//#include "stdafx.h"
#include "stdio.h"
#include "ctype.h"
#include "string.h"

#define wordlen 40 /*單詞最大長(zhǎng)度*/
/*保留字?jǐn)?shù)量*/
#define keywordSum 6 
char *keyword[keywordSum]={"else","if","int","return","void","while"};

/*純單分界符*/
char singleword[11]="+-*(){};,:";

/*雙分界符*/
char doubleword[5]="<>=!";


char ScanInFile[100];      /*待分析的源程序文件*/
char ScanOutFile[100];      /*詞法分析后的輸出文件*/

FILE *fin,*fout;         /*輸入輸出文件的指針*/

int LoadCodeFile()
{
    /* 打開(kāi)待分析的 源代碼文件*/
    
    printf("請(qǐng)輸入源程序文件名：");
    scanf("%s",ScanInFile);
    if((fin=fopen(ScanInFile,"r"))==NULL)
    {
        printf("\n找不到文件：%s\n文件打開(kāi)失敗!\n");
        return 0;
    }
    else
    return 1;
}

int CreatWordFile()
{
    /*創(chuàng)建詞法分析后結(jié)果的輸出文件*/
    int len=0;
    int i=0;
	/*？？將原程序文件拷貝到輸出文件(當(dāng)前為空)？*/
    strcpy(ScanOutFile,ScanInFile);
    while(ScanOutFile[i++]!='.');
    ScanOutFile[i+1]='s';
    ScanOutFile[i+2]='c';
    ScanOutFile[i+3]='n';
    ScanOutFile[i+4]='\0';
    if((fout=fopen(ScanOutFile,"w"))==NULL)
    {
        /*文件創(chuàng)建失敗*/
        return 0;
    }
    else
        return 1;

}

/*詞法分析程序*/
int TScan()
{

    char ch,token[wordlen]; /*ch 為每次讀入的字符，token 為識(shí)別出來(lái)的單詞*/

    char ch1; /*處理注釋時(shí) 用的臨時(shí)變量*/

    int err=0;              /* 設(shè)置錯(cuò)誤代碼為 0, 表示沒(méi)有錯(cuò)誤 */
    int j,n;                /*臨時(shí)變量，控制組合單詞時(shí)的數(shù)組下標(biāo)*/


    if(LoadCodeFile()==0)
        return 1;          /*源代碼文件讀取失敗*/
    if(CreatWordFile()==0)
        return 2;          /*文件創(chuàng)建失敗*/

    /*fin輸入文件的指針,?getc()函數(shù)*/
	ch=getc(fin);
    while(ch!=EOF)
    {
        while(ch==' '||ch=='\n'||ch=='\t')
        {
            ch=getc(fin);
        }
        if(isalpha(ch))
        {
            /*輸入的是字母，進(jìn)行 標(biāo)示符 處理*/
            token[0]=ch;
            j=0;
            while(isalnum(ch))
            {
                token[j++]=ch;
                ch=getc(fin);
            }/*如果是字母數(shù)字則組合，否則結(jié)束*/
            token[j]='\0';
            /*查找保留字*/
            n=0;
            while((n<keywordSum) && strcmp(token,keyword[n]))
                n++;
            if(n>=keywordSum)
            {
                /*輸出標(biāo)示符*/
                fprintf(fout,"%s\t%s\n","ID",token);
                printf("%s\t%s\n","ID",token);
            }
            else
            {
                /*輸出保留字*/
                fprintf(fout,"%s\t%s\n","keyword",token);
                printf("%s\t%s\n","keyword",token);
            }
        }
        else if(isdigit(ch))
        {
            /*輸入的是數(shù)字，進(jìn)行 數(shù)字處理*/
            token[0]=ch;
            j=1;
            ch=getc(fin);/*讀下一字符*/
            while(isdigit(ch))
            {/*如果是數(shù)字則整合數(shù)字*/
                token[j++]=ch;
                ch=getc(fin);
            }
            token[j]='\0';/*整數(shù)整合結(jié)束*/
            fprintf(fout,"%s\t%s\n","NUM",token);
            printf("%s\t%s\n","NUM",token);
        }
        else if(strchr(singleword,ch)>0)
        {
            /*輸入的是單分界符*/
            token[0]=ch;
            token[1]='\0';
            ch=getc(fin);
            fprintf(fout,"%s\t%s\n","single",token);
            printf("%s\t%s\n","single",token);
        }
        else if(strchr(doubleword,ch)>0)
        {
            /*輸入的是雙分界符*/
            token[0]=ch;
            ch=getc(fin);
            if(ch=='=')  /*如果是 = 則組合雙分界符*/
            {
                token[1]=ch;token[2]='\0';
                ch=getc(fin);
            }
            else
            {
                token[1]='\0';
            }
            fprintf(fout,"%s\t%s\n","double",token);
            printf("%s\t%s\n","double",token);
        }
        else if(ch=='/')
        {
            /*注釋處理*/
            ch=getc(fin);
            if(ch=='*')
            {
                ch1=getc(fin);
                do
                {
                    ch=ch1;
                    ch1=getc(fin);
                }while((ch!='*'||ch1!='/')&&ch1!=EOF);
                ch=getc(fin);
            }
            else
            {
                token[0]='/';
                token[1]='\0';
                fprintf(fout,"%s\t%s\n",token,token);  /*輸出單詞分界符*/
                printf("%s\t%s\n",token,token);
            }
        }
        else
        {
            /*無(wú)法識(shí)別的字符 */
            token[0]=ch;
            token[1]='\0';
            ch=getc(fin);
            err=3;
            fprintf(fout,"%s\t%s\n","ERROR",token);  /*輸出錯(cuò)誤符號(hào)*/
            printf("%s\t%s\n","ERROR",token);
        }
    }
    return err;
}

void main()
{
    int e=0;
    e=TScan();
    if(e>0)printf("編譯錯(cuò)誤！");
    else
        printf("詞法分析成功！");

}