/**
 * PROJECT:         ExectOS
 * COPYRIGHT:       See COPYING.md in the top level directory
 * FILE:            xtldr/config.c
 * DESCRIPTION:     XT Boot Loader Configuration
 * DEVELOPERS:      Rafal Kupiec <belliash@codingworkshop.eu.org>
 */

#include <xtldr.h>


/**
 * Loads configuration file from the specified directory on the FS0:/ drive.
 *
 * @param ConfigDirectory
 *        Specifies a path to the directory containing the configuration file.
 *
 * @param ConfigFile
 *        Specifies the name of the configuration file.
 *
 * @param ConfigData
 *        Provides a buffer to store the data read from the configuration file.
 *
 * @return This routine returns status code.
 *
 * @since XT 1.0
 */
XTCDECL
EFI_STATUS
BlpLoadConfigurationFile(IN CONST PWCHAR ConfigDirectory,
                         IN CONST PWCHAR ConfigFile,
                         OUT PCHAR *ConfigData)
{
    PEFI_FILE_HANDLE DirHandle, FsHandle;
    EFI_HANDLE DiskHandle;
    EFI_STATUS Status;
    SIZE_T FileSize;

    /* Open EFI volume */
    Status = BlOpenVolume(NULL, &DiskHandle, &FsHandle);
    if(Status != STATUS_EFI_SUCCESS)
    {
        /* Failed to open a volume */
        return Status;
    }

    /* Open specified directory, containing the configuration file and close the FS immediately */
    Status = FsHandle->Open(FsHandle, &DirHandle, ConfigDirectory, EFI_FILE_MODE_READ, 0);
    FsHandle->Close(FsHandle);

    /* Check if directory opened successfully */
    if(Status != STATUS_EFI_SUCCESS)
    {
        /* Failed to open directory */
        BlCloseVolume(DiskHandle);
        return Status;
    }

    /* Read configuration file */
    Status = BlReadFile(DirHandle, ConfigFile, (PVOID *)ConfigData, &FileSize);

    /* Close EFI volume */
    BlCloseVolume(DiskHandle);

    /* Return read status */
    return STATUS_EFI_SUCCESS;
}

/**
 * Parses command line arguments and updates global configuration.
 *
 * @return This routine does not return any value.
 *
 * @since XT 1.0
 */
XTCDECL
VOID
BlpParseCommandLineOptions(VOID)
{
    EFI_GUID LIPGuid = EFI_LOADED_IMAGE_PROTOCOL_GUID;
    PEFI_LOADED_IMAGE_PROTOCOL LoadedImage;
    EFI_STATUS Status;

    /* Handle loaded image protocol */
    Status = EfiSystemTable->BootServices->HandleProtocol(EfiImageHandle, &LIPGuid, (PVOID *)&LoadedImage);
    if(Status == STATUS_EFI_SUCCESS)
    {
        /* Check if launched from UEFI shell */
        if(LoadedImage && LoadedImage->LoadOptions)
        {
            /* Update global boot loader configuration */
            BlpUpdateGlobalConfiguration(LoadedImage->LoadOptions);
        }
    }
}

/**
 * Updates XTLDR configuration based on provided options.
 *
 * @param Options
 *        Supplies a formatted list of options to be processed and stored in global configuration.
 *
 * @return This routine does not return any value.
 *
 * @since XT 1.0
 */
XTCDECL
VOID
BlpUpdateGlobalConfiguration(IN PWCHAR Options)
{
    PWCHAR Argument, LastArg;
    SIZE_T Length;

    /* Tokenize provided options */
    Argument = RtlTokenizeWideString(Options, L" ", &LastArg);

    /* Iterate over all arguments passed to boot loader */
    while(Argument != NULL)
    {
        /* Check all provided parameters */
        if(RtlCompareWideStringInsensitive(Argument, L"DEFAULT=", 8) == 0)
        {
            /* Skip to the argument value and calculate argument length */
            Argument += 8;
            Length = RtlWideStringLength(Argument, 0);

            /* Save default OS parameter in global configuration */
            BlMemoryAllocatePool(Length, (PVOID *)&BlpConfiguration.Default);
            RtlCopyMemory(BlpConfiguration.Default, Argument, (Length * sizeof(WCHAR)));
            BlpConfiguration.Default[Length] = '\0';
        }
        else if(RtlCompareWideStringInsensitive(Argument, L"DEBUG=", 6) == 0)
        {
            /* Skip to the argument value */
            Argument += 6;
            Length = RtlWideStringLength(Argument, 0);

            /* Store debug port configuration if not set already */
            if(BlpConfiguration.Debug == NULL)
            {
                /* Save debug port in global configuration */
                BlMemoryAllocatePool(Length, (PVOID *)&BlpConfiguration.Debug);
                RtlCopyMemory(BlpConfiguration.Debug, Argument, (Length * sizeof(WCHAR)));
                BlpConfiguration.Debug[Length] = '\0';
            }
        }
        else if(RtlCompareWideStringInsensitive(Argument, L"SHELL", 5) == 0)
        {
            /* Force shell mode */
            BlpConfiguration.Shell = TRUE;
        }
        else if(RtlCompareWideStringInsensitive(Argument, L"TIMEOUT=", 8) == 0)
        {
            /* Skip to the argument value */
            Argument += 8;

            /* Zero the timeout */
            BlpConfiguration.Timeout = 0;

            /* Read the timeout value and store it in global configuration */
            while(*Argument >= '0' && *Argument <= '9')
            {
                BlpConfiguration.Timeout *= 10;
                BlpConfiguration.Timeout += *Argument - '0';
                Argument++;
            }
        }
        else if(RtlCompareWideStringInsensitive(Argument, L"TUNE=", 5) == 0)
        {
            /* Skip to the argument value */
            Argument += 5;
            Length = RtlWideStringLength(Argument, 0);

            /* Save theme in global configuration */
            BlMemoryAllocatePool(Length, (PVOID *)&BlpConfiguration.Tune);
            RtlCopyMemory(BlpConfiguration.Tune, Argument, (Length * sizeof(WCHAR)));
            BlpConfiguration.Tune[Length] = '\0';
        }

        /* Take next argument */
        Argument = RtlTokenizeWideString(NULL, L" ", &LastArg);
    }
}