符表达式），例如expression和composite，它们都是一个完整的句子，包含一系列终结符或非终结符。
*///本实例对机器人控制指令的输出结果进行模拟，将英文指令翻译为中文指令，实际情况是调用不同的控制程序进行机器人的控制，
//包括对移动方向、方式和距离的控制等
#include <iostream>
#include <string>
#include <stack>
#include <vector>
#include <typeinfo>using namespace std;//
// 字符串分割
//
// -------------------------------------------------------------------------
// 函数     : Split
// 功能     : 分割STL标准字符串
// 返回值   : void
// 参数     : Container<std::basic_string<CharT> >& v 存放分割结果
// 参数     : const std::basic_string<CharT>& s 待分割字符串
// 参数     : const std::basic_string<CharT>& c 分割字符串
// -------------------------------------------------------------------------
template<typename CharT, template<typename S, typename Q = std::allocator<S> > class Container>
void Split(Container<std::basic_string<CharT> >& v, const std::basic_string<CharT>& s, const std::basic_string<CharT>& c);template<template<typename S, typename Q = std::allocator<S> > class Container>
void Split(Container<std::basic_string<char> >& v, const std::basic_string<char>& s, const std::basic_string<char>& c)
{if (0 == c.length())return;std::basic_string<char>::size_type pos1 = 0;std::basic_string<char>::size_type pos2 = 0;pos1 = 0;pos2 = s.find(c);while (std::basic_string<char>::npos != pos2){v.push_back(s.substr(pos1, pos2 - pos1));pos1 = pos2 + c.size();pos2 = s.find(c, pos1);}if (pos1 != s.length()){v.push_back(s.substr(pos1));}
}//抽象类：解释器
class AbstractExpression
{
public:virtual string interpret() = 0;virtual ~AbstractExpression(){}
};
//And解释器：非终结符表达式
class AndExpression : public AbstractExpression
{
private:AbstractExpression* left ; //And的左表达式AbstractExpression* right; //And的右表达式
public:AndExpression(AbstractExpression* left,AbstractExpression* right){this->left  = left;this->right = right;}//And表达式解释操作string interpret(){return left->interpret() + "再" + right->interpret();}AbstractExpression* getLeft(){return left;}AbstractExpression* getRight(){return right;}
};//简单句子解释器：非终结符表达式
//如：up move 5，表示“向上移动5个单位
class SentenceExpression : public AbstractExpression
{
private:AbstractExpression* direction;AbstractExpression* action;AbstractExpression* distance;
public:SentenceExpression(AbstractExpression* direction,AbstractExpression* action,AbstractExpression* distance){this->direction = direction;this->action = action;this->distance = distance;}//解释操作string interpret(){return direction->interpret() + action->interpret() + distance->interpret();}AbstractExpression* getDirection(){return direction;}AbstractExpression* getAction(){return action;}AbstractExpression* getDistance(){return distance;}
};//方向解释器：终结符表达式
class DirectionExpression : public AbstractExpression
{
private:string direction;
public:DirectionExpression(string direction){this->direction = direction;}//方向表达式的解释操作string interpret(){if(direction =="up"){return "向上";}else if(direction == "down"){return "向下";}else if(direction == "left"){return "向左";}else if(direction == "right"){return "向右";}else{return "无效指令";}}
};//动作解释器：(终结符表达式)
class ActionExpression : public AbstractExpression
{
private:string action;
public:ActionExpression(string action){this->action = action;}//动作移动表达式的解释操作string interpret(){if(action == "move"){return "移动";}else if(action == "run"){return "快速移动";}else{return "无效指令";}}
};//距离解释器：（终结符表达式）
class DistanceExpression : public AbstractExpression
{
private:string distance;
public:DistanceExpression(string distance){this->distance = distance;}string interpret(){return distance;}
};//指令处理类：工具类
class InstructionHandler
{
private:AbstractExpression* mExp;void delTree(AbstractExpression* exp)  //删除最终的生成的抽象树
    {//叶子结果bool bLeaf = typeid(*exp) ==typeid(DirectionExpression) ||typeid(*exp) ==typeid(ActionExpression) ||typeid(*exp) ==typeid(DistanceExpression);AndExpression* andExp = dynamic_cast<AndExpression*>(exp);SentenceExpression* sentenceExp = dynamic_cast<SentenceExpression*>(exp);if(bLeaf){delete exp;}else if (andExp != NULL)  //And表达式
        {AbstractExpression* left = andExp->getLeft();AbstractExpression* right = andExp->getRight();delTree(left);delTree(right);delete andExp;}else if(sentenceExp != NULL) //简单句子表达式
        {AbstractExpression* dir = sentenceExp->getDirection();AbstractExpression* act = sentenceExp->getAction();AbstractExpression* dis = sentenceExp->getDistance();delTree(dir);delTree(act);delTree(dis);delete sentenceExp;}else{}}
public:InstructionHandler():mExp(NULL){}void handle(string instruction){AbstractExpression* left = NULL;AbstractExpression* right = NULL;AbstractExpression* direction = NULL;AbstractExpression* action = NULL;AbstractExpression* distance = NULL;if (mExp!=NULL){delTree(mExp);mExp = NULL;}//声明一个栈对象用于存储抽象语法树stack<AbstractExpression*> stkExp;vector<string> words;Split(words, instruction, " "); //以空格分隔指令字符串for(unsigned int i=0; i<words.size(); i++){//本实例采用栈的方式来处理指令，如果遇到and则将其后的三个单词连成一个简单句子（Sentence）//作为"and"的右表达式，而将栈顶弹出的表达式作为"and"的左表达式，最后将新的And表达式压入栈中string dir("");string act("");string dis("");if(words[i] =="and"){//从弹出栈顶作为and的左表达式left = stkExp.top();stkExp.pop();dir = words[++i];direction = new DirectionExpression(dir);act = words[++i];action = new ActionExpression(act);dis = words[++i];distance = new DistanceExpression(dis);//组成一个简单表达式作为And的右表达式right = new SentenceExpression(direction, action, distance);//生成And表达式，并压入栈中stkExp.push(new AndExpression(left, right));}//如果不是and表达式，就从头开始进行解释，将前3个单词作为Sentence//的三个操作数，生成简单表达式解析器后压入栈中else{dir = words[i];direction = new DirectionExpression(dir);act = words[++i];action = new ActionExpression(act);dis = words[++i];distance = new DistanceExpression(dis);//组成一个简单表达式作为And的右表达式stkExp.push(new SentenceExpression(direction, action, distance));}}if(!stkExp.empty()){mExp = stkExp.top();stkExp.pop();}elsemExp = NULL;}string output(){return mExp==NULL ? "": mExp->interpret();}
};int main()
{string instruction = "up move 5 and down run 10 and left move 5";InstructionHandler handler;handler.handle(instruction);cout <<"输入指令: " <<instruction <<endl;cout <<"移动结果：" << handler.output() << endl;instruction = "right run 20 and down move 10 and left run 40 and up run 10";handler.handle(instruction);cout <<"输入指令: " <<instruction <<endl;cout <<"移动结果：" << handler.output() << endl;return 0;
}
/*输出结果：
输入指令: up move 5 and down run 10 and left move 5
移动结果：向上移动5再向下快速移动10再向左移动5
输入指令: right run 20 and down move 10 and left run 40 and up run 10
移动结果：向右快速移动20再向下移动10再向左快速移动40再向上快速移动10
*/