/** @file
  Abstract device driver for the UEFI Shell-hosted environment.

  In a Shell-hosted environment, this is the driver that is called
  when no other driver matches.

  Copyright (c) 2011, Intel Corporation. All rights reserved.<BR>
  This program and the accompanying materials are licensed and made available under
  the terms and conditions of the BSD License that accompanies this distribution.
  The full text of the license may be found at
  http://opensource.org/licenses/bsd-license.

  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/
#include  <Uefi.h>
#include  <Library/BaseLib.h>
#include  <Library/MemoryAllocationLib.h>
#include  <Library/UefiBootServicesTableLib.h>
#include  <Library/ShellLib.h>

#include  <LibConfig.h>
#include  <sys/EfiSysCall.h>

#include  <errno.h>
#include  <string.h>
#include  <stdlib.h>
#include  <wctype.h>
#include  <wchar.h>
#include  <sys/fcntl.h>
#include  <kfile.h>
#include  <Device/Device.h>
#include  <MainData.h>
#include  <Efi/SysEfi.h>

static
int
EFIAPI
da_ShellClose(
  IN      struct __filedes   *Fp
)
{
  EFIerrno = ShellCloseFile( (SHELL_FILE_HANDLE *)&Fp->devdata);
  if(RETURN_ERROR(EFIerrno)) {
    return -1;
  }
  return 0;
}

static
int
EFIAPI
da_ShellDelete(
  struct __filedes   *filp
  )
{
  RETURN_STATUS         Status;

  Status = ShellDeleteFile( (SHELL_FILE_HANDLE *)&filp->devdata);
  if(Status != RETURN_SUCCESS) {
    errno = EFI2errno(Status);
    EFIerrno = Status;
    return -1;
  }
  return 0;
}

static
off_t
EFIAPI
da_ShellSeek(
  struct __filedes   *filp,
  off_t               offset,
  int                 whence
)
{
  __off_t             CurPos = -1;
  RETURN_STATUS       Status = RETURN_SUCCESS;
  SHELL_FILE_HANDLE   FileHandle;

  FileHandle = (SHELL_FILE_HANDLE)filp->devdata;

  if(whence != SEEK_SET) {
    // We are doing a relative seek
    if(whence == SEEK_END) {
      // seeking relative to EOF, so position there first.
      Status = ShellSetFilePosition( FileHandle, 0xFFFFFFFFFFFFFFFFULL);
    }
    if(Status == RETURN_SUCCESS) {
      // Now, determine our current position.
      Status = ShellGetFilePosition( FileHandle, (UINT64 *)&CurPos);
    }
  }
  else {
    CurPos = 0;   // offset is an absolute position for SEEK_SET
    if(offset < 0) {
      Status = RETURN_INVALID_PARAMETER;
    }
  }
  if(Status == RETURN_SUCCESS) {
    /* CurPos now indicates the point we are seeking from, so seek... */
    Status = ShellSetFilePosition( FileHandle, (UINT64)(CurPos + offset));
    if(Status == RETURN_SUCCESS) {
      // Now, determine our final position.
      Status = ShellGetFilePosition( FileHandle, (UINT64 *)&CurPos);
    }
  }
  if(Status != RETURN_SUCCESS) {
    if(Status == EFI_UNSUPPORTED) {
      errno = EISDIR;
    }
    else {
      errno = EFI2errno(Status);
    }
    EFIerrno = Status;
    CurPos = EOF;
  }
  return CurPos;
}

/** The directory path is created with the access permissions specified by
    perms.

    The directory is closed after it is created.

    @retval   0   The directory was created successfully.
    @retval  -1   An error occurred and an error code is stored in errno.
**/
static
int
EFIAPI
da_ShellMkdir(
  const char   *path,
  __mode_t      perms
  )
{
  SHELL_FILE_HANDLE FileHandle;
  RETURN_STATUS     Status;
  EFI_FILE_INFO    *FileInfo;
  wchar_t          *NewPath;
  int               retval = -1;

  // Convert name from MBCS to WCS and change '/' to '\\'
  NewPath = NormalizePath( path);

  if(NewPath != NULL) {
    Status = ShellCreateDirectory( NewPath, &FileHandle);
    if(Status == RETURN_SUCCESS) {
      FileInfo = ShellGetFileInfo( FileHandle);
      Status = RETURN_ABORTED;  // In case ShellGetFileInfo() failed
      if(FileInfo != NULL) {
        FileInfo->Attribute = Omode2EFI(perms);
        Status = ShellSetFileInfo( FileHandle, FileInfo);
        FreePool(FileInfo);
        if(Status == RETURN_SUCCESS) {
          (void)ShellCloseFile(&FileHandle);
          retval = 0;
        }
      }
    }
    errno = EFI2errno(Status);
    EFIerrno = Status;
    free(NewPath);
  }
  return retval;
}

static
ssize_t
EFIAPI
da_ShellRead(
  IN OUT  struct __filedes   *filp,
  IN OUT  off_t              *offset,
  IN      size_t              BufferSize,
     OUT  VOID               *Buffer
)
{
  ssize_t           BufSize;
  SHELL_FILE_HANDLE FileHandle;
  RETURN_STATUS     Status;

  if(offset != NULL) {
    BufSize = (ssize_t)da_ShellSeek(filp, *offset, SEEK_SET);
    if(BufSize >= 0) {
      filp->f_offset = BufSize;
    }
  }

  BufSize = (ssize_t)BufferSize;
  FileHandle = (SHELL_FILE_HANDLE)filp->devdata;

  Status = ShellReadFile( FileHandle, (UINTN *)&BufSize, Buffer);
  if(Status != RETURN_SUCCESS) {
    EFIerrno = Status;
    errno = EFI2errno(Status);
    if(Status == RETURN_BUFFER_TOO_SMALL) {
      BufSize = -BufSize;
    }
    else {
      BufSize = -1;
    }
  }
  else {
    filp->f_offset += BufSize;  // Advance to where we want to read next.
  }
  return BufSize;
}

static
ssize_t
EFIAPI
da_ShellWrite(
  IN  struct __filedes     *filp,
  IN  off_t                *offset,
  IN  size_t                BufferSize,
  IN  const void           *Buffer
  )
{
  ssize_t           BufSize;
  SHELL_FILE_HANDLE FileHandle;
  RETURN_STATUS     Status;
  off_t             Position  = 0;
  int               How       = SEEK_SET;


  if((offset != NULL) || (filp->Oflags & O_APPEND)) {
    if(filp->Oflags & O_APPEND) {
      Position  = 0;
      How       = SEEK_END;
    }
    else {
      Position  = *offset;
      How       = SEEK_SET;
    }
    BufSize = (ssize_t)da_ShellSeek(filp, Position, How);
    if(BufSize >= 0) {
      filp->f_offset = BufSize;
    }
  }

  BufSize = (ssize_t)BufferSize;
  FileHandle = (SHELL_FILE_HANDLE)filp->devdata;

  Status = ShellWriteFile( FileHandle, (UINTN *)&BufSize, (void *)Buffer);

  if(Status != RETURN_SUCCESS) {
    EFIerrno = Status;
    errno = EFI2errno(Status);
    if(Status == EFI_UNSUPPORTED) {
      errno = EISDIR;
    }
    BufSize = -1;
  }
  else {
    filp->f_offset += BufSize;  // Advance to where we want to write next.
  }

  return BufSize;
}

static
int
EFIAPI
da_ShellStat(
  struct __filedes   *filp,
  struct stat        *statbuf,
  void               *Something
  )
{
  SHELL_FILE_HANDLE FileHandle;
  EFI_FILE_INFO    *FileInfo      = NULL;
  UINT64            Attributes;
  RETURN_STATUS     Status;
  mode_t            newmode;

  FileHandle = (SHELL_FILE_HANDLE)filp->devdata;

  FileInfo = ShellGetFileInfo( FileHandle);

  if(FileInfo != NULL) {
    // Got the info, now populate statbuf with it
    statbuf->st_blksize   = S_BLKSIZE;
    statbuf->st_size      = FileInfo->FileSize;
    statbuf->st_physsize  = FileInfo->PhysicalSize;
    statbuf->st_birthtime = Efi2Time( &FileInfo->CreateTime);
    statbuf->st_atime     = Efi2Time( &FileInfo->LastAccessTime);
    statbuf->st_mtime     = Efi2Time( &FileInfo->ModificationTime);
    Attributes = FileInfo->Attribute;
    newmode               = (mode_t)(Attributes << S_EFISHIFT) | S_ACC_READ;
    if((Attributes & EFI_FILE_DIRECTORY) == 0) {
      newmode |= _S_IFREG;
      if((Attributes & EFI_FILE_READ_ONLY) == 0) {
        newmode |= S_ACC_WRITE;
      }
    }
    else {
      newmode |= _S_IFDIR;
    }
    statbuf->st_mode = newmode;
    Status = RETURN_SUCCESS;
  }
  else {
    Status = RETURN_DEVICE_ERROR;
  }
  errno     = EFI2errno(Status);
  EFIerrno  = Status;

  if(FileInfo != NULL) {
    FreePool(FileInfo);     // Release the buffer allocated by the GetInfo function
  }
  return errno? -1 : 0;
}

static
int
EFIAPI
da_ShellIoctl(
  struct __filedes   *filp,
  ULONGN              cmd,
  void               *argp       ///< May be a pointer or a value
  )
{
  return 0;
}

/** Open an abstract Shell File.
**/
int
EFIAPI
da_ShellOpen(
  struct __filedes   *filp,
  void               *DevInstance,
  wchar_t            *Path,
  wchar_t            *Flags
  )
{
  UINT64                OpenMode;
  UINT64                Attributes;
  SHELL_FILE_HANDLE     FileHandle;
  GenericInstance      *Gip;
  char                 *NPath;
  RETURN_STATUS         Status;
  int                   oflags;

  EFIerrno = RETURN_SUCCESS;

  //Attributes = Omode2EFI(mode);
  Attributes = 0;

  // Convert oflags to Attributes
  oflags = filp->Oflags;
  OpenMode = Oflags2EFI(oflags);
  if(OpenMode == 0) {
    errno = EINVAL;
    return -1;
  }

  /* Do we care if the file already exists?
     If O_TRUNC, then delete the file.  It will be created anew subsequently.
     If O_EXCL, then error if the file exists and O_CREAT is set.

  !!!!!!!!! Change this to use ShellSetFileInfo() to actually truncate the file
  !!!!!!!!! instead of deleting and re-creating it.
  */
  if((oflags & O_TRUNC) || ((oflags & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT))) {
    Status = ShellIsFile( Path );
    if(Status == RETURN_SUCCESS) {
      // The file exists
      if(oflags & O_TRUNC) {
        NPath = AllocateZeroPool(1024);
        if(NPath == NULL) {
          errno = ENOMEM;
          EFIerrno = RETURN_OUT_OF_RESOURCES;
          return -1;
        }
        wcstombs(NPath, Path, 1024);
        // We do a truncate by deleting the existing file and creating a new one.
        if(unlink(NPath) != 0) {
          filp->f_iflags = 0;    // Release our reservation on this FD
          FreePool(NPath);
          return -1;  // errno and EFIerrno are already set.
        }
        FreePool(NPath);
      }
      else if((oflags & (O_EXCL | O_CREAT)) == (O_EXCL | O_CREAT)) {
        errno = EEXIST;
        EFIerrno = RETURN_ACCESS_DENIED;
        filp->f_iflags = 0;    // Release our reservation on this FD
        return -1;
      }
    }
  }

  // Call the EFI Shell's Open function
  Status = ShellOpenFileByName( Path, &FileHandle, OpenMode, Attributes);
  if(RETURN_ERROR(Status)) {
    filp->f_iflags = 0;    // Release our reservation on this FD
    // Set errno based upon Status
    errno = EFI2errno(Status);
    EFIerrno = Status;
    return -1;
  }
  // Successfully got a regular File
  filp->f_iflags |= S_IFREG;

  // Update the info in the fd
  filp->devdata = (void *)FileHandle;

  Gip = (GenericInstance *)DevInstance;
  filp->f_offset = 0;
  filp->f_ops = &Gip->Abstraction;
//  filp->devdata = FileHandle;

  return 0;
}

#include  <sys/poll.h>
/*  Returns a bit mask describing which operations could be completed immediately.

    For now, assume the file system, via the shell, is always ready.

    (POLLIN | POLLRDNORM)   The file system is ready to be read.
    (POLLOUT)               The file system is ready for output.

*/
static
short
EFIAPI
da_ShellPoll(
  struct __filedes   *filp,
  short               events
  )
{
  UINT32      RdyMask;
  short       retval = 0;

  RdyMask = (UINT32)filp->Oflags;

  switch(RdyMask & O_ACCMODE) {
    case O_RDONLY:
      retval = (POLLIN | POLLRDNORM);
      break;

    case O_WRONLY:
      retval = POLLOUT;
      break;

    case O_RDWR:
      retval = (POLLIN | POLLRDNORM | POLLOUT);
      break;

    default:
      retval = POLLERR;
      break;
  }
  return (retval & (events | POLL_RETONLY));
}

static
int
EFIAPI
da_ShellRename(
  const char   *from,
  const char   *to
  )
{
  RETURN_STATUS       Status;
  EFI_FILE_INFO      *NewFileInfo;
  EFI_FILE_INFO      *OldFileInfo;
  char               *NewFn;
  int                 OldFd;
  SHELL_FILE_HANDLE   FileHandle;

  // Open old file
  OldFd = open(from, O_RDWR, 0);
  if(OldFd >= 0) {
    FileHandle = (SHELL_FILE_HANDLE)gMD->fdarray[OldFd].devdata;

    NewFileInfo = malloc(sizeof(EFI_FILE_INFO) + PATH_MAX);
    if(NewFileInfo != NULL) {
      OldFileInfo = ShellGetFileInfo( FileHandle);
      if(OldFileInfo != NULL) {
        // Copy the Old file info into our new buffer, and free the old.
        memcpy(OldFileInfo, NewFileInfo, sizeof(EFI_FILE_INFO));
        FreePool(OldFileInfo);
        // Strip off all but the file name portion of new
        NewFn = strrchr(to, '/');
        if(NewFn == NULL) {
          NewFn = strrchr(to, '\\');
          if(NewFn == NULL) {
            NewFn = (char *)to;
          }
        }
        // Convert new name from MBCS to WCS
        (void)AsciiStrToUnicodeStr( NewFn, gMD->UString);
        // Copy the new file name into our new file info buffer
        wcsncpy(NewFileInfo->FileName, gMD->UString, wcslen(gMD->UString)+1);
        // Apply the new file name
        Status = ShellSetFileInfo(FileHandle, NewFileInfo);
        free(NewFileInfo);
        if(Status == EFI_SUCCESS) {
          // File has been successfully renamed.  We are DONE!
          return 0;
        }
        errno = EFI2errno( Status );
        EFIerrno = Status;
      }
      else {
        errno = EIO;
      }
    }
    else {
      errno = ENOMEM;
    }
  }
  return -1;
}

static
int
EFIAPI
da_ShellRmdir(
  struct __filedes   *filp
  )
{
  SHELL_FILE_HANDLE FileHandle;
  RETURN_STATUS     Status = RETURN_SUCCESS;
  EFI_FILE_INFO     *FileInfo = NULL;
  int               Count = 0;
  BOOLEAN           NoFile = FALSE;

  errno = 0;    // Make it easier to see if we have an error later

  FileHandle = (SHELL_FILE_HANDLE)filp->devdata;

  FileInfo = ShellGetFileInfo(FileHandle);
  if(FileInfo != NULL) {
    if((FileInfo->Attribute & EFI_FILE_DIRECTORY) == 0) {
      errno = ENOTDIR;
    }
    else {
      // See if the directory has any entries other than ".." and ".".
      FreePool(FileInfo);  // Free up the buffer from ShellGetFileInfo()
      Status = ShellFindFirstFile( FileHandle, &FileInfo);
      if(Status == RETURN_SUCCESS) {
        ++Count;
        while(Count < 3) {
          Status = ShellFindNextFile( FileHandle, FileInfo, &NoFile);
          if(Status == RETURN_SUCCESS) {
            if(NoFile) {
              break;
            }
            ++Count;
          }
          else {
            Count = 99;
          }
        }
        FreePool(FileInfo);   // Free buffer from ShellFindFirstFile()
        if(Count < 3) {
          // Directory is empty
          Status = ShellDeleteFile( &FileHandle);
          if(Status == RETURN_SUCCESS) {
            EFIerrno = RETURN_SUCCESS;
            return 0;
            /* ######## SUCCESSFUL RETURN ######## */
          }
        }
        else {
          if(Count == 99) {
            errno = EIO;
          }
          else {
            errno = ENOTEMPTY;
          }
        }
      }
    }
  }
  else {
    errno = EIO;
  }
  EFIerrno = Status;
  if(errno == 0) {
    errno = EFI2errno( Status );
  }
  return -1;
}

/** Construct an instance of the abstract Shell device.

    Allocate the instance structure and populate it with the information for
    the device.
**/
RETURN_STATUS
EFIAPI
__ctor_DevShell(
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
)
{
  GenericInstance    *Stream;
  DeviceNode     *Node;
  RETURN_STATUS   Status;

  Stream = (GenericInstance *)AllocateZeroPool(sizeof(GenericInstance));
  if(Stream == NULL) {
    return RETURN_OUT_OF_RESOURCES;
  }

  Stream->Cookie      = CON_COOKIE;
  Stream->InstanceNum = 1;
  Stream->Dev = NULL;
  Stream->Abstraction.fo_close    = &da_ShellClose;
  Stream->Abstraction.fo_read     = &da_ShellRead;
  Stream->Abstraction.fo_write    = &da_ShellWrite;
  Stream->Abstraction.fo_fcntl    = &fnullop_fcntl;
  Stream->Abstraction.fo_poll     = &da_ShellPoll;
  Stream->Abstraction.fo_flush    = &fnullop_flush;
  Stream->Abstraction.fo_stat     = &da_ShellStat;
  Stream->Abstraction.fo_ioctl    = &fbadop_ioctl;
  Stream->Abstraction.fo_delete   = &da_ShellDelete;
  Stream->Abstraction.fo_rmdir    = &da_ShellRmdir;
  Stream->Abstraction.fo_mkdir    = &da_ShellMkdir;
  Stream->Abstraction.fo_rename   = &da_ShellRename;
  Stream->Abstraction.fo_lseek    = &da_ShellSeek;

  Node = __DevRegister(NULL, NULL, &da_ShellOpen, Stream, 1, sizeof(GenericInstance), O_RDWR);
  Status = EFIerrno;
  Stream->Parent = Node;

  return  Status;
}

RETURN_STATUS
EFIAPI
__dtor_DevShell(
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
)
{
  if(daDefaultDevice != NULL) {
    if(daDefaultDevice->InstanceList != NULL) {
      FreePool(daDefaultDevice->InstanceList);
    }
    FreePool(daDefaultDevice);
  }
  return RETURN_SUCCESS;
}
