/* Terminal hooks for Windows NT port of GNU Emacs.
   Copyright (C) 1992 Free Software Foundation, Inc.

   This file is part of GNU Emacs.

   GNU Emacs 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 2, or (at your option) any later
   version.

   GNU Emacs 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 GNU Emacs; see the file COPYING.  If not, write to the Free Software
   Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.

   Tim Fleehart (apollo@online.com)		1-17-92
   Geoff Voelker (voelker@cs.washington.edu)	9-12-93
*/


#include <stdlib.h>
#include <stdio.h>

#include "config.h"

#include <windows.h>

#include "lisp.h"
#include "frame.h"
#include "disptab.h"
#include "termhooks.h"

#include "ntinevt.h"

/* frrom window.c */
extern Lisp_Object Frecenter ();

/* from keyboard.c */
extern int detect_input_pending ();

/* from sysdep.c */
extern int read_input_pending ();

extern FRAME_PTR updating_frame;
extern int meta_key;

static void move_cursor (int row, int col);
static void clear_to_end (void);
static void clear_frame (void);
static void clear_end_of_line (int);
static void ins_del_lines (int vpos, int n);
static void change_line_highlight (int, int, int);
static void reassert_line_highlight (int, int);
static void insert_glyphs (GLYPH *start, int len);
static void write_glyphs (GLYPH *string, int len);
static void delete_glyphs (int n);
static void ring_bell (void);
static void reset_terminal_modes (void);
static void set_terminal_modes (void);
static void set_terminal_window (int size);
static void update_begin (FRAME_PTR f);
static void update_end (FRAME_PTR f);
static void reset_kbd (void);
static void unset_kbd (void);
static int  hl_mode (int new_highlight);

void
DebPrint ()
{
}

/* Init hook called in init_keyboard.  */
void (*keyboard_init_hook)(void) = reset_kbd;
    
COORD	cursor_coords;
HANDLE	prev_screen, cur_screen;
UCHAR	char_attr, char_attr_normal, char_attr_reverse;
HANDLE  keyboard_handle;


/* Setting this as the ctrl handler prevents emacs from being killed when
 * someone hits ^C in a 'suspended' session (child shell).  */
BOOL
ctrl_c_handler (unsigned long type)
{
  return (type == CTRL_C_EVENT) ? TRUE : FALSE;
}

/* If we're updating a frame, use it as the current frame
   Otherwise, use the selected frame.  */
#define PICK_FRAME() (updating_frame ? updating_frame : selected_frame)

/* Move the cursor to (row, col).  */
void
move_cursor (int row, int col)
{
  cursor_coords.X = col;
  cursor_coords.Y = row;
  
  if (updating_frame == NULL)
    {
      SetConsoleCursorPosition (cur_screen, cursor_coords);
    }
}

/* Clear from cursor to end of screen.  */
void
clear_to_end (void)
{
  FRAME_PTR f = PICK_FRAME ();
  
  clear_end_of_line (FRAME_WIDTH (f) - 1);
  ins_del_lines (cursor_coords.Y, FRAME_HEIGHT (f) - cursor_coords.Y - 1);
}

/* Clear the frame.  */
void
clear_frame (void)
{
  SMALL_RECT scroll;
  COORD	     dest;
  CHAR_INFO  fill;
  FRAME_PTR  f = PICK_FRAME ();
  
  hl_mode (0);
  
  scroll.Top = 0;
  scroll.Bottom = FRAME_HEIGHT (f) - 1;
  scroll.Left = 0;
  scroll.Right = FRAME_WIDTH (f) - 1;
  
  dest.Y = FRAME_HEIGHT (f);
  dest.X = 0;
  
  fill.Char.AsciiChar = 0x20;
  fill.Attributes = char_attr;
  
  ScrollConsoleScreenBuffer (cur_screen, &scroll, NULL, dest, &fill);
  move_cursor (0, 0);
}


static GLYPH glyph_base[256];
static BOOL  ceol_initialized = FALSE;

/* Clear from Cursor to end (what's "standout marker"?).  */
void
clear_end_of_line (int end)
{
  if (!ceol_initialized)
    {
      int i;
      for (i = 0; i < 256; i++)
        {
	  glyph_base[i] = SPACEGLYPH;	/* empty space	*/
        }
      ceol_initialized = TRUE;
    }
  write_glyphs (glyph_base, end - cursor_coords.X);	/* fencepost ?	*/
}

/* Insert n lines at vpos. if n is negative delete -n lines.  */
void
ins_del_lines (int vpos, int n)
{
  int	     i, nb, save_highlight;
  SMALL_RECT scroll;
  COORD	     dest;
  CHAR_INFO  fill;
  FRAME_PTR  f = PICK_FRAME ();

  if (n < 0)
    {
      scroll.Top = vpos - n;
      scroll.Bottom = FRAME_HEIGHT (f);
      dest.Y = vpos;
    }
  else
    {
      scroll.Top = vpos;
      scroll.Bottom = FRAME_HEIGHT (f) - n;
      dest.Y = vpos + n;
    }
  scroll.Left = 0;
  scroll.Right = FRAME_WIDTH (f);
  
  dest.X = 0;
  
  save_highlight = hl_mode (0);
  
  fill.Char.AsciiChar = 0x20;
  fill.Attributes = char_attr;
  
  ScrollConsoleScreenBuffer (cur_screen, &scroll, NULL, dest, &fill);

  /* Here we have to deal with a win32 console flake: If the scroll
     region looks like abc and we scroll c to a and fill with d we get
     cbd... if we scroll block c one line at a time to a, we get cdd...
     Emacs expects cdd consistently... So we have to deal with that
     here... (this also occurs scrolling the same way in the other
     direction.  */

  if (n > 0)
    {
      if (scroll.Bottom < dest.Y)
        {
	  for (i = scroll.Bottom; i < dest.Y; i++)
            {
	      move_cursor (i, 0);
	      clear_end_of_line (FRAME_WIDTH (f));
            }
        }
    }
  else
    {
      nb = dest.Y + (scroll.Bottom - scroll.Top) + 1;

      if (nb < scroll.Top)
        { 
	  for (i = nb; i < scroll.Top; i++)
            {
	      move_cursor (i, 0);
	      clear_end_of_line (FRAME_WIDTH (f));
            }
        }
    }
  
  cursor_coords.X = 0;
  cursor_coords.Y = vpos;
  
  hl_mode (save_highlight);
}

/* Changes attribute to use when drawing characters to control.  */
static int
hl_mode (int new_highlight)
{
  static int highlight = 0;
  int old_highlight;
  
  old_highlight = highlight;
  highlight = (new_highlight != 0);
  if (highlight)
    {
      char_attr = char_attr_reverse;
    }
  else
    {
      char_attr = char_attr_normal;
    }
  return old_highlight;
}

/* Call this when about to modify line at position VPOS and change whether it
   is highlighted.  */
void
change_line_highlight (int new_highlight, int vpos, int first_unused_hpos)
{
  hl_mode (new_highlight);
  move_cursor (vpos, 0);
  clear_end_of_line (first_unused_hpos);
}

/* External interface to control of standout mode. Call this when about to
 * modify line at position VPOS and not change whether it is highlighted.  */
void
reassert_line_highlight (int highlight, int vpos)
{
  hl_mode (highlight);
  vpos;				/* pedantic compiler silencer */
}

#undef	LEFT
#undef	RIGHT
#define	LEFT	1
#define	RIGHT	0

void
scroll_line (int dist, int direction)
{
  /* The idea here is to implement a horizontal scroll in one line to
     implement delete and half of insert.  */
  SMALL_RECT scroll;
  COORD	     dest;
  CHAR_INFO  fill;
  FRAME_PTR  f = PICK_FRAME ();
  
  scroll.Top = cursor_coords.Y;
  scroll.Bottom = cursor_coords.Y;
  
  if (direction == LEFT)
    {
      scroll.Left = cursor_coords.X + dist;
      scroll.Right = FRAME_WIDTH (f) - 1;
    }
  else
    {
      scroll.Left = cursor_coords.X;
      scroll.Right = FRAME_WIDTH (f) - dist - 1;
    }
  
  dest.X = cursor_coords.X;
  dest.Y = cursor_coords.Y;
  
  fill.Char.AsciiChar = 0x20;
  fill.Attributes = char_attr;
  
  ScrollConsoleScreenBuffer (cur_screen, &scroll, NULL, dest, &fill);
}


/* If start is zero insert blanks instead of a string at start ?. */
void
insert_glyphs (register GLYPH *start, register int len)
{
  scroll_line (len, RIGHT);

  /* Move len chars to the right starting at cursor_coords, fill with blanks */
  if (start)
    {
      /* Print the first len characters of start, cursor_coords.X adjusted
	 by write_glyphs.  */
	
      write_glyphs (start, len);
    }
  else
    {
      clear_end_of_line (cursor_coords.X + len);
    }
}

void
write_glyphs (register GLYPH *string, register int len)
{
  register unsigned int glyph_len = GLYPH_TABLE_LENGTH;
  Lisp_Object *glyph_table = GLYPH_TABLE_BASE;
  FRAME_PTR f = PICK_FRAME ();
  register char *ptr;
  GLYPH glyph;
  WORD *attrs;
  char *chars;
  int i;
  
  attrs = alloca (len * sizeof (*attrs));
  chars = alloca (len * sizeof (*chars));
  if (attrs == NULL || chars == NULL)
    {
      printf ("alloca failed in write_glyphs\n");
      return;
    }
  
  /* We have to deal with the glyph indirection...go over the glyph
     buffer and extract the characters.  */
  ptr = chars;
  while (--len >= 0)
    {
      glyph = *string++;

      if (glyph > glyph_len)
        {
	  *ptr++ = glyph & 0xFF;
	  continue;
	}
      GLYPH_FOLLOW_ALIASES (glyph_table, glyph_len, glyph);
      if (GLYPH_FACE (fixfix, glyph) != 0)
	printf ("Glyph face is %d\n", GLYPH_FACE (fixfix, glyph));
      if (GLYPH_SIMPLE_P (glyph_table, glyph_len, glyph))
        {
	  *ptr++ = glyph & 0xFF;
	  continue;
	}
      for (i = 0; i < GLYPH_LENGTH (glyph_table, glyph); i++)
        {
	  *ptr++ = (GLYPH_STRING (glyph_table, glyph))[i];
	}
    }
  
  /* Number of characters we have in the buffer.  */
  len = ptr-chars;
  
  /* Fill in the attributes for these characters.  */
  memset (attrs, char_attr, len*sizeof (*attrs));
  
  /* Write the attributes.  */
  if (!WriteConsoleOutputAttribute (cur_screen, attrs, len, cursor_coords, &i))
    {
      printf ("Failed writing console attributes.\n");
      fflush (stdout);
    }

  /* Write the characters.  */
  if (!WriteConsoleOutputCharacter (cur_screen, chars, len, cursor_coords, &i))
    {
      printf ("Failed writing console characters.\n");
      fflush (stdout);
    }
  
  cursor_coords.X += len;
  move_cursor (cursor_coords.Y, cursor_coords.X);
}

void
delete_glyphs (int n)
{
  /* delete chars means scroll chars from cursor_coords.X + n to 
     cursor_coords.X, anything beyond the edge of the screen should 
     come out empty...  */

  scroll_line (n, LEFT);
}

void
ring_bell (void)
{
  Beep (666, 100);
}

/* Reset to the original console mode but don't get rid of our console
   For suspending emacs.  */
void
restore_console (void)
{
  unset_kbd ();
  SetConsoleActiveScreenBuffer (prev_screen);
}

/* Put our console back up, for ending a suspended session.  */
void
take_console (void)
{
  reset_kbd ();
  SetConsoleActiveScreenBuffer (cur_screen);
}
   
void
reset_terminal_modes (void)
{
  unset_kbd ();
  SetConsoleActiveScreenBuffer (prev_screen);
  CloseHandle (cur_screen);
  cur_screen = NULL;
}

void
set_terminal_modes (void)
{
  CONSOLE_CURSOR_INFO cci;

  if (cur_screen == NULL)
    {
      reset_kbd ();
      cur_screen = CreateConsoleScreenBuffer (GENERIC_READ | GENERIC_WRITE,
                                              0, NULL,
                                              CONSOLE_TEXTMODE_BUFFER,
                                              NULL);

      if (cur_screen == INVALID_HANDLE_VALUE)
        {
	  printf ("CreateConsoleScreenBuffer failed in ResetTerm\n");
	  printf ("LastError = 0x%lx\n", GetLastError ());
	  fflush (stdout);
	  exit (0);
	}

      SetConsoleActiveScreenBuffer (cur_screen);

      /* make cursor big and visible */
      cci.dwSize = 100;
      cci.bVisible = TRUE;
      (void) SetConsoleCursorInfo (cur_screen, &cci);
    }
}

/* hmmm... perhaps these let us bracket screen changes so that we can flush
   clumps rather than one-character-at-a-time...
   
   we'll start with not moving the cursor while an update is in progress.  */
void
update_begin (FRAME_PTR f)
{
}

void
update_end (FRAME_PTR f)
{
  SetConsoleCursorPosition (cur_screen, cursor_coords);
}

void
set_terminal_window (int size)
{
}

void
unset_kbd (void)
{
  SetConsoleMode (keyboard_handle, ENABLE_PROCESSED_INPUT | ENABLE_LINE_INPUT |
		  ENABLE_ECHO_INPUT | ENABLE_MOUSE_INPUT);
}

void
reset_kbd (void)
{
  keyboard_handle = GetStdHandle (STD_INPUT_HANDLE);
  SetConsoleMode (keyboard_handle, ENABLE_MOUSE_INPUT | ENABLE_WINDOW_INPUT);
}

typedef int (*term_hook) ();

void
initialize_win_nt_display (void)
{
  CONSOLE_SCREEN_BUFFER_INFO	info;
  
  cursor_to_hook		= (term_hook) move_cursor;
  raw_cursor_to_hook		= (term_hook) move_cursor;
  clear_to_end_hook		= (term_hook) clear_to_end;
  clear_frame_hook		= (term_hook) clear_frame;
  clear_end_of_line_hook	= (term_hook) clear_end_of_line;
  ins_del_lines_hook		= (term_hook) ins_del_lines;
  change_line_highlight_hook	= (term_hook) change_line_highlight;
  reassert_line_highlight_hook  = (term_hook) reassert_line_highlight;
  insert_glyphs_hook		= (term_hook) insert_glyphs;
  write_glyphs_hook		= (term_hook) write_glyphs;
  delete_glyphs_hook		= (term_hook) delete_glyphs;
  ring_bell_hook		= (term_hook) ring_bell;
  reset_terminal_modes_hook	= (term_hook) reset_terminal_modes;
  set_terminal_modes_hook	= (term_hook) set_terminal_modes;
  set_terminal_window_hook	= (term_hook) set_terminal_window;
  update_begin_hook		= (term_hook) update_begin;
  update_end_hook		= (term_hook) update_end;
  
  read_socket_hook = win32_read_socket;
  mouse_position_hook = win32_mouse_position;
  
  prev_screen = GetStdHandle (STD_OUTPUT_HANDLE);
  
  set_terminal_modes ();
  
  GetConsoleScreenBufferInfo (cur_screen, &info);
  
  meta_key = 1;
  char_attr = info.wAttributes & 0xFF;
  char_attr_normal = char_attr;
  char_attr_reverse = ((char_attr & 0xf) << 4) + ((char_attr & 0xf0) >> 4);
  
  FRAME_HEIGHT (selected_frame) = info.dwSize.Y;	/* lines per page */
  FRAME_WIDTH (selected_frame) = info.dwSize.X;  /* characters per line */
  
  move_cursor (0, 0);
  
  clear_frame ();
}

DEFUN ("set-screen-color", Fset_screen_color, Sset_screen_color, 2, 2, 0,
       "Set screen colors.")
    (foreground, background)
    Lisp_Object foreground;
    Lisp_Object background;
{
  char_attr_normal = XFASTINT (foreground) + (XFASTINT (background) << 4);
  char_attr_reverse = XFASTINT (background) + (XFASTINT (foreground) << 4);

  Frecenter (Qnil);
  return Qt;
}

DEFUN ("set-cursor-size", Fset_cursor_size, Sset_cursor_size, 1, 1, 0,
       "Set cursor size.")
    (size)
    Lisp_Object size;
{
  CONSOLE_CURSOR_INFO cci;
  cci.dwSize = XFASTINT (size);
  cci.bVisible = TRUE;
  (void) SetConsoleCursorInfo (cur_screen, &cci);
  
  return Qt;
}

void
pixel_to_glyph_coords (FRAME_PTR f, int pix_x, int pix_y, int *x, int *y,
		      void *bounds, int noclip)
{
  *x = pix_x;
  *y = pix_y;
}

void
glyph_to_pixel_coords (FRAME_PTR f, int x, int y, int *pix_x, int *pix_y)
{
  *pix_x = x;
  *pix_y = y;
}

_VOID_
syms_of_ntterm ()
{
  defsubr (&Sset_screen_color);
  defsubr (&Sset_cursor_size);
}