/* ========================================

  Copyright (C) 2024-2025, Amlal El Mahrouss, licensed under the Apache 2.0 license.

  File: FileReader.cc
  Purpose: New Boot FileReader,
  Read complete file and store it in a buffer.

======================================== */

#include <BootKit/BootKit.h>
#include <BootKit/Platform.h>
#include <BootKit/Protocol.h>
#include <FirmwareKit/EFI/API.h>
#include <FirmwareKit/Handover.h>
#include <modules/CoreGfx/TextGfx.h>

/// @file BootFileReader
/// @brief Bootloader File reader.
/// BUGS: 0

////////////////////////////////////////////////////////////////////////////////////////////////////
///
///
///  @name BootFileReader class
///  @brief Reads the file as a blob.
///
///
////////////////////////////////////////////////////////////////////////////////////////////////////

/***
  @brief File Reader constructor.
*/
Boot::BootFileReader::BootFileReader(const CharacterTypeUTF16* path, EfiHandlePtr ImageHandle) {
  if (path != nullptr) {
    SizeT index = 0UL;
    for (; path[index] != L'\0'; ++index) {
      mPath[index] = path[index];
    }

    mPath[index] = 0;
  }

  /// Load protocols with their GUIDs.

  EFI_GUID guidEfp = EFI_GUID(EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID);

  EfiSimpleFilesystemProtocol* efp = nullptr;

  EfiLoadImageProtocol* img     = nullptr;
  EFI_GUID              guidImg = EFI_GUID(EFI_LOADED_IMAGE_PROTOCOL_GUID);

  if (BS->HandleProtocol(ImageHandle, &guidImg, (void**) &img) != kEfiOk) {
    mWriter.Write(L"BootZ: Handle-Protocol: No-Such-Protocol").Write(L"\r");
    this->mErrorCode = kNotSupported;
  }

  if (BS->HandleProtocol(img->DeviceHandle, &guidEfp, (void**) &efp) != kEfiOk) {
    mWriter.Write(L"BootZ: Handle-Protocol: No-Such-Protocol").Write(L"\r");
    this->mErrorCode = kNotSupported;
    return;
  }

  /// Start doing disk I/O

  if (efp->OpenVolume(efp, &mRootFs) != kEfiOk) {
    mWriter.Write(L"BootZ: Fetch-Protocol: No-Such-Volume").Write(L"\r");
    this->mErrorCode = kNotSupported;
    return;
  }

  EfiFileProtocol* fileFs = nullptr;

  if (mRootFs->Open(mRootFs, &fileFs, mPath, kEFIFileRead, kEFIReadOnly) != kEfiOk) {
    mWriter.Write(L"BootZ: Fetch-Protocol: No-Such-Path: ").Write(mPath).Write(L"\r");
    this->mErrorCode = kNotSupported;

    cg_render_string("BootZ: PLEASE RECOVER YOUR NEKERNEL INSTALL.", 40, 10, RGB(0xFF, 0xFF, 0xFF));

    mRootFs->Close(mRootFs);

    return;
  }

  mSizeFile  = 0;
  mFile      = fileFs;
  mErrorCode = kOperationOkay;
}

Boot::BootFileReader::~BootFileReader() {
  if (this->mFile) {
    this->mFile->Close(this->mFile);
    this->mFile = nullptr;
  }

  if (this->mRootFs) {
    this->mRootFs->Close(this->mRootFs);
    this->mRootFs = nullptr;
  }

  if (this->mBlob) {
    BS->FreePool(this->mBlob);
    this->mBlob = nullptr;
  }

  BSetMem(this->mPath, 0, kPathLen);
}

/**
  @brief Reads all of the file into a buffer.
  @param **readUntil** size of file
  @param **chunkToRead** chunk to read each time.
*/
Void Boot::BootFileReader::ReadAll(SizeT readUntil, SizeT chunkToRead, UIntPtr out_address) {
  UInt32 szInfo = sizeof(EfiFileInfo);

  EfiFileInfo newPtrInfo{};

  EFI_GUID kFileInfoGUID = EFI_FILE_INFO_GUID;

  if (mFile->GetInfo(mFile, &kFileInfoGUID, &szInfo, &newPtrInfo) == kEfiOk) {
    readUntil = newPtrInfo.FileSize;
    mWriter.Write(L"BootZ: File size: ").Write(readUntil).Write("\r");
  }

  if (readUntil == 0) {
    mErrorCode = kNotSupported;
    return;
  }

  if (mBlob == nullptr) {
    if (!out_address) {
      if (auto err = BS->AllocatePool(EfiLoaderCode, readUntil, (VoidPtr*) &mBlob) != kEfiOk) {
        mWriter.Write(L"*** error: ").Write(err).Write(L" ***\r");
        Boot::ThrowError(L"OutOfMemory", L"Out of memory.");
      }
    } else {
      mBlob = (VoidPtr) out_address;
    }
  }

  mWriter.Write(L"*** Bytes to read: ").Write(readUntil).Write(L" ***\r");

  UInt64 bufSize = chunkToRead;
  UInt64 szCnt   = 0UL;

  while (szCnt < readUntil) {
    auto res = mFile->Read(mFile, &bufSize, (VoidPtr) (&((Char*) mBlob)[szCnt]));

    szCnt += bufSize;

    if (res == kBufferTooSmall) {
      bufSize = chunkToRead;
    }
  }

  mSizeFile  = szCnt;
  mErrorCode = kOperationOkay;
}

/// @brief error code getter.
/// @return the error code.
Int32& Boot::BootFileReader::Error() {
  return mErrorCode;
}

/// @brief blob getter.
/// @return the blob.
VoidPtr Boot::BootFileReader::Blob() {
  return mBlob;
}

/// @breif Size getter.
/// @return the size of the file.
UInt64& Boot::BootFileReader::Size() {
  return mSizeFile;
}