/*
 *  GRUB  --  GRand Unified Bootloader
 *  Copyright (C) 2002,2003,2005,2007,2008,2009  Free Software Foundation, Inc.
 *
 *  GRUB is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  GRUB is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <grub/term.h>
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/file.h>
#include <grub/dl.h>
#include <grub/env.h>
#include <grub/normal.h>

/* The amount of lines counted by the pager.  */
static unsigned grub_more_lines;

/* If the more pager is active.  */
static int grub_more;

static void
process_newline (void)
{
  struct grub_term_output *cur;
  unsigned height = -1;

  FOR_ACTIVE_TERM_OUTPUTS(cur)
    if (grub_term_height (cur) < height)
      height = grub_term_height (cur);
  grub_more_lines++;

  if (grub_more && grub_more_lines >= height - 1)
    {
      char key;
      grub_uint16_t *pos;

      pos = grub_term_save_pos ();

      grub_setcolorstate (GRUB_TERM_COLOR_HIGHLIGHT);
      grub_printf ("--MORE--");
      grub_setcolorstate (GRUB_TERM_COLOR_STANDARD);

      key = grub_getkey ();

      /* Remove the message.  */
      grub_term_restore_pos (pos);
      grub_printf ("        ");
      grub_term_restore_pos (pos);

      /* Scroll one lines or an entire page, depending on the key.  */
      if (key == '\r' || key =='\n')
	grub_more_lines = height - 2;
      else
	grub_more_lines = 0;
    }
}

void
grub_set_more (int onoff)
{
  if (onoff == 1)
    grub_more++;
  else
    grub_more--;

  grub_more_lines = 0;
  grub_newline_hook = process_newline;
}

void
grub_puts_terminal (const char *str, struct grub_term_output *term)
{
  grub_uint32_t code;
  grub_ssize_t ret;
  const grub_uint8_t *ptr = (const grub_uint8_t *) str;
  const grub_uint8_t *end;
  end = (const grub_uint8_t *) (str + grub_strlen (str));

  while (*ptr)
    {
      ret = grub_utf8_to_ucs4 (&code, 1, ptr, end - ptr, &ptr);
      grub_putcode (code, term);	
    }
}

grub_uint16_t *
grub_term_save_pos (void)
{
  struct grub_term_output *cur;
  unsigned cnt = 0;
  grub_uint16_t *ret, *ptr;
  
  FOR_ACTIVE_TERM_OUTPUTS(cur)
    cnt++;

  ret = grub_malloc (cnt * sizeof (ret[0]));
  if (!ret)
    return NULL;

  ptr = ret;
  FOR_ACTIVE_TERM_OUTPUTS(cur)
    *ptr++ = grub_term_getxy (cur);

  return ret;
}

void
grub_term_restore_pos (grub_uint16_t *pos)
{
  struct grub_term_output *cur;
  grub_uint16_t *ptr = pos;

  if (!pos)
    return;

  FOR_ACTIVE_TERM_OUTPUTS(cur)
  {
    grub_term_gotoxy (cur, (*ptr & 0xff00) >> 8, *ptr & 0xff);
    ptr++;
  }
}

static void 
grub_terminal_autoload_free (void)
{
  struct grub_term_autoload *cur, *next;
  unsigned i;
  for (i = 0; i < 2; i++)
    for (cur = i ? grub_term_input_autoload : grub_term_output_autoload;
	 cur; cur = next)
      {
	next = cur->next;
	grub_free (cur->name);
	grub_free (cur->modname);
	grub_free (cur);
      }
  grub_term_input_autoload = NULL;
  grub_term_output_autoload = NULL;
}


/* Read the file terminal.lst for auto-loading.  */
void
read_terminal_list (void)
{
  const char *prefix;
  char *filename;
  grub_file_t file;
  char *buf = NULL;

  prefix = grub_env_get ("prefix");
  if (!prefix)
    {
      grub_errno = GRUB_ERR_NONE;
      return;
    }
  
  filename = grub_xasprintf ("%s/terminal.lst", prefix);
  if (!filename)
    {
      grub_errno = GRUB_ERR_NONE;
      return;
    }

  file = grub_file_open (filename);
  if (!file)
    {
      grub_errno = GRUB_ERR_NONE;
      return;
    }

  /* Override previous terminal.lst.  */
  grub_terminal_autoload_free ();

  for (;; grub_free (buf))
    {
      char *p, *name;
      struct grub_term_autoload *cur;
      struct grub_term_autoload **target = NULL;
      
      buf = grub_file_getline (file);
	
      if (! buf)
	break;

      switch (buf[0])
	{
	case 'i':
	  target = &grub_term_input_autoload;
	  break;

	case 'o':
	  target = &grub_term_output_autoload;
	  break;
	}
      if (!target)
	continue;
      
      name = buf + 1;
            
      p = grub_strchr (name, ':');
      if (! p)
	continue;
      
      *p = '\0';
      while (*++p == ' ')
	;

      cur = grub_malloc (sizeof (*cur));
      if (!cur)
	{
	  grub_errno = GRUB_ERR_NONE;
	  continue;
	}
      
      cur->name = grub_strdup (name);
      if (! name)
	{
	  grub_errno = GRUB_ERR_NONE;
	  grub_free (cur);
	  continue;
	}
	
      cur->modname = grub_strdup (p);
      if (! cur->modname)
	{
	  grub_errno = GRUB_ERR_NONE;
	  grub_free (cur);
	  grub_free (cur->name);
	  continue;
	}
      cur->next = *target;
      *target = cur;
    }
  
  grub_file_close (file);

  grub_errno = GRUB_ERR_NONE;
}