/* GCNcrypt - Gamecube AR Crypto Program
 *
 * Copyright notice for this file:
 *  Copyright (C) 2003-2004 Parasyte
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */


#include "gcncrypt.h"

int total;


char ucase(char buffer) {
	if ((buffer >= 'a') && (buffer <= 'z'))
		buffer -= 0x20;
	return buffer;
}

int alphatobin(u32 *dst, char alpha[][14], int size) {
	int i,j=0,k;
	int ret=0,org=(size+1);
	u32 bin[2];
	u8 parity;

	while (size) {
		bin[0]=0;
		for (i = 0; i < 6; i++) {
			bin[0] |= (GETVAL(filter,alpha[j>>1][i]) << (((5-i)*5)+2));
		}
		bin[0] |= (GETVAL(filter,alpha[j>>1][6]) >> 3);
		dst[j++] = bin[0];

		bin[1]=0;
		for (i = 0; i < 6; i++) {
			bin[1] |= (GETVAL(filter,alpha[j>>1][i+6]) << (((5-i)*5)+4));
		}
		bin[1] |= (GETVAL(filter,alpha[j>>1][12]) >> 1);
		dst[j++] = bin[1];

		//verify parity bit
		k=0;
		parity=0;
		for (i = 0; i < 64; i++) {
			if (i == 32) k++;
			parity ^= (bin[k] >> (i-(k<<5)));
		}
		if ((parity&1) != (GETVAL(filter,alpha[(j-2)>>1][12])&1)) ret=(org-size);

		size--;
	}

	return ret;
}

void DecryptUpdateText(char *textout, char alpha[][14], u32 *codes, int num) {
	char str[128];
	int i,ret;

	total++;
	if ((ret=alphatobin(codes,alpha,num))) {
		sprintf(str,"Code Decryption Error\nParity Check Failed\n\nCode #%d, Line %d",total,ret);
		MessageBox(hWindow, str, "ERROR", MB_ICONERROR | MB_OK);
		batchdecrypt(codes,num<<1);
	}
	else if (!batchdecrypt(codes,num<<1)) {
		sprintf(str,"Code Decryption Error\nCRC Check Failed\n\nCode #%d",total);
		MessageBox(hWindow, str, "ERROR", MB_ICONERROR | MB_OK);
	}
	for (i = 0; i < (num<<1); i+=2) {
		sprintf(str,"%08X %08X\r\n",codes[i],codes[i+1]);
		strcat(textout,str);
	}
}

void DecryptParseList() {
	u32 codes[1200];
	char textin[TEXTSIZE],textout[TEXTSIZE];
	char alpha[600][14],tmp[14];
	int i,j=0,num=0,chr=0,crlf=0;
	int strbegin=0,strend=0;

	total=0;

	memset(alpha,0,600*14);
	memset(textout,0,TEXTSIZE);
	SetDlgItemText(hWindow,102,"");
	GetDlgItemText(hWindow,101,textin,TEXTSIZE);

	//this thing runs through the input text, trying to find potential codes
	//when found, it virtually replaces them with decrypted codes
	for (i = 0; i < strlen(textin); i++) {
		if ((chr == 4) || (chr == 8)) {
			if (textin[i] != '-') chr=0;
			else if (++i >= TEXTSIZE) break;
		}

		if (ISALPHA(filter,ucase(textin[i]))) tmp[chr++] = ucase(textin[i]);
		else if (textin[i] == '\n') crlf++;
		else chr=0;

		if (chr == 13) {
			if ((strend < strbegin) || (!num)) strend = (i-14);
			chr=0;
			crlf=0;
			strcpy(alpha[num++],tmp);
		}
		if ((num) && (crlf > 1)) {
			memcpy(textout+strlen(textout),textin+strbegin,strend-strbegin);
			strbegin=(i-1);
			j = strlen(textout);
			while ((textout[j] != '\n') && (j >= 0)) textout[j--] = '\0';

			DecryptUpdateText(textout,alpha,codes,num);
			num=0;
		}
	}

	if (((strend == 0) && (!num)) || (strbegin > strend)) strend=i;
	memcpy(textout+strlen(textout),textin+strbegin,strend-strbegin);

	if (num) {
		j = strlen(textout);
		while ((textout[j] != '\n') && (j >= 0)) textout[j--] = '\0';
		DecryptUpdateText(textout,alpha,codes,num);
	}
	SetDlgItemText(hWindow,102,textout);
	if (dogameid) {
		sprintf(tmp,"%03X",gameid);
		SetDlgItemText(hWindow,103,tmp);
		SendMessage(GetDlgItem(hWindow,501),CB_SETCURSEL,(WPARAM)region,(LPARAM)0);
	}
}


void bintoalpha(char *dst, u32 *src, int index) {
	int i,j=0,k;
	u8 parity=0;

	//convert hex directly to alpha-numeric equivelant
	for (i = 0; i < 6; i++) {
		if (i == 4) {
			dst[i] = '-';
			j++;
		}
		dst[i+j] = filter[(src[index] >> (((5-i)*5)+2)) & 0x1F];
	}
	dst[i+j] = filter[((src[index]<<3)|(src[index+1]>>29))&0x1F];
	j+=6;
	for (i = 1; i < 6; i++) {
		if (i == 2) {
			dst[i+j] = '-';
			j++;
		}
		dst[i+j] = filter[(src[index+1] >> (((5-i)*5)+4)) & 0x1F];
	}
	j+=i;

	//set parity bit
	k=0;
	for (i = 0; i < 64; i++) {
		if (i == 32) k++;
		parity ^= (src[index+k] >> (i-(k<<5)));
	}

	dst[j] = filter[((src[index+1]<<1)&0x1E)|(parity&1)];
	dst[j+1] = '\0';
}

void EncryptUpdateText(char *textout, u32 *codes, int num) {
	char str[128];
	int i;

	total++;
	if (!batchencrypt(codes,num)) {
		sprintf(str,"Code Encryption Error\nCode #%d",total);
		MessageBox(hWindow, str, "ERROR", MB_ICONERROR | MB_OK);
	}
	for (i = 0; i < num; i+=2) {
		bintoalpha(str,codes,i);
		strcat(textout,str);
		strcat(textout,"\r\n");
	}
}

void EncryptParseList() {
	u8 mcode;
	u32 codes[1200];
	char textin[TEXTSIZE],textout[TEXTSIZE];
	char alpha[600][14],tmp[18];
	int i,j=0,num=0,chr=0,crlf=0;
	int strbegin=0,strend=0;

	total=0;

	//init random number generator
	srand(GetTickCount());

	//get Game ID
	if (dogameid) {
		GetDlgItemText(hWindow,103,tmp,4);
		sscanf(tmp,"%hx",&gameid);
		gameid&=0x07FF;
	}

	memset(alpha,0,600*14);
	memset(textout,0,TEXTSIZE);
	memset(tmp,0,18);
	SetDlgItemText(hWindow,102,"");
	GetDlgItemText(hWindow,101,textin,TEXTSIZE);

	//this thing runs through the input text, trying to find potential codes
	//when found, it virtually replaces them with encrypted codes
	for (i = 0; i < strlen(textin); i++) {
		if (chr == 8) {
			if (textin[i] != ' ') chr=0;
			else tmp[chr++] = ' ';
		}
		else if (ISHEX(hex,ucase(textin[i]))) tmp[chr++] = ucase(textin[i]);
		else if (textin[i] == '\n') crlf++;
		else chr=0;

		if (chr == 17) {
			if ((strend < strbegin) || (!num)) strend = (i-16);
			chr=0;
			crlf=0;
			sscanf(tmp,"%x %x",&codes[num],&codes[num+1]);
			num+=2;
		}
		if ((num) && (crlf > 1)) {
			memcpy(textout+strlen(textout),textin+strbegin,strend-strbegin);
			strbegin=(i-1);
			j = strlen(textout);
			while ((textout[j] != '\n') && (j >= 0)) textout[j--] = '\0';

			if (dogameid) {
				mcode=0;
				for (j = 0; j < num; j+=2) if ((codes[j] >> 25) == 0x62) mcode=1;
				region = SendMessage(GetDlgItem(hWindow,501),CB_GETCURSEL,(WPARAM)0,(LPARAM)0);
				j=num;
				num+=2;
				while (j >= 0) codes[j+2] = codes[j--];
				codes[0] = ((gameid << 17)|(rand()%0x20000));
				codes[1] = (0x08000000|(mcode<<31)|(region<<28));
			}
			EncryptUpdateText(textout,codes,num);
			num=0;
		}
	}

	if (((strend == 0) && (!num)) || (strbegin > strend)) strend=i;
	memcpy(textout+strlen(textout),textin+strbegin,strend-strbegin);

	if (num) {
		j = strlen(textout);
		while ((textout[j] != '\n') && (j >= 0)) textout[j--] = '\0';
		if (dogameid) {
			mcode=0;
			for (j = 0; j < num; j+=2) if ((codes[j] >> 25) == 0x62) mcode=1;
			region = SendMessage(GetDlgItem(hWindow,501),CB_GETCURSEL,(WPARAM)0,(LPARAM)0);
			j=num;
			num+=2;
			while (j >= 0) codes[j+2] = codes[j--];
			codes[0] = ((gameid << 17)|(rand()%0x20000));
			codes[1] = (0x08000000|(mcode<<31)|(region<<28));
		}
		EncryptUpdateText(textout,codes,num);
	}
	SetDlgItemText(hWindow,102,textout);
}

void gcncryptKill() {
	DeleteObject(hNewFont);
	DestroyWindow(hWindow);
	hWindow=NULL;
}

BOOL CALLBACK MainCallB(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam) {
	LOGFONT lf;

	switch(uMsg) {
		case WM_INITDIALOG:
			//the almighty buildseeds() function!! without this, the crypto routines are useless
			buildseeds();

			//setup font
			hFont = (HFONT)SendMessage(hwndDlg, WM_GETFONT, 0, 0);
			GetObject(hFont, sizeof(LOGFONT), &lf);
			strcpy(lf.lfFaceName,"Courier");
			hNewFont = CreateFontIndirect(&lf);

			SendDlgItemMessage(hwndDlg,101,WM_SETFONT,(WPARAM)hNewFont,FALSE);
			SendDlgItemMessage(hwndDlg,102,WM_SETFONT,(WPARAM)hNewFont,FALSE);
			SendDlgItemMessage(hwndDlg,103,WM_SETFONT,(WPARAM)hNewFont,FALSE);

			//set text limits
			SendDlgItemMessage(hwndDlg,101,EM_SETLIMITTEXT,(TEXTSIZE-1),0);
			SendDlgItemMessage(hwndDlg,103,EM_SETLIMITTEXT,3,0);

			//tick checkbox
			CheckDlgButton(hwndDlg,401,BST_CHECKED);

			//fill region list box
			SendMessage(GetDlgItem(hwndDlg,501),CB_ADDSTRING,(WPARAM)0,(LPARAM)("USA"));
			SendMessage(GetDlgItem(hwndDlg,501),CB_ADDSTRING,(WPARAM)0,(LPARAM)("PAL"));
			SendMessage(GetDlgItem(hwndDlg,501),CB_ADDSTRING,(WPARAM)0,(LPARAM)("Japan"));
			SendMessage(GetDlgItem(hwndDlg,501),CB_ADDSTRING,(WPARAM)0,(LPARAM)("Null"));
			SendMessage(GetDlgItem(hwndDlg,501),CB_SETCURSEL,(WPARAM)0,(LPARAM)0);
			break;
		case WM_CLOSE:
		case WM_QUIT:
			gcncryptKill();
			break;
		case WM_COMMAND:
			switch(HIWORD(wParam)) {
				case BN_CLICKED:
					switch(LOWORD(wParam)) {
						case 201: //Decrypt
							DecryptParseList();
							break;
						case 202: //Encrypt
							EncryptParseList();
							break;
						case 301: //Close
							gcncryptKill();
							break;
						case 302: //Clear (input)
							SetDlgItemText(hwndDlg,101,"");
							break;
						case 303: //Clear (output)
							SetDlgItemText(hwndDlg,102,"");
							break;
						case 401: //Game ID:
							dogameid^=1;
							SendDlgItemMessage(hwndDlg,103,EM_SETREADONLY,dogameid^1,0);
							EnableWindow(GetDlgItem(hwndDlg,501),dogameid);
							break;
					}
					break;
			}
			break;
	}
	return FALSE;
}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hprevinstance, LPSTR lpcmdline, int ncmdshow) {
	MSG msg;
	RECT wndRect,dskRect;
	int w,h;

	ghInstance = hInstance;
	hWindow = CreateDialog(ghInstance,"MAIN",NULL,MainCallB);
	if (!hWindow) {
		MessageBox(NULL, "Could not create main dialog", "ERROR", MB_ICONERROR | MB_OK);
		return 0;
	}

	//load and set dialog icons
	iWindow = LoadIcon(ghInstance,"ICON");
	SendMessage(hWindow,WM_SETICON,ICON_BIG,(LPARAM)iWindow);
	SendMessage(hWindow,WM_SETICON,ICON_SMALL,(LPARAM)iWindow);

	//change title bar to include version number
	SetWindowText(hWindow, TITLEBAR);

	//center dialog on screen
	GetWindowRect(hWindow,&wndRect);
	GetWindowRect(GetDesktopWindow(),&dskRect);
	w = (wndRect.right-wndRect.left);
	h = (wndRect.bottom-wndRect.top);
	MoveWindow(hWindow,((dskRect.right/2)-(w/2)),((dskRect.bottom/2)-(h/2)),w,h,TRUE);

	//display dialog
	ShowWindow(hWindow,ncmdshow);
	UpdateWindow(hWindow);

	while (hWindow) {
		if (GetMessage(&msg,NULL,0,0)) {
			TranslateMessage(&msg);
			DispatchMessage(&msg);
		}
	}

	return msg.wParam;
}