/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011  Cyan Worlds, Inc.

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 3 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, see <http://www.gnu.org/licenses/>.

Additional permissions under GNU GPL version 3 section 7

If you modify this Program, or any covered work, by linking or
combining it with any of RAD Game Tools Bink SDK, Autodesk 3ds Max SDK,
NVIDIA PhysX SDK, Microsoft DirectX SDK, OpenSSL library, Independent
JPEG Group JPEG library, Microsoft Windows Media SDK, or Apple QuickTime SDK
(or a modified version of those libraries),
containing parts covered by the terms of the Bink SDK EULA, 3ds Max EULA,
PhysX SDK EULA, DirectX SDK EULA, OpenSSL and SSLeay licenses, IJG
JPEG Library README, Windows Media SDK EULA, or QuickTime SDK EULA, the
licensors of this Program grant you additional
permission to convey the resulting work. Corresponding Source for a
non-source form of such a combination shall include the source code for
the parts of OpenSSL and IJG JPEG Library used as well as that of the covered
work.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/
////////////////////////////////////////////////////////////////////
// This little app checks to see if the specified envrionment
// variable exists, creating it if necessary. If the variable
// doesn't exist, the app prompts the user with the Browse for
// Folder dialog box then sets the envrionment variable, using the
// selected folder as the value.
//
// Example:
// C:\>CheckFolderVar maxr4dir "Select the folder where max is installed then click Ok."
//


////////////////////////////////////////////////////////////////////

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

////////////////////////////////////////////////////////////////////

std::string gCurrentValue;

// get window handle of cancel button so we can disable it.
BOOL CALLBACK EnumChildWindowsCallbackProc(HWND hwnd,LPARAM lParam)
{
    char text[256];
    GetWindowText(hwnd,text,256);
    if (stricmp(text,"Cancel")==0)
    {
        *((HWND*)lParam) = hwnd;
        return FALSE;
    }
    return TRUE;
}

int CALLBACK BrosweForFolderCallbackProc(HWND hwnd,UINT uMsg,LPARAM lp, LPARAM pData)
{
    switch(uMsg)
    {
    case BFFM_INITIALIZED:
        // disable cancel button
        HWND hCancelBtn = NULL;
        EnumChildWindows(hwnd,EnumChildWindowsCallbackProc,(LPARAM)&hCancelBtn);
        EnableWindow(hCancelBtn,FALSE);
        SendMessage(hwnd,BFFM_SETSELECTION,true,(LPARAM)gCurrentValue.data());
        break;
    }
    return 0;
}

////////////////////////////////////////////////////////////////////
int main(int argc, char ** argv)
{
    if (argc<2)
    {
        fprintf(stderr,"Usage: CheckFolderVar varname [-replace] [\"prompt msg\"]\n");
        return EXIT_FAILURE;
    }

    // read cmdline
    char ** args = argv;
    char * varname = NULL;
    bool replace = false;
    char prompt[1024] = "";
    for (int i=1; i<argc; i++)
    {
        if (!varname)
            varname = args[i];
        else if (stricmp(args[i],"-replace")==0)
            replace = true;
        else
            sprintf(prompt,"%s",args[i]);
    }
    if (prompt[0] == '\0')
        sprintf(prompt,"Set the '%s' environment variable by browsing to the desired folder and then click Ok:",varname);


    // open registry key
    HKEY hEnvKey;
    RegOpenKeyEx(HKEY_CURRENT_USER,"Environment",0,KEY_WRITE|KEY_READ,&hEnvKey);

    // check if var already exists
    char value[MAX_PATH];
    DWORD bufsz = MAX_PATH;
    if(RegQueryValueEx(hEnvKey,varname,NULL,NULL,(LPBYTE)value,&bufsz) == ERROR_SUCCESS)
    {
        // exit if already exists and not replace
        if (!replace)
        {
            RegCloseKey(hEnvKey);
            return EXIT_SUCCESS;
        }
        gCurrentValue = value;
    }

TryAgain:
    // open browse for folder dialog
    BROWSEINFO  bInfo;
    LPITEMIDLIST itemList;
    LPMALLOC  shMalloc;
    memset( &bInfo, 0, sizeof( bInfo ) );
    bInfo.hwndOwner = NULL;
    bInfo.pidlRoot = NULL;
    bInfo.lpszTitle = prompt;
    bInfo.ulFlags = BIF_NEWDIALOGSTYLE;
    bInfo.pszDisplayName = NULL;
    bInfo.lpfn = BrosweForFolderCallbackProc;
    itemList = SHBrowseForFolder(&bInfo);
    if (!itemList)
        goto TryAgain;
    SHGetPathFromIDList(itemList,value);
    SHGetMalloc(&shMalloc);
    shMalloc->Free(itemList);
    shMalloc->Release();

    // set environment var
    RegSetValueEx(hEnvKey,varname,0,REG_SZ,(const BYTE*)value,strlen(value));

    // close registry key
    RegCloseKey(hEnvKey);

    // bubbye
    return EXIT_SUCCESS;
}
