#include <stdio.h>
#include <string.h>

//#define PRINTABLE_HASH_FF16

/*
Find a printable 4-character key, remembering (see Photoshop API guide):
- All IDs starting with an uppercase letter are reserved by Adobe.
- All IDs that are all uppercase are reserved by Apple.
- All IDs that are all lowercase are reserved by Apple.
- This leaves all IDs that begin with a lowercase letter and have at least
  one uppercase letter for you and other plug-in developers.
*/
unsigned long printablehash(unsigned long hash) {
#ifdef PRINTABLE_HASH_FF16
	// FilterFoundry version 1.6 hashing by Toby Thain
	// Only accepts upper case at the last character
	// 0       = 'a  A'
	// 6100899 = 'z~~Z'
	unsigned long key = 'a' + (hash % 26);  hash /= 26; // first lower case
	key = (key << 8) | (' ' + (hash % 95)); hash /= 95; // any printable
	key = (key << 8) | (' ' + (hash % 95)); hash /= 95; // any printable
	return  (key << 8) | ('A' + (hash % 26));           // last upper case
#else
	// FilterFoundry version 1.7 hashing by Daniel Marschall
	// Accepts upper case at character 2, 3 or 4
	// Spaces are only set the right as padding to make a code shorter
	// 0        = 'aA  '
	// 13530139 = 'zZZZ'
	// The key-space is ~2.22 times larger
	long lowlim;
	long uplim;
	int upperCaseInfo;
	int length;
	int lastThreeCharInfo;
	int firstChar;
	unsigned long key;
	int found;
	int i,j,k;

	uplim = 0;
	for (k=1; k<4; k++) {
		int mask;
		if (k == 1) mask = 0b1;
		if (k == 2) mask = 0b11;
		if (k == 3) mask = 0b111;
		for (i=1; i<=mask; i++) {
			// 'k' characters
			long test = 1;
			for (j=0; j<k; ++j) {
				test *= ((i&(1<<j)) != 0) ? 26 : 94-26;
			}
			uplim += test;
		}
	}

	lastThreeCharInfo = hash % uplim; hash /= uplim;
	firstChar = hash%26; hash /= 26;

	lowlim = 0;
	uplim = 0;
	found = 0;
	for (k=1; k<4; k++) {
		int mask;
		if (k == 1) mask = 0b1;
		if (k == 2) mask = 0b11;
		if (k == 3) mask = 0b111;
		if (!found) for (i=1; i<=mask; i++) {
			// 'k' characters
			long test = 1;
			for (j=0; j<k; ++j) {
				test *= ((i&(1<<j)) != 0) ? 26 : 94-26;
			}
			uplim += test;
			if ((lastThreeCharInfo >= lowlim) && (lastThreeCharInfo < uplim)) {
				lastThreeCharInfo -= lowlim;
				found = 1;
				length = k;
				upperCaseInfo = i;
				break;
			}
			lowlim = uplim;
		}
	}

	key = ('a' + firstChar) << 24; // first char is lower-case
	for (i=0; i<length; ++i) {
		char res;
		if ((upperCaseInfo&(1<<i)) == 0) {
			res = '!' + (lastThreeCharInfo % (94-26));
			if (res >= 'A') res += 26;
			lastThreeCharInfo /= (94-26);
		} else {
			res = 'A' + (lastThreeCharInfo % 26);
			lastThreeCharInfo /= 26;
		}
		key |= res << (8*(i+(4-length-1))); // 2nd, 3rd, 4th char are either upper-case or any printable char
	}
	if (length == 1) {
		key &= 0xFFFF0000;
		key |= ' ' << 8;
		key |= ' ';
	}
	if (length == 2) {
		key &= 0xFFFFFF00;
		key |= ' ';
	}
	return key;
#endif
}





int main()
{
    unsigned long x;

    for (long i=0; i<1; i++) {
	x = printablehash(i);
        printf("%i = '%c%c%c%c'\n", (int)i, (int)((x>>24) & 0xFF), (int)((x>>16) & 0xFF), (int)((x>>8) & 0xFF), (int)((x>>0) & 0xFF));
    }
//return 0;
    for (long i=0; 1; i++) {
	x = printablehash(i);

	if (((x>>24) & 0xFF) == 'z')
		if (((x>>16) & 0xFF) == 'Z')
			if (((x>>8) & 0xFF) == 'Z')
				if (((x>>0) & 0xFF) == 'Z') {
					printf("bingo 1.7! %i\n", i);
				        printf("%i = '%c%c%c%c'\n", (int)i, (int)((x>>24) & 0xFF), (int)((x>>16) & 0xFF), (int)((x>>8) & 0xFF), (int)((x>>0) & 0xFF));
					i++;
					x = printablehash(i);
				        printf("%i = '%c%c%c%c'\n", (int)i, (int)((x>>24) & 0xFF), (int)((x>>16) & 0xFF), (int)((x>>8) & 0xFF), (int)((x>>0) & 0xFF));
					break;
				}



    }
    return 0;
}