/*****************************************************************************************
 Copyright (c) 2002, 2016 The UbixOS Project
 All rights reserved.

 Redistribution and use in source and binary forms, with or without modification, are
 permitted provided that the following conditions are met:

 Redistributions of source code must retain the above copyright notice, this list of
 conditions, the following disclaimer and the list of authors.  Redistributions in binary
 form must reproduce the above copyright notice, this list of conditions, the following
 disclaimer and the list of authors in the documentation and/or other materials provided
 with the distribution. Neither the name of the UbixOS Project nor the names of its
 contributors may be used to endorse or promote products derived from this software
 without specific prior written permission.

 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
 EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 $Id: file.c 169 2016-01-20 01:10:22Z reddawg $

 *****************************************************************************************/

#include <vfs/vfs.h>
#include <vfs/file.h>
#include <ubixos/sched.h>
#include <ubixos/vitals.h>
#include <ubixos/kpanic.h>
#include <ubixos/spinlock.h>
#include <lib/kmalloc.h>
#include <lib/string.h>
#include <vmm/paging.h>
#include <lib/kprintf.h>
#include <assert.h>

static struct spinLock fdTable_lock = SPIN_LOCK_INITIALIZER;

fileDescriptor *fdTable = 0x0;

int sys_fwrite( struct thread *td, struct sys_fwrite_args *uap ) {
  char *t = uap->buf;

  kprintf( "uap->size: %i, FD: [0x%X], BUF: [0x%X][%c]\n", uap->nbytes, uap->fd, uap->buf, t[0] );

  if ( uap->fd == 0x0 )
    tty_print( (char *) uap->buf, _current->term );
  else
    fwrite( uap->buf, uap->nbytes, 1, uap->fd->fd );

  td->td_retval[0] = 0x0;

  return (0);
}

/* USER */

void sysFwrite( char *ptr, int size, userFileDescriptor *userFd ) {
  if ( userFd == 0x0 ) {
    tty_print( ptr, _current->term );
  }
  else {
    fwrite( ptr, size, 1, userFd->fd );
  }
  return;
}

int sys_fgetc( struct thread *td, struct sys_fgetc_args *args ) {
  char c;

  if ( args->FILE->fd == 0x0 ) {

    while ( 1 ) {

      if ( _current->term == tty_foreground ) {
        c = getchar();

        if ( c != 0x0 ) {
          td->td_retval[0] = c;
          return (0);
        }

        sched_yield();

      }
      else {
        sched_yield();
      }
      /*
       else {
       kprintf("Waking Task: %i\n",tty_foreground->owner);
       sched_setStatus(tty_foreground->owner,READY);
       kprintf("Sleeping Task: %i\n",_current->id);
       sched_setStatus(_current->id,WAIT);
       sched_yield();
       }
       */
    }
  }
  else {
    c = fgetc( args->FILE->fd );
    td->td_retval[0] = c;
    return (0);
  }
}

void sysRmDir() {
  return;
}

//int sys_fseek(userFileDescriptor *userFd,long offset,int whence) {
int sys_fseek( struct thread *td, struct sys_fseek_args *args ) {
  // TODO : coredump?
  if ( args->FILE == NULL ) {
    td->td_retval[0] = -1;
    return (-1);
  }

  if ( args->FILE->fd == NULL ) {
    td->td_retval[0] = -1;
    return (-1);
  }

  args->FILE->fd->offset = args->offset + args->whence;
  return (0);
}

int sys_chdir( struct thread *td, struct sys_chdir_args *args ) {
  if ( strstr( args->path, ":" ) == 0x0 ) {
    sprintf( _current->oInfo.cwd, "%s%s", _current->oInfo.cwd, args->path );
  }
  else {
    sprintf( _current->oInfo.cwd, args->path );
  }
  return (0);
}

int sysUnlink( const char *path, int *retVal ) {
  *retVal = unlink( path );
  return (*retVal);
}

/************************************************************************

 Function: void sysFopen();
 Description: Opens A File Descriptor For A User Task
 Notes:

 ************************************************************************/
//void sysFopen(const char *file,char *flags,userFileDescriptor *userFd) {
int sys_fopen( struct thread *td, struct sys_fopen_args *args ) {
  if ( args->FILE == NULL ) {
    kprintf( "Error: userFd == NULL, File: %s, Line: %i\n", __FILE__, __LINE__ );
    return (-1);
  }

  args->FILE->fd = fopen( args->path, args->mode );
  if ( args->FILE->fd != 0x0 ) {
    args->FILE->fdSize = args->FILE->fd->size;
  }
  /* Return */
  return (0);
}

/************************************************************************

 Function: void sysFread();
 Description: Reads SIZE Bytes From The userFd Into DATA
 Notes:

 ************************************************************************/
int sys_fread( struct thread *td, struct sys_fread_args *args ) {
//void *data,long size,userFileDescriptor *userFd) {

  /* TODO : coredump? */
  if ( args->FILE == NULL )
    return (-1);

  if ( args->FILE->fd == NULL )
    return (-1);

  return (fread( args->ptr, args->size, args->nmemb, args->FILE->fd ));
}

/************************************************************************

 Function: void sysFclse();
 Description: Closes A File Descriptor For A User Task
 Notes:

 ************************************************************************/
int sys_fclose( struct thread *td, struct sys_fclose_args *args ) {
  if ( args->FILE == NULL ) {
    return (-1);
  }
  if ( args->FILE == NULL ) {
    return (-1);
  }

  /* Return */
  return (fclose( args->FILE ));
}

/* KERNEL */

size_t fread( void *ptr, size_t size, size_t nmemb, fileDescriptor *fd ) {
  size_t i = 0x0;

  if ( fd == 0x0 )
    return (0x0);

  if ( nmemb == 0x0 )
    nmemb = 1; //Temp Fix

  assert( fd );
  assert( fd->mp );
  assert( fd->mp->fs );

  i = fd->mp->fs->vfsRead( fd, ptr, fd->offset, size * nmemb );

  fd->offset += size * nmemb;

  //kprintf("fread: %i:%i",i,size *nmemb);

  return (i);
}

size_t fwrite( void *ptr, int size, int nmemb, fileDescriptor *fd ) {
  if ( fd != 0x0 ) {
    fd->mp->fs->vfsWrite( fd, ptr, fd->offset, size * nmemb );
    fd->offset += size * nmemb;
  }
  return (0x0);
}

int fseek( fileDescriptor *tmpFd, long offset, int whence ) {
  tmpFd->offset = offset + whence;
  return (tmpFd->offset);
}

/************************************************************************

 Function: int feof(fileDescriptor *fd)
 Description: Check A File Descriptor For EOF And Return Result
 Notes:

 ************************************************************************/
int feof( fileDescriptor *fd ) {
  if ( fd->status == fdEof ) {
    return (-1);
  }
  return (0);
}

/************************************************************************

 Function: int fputc(int ch,fileDescriptor *fd)
 Description: This Will Write Character To FD
 Notes:

 ************************************************************************/
int fputc( int ch, fileDescriptor *fd ) {
  if ( fd != 0x0 ) {
    ch = fd->mp->fs->vfsWrite( fd, (char *) ch, fd->offset, 1 );
    fd->offset++;
    return (ch);
  }
  /* Return NULL If FD Is Not Found */
  return (0x0);
}

/************************************************************************

 Function: int fgetc(fileDescriptor *fd)
 Description: This Will Return The Next Character In A FD Stream
 Notes:

 ************************************************************************/
int fgetc( fileDescriptor *fd ) {
  int ch = 0x0;
  /* If Found Return Next Char */
  if ( fd != 0x0 ) {
    fd->mp->fs->vfsRead( fd, (char *) &ch, fd->offset, 1 );
    fd->offset++;
    return (ch);
  }

  /* Return NULL If FD Is Not Found */
  return (0x0);
}

/************************************************************************

 Function: fileDescriptor *fopen(const char *file,cont char *flags)
 Description: This Will Open A File And Return A File Descriptor
 Notes:

 08/05/02 - Just Started A Rewrite Of This Function Should Work Out Well

 ************************************************************************/

fileDescriptor *fopen( const char *file, const char *flags ) {
  int i = 0x0;
  char *path = 0x0;
  char *mountPoint = 0x0;
  char fileName[1024];
  fileDescriptor *tmpFd = 0x0;

  /* Allocate Memory For File Descriptor */
  if ( (tmpFd = (fileDescriptor *) kmalloc( sizeof(fileDescriptor) )) == 0x0 ) {
    kprintf( "Error: tmpFd == NULL, File: %s, Line: %i\n", __FILE__, __LINE__ );
    return (NULL);
  }

  strcpy( fileName, file );

  if ( strstr( fileName, ":" ) ) {
    mountPoint = (char *) strtok( (char *) &fileName, ":" );
    path = strtok( NULL, "\n" );
  }
  else {
    path = fileName;
  }

  if ( path[0] == '/' )
    strcpy( tmpFd->fileName, path );
  else
    sprintf( tmpFd->fileName, "/%s", path );

  /* Find our mount point or set default to sys */
  if ( mountPoint == 0x0 )
    tmpFd->mp = vfs_findMount( "sys" );
  else
    tmpFd->mp = vfs_findMount( mountPoint );

  if ( tmpFd->mp == 0x0 ) {
    kprintf( "Mount Point Bad\n" );
    return (0x0);
  }

  /* This Will Set Up The Descriptor Modes */
  tmpFd->mode = 0;
  for ( i = 0; '\0' != flags[i]; i++ ) {
    switch ( flags[i] ) {
      case 'w':
        case 'W':
        tmpFd->mode |= fileWrite;
        break;
      case 'r':
        case 'R':
        tmpFd->mode |= fileRead;
        break;
      case 'b':
        case 'B':
        tmpFd->mode |= fileBinary;
        break;
      case 'a':
        case 'A':
        tmpFd->mode |= fileAppend;
        break;
      default:
        kprintf( "Invalid mode '%c' for fopen\n", flags[i] );
        break;
    }
  }
  /* Search For The File */
  if ( tmpFd->mp->fs->vfsOpenFile( tmpFd->fileName, tmpFd ) == 0x1 ) {
    /* If The File Is Found Then Set Up The Descriptor */

    /* in order to save resources we will allocate the buffer later when it is needed */

    tmpFd->buffer = (char *) kmalloc( 4096 );
    if ( tmpFd->buffer == 0x0 )
        {
      kfree( tmpFd );
      kprintf( "Error: tmpFd->buffer == NULL, File: %s, Line: %i\n", __FILE__, __LINE__ );
      spinUnlock( &fdTable_lock );
      return 0x1;
    }
    /* Set Its Status To Open */
    tmpFd->status = fdOpen;

    /* Initial File Offset Is Zero */
    tmpFd->offset = 0;
    tmpFd->prev = 0x0;

    /* we do not want to be in a spinlock longer than we need to, so
     it has been moved to here. */
    spinLock( &fdTable_lock );

    /* Increment Number Of Open Files */
    systemVitals->openFiles++;

    tmpFd->next = fdTable;

    if ( fdTable != 0x0 )
      fdTable->prev = tmpFd;

    fdTable = tmpFd;

    spinUnlock( &fdTable_lock );

    /* Return The FD */
    return (tmpFd);
  }
  else {
    kfree( tmpFd->buffer );
    kfree( tmpFd );
    spinUnlock( &fdTable_lock );
    //MrOlsen (2016-01-13) NOTE: We don't need this right now kprintf("File Not Found? %s\n",file);
    return (NULL);
  }

  /* Return NULL */
  return (0x0);
}

/************************************************************************

 Function: int fclose(fileDescriptor *fd);
 Description: This Will Close And Free A File Descriptor
 Notes:

 ************************************************************************/
int fclose( fileDescriptor *fd ) {
  fileDescriptor *tmpFd = 0x0;
  assert( fd );

  spinLock( &fdTable_lock );

  for ( tmpFd = fdTable; tmpFd != 0x0; tmpFd = tmpFd->next ) {
    if ( tmpFd == fd ) {
      if ( tmpFd->prev )
        tmpFd->prev->next = tmpFd->next;
      if ( tmpFd->next )
        tmpFd->next->prev = tmpFd->prev;

      if ( tmpFd == fdTable )
        fdTable = tmpFd->next;

      systemVitals->openFiles--;
      spinUnlock( &fdTable_lock );
      if ( tmpFd->buffer != NULL )
        kfree( tmpFd->buffer );
      kfree( tmpFd );
      return (0x0);
    }
  }

  spinUnlock( &fdTable_lock );
  return (0x1);
}

/* UBU */

/************************************************************************

 Function: void sysMkDir(const char *path)
 Description: This Will Create A New Directory
 Notes:

 ************************************************************************/
void sysMkDir( const char *path ) {
  fileDescriptor *tmpFD = 0x0;
  char tmpDir[1024];
  char rootPath[256];
  char *dir = 0x0; //UBU*mountPoint = 0x0;
  char *tmp = 0x0;
  rootPath[0] = '\0';
  dir = (char *) path;

  if ( strstr( path, ":" ) == 0x0 ) {
    sprintf( tmpDir, "%s%s", _current->oInfo.cwd, path );
    dir = (char *) &tmpDir;
  }
  while ( strstr( dir, "/" ) ) {
    if ( rootPath[0] == 0x0 )
      sprintf( rootPath, "%s/", strtok( dir, "/" ) );
    else
      sprintf( rootPath, "%s%s/", rootPath, strtok( dir, "/" ) );
    tmp = strtok( NULL, "\n" );
    dir = tmp;
  }

  //kprintf("rootPath: [%s]\n",rootPath);
  tmpFD = fopen( rootPath, "rb" );

  if ( tmpFD->mp == 0x0 ) {
    kprintf( "Invalid Mount Point\n" );
  }
  tmpFD->mp->fs->vfsMakeDir( dir, tmpFD );

  fclose( tmpFD );

  return;
}

/************************************************************************

 Function: int unlink(const char *node)
 Description: This will unlink a file
 Notes:

 ************************************************************************/

int unlink( const char *node ) {
  char *path = 0x0, *mountPoint = 0x0;
  struct vfs_mountPoint *mp = 0x0;

  path = (char *) strtok( (char *) node, "@" );
  mountPoint = strtok( NULL, "\n" );
  if ( mountPoint == 0x0 ) {
    mp = vfs_findMount( "sys" ); /* _current->oInfo.container; */
  }
  else {
    mp = vfs_findMount( mountPoint );
  }
  if ( mp == 0x0 ) {
    //kpanic("Mount Point Bad");
    return (0x0);
  }
  mp->fs->vfsUnlink( path, mp );
  return (0x0);
}

/***
 END
 ***/