?using System;
using System.Collections.Generic;
using System.Text;
using System.IO;
using System.Collections;


namespace 詞法分析
{
    class 詞法分析
    {
        		
		private int rnum;//行號
		private int rpos;//列號
        private static ArrayList symbolTable;
		private StreamReader br;
		private char c;
		private char bC;
		private int state;
		private String str;

//構造函數

		public 詞法分析(StreamReader br)
		{	
			symbolTable = new ArrayList();
			this.br=br;
			c=' ';
			bC=' ';
			state = 0;
			rnum=1;
			rpos=0;
			str="";
		}
//返回字符數組
		public ArrayList getSymbolTable()
		{
			c = nextChar();
			state = 0;
			analyzer();
			return symbolTable;
		}

//主體函數	
		private void analyzer()
		{
			bool isRunning=true;

			while(isRunning)
			{
				switch (state)
				{
					case 0:
					
						if(c==' ')            //空格
						{
                    
						}
						else if(c=='\t')      //tab
						{
							rpos+=3;
						}
						else if((int)c==13)   //空格
						{
                    
						}
						else if((int)c==10)   //回車
						{
							rpos = 0;
							rnum++;
						}
						else if(c=='~')       //結束符
						{
							return;
						}
						else if(c=='+')       //操作符+
						{
                            install("運算符", "+", rpos, rnum);
						} 
						else if(c=='-')       //操作符-
						{
                            install("運算符", "-", rpos, rnum);
						}
						else if(c=='/')       //操作符/
						{
							state = 1;
						}
						else if(c=='*')       //操作符*
						{
                            install("運算符", "*", rpos, rnum);
						}
						else if(c=='=')       //操作符=
						{ 
							state = 2;
						}
						else if(c=='<')       //操作符<
						{
							state = 3;
						}
						else if(c=='>')       //操作符>
						{
							state = 4;
						}
						else if(c=='!')       //操作符!
						{
							state = 5;
						}
						else if(c=='{')       //分隔符{
						{
							install("分隔符","{",rpos,rnum);
						}
						else if(c=='}')       //分隔符}
						{
							install("分隔符","}",rpos,rnum);
						}
						else if(c=='(')		  //分隔符(
						{
							install("分隔符","(",rpos,rnum);
						}
						else if(c==')')		  //分隔符)
						{
							install("分隔符",")",rpos,rnum);
						}
						else if(c==';')       //分隔符;
						{
							install("分隔符",";",rpos,rnum);
						}
						else if((int)c==65535)
						{
							isRunning=false;
						}
						else if(character(c))  //讀到了字符
						{
							bC = c;
							state = 6;
						}
						else if(digit(c))   //讀到了數字符
						{
							bC = c;
							str="";
							state = 7;
						}
						else if(c=='#')
						{
                           state=13;
						}
						else 
						{
							state=0;
							isRunning=false;
							fail(0);
						}
                       
						c = nextChar();
						break;
					case 1:
						if(c=='/')             //表示注釋后面的東西,不讀它
						{
							while((int)c!=10)
							{
								c = nextChar();
							}
							rpos=0;           //從下一行開始
							rnum++;
							c = nextChar();
							state = 0;
						}
						else 
						{
							state = 0;        // 下一個不是/, 后退一步到state=0
                            install("運算符", "/", rpos - 1, rnum);
						}

						break;
					case 2:
                
						if(c=='=')           //表示操作符==
						{
							state = 0;
                            install("運算符", "==", rpos - 1, rnum);
							c = nextChar();
						}
						else 
						{
							state = 0;
                            install("運算符", "=", rpos - 1, rnum);
						}

						break;
					case 3:
						if(c=='=')          //表示操作符<=
						{
							state = 0;
                            install("運算符", "<=", rpos - 1, rnum);
							c = nextChar();
						}
						else 
						{
							state = 0;
                            install("運算符", "<", rpos - 1, rnum);
						}
                
						break;
					case 4:
						if(c=='=')          //表示操作符>=
						{
							state = 0;
                            install("運算符", ">=", rpos - 1, rnum);
							c = nextChar();
						}
						else 
						{
							state = 0;
                            install("運算符", ">", rpos - 1, rnum);
						}

						break;
					case 5:
						if(c=='=')         // 表示操作符!=
						{
							state = 0;
							install("運算符","!=",rpos-1,rnum);
							c = nextChar();
						}
						else 
						{
							state = 0;
							isRunning=false;
							fail(1);
						}
						break;
				
		     	       
						//讀入標識符,后面是 數字符和字母才是對的
						
					case 6:                      
						String id = ""+bC;
						while(character(c)||digit(c))
						{
							id+=c;
							c = nextChar();
						}
						if(Keyword(id))
							install("保留字",id,rpos-id.Length,rnum);
						else
							install("標識符",id,rpos-id.Length,rnum);
						state = 0;
						break;
						
						//讀入數字符,后面是 數字符(循環); .(轉狀態);E(轉狀態)
						
					case 7:                         
						str+=bC; 
						while(digit(c))            
						{
							str+=c;
							c=nextChar();
						}
						if(c=='.')                  
						{
							state=8;
							c=nextChar();         
						}
						else if(c=='E')              
						{
							state=10;
							c=nextChar();
						}
						
						//需要判斷是否是  11w等
						else if(character(c))
						{
							state = 0;
							isRunning=false;
							fail(4);
                        
						}
						else                        
						{
							state = 0;
							install("常數",str,rpos-str.Length,rnum);
						}
						break;
						
						//  " ." 后面跟的字符,除了數字符其它都出錯
						
					case 8:                         
						str+='.';
						if(digit(c))
						{
							state = 9;
							str+=c;
							c=nextChar();
						}
						else
						{
							state = 0;
							isRunning=false;
							fail(2);
						}
						break;
						
						//    ".數字符" 后面字符,可以是數字符或者是E(需要加錯誤提示,當不是空格而是其他字母時候)
						
					case 9:
                
						while(digit(c))
						{
							str+=c;
							c=nextChar();
						}
						if(c=='E')
						{
							state = 10;
							c=nextChar();
						}

						//需要判斷是否是  11w 等
						else if(character(c))
						{
							state = 0;
							isRunning=false;
							fail(2);
                        
						}
						else
						{
							state = 0;
							install("常數",str,rpos-str.Length,rnum);
						}
						break;

			          
						// "E"  后面字符,  "+";"-";"數字符" 都是對的,其他都是錯的
					
					case 10:
						str+='E';
						if(c=='+'||c=='-')
						{
							state=11;
							str+=c;
							c=nextChar();
						}
						else if(digit(c))
						{
							state=12;
							str+=c;
							c=nextChar();
						}
						else
						{
							state=0;
							isRunning=false;
							fail(2);
						}
						break;
						
						//   "+" "-" 后面字符, 數字符是對的.其他都是錯的
						
					case 11:
						if(digit(c))
						{
							state=12;
							str+=c;
							c=nextChar();
						}
						else
						{
							state = 0;
							isRunning=false;
							fail(2);
						}
						break;
					
						// "E數字符"  后面字符,只有數字符是對的
					
					case 12:
						while(digit(c))
						{
							str+=c;
							c=nextChar();
						}

						 if(character(c))
						{
							state = 0;
							isRunning=false;
							fail(2);
                        
						}
						install("常數",str,rpos-str.Length,rnum);
						state=0;
						break;


					case 13: //聲明部分
 
						 id ="#";
						while(character(c))
						{
							id+=c;
							c = nextChar();
						}
						if(id=="#include"&&c=='<')
						{
										    
  					        id+=c;
							c = nextChar();
							while(character(c)||this.digit(c))
							{
							
								id+=c;
								c = nextChar();
							}
							if(c=='>')
							{
								id+=c;
							    install("文件引入",id,rpos-id.Length,rnum);
								c = nextChar();
							}
							else
							 fail(3);
                                         
						}
						else
							fail(0);
						state = 0;
						break;
					
				}  
			}
		}
 //判斷字節流中字符不合法，輸出錯誤信息
		private void fail(int i) 
		{
			string typeerror="";;
			switch(i)
			{
				case 0:
					typeerror="輸入非法字符錯誤";
					break;
				case 1:
					typeerror="操作符錯誤";
					break;

				case 2:
					typeerror="數字符錯誤";
					break;

				case 3:
					typeerror="聲明錯誤";
					break;
				case 4:
					typeerror="標識符錯誤";
					break;

			}
			
			Console.Write(typeerror+",位置<"+rnum+","+rpos+">");
		}

        //判斷下一個字符

		private char nextChar()
		{
			char t;
			rpos++;
			if(br.Peek() == -1)
			{
				br.Close();
				return '~';
			}

			t= (char) br.Read();
			return t;
		}
    //輸出字節流中每個字符的信息，包括行號，列號（主要的輸出函數）
		private void install(String tType,String aValue,int rpos,int rnum)
		{
			ArrayList tokenArray = new ArrayList();
			tokenArray.Add(tType);
            if (tType == "保留字")
                tokenArray.Add("種別碼" + "1");
            if (tType == "標識符")
                tokenArray.Add("種別碼" + "2");
            if (tType == "常數")
                tokenArray.Add("  " + "種別碼" + "3");
            if (tType == "運算符")
                tokenArray.Add("種別碼" + "4");
            if (tType == "分隔符")
                tokenArray.Add("種別碼" + "5");

            tokenArray.Add(aValue);
            tokenArray.Add("<"+rnum.ToString()+","+rpos.ToString()+">");
			symbolTable.Add(tokenArray);

			ArrayList tempArray=tokenArray;

			for(int j=0;j<tempArray.Count;j++)
			{
				Console.Write(tempArray[j].ToString()+"     ");
			}
			Console.WriteLine();

			str="";
		}
    //判斷是否是字母
		private bool character(char checkChar)
		{
			int checkInt = (int)checkChar;
			if((checkInt<=122&&checkInt>=97)||(checkInt>=65&&checkInt<=97))
			{
				return true;
			}
			return false;
		}
    //判斷是否是數字
		private bool digit(char checkChar)
		{
			int checkInt = (int)checkChar;
			if(checkInt<=57&&checkInt>=48)
			{
				return true;
			}
			return false;
		}
    //判斷是否是保留字（關鍵字）
		private bool Keyword(String checkKey)
		{
			if(checkKey.Equals("if")||checkKey.Equals("then")||
				checkKey.Equals("else")||checkKey.Equals("int")||
				checkKey.Equals("for")||checkKey.Equals("while"))
			{
				return true;
			}
			return false;
		}
    }
}