/*
 * PROJECT:         input.dll
 * FILE:            dll/cpl/input/layout_list.c
 * PURPOSE:         input.dll
 * PROGRAMMER:      Dmitry Chapyshev (dmitry@reactos.org)
 */

#include "layout_list.h"


static LAYOUT_LIST_NODE *_LayoutList = NULL;


static LAYOUT_LIST_NODE*
LayoutList_AppendNode(DWORD dwId, DWORD dwSpecialId, const WCHAR *pszName)
{
    LAYOUT_LIST_NODE *pCurrent;
    LAYOUT_LIST_NODE *pNew;

    if (pszName == NULL)
        return NULL;

    pCurrent = _LayoutList;

    pNew = (LAYOUT_LIST_NODE*)malloc(sizeof(LAYOUT_LIST_NODE));
    if (pNew == NULL)
        return NULL;

    ZeroMemory(pNew, sizeof(LAYOUT_LIST_NODE));

    pNew->pszName = _wcsdup(pszName);
    if (pNew->pszName == NULL)
    {
        free(pNew);
        return NULL;
    }

    pNew->dwId = dwId;
    pNew->dwSpecialId = dwSpecialId;

    if (pCurrent == NULL)
    {
        _LayoutList = pNew;
    }
    else
    {
        while (pCurrent->pNext != NULL)
        {
            pCurrent = pCurrent->pNext;
        }

        pNew->pPrev = pCurrent;
        pCurrent->pNext = pNew;
    }

    return pNew;
}


VOID
LayoutList_Destroy(VOID)
{
    LAYOUT_LIST_NODE *pCurrent;

    if (_LayoutList == NULL)
        return;

    pCurrent = _LayoutList;

    while (pCurrent != NULL)
    {
        LAYOUT_LIST_NODE *pNext = pCurrent->pNext;

        free(pCurrent->pszName);
        free(pCurrent);

        pCurrent = pNext;
    }

    _LayoutList = NULL;
}

static BOOL
LayoutList_ReadLayout(HKEY hLayoutKey, LPCWSTR szLayoutId, LPCWSTR szSystemDirectory)
{
    WCHAR szBuffer[MAX_PATH], szFilePath[MAX_PATH], szDllPath[MAX_PATH];
    INT iIndex, iLength = 0;
    DWORD dwSize, dwSpecialId, dwLayoutId = DWORDfromString(szLayoutId);
    HINSTANCE hDllInst;

    dwSize = sizeof(szBuffer);
    if (RegQueryValueExW(hLayoutKey, L"Layout File", NULL, NULL,
                         (LPBYTE)szBuffer, &dwSize) != ERROR_SUCCESS)
    {
        return FALSE; /* No "Layout File" value */
    }

    /* Build the "Layout File" full path and check existence */
    StringCchPrintfW(szFilePath, ARRAYSIZE(szFilePath), L"%s\\%s", szSystemDirectory, szBuffer);
    if (GetFileAttributesW(szFilePath) == INVALID_FILE_ATTRIBUTES)
        return FALSE; /* No layout file found */

    /* Get the special ID */
    dwSpecialId = 0;
    dwSize = sizeof(szBuffer);
    if (RegQueryValueExW(hLayoutKey, L"Layout Id", NULL, NULL,
                         (LPBYTE)szBuffer, &dwSize) == ERROR_SUCCESS)
    {
        dwSpecialId = DWORDfromString(szBuffer);
    }

    /* If there is a valid "Layout Display Name", then use it as the entry name */
    dwSize = sizeof(szBuffer);
    if (RegQueryValueExW(hLayoutKey, L"Layout Display Name", NULL, NULL,
                         (LPBYTE)szBuffer, &dwSize) == ERROR_SUCCESS && szBuffer[0] == L'@')
    {
        /* FIXME: Use shlwapi!SHLoadRegUIStringW instead if it had fully implemented */

        /* Move to the position after the character "@" */
        WCHAR *pBuffer = szBuffer + 1;

        /* Get a pointer to the beginning ",-" */
        WCHAR *pIndex = wcsstr(pBuffer, L",-");

        if (pIndex)
        {
            /* Convert the number in the string after the ",-" */
            iIndex = _wtoi(pIndex + 2);

            *pIndex = 0; /* Cut the string */

            if (ExpandEnvironmentStringsW(pBuffer, szDllPath, ARRAYSIZE(szDllPath)) != 0)
            {
                hDllInst = LoadLibraryW(szDllPath);
                if (hDllInst)
                {
                    iLength = LoadStringW(hDllInst, iIndex, szBuffer, ARRAYSIZE(szBuffer));
                    FreeLibrary(hDllInst);

                    if (iLength > 0)
                    {
                        LayoutList_AppendNode(dwLayoutId, dwSpecialId, szBuffer);
                        return TRUE;
                    }
                }
            }
        }
    }

    /* Otherwise, use "Layout Text" value as the entry name */
    dwSize = sizeof(szBuffer);
    if (RegQueryValueExW(hLayoutKey, L"Layout Text", NULL, NULL,
                         (LPBYTE)szBuffer, &dwSize) == ERROR_SUCCESS)
    {
        LayoutList_AppendNode(dwLayoutId, dwSpecialId, szBuffer);
        return TRUE;
    }

    return FALSE;
}

VOID
LayoutList_Create(VOID)
{
    WCHAR szSystemDirectory[MAX_PATH], szLayoutId[MAX_PATH];
    DWORD dwSize, dwIndex;
    HKEY hKey, hLayoutKey;

    if (!GetSystemDirectoryW(szSystemDirectory, ARRAYSIZE(szSystemDirectory)))
        return;

    if (RegOpenKeyExW(HKEY_LOCAL_MACHINE, L"SYSTEM\\CurrentControlSet\\Control\\Keyboard Layouts",
                      0, KEY_ENUMERATE_SUB_KEYS, &hKey) != ERROR_SUCCESS)
    {
        return;
    }

    for (dwIndex = 0; ; ++dwIndex)
    {
        dwSize = ARRAYSIZE(szLayoutId);
        if (RegEnumKeyExW(hKey, dwIndex, szLayoutId, &dwSize, NULL, NULL,
                          NULL, NULL) != ERROR_SUCCESS)
        {
            break;
        }

        if (RegOpenKeyExW(hKey, szLayoutId, 0, KEY_QUERY_VALUE, &hLayoutKey) == ERROR_SUCCESS)
        {
            LayoutList_ReadLayout(hLayoutKey, szLayoutId, szSystemDirectory);
            RegCloseKey(hLayoutKey);
        }
    }

    RegCloseKey(hKey);
}


LAYOUT_LIST_NODE*
LayoutList_GetByHkl(HKL hkl)
{
    LAYOUT_LIST_NODE *pCurrent;

    if ((HIWORD(hkl) & 0xF000) == 0xF000)
    {
        DWORD dwSpecialId = (HIWORD(hkl) & 0x0FFF);

        for (pCurrent = _LayoutList; pCurrent != NULL; pCurrent = pCurrent->pNext)
        {
            if (dwSpecialId == pCurrent->dwSpecialId)
            {
                return pCurrent;
            }
        }
    }
    else
    {
        for (pCurrent = _LayoutList; pCurrent != NULL; pCurrent = pCurrent->pNext)
        {
            if (HIWORD(hkl) == LOWORD(pCurrent->dwId))
            {
                return pCurrent;
            }
        }
    }

    return NULL;
}


LAYOUT_LIST_NODE*
LayoutList_GetFirst(VOID)
{
    return _LayoutList;
}