/* To compile, save this code as wbz2jpg.c */
/* Then run the command: gcc wbz2jpg.c -o wbz2jpg  */

/* A program to convert .wbz files from webshots.com */
/* to .jpg files by stripping excess bytes before  */
/* Jpeg Header and bytes for thumbnail image. */
/* */
/* The first format has the text Adobe in the file twice. */
/* A thumbnail is in between, which gets stripped. The */
/* The second type has encrypted header and so I decrypt */
/* with one of two keys. the first 100 bytes after WWBB0000 */
/* or WWBB1111 are replaced by the next 100 bytes which */
/* need to be decrypted first */
/* then the original 2nd 100 bytes then the rest of file. */
/* By Gyrf on 22 March 2001 */

#include <stdio.h>
#define ADOBE "Adobe"
#define ALGO1 "WWBB0000"
#define ALGO2 "WWBB1111"
#define HDR1 0xFF
#define HDR2 0xD8

int main (int argc,char *argv[])
{
	FILE *fp1, *fp2;
	char *infile, *outfile;
	char isalgo1[9];
	char isadobe[6];
	int letter,flag=0,flag1=0,ishdr1=0,ishdr2=0;
	int verwb=0,cnt=0,cnt1=0,A[100],B[100],counter=0;
	int magicvalue=0,C[100];
	if(argc >= 3)
        {
                infile = argv[1];                
                outfile = argv[2];
        }
        else
        {
	printf("Usage: wbz2 inputfile.wbz ouputfile.jpg\n");
        exit (1);
	}
	if((fp1 =fopen(infile,"r")) == NULL)
		{
			printf("Can't open infile %s\n",infile);
			exit (0);
		}
	if((fp2 =fopen(outfile,"w")) == NULL)
		{
			printf("Can't open outfile %s\n",outfile);
			fclose(fp1);	
			exit (0);
		
		}
	while((letter= fgetc(fp1)) != EOF)
		{
		if(letter==0xFF) /*first hex digit of jpeg */
		    {
			ishdr1= letter;
			ishdr2= fgetc(fp1);
			if(HDR1==ishdr1 && HDR2==ishdr2)flag=1;
			fseek(fp1,-1L,SEEK_CUR); /* back up one */
		    }

		if(letter==0x41)       /* A in Adobe */
		    {
			isadobe[0]=letter;
			isadobe[1]= fgetc(fp1);
			isadobe[2]= fgetc(fp1);
			isadobe[3]= fgetc(fp1);
			isadobe[4]= fgetc(fp1);
			isadobe[5]='\0';
			fseek(fp1,-4L,SEEK_CUR); /* back up four */
			if(strcmp(ADOBE,isadobe)==0)flag1++;

		    }

		if(flag == 1 && flag1 != 1)
		    {
			fseek(fp1,-1L,SEEK_CUR); /* Back up and read */
			letter=fgetc(fp1);       /* byte just analyzed */
			fputc(letter,fp2);       /* and write it to .jpg */
		    }
		}
		
	if(flag == 1 && flag1 > 1){
	printf("%s written, type 1 Adobe enbedded.\n",outfile);
	fclose(fp1);
	fclose(fp2);
	return 0;}

	else{ 
	rewind(fp1);
	rewind(fp2);
	   }

	while(cnt1<100 && ((letter= fgetc(fp1)) != EOF))
		{
		if(letter==0x57)       /* W in WWBBxxxx */
		    {
			isalgo1[0]=letter;
			isalgo1[1]= fgetc(fp1);
			isalgo1[2]= fgetc(fp1);
			isalgo1[3]= fgetc(fp1);
			isalgo1[4]= fgetc(fp1);
			isalgo1[5]= fgetc(fp1);
			isalgo1[6]= fgetc(fp1);
			isalgo1[7]= fgetc(fp1);
			isalgo1[8]='\0';
			if(strcmp(ALGO1,isalgo1)==0)
			{flag1++;verwb=1;}
	                if(strcmp(ALGO2,isalgo1)==0)
			{flag1++;verwb=2;}
			if(!verwb)fseek(fp1,-7L,SEEK_CUR);
        		}

/* matrix stuff goes here. write now decrypt next */
		if(verwb>1)
		    {
			if(verwb==1)magicvalue=0xA4;
			if(verwb==2)magicvalue=0xF2;
			while(cnt<100 && ((letter= fgetc(fp1)) != EOF)){
				A[cnt]=letter;cnt++;
			}

			while(cnt1<100 && ((letter= fgetc(fp1)) != EOF)){
				C[cnt1]=letter;B[cnt1]=letter;cnt1++;
			}

			/* decryption algorythm */
			counter=0;
			while(counter<100){
			A[counter] = ~A[counter];
			B[counter] = B[counter] ^ A[counter];
			B[counter] = B[counter] ^ magicvalue;
			counter++;
			}


		    }
		}



			counter=0;     /* altered 2nd 100 bytes */
			while(counter<100)
			    {
				letter=B[counter];
				fputc(letter,fp2);
				counter++;
			    }

			counter=0;    /* saved 2nd 100 bytes */
			while(counter<100)
			    {
				letter=C[counter];
				fputc(letter,fp2);
				counter++;
			    }

			while((letter = fgetc(fp1)) != EOF)
			    {
				fputc(letter,fp2);
			    }		
printf("%s written, type %s encrypted.\n",outfile,isalgo1);
	fclose(fp1);
	fclose(fp2);


	   
return 0;
}