/*擴充了++a,--a,a++,a--,+=,-=,else語句，error錯誤說明*/
#include<stdio.h>
#include<stdlib.h>
#include"pl0.h"
#include"string.h"
/*解釋執行時使用的棧*/
#define stacksize 500

int main()
{   
	bool nxtlev[symnum];
    system("cls");
	printf("Input 1.txt to text 'else'\n");
	printf("Input 2.txt to test '+= & -='\n");
	printf("Input 3.txt to text '++'&'--'\n");
	printf("Input 4.txt to text 'Error'\n");
	printf("Input pl/0 file ?");
	scanf("%s",fname);                                     /*輸入文件名*/
	fin=fopen(fname,"r");
	if(fin)
	{
		printf("List object code ?(Y/N)");                /*是否輸出虛擬機代碼*/
		scanf("%s",fname);
		listswitch=(fname[0]=='y'||fname[0]=='Y');
		printf("List symbol table ? (Y/N)");             /*是否輸出名字表*/
		scanf("%s",fname);
		tableswitch=(fname[0]=='y'||fname[0]=='Y');
		fa1=fopen("fa1.tmp","w");
		fprintf(fa1,"Iput pl/0 file ?  ");
		fprintf(fa1,"%s\n", fname);
		init();                                          /*初始化*/
		err=0;
		cc=cx=ll=0;
		ch=' ';
		if(-1!=getsym())
		{
			fa=fopen("fa.tmp","w");
			fas=fopen("fas.tmp","w");
			addset(nxtlev,declbegsys,statbegsys,symnum);
			nxtlev[period]=true;    
			if(-1==block(0,0,nxtlev))			/*調用編譯程序*/
			{
				fclose(fa);
				fclose(fa1);
				fclose(fas);
				fclose(fin);
				printf("\n");
				return 0;
			}
			fclose(fa);
			fclose(fa1);
			fclose(fas);
			if(sym!=period)
			{
				error(9);
			}
			if(err==0)
			{
				fa2=fopen("fa2.tmp", "w");
				interpret();
				fclose(fa2);
			}
			else
			{
				printf("Errors in pl/0 program");
			}
		}
		fclose(fin);
	}
	else
	{
		printf("Can't open file! \n");
	}
	 printf("\n");
     return 0;
		
}
/*
*初始化
*/
void init()
{
	int i;
	for(i=0;i<=255;i++)
	{
		ssym[i]=nul;
	}
	ssym['+']=plus;        /* char 的ASCI 作為數組下標*/
	ssym['-']=minus;
	ssym['*']=times;
	ssym['/']=slash;
	ssym['(']=lparen;
	ssym[')']=rparen;
	ssym['=']=eql;
	ssym[',']=comma;
	ssym['.']=period;
	//ssym['#']=neq;
	ssym[';']=semicolon;
	/*設置保留字名字,按照字母順序,便于折半查找*/
	strcpy(&(word[0][0]),"begin");
	strcpy(&(word[1][0]),"call");
	strcpy(&(word[2][0]),"const");
	strcpy(&(word[3][0]),"do");
    strcpy(&(word[5][0]),"else");        //擴
	strcpy(&(word[6][0]),"end");
	strcpy(&(word[8][0]),"if");
	strcpy(&(word[9][0]),"odd");
	strcpy(&(word[10][0]),"procedure");
	strcpy(&(word[11][0]),"read");
	strcpy(&(word[13][0]),"then");
	strcpy(&(word[14][0]),"to");
	strcpy(&(word[15][0]),"var");
	strcpy(&(word[16][0]),"while");
	strcpy(&(word[17][0]),"write");
	/*設置保留字符號*/
	wsym[0]=beginsym;
	wsym[1]=callsym;
	wsym[2]=constsym;
	wsym[3]=dosym;
	wsym[5]=elsesym; /* add else*/
	wsym[6]=endsym;
	wsym[8]=ifsym;
	wsym[9]=oddsym;
	wsym[10]=procsym;
	wsym[11]=readsym;
	wsym[13]=thensym;
	wsym[14]=tosym; /*add tosym*/
	wsym[15]=varsym;
	wsym[16]=whilesym;
	wsym[17]=writesym;

	/*設置指令名稱*/
	strcpy(&(mnemonic[lit][0]),"lit");
	strcpy(&(mnemonic[opr][0]),"opr");
	strcpy(&(mnemonic[lod][0]),"lod");
	strcpy(&(mnemonic[sto][0]),"sto");
	strcpy(&(mnemonic[cal][0]),"cal");
	strcpy(&(mnemonic[inte][0]),"int");
	strcpy(&(mnemonic[jmp][0]),"jmp");
	strcpy(&(mnemonic[jpc][0]),"jpc");

	/*設置符號集*/
	for(i=0;i<symnum;i++)
	{
		declbegsys[i]=false;
		statbegsys[i]=false;
		facbegsys[i]=false;
	}

	/*設置聲明開始符號集*/
	declbegsys[constsym]=true;
	declbegsys[varsym]=true;
	declbegsys[procsym]=true;
	/*設置語句開始符號集*/
	statbegsys[beginsym]=true;
	statbegsys[callsym]=true;
	statbegsys[ifsym]=true;
	statbegsys[whilesym]=true;
	/*設置因子開始符號集*/
	facbegsys[ident]=true;
	facbegsys[number]=true;
	facbegsys[lparen]=true;
	facbegsys[plusone]=true;  // 添加前自加和前自減運算
	facbegsys[minusone]=true;
}
 /*
  *用數組實現集合的集合運算
  */
int inset(int e,bool* s)
{
    return s[e];
}
int addset(bool* sr,bool* s1,bool* s2,int n)
{
    int i;
    for(i=0;i<n;i++)
    {
       sr[i]=s1[i]||s2[i];  
    }
    return 0;
}
int subset(bool* sr,bool* s1,bool* s2,int n)
{
    int i;
    for(i=0;i<n;i++)
    {
       sr[i]=s1[i]&&(!s2[i]);
    }
    return 0; 
}
int mulset(bool* sr,bool* s1,bool* s2,int n)
{
    int i;
    for(i=0;i<n;i++)
    {
       sr[i]=s1[i]&&s2[i];  
    } 
    return 0;
}
/*
 *出錯處理，打印出錯位置和錯誤編碼
 */
void error(int n)
 
{
	char space[81];
	memset(space,32,81); 
	space[cc-1]=0;//出錯時當前符號已經讀完，所以cc-1
	printf("****%s!%d\n",space,n);
	switch(n)
	{
	case 1:
	  printf("常數說明中的“=”寫成“：=”\n");
	  break;
	case 2:
	  printf("常數說明中的“=”后應是數字\n");
	  break;
    case 3:
	  printf("常數說明中的標識符應是“=”\n");
	  break;
    case 4:
	  printf("const,var,procedure后應為標識符\n");
	  break;
    case 5:
	  printf("漏掉了“，”或“；”\n");
	  break;
    case 6:
	  printf("過程說明后的符號不正確\n");
	  break;
	case 7:
	  printf("應是語句開始符\n");
	  break;
	case 8:
	  printf("程序體內語句部分的后跟符不正確\n");
	  break;
	case 9:
	  printf("程序結尾丟掉了“.”\n");
	  break;
	case 10:
	  printf("語句之間漏掉了“；”\n");
	  break;
	case 11:
	  printf("標識符未說明\n");
	  break;
	case 12:
	  printf("賦值語句中，賦值號左部標識符屬性應是變量\n");
	  break;
    case 13:
	  printf("賦值語句標識符后應是賦值號“：=”\n");
	  break;
    case 14:
	  printf("call后應為標識符\n");
	  break;
    case 15:
	  printf("call后標識符屬性應為過程\n");
	  break;
    case 16:
	  printf("常數說明中的“=”寫成“：=”\n");
	  break;
    case 17:
	  printf("丟了“end”或“；”\n");
	  break;
    case 18:
	  printf("while型循環語句中丟了do\n");
	  break;
    case 19:
	  printf("語句后的符號不正確\n");
	  break;
    case 20:
	  printf("應為關系運算符\n");
	  break;
    case 21:
	  printf("表達式內標識符屬性不能是過程\n");
	  break;
    case 22:
	  printf("表達式中漏掉“）”\n");
	  break;
    case 23:
	  printf("因子后的非法符號\n");
	  break;
    case 24:
 	  printf("表達式的開始符不能是此符號\n");
	  break;
    case 31:
	  printf("數越界\n");
	  break;
    case 32:
	  printf("read語句括號中的標識符不是變量\n");
	  break;
	}
	err++;
}
/*
 *  漏掉空格，讀取一個字符
 *
 *  每次讀一行，存入line緩沖區，line被getsym取空后再讀一行
 *
 *  被函數getsym調用
 */
int getch()
{
	if(cc==ll)
    {
		if(feof(fin))
		{
			printf("program incomplete");
			return -1;
		}
		ll=0;
		cc=0;
		printf("%d ",cx );
		fprintf(fa1,"%d ",cx);
		ch=' ';
		while(ch!=10)
		{
			//fscanf(fin,"%c",&ch)
            if(EOF==fscanf(fin,"%c",&ch))
			{
				line[ll]=0;
				break;
			}
			printf("%c",ch);
			fprintf(fa1,"%c",ch);
			line[ll]=ch;
			ll++;
		}
		printf("\n");
		fprintf(fa1,"\n");
	}
	ch=line[cc];
	cc++;
	return 0;
}
 /*詞法分析，獲取一個符號
 */

int getsym()
{
	int i,j,k;
	while( ch==' '||ch==10||ch==9)
	{
		getchdo;  /* 宏定義 getch*/
	}
	if(ch>='a'&&ch<='z')
	{ 
		k=0;
		do{
			if(k<al)
			{ 
				a[k]=ch;    /*字符數組a為臨時符號*/
				k++;
			}
			getchdo; 
		}while(ch>='a'&&ch<='z'||ch>='0'&&ch<='9');
		a[k]=0;
		strcpy(id,a);
		i=0;
		j=norw-1;
		do{                            /*折半查找保留字表*/
			k=(i+j)/2;
			if(strcmp(id,word[k])<=0)
			{
				j=k-1;
			}
			if(strcmp(id,word[k])>=0)
			{
				i=k+1;
			}

		}while(i<=j);
		if(i-1>j)      /* 找到，當前單詞為保留字*/
		{
			sym=wsym[k];
		}
		else           /* 沒找到，為用戶定義的標識符*/
		{
			sym=ident;
		}
	}
	else
	{
		if(ch>='0'&&ch<='9')
		{
			k=0;
			num=0;
			sym=number;
			do{
				num=10*num+ch-'0';
				k++;
				getchdo;
			}while(ch>='0'&&ch<='9'); /*獲取數字的值*/
			k--;
			if(k>nmax)
			{
				error(30);
			}
		}
		else
		{
			if(ch==':')             /*檢測賦值符號*/
			{
				getchdo;
				if(ch=='=')
				{
					sym=becomes;    //becomes為:=
					getchdo;
				}
				else
				{
					sym=nul;            /*不能識別的符號*/
				}
			}
			else
			{
				if(ch=='<')         /*檢測小于或小于等于符號*/
				{
					getchdo;
					if(ch=='=')
					{
						sym=leq;        //leq為<=
						getchdo;
					}
					else if(ch=='>')      //add neq 
					{
					    sym=neq;         //neq為<>
						getchdo;
					}
					else
					{ 
						sym=lss;       //lss為<
					}
				}
				else// else 11 begin
				{
					if(ch=='>')          /*檢測大于或大于等于符號*/
					{
						getchdo;
						if(ch=='=')        
						{
							sym=geq;       //geq為>=
							getchdo;
						}
						else
						{
						    sym=gtr;           //gtr為>
						}
					}
                   
                    else
					{
					 if(ch=='+')          /*檢測+,+=,++符號*/
					 {
						  getchdo;
						  if(ch=='=')
						  {
							  sym=pluseq;      //pluseq為+=
							  getchdo;
						  }
						  else if(ch=='+')
						  {
							  sym=plusone;     //plusone為++
							  getchdo;
						  }
						  else 
						  {  
							  sym=plus;        //plus為+
						  }
					 }
				     else
					 {
					    if(ch=='-')          /*檢測-,-=,--符號*/
						{
						   getchdo;
						   if(ch=='=')
						   {
							   sym=minuseq;        //minuseq為-=
							   getchdo;
						   }
						   else if(ch=='-')
						   {
							   sym=minusone;       //minusone為--
							   getchdo;
						   }
						   else 
						   {  
							   sym=minus;     //minus為-
						   }
						}
				  else
				  {
						sym=ssym[ch];/* 當符號不滿足上述條件時，全部按照單字符號處理 包括“+”等*/
						//getchdo;
						//richard
						if(sym!=period)  /*檢測是否為程序終結*/
						{
							getchdo;
						}
						//end richard
				  }
					  }

					}
			
				}//else 11 end
			}
		}
	}
	return 0;
}
/*
*生成虛擬機代碼
*
*x:instruction.f;
*y:instruction.l;
*z:instruction.a;
*/
int gen(enum fct x,int y,int z)
{
	if(cx>=cxmax)
	{
		printf("Program too long"); /*程序過長*/
		return -1;
	}
	code[cx].f=x;
	code[cx].l=y;
	code[cx].a=z;
	cx++;
	return 0;
}