/*
 * -----
 * Screenshot Sender - registry.js
 * -----
 * Provides Screenshot Sender registry access
 * -----
 */
 
 // todo
 // add functions to create 'hidden' registry functions
 
// Registry value types
var REG_NONE = 0;
var REG_SZ = 1;
var REG_EXPAND_SZ = 2;
var REG_BINARY = 3;
var REG_DWORD = 4;
var REG_MULTI_SZ = 7;
 
// Registry key locations  
var HKEY_CLASSES_ROOT = 0x80000000;
var HKEY_CURRENT_USER = 0x80000001;
var HKCU = HKEY_CURRENT_USER;
var HKEY_LOCAL_MACHINE = 0x80000002;
var HKEY_USERS = 0x80000003;
var HKEY_PERFORMANCE_DATA = 0x80000004;
var HKEY_PERFORMANCE_TEXT = 0x80000050;
var HKEY_PERFORMANCE_NLSTEXT = 0x80000060;
var HKEY_CURRENT_CONFIG = 0x80000005;
var HKEY_DYN_DATA = 0x80000006;
 
// Registry key constants
var KEY_READ = 0x20019;
var KEY_WRITE = 0x20006;
var KEY_EXECUTE = 0x20019;
var KEY_ALL_ACCESS = 0xf003f;
var REG_OPTION_NON_VOLATILE = 0;
var ERROR_SUCCESS = 0;
var ERROR_NO_MORE_ITEMS = 259;
 
/*
    Name:   Registry_CreateKey
    Purpose:    Creates a key in the registry
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Location to create. Last key in the path should be the only one that doesn't exist. Function
                is not recursive.
    Return: True if key was created properly/False if it failed
*/
function Registry_CreateKey(lKeyLocation, sKey) {
    var hKey = Interop.Allocate(4);
    if (Registry_KeyExist(lKeyLocation, sKey) == false) var lRetVal = Interop.Call('advapi32.dll', 'RegCreateKeyW', lKeyLocation, sKey, hKey);
    Registry_CloseKey(hKey.ReadDWORD(0));
    return lRetVal === ERROR_SUCCESS;
}
 
/*
    Name:   Registry_DeleteKey
    Purpose:    Deletes a key in the registry
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Key to delete. Must not have any subkeys or values
    Return: True if key was deleted properly/False if it failed
*/ 
function Registry_DeleteKey(lKeyLocation, sKey) {
    var hKey = Interop.Allocate(4);
    return Interop.Call('advapi32.dll', 'RegDeleteKeyW', lKeyLocation, sKey) === ERROR_SUCCESS;
}
 
/*
    Name:   Registry_DeleteKeyValue
    Purpose:    Deletes a value in the registry
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Location where the key to be deleted resides
            sKeyName - Key to be deleted
    Return: True if key was deleted properly/False if it failed
*/
function Registry_DeleteKeyValue(lKeyLocation, sKey, sKeyName) {
    var hKey = Interop.Allocate(4);
    var lRetVal = Interop.Call('advapi32.dll', 'RegOpenKeyExW', lKeyLocation, sKey, 0, KEY_WRITE, hKey)
    if (lRetVal === ERROR_SUCCESS) {
        lRetVal = Interop.Call('advapi32.dll', 'RegDeleteValueW', hKey.ReadDWORD(0), sKeyName);
        Registry_CloseKey(hKey.ReadDWORD(0));
        return lRetVal === ERROR_SUCCESS;
    }else{ return false; }
   
}
 
/*
    Name:   Registry_KeyExist
    Purpose:    Checks to see if a key exists in the registry
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Location to check
    Return: True if the key exists/False if it doesn't
*/ 
function Registry_KeyExist(lKeyLocation, sKey) {
    var hKey = Interop.Allocate(4);
    var lRetVal = Interop.Call('advapi32.dll', 'RegOpenKeyExW', lKeyLocation, sKey, 0, KEY_READ, hKey);
    Registry_CloseKey(hKey.ReadDWORD(0));
    return lRetVal === ERROR_SUCCESS;
}
 
/*
    Name:   Registry_KeyValueExist
    Purpose:    Checks to see if a value exists in the registry
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Location where the key should reside
            sKeyName - Key that is being checked to see if it exists
    Return: True if the value exists/False if it doesn't
*/ 
function Registry_KeyValueExist(lKeyLocation, sKey, sKeyName) {
    var hKey = Interop.Allocate(4);
   
    var lRetVal = Interop.Call('advapi32.dll', 'RegOpenKeyExW', lKeyLocation, sKey, 0, KEY_READ, hKey);
    if (lRetVal === ERROR_SUCCESS) {
        lRetVal = Interop.Call('advapi32.dll', 'RegQueryValueExW', hKey.ReadDWORD(0), sKeyName, 0, 0, 0, 0);
        Registry_CloseKey(hKey.ReadDWORD(0));
        return lRetVal === ERROR_SUCCESS;
    }else{ return false; }
}
 
/*
    Name:   Registry_EnumSubkeys
    Purpose:    Retrieves a all of the subkeys of a specific key from the registry
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Location where to retrieve the subkeys from
            sOut - Object to return the subkeys to
    Return: Array of subkeys / False if it failed
*/
function Registry_EnumSubkeys(lKeyLocation, sKey, sOut) {
    var hKey = Interop.Allocate(4);
    var lpName = Interop.Allocate((255 + 1) * 2);
    var lpcName = Interop.Allocate(4);
        lpcName.WriteDWORD(0, 255);
    var lpftLastWriteTime = Interop.Allocate(8);
    var lIndex = 0;
   
    var lRetVal = Interop.Call('advapi32.dll', 'RegOpenKeyExW', lKeyLocation, sKey, 0, KEY_READ, hKey);
    if (lRetVal === ERROR_SUCCESS) {
        while (Interop.Call('advapi32', 'RegEnumKeyExW', hKey.ReadDWORD(0), lIndex, lpName, lpcName, 0, 0, 0, 0) != ERROR_NO_MORE_ITEMS) {
            sOut[lpName.ReadString(0)] = '';
            ++lIndex;
            lpcName.WriteDWORD(0, 255);
            lpName.Size = 0;
            lpName = Interop.Allocate((255 + 1) * 2);
        }
        Registry_CloseKey(hKey.ReadDWORD(0));
        return sOut;
    } else { return false; }
}
 
/*
    Name:   Registry_EnumKeys
    Purpose:    Retrieves a all of the subkeys of a specific key from the registry
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Location where to retrieve the keys from
            sOut - Object which to store keys and values
    Return: Object containing keys and their values / False if it failed
*/
function Registry_EnumKeys(lKeyLocation, sKey, sOut) {
    var hKey = Interop.Allocate(4);
    var lpName = Interop.Allocate((255 + 1) * 2);
    var lpcName = Interop.Allocate(4);
        lpcName.WriteDWORD(0, 255);
    var lpType = Interop.Allocate(4);
    var lIndex = 0;
    var lRetVal = Interop.Call('advapi32.dll', 'RegOpenKeyExW', lKeyLocation, sKey, 0, KEY_READ, hKey);
    if (lRetVal === ERROR_SUCCESS) {
        while (Interop.Call('advapi32', 'RegEnumValueW', hKey.ReadDWORD(0), lIndex, lpName, lpcName, 0, lpType, 0, 0) !== ERROR_NO_MORE_ITEMS) {
            sOut[lpName.ReadString(0)] = Registry_GetKeyValue(HKCU, sKey, lpName.ReadString(0));
            ++lIndex;
            lpcName.WriteDWORD(0, 255);
            lpName = Interop.Allocate((255 + 1) * 2);
        }
        Registry_CloseKey(hKey.ReadDWORD(0));
        return sOut;
    } else { return false; }
}
 
/*
    Name:   Registry_GetKeyValue
    Purpose:    Get the type of key to generically call the function (useful if you don't remember the type)
    Parameters: lKeyLocation - Hive to look in for the sKey(ex. HKEY_CURRENT_USER)
            sKey - Location where the key should reside
            sKeyName - Key to retrieve the value of
    Return: Value of the registry key/False if it failed
*/
function Registry_GetKeyValue(lKeyLocation, sKey, sKeyName) {
    var hKey = Interop.Allocate(4);
    var buff_size = 255;
    var lBufferSize = Interop.Allocate(4);
    lBufferSize.WriteDWORD(0, 2 * buff_size);
    var lRetVal = Interop.Call('advapi32.dll', 'RegOpenKeyExW', lKeyLocation, sKey, 0, KEY_READ, hKey);
    if (lRetVal === ERROR_SUCCESS) {
        var lpType = Interop.Allocate(4);
        lRetVal = Interop.Call('advapi32.dll', 'RegQueryValueExW', hKey.ReadDWORD(0), sKeyName, 0, lpType, 0, lBufferSize);
        if (lRetVal === ERROR_SUCCESS) {
            switch (lpType.ReadDWORD(0)) {
                case REG_EXPAND_SZ :
                case REG_MULTI_SZ :
                case REG_SZ :
                    var Buffer = Interop.Allocate(2 * lBufferSize.ReadDWORD(0) + 2);
                    Interop.Call('advapi32.dll', 'RegQueryValueExW', hKey.ReadDWORD(0), sKeyName, 0, lpType, Buffer, lBufferSize);
                    Buffer = Buffer.ReadString(0);
                    break;
                case REG_DWORD:
                    var Buffer = Interop.Allocate(Math.max(4, lBufferSize.ReadDWORD(0)));
                    Interop.Call('Advapi32', 'RegQueryValueExW', hKey.ReadDWORD(0), sKeyName, 0, lpType, Buffer, lBufferSize);
                    Buffer = Buffer.ReadDWORD(0);
                    break;
                case REG_BINARY :
                    var Buffer = Interop.Allocate(2 * lBufferSize.ReadDWORD(0) + 2);
                    Interop.Call('advapi32.dll', 'RegQueryValueExW', hKey.ReadDWORD(0), sKeyName, 0, lpType, Buffer, lBufferSize);
                    Buffer = Buffer.ReadString(0);
                    break;
                default: return false; //Cannot read registry key
            }
            Registry_CloseKey(hKey.ReadDWORD(0));
            return Buffer;
        } else { return false; }
    } else { return false; }
}
 
/*
    Name:   Registry_SetKeyValue
    Purpose:    Set the value of key(useful if you don't remember the type)
    Parameters: lKeyLocation - Hive to save sKey in(ex. HKEY_CURRENT_USER)
            sKey - Location where the key will reside
            sKeyName - Key to create
            sKeyValue - Value of the key to be set
            lpType - Key type(ex. REG_DWORD)
    Return: True if succeeded /False if it failed
*/
function Registry_SetKeyValue(lKeyLocation, sKey, sKeyName, sKeyValue, lpType) {
    var hKey = Interop.Allocate(4);
    var lRetVal = Interop.Call('advapi32.dll', 'RegOpenKeyExW', lKeyLocation, sKey, 0, KEY_WRITE, hKey);
    if (lRetVal === ERROR_SUCCESS) {
        switch (lpType) {
            case REG_EXPAND_SZ :
            case REG_MULTI_SZ :
            case REG_SZ :
                sKeyValue = String(sKeyValue);
                var buff_size = sKeyValue.length;
                var lBufferSize = Interop.Allocate(4);
                lBufferSize.WriteDWORD(0, (2 * buff_size + 2));
                lRetVal = Interop.Call('advapi32.dll', 'RegSetValueExW', hKey.ReadDWORD(0), sKeyName, 0, lpType, sKeyValue, lBufferSize.ReadDWORD(0));
                break;
            case REG_DWORD :
                var lKeyValue = Interop.Allocate(4);
                lKeyValue.WriteDWORD(0, (sKeyValue & 0xFFFFFFFF));
                lRetVal = Interop.Call('advapi32.dll', 'RegSetValueExW', hKey.ReadDWORD(0), sKeyName, 0, REG_DWORD, lKeyValue, 4);
                break;
            case REG_BINARY :
                sKeyValue = String(sKeyValue);
                var lBufferSize = Interop.Allocate(4);
                lBufferSize.WriteDWORD(0, (2 * sKeyValue.length + 2));
                lRetVal = Interop.Call('advapi32.dll', 'RegSetValueExW', hKey.ReadDWORD(0), sKeyName, 0, REG_BINARY, sKeyValue, lBufferSize.ReadDWORD(0));
                break;
            default : return false;
        }
        Registry_CloseKey(hKey.ReadDWORD(0));
        return lRetVal === ERROR_SUCCESS;
    } else { return false; }
}
 
/*
    Name:   Registry_CloseKey
    Purpose:    Closes the open handle to the registry
    Parameters: hKey - handle to the open registry key
    Return: True if it closed / False if it failed
*/
function Registry_CloseKey(hKey) {
    return Interop.Call('advapi32.dll', 'RegCloseKey', hKey) === ERROR_SUCCESS;
}