/* $Id: drv_SimpleLCD.c,v 1.3 2005/04/20 05:49:21 reinelt Exp $
 * 
 * driver for a simple serial terminal.
 * 
 * Copyright (C) 2005 Julien Aube <ob@obconseil.net>
 * Copyright (C) 2005 The LCD4Linux Team <lcd4linux-devel@users.sourceforge.net>
 *
 * This file is part of LCD4Linux.
 *
 * LCD4Linux 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.
 *
 * LCD4Linux 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * $Log: drv_SimpleLCD.c,v $
 * Revision 1.3  2005/04/20 05:49:21  reinelt
 * Changed the code to add some VT100-compatible control sequences (see the comments above).
 * A configfile boolean option 'VT100_Support' (default to 1) indicate if the display in
 * used support these control-sequences or not.
 *
 * Revision 1.2  2005/04/02 05:28:58  reinelt
 * fixed gcc4 warnings about signed/unsigned mismatches
 *
 * Revision 1.1  2005/02/24 07:06:48  reinelt
 * SimpleLCD driver added
 *
 */

/*
 * This driver simply send out caracters on the serial port, without any 
 * formatting instructions for a particular LCD device. 
 * This is useful for custom boards of for very simple LCD.
 *
 * I use it for tests on a custom-made board based on a AVR microcontroler
 * and also for driver a Point-of-Sale text-only display.
 * I assume the following :
 * - CR (0x0d) Return to the begining of the line without erasing,
 * - LF (0x0a) Initiate a new line (but without sending the cursor to 
 * the begining of the line)
 * - BS (0x08) Move the cursor to the previous caracter (but does no erase it).
 * - It's not possible to return to the first line. Thus a back buffer is used
 * in this driver.
 * 
 * ******** UPDATE *********
 * I have added a "VT-100 Compatible mode" that allows the driver to support
 * control-sequence code. This greatly reduce flickering and eliminate the need
 * for the back-buffer. But it is optional since all displays cannot support them.
 * Here are the codes:
 * Delete the display (but does not move the cursor) : 
 *    "ESC [ 2 J"     (0x1b 0x5b 0x32 0x4a)
 * Position the cursor :
 *    "ESC [ YY ; XX H" ( 0x1b 0x5b YY 0x3b XX 0x48 ) where YY is the ascii for the line 
 *    number, and XX is the ascii for the column number ( first line/column is '1', not zero)
 * Delete to the end of line from current cursor position :
 *    "ESC [ 0 K" ( 0x1b 0x5b 0x30 0x4b )
 * Set Country Code : 
 *    "ESC R NN"  (0x1b 0x52 NN) where NN is the country code *in byte, NOT ascii*.
 *    The default is 0 (USA), see below for specific countries. 
 *    the list of accessible characters page are available on this page : 
 *    http://www.wincor-nixdorf.com/internet/com/Services/Support/TechnicalSupport/POSSystems
 *    /Manuals/BAxx/index.html
 * Get the display identification : (Doesn't work reliably, timing issues here)
 *    "ESC [ 0 c" ( 0x1b 0x5b 0x30 0x63). Return a string which look like this : 
 *  ESC [ ? M ; NN ; OO ; PP ; QQ c) where M is type of display (2 for VFD),
 *  NN is the rom version, 00 is the current caracter set, PP is the number of lines and 
 *  QQ the number of colomns.  
 * 
 *
 * A "bar" capability is now provided if the config file has a "BarCharValue" parameter in it.
 *
 * The code come mostly taken from the LCDTerm driver in LCD4Linux, from 
 * Michaels Reinelt, many thanks to him.
 *
 * This driver is released under the GPL.
 */

/* 
 *
 * exported fuctions:
 *
 * struct DRIVER drv_SimpleLCD
 *
 */

#include "config.h"

#include <stdlib.h>
#include <unistd.h>
#include <string.h>

#include "debug.h"
#include "cfg.h"
#include "qprintf.h"
#include "plugin.h"
#include "widget.h"
#include "widget_text.h"
#include "widget_icon.h"
#include "widget_bar.h"
#include "drv.h"
#include "drv_generic_text.h"
#include "drv_generic_serial.h"


static char Name[]="SimpleLCD";
static char *backbuffer=0;
static int   backbuffer_size=0;
static int   vt100_mode=0;
static unsigned char  bar_char=0;

/****************************************/
/***  hardware dependant functions    ***/
/****************************************/

/** No clear function on SimpleLCD : Just send CR-LF * number of lines **/
void drv_SL_simple_clear (void)
{
  char cmd[2];
  int i;
  cmd[0] = '\r' ; cmd[1] = '\n';
  for (i=0;i<DROWS;++i) {
       drv_generic_serial_write (cmd, 2);
  }
  memset(backbuffer,' ',backbuffer_size);
}

/** vt-100 mode : send the ESC-code **/
void drv_SL_vt100_clear (void)
{
  char cmd[4];
  cmd[0] = 0x1b; cmd[1] = '[' ; cmd[2] = '2' ; cmd[3] = 'J';
  drv_generic_serial_write (cmd, 4); 
}

void drv_SL_clear (void)
{
  vt100_mode==1?drv_SL_vt100_clear():drv_SL_simple_clear();
}


/* If full_commit = true, then the whole buffer is to be sent to screen.
   if full_commit = false, then only the last line is to be sent (faster on slow screens)
*/
static void drv_SL_commit(int full_commit)
{
  int row;
  char cmd[2] = { '\r', '\n' };
  if (full_commit) {
    for (row=0;row < DROWS; row++) {
       drv_generic_serial_write (cmd, 2);
       drv_generic_serial_write(backbuffer+(DCOLS*row),DCOLS);
    }
  } else {
    drv_generic_serial_write (cmd, 1); /* Go to the beginning of the line only */
    drv_generic_serial_write(backbuffer+(DCOLS*(DROWS-1)),DCOLS);
  }
}

static void drv_SL_simple_write (const int row, const int col, const char *data, int len)
{
   memcpy(backbuffer+(row*DCOLS)+col,data,len);
   if (row == DROWS-1)
      drv_SL_commit(0);
   else
      drv_SL_commit(1);
}

static void drv_SL_vt100_write (const int row, const int col, const char *data, int len)
{
  char cmd[8];
    cmd[0] = 0x1b;                 cmd[1] = '['; 
    cmd[2] = row + '1';  cmd[3] = ';';
    cmd[4] = (col/10) + '0' ;      cmd[5] = (col%10) + '1' ; 
    cmd[6] = 'H';
    drv_generic_serial_write (cmd, 7);
    drv_generic_serial_write (data,len); 
}


static int drv_SL_start (const char *section, const int quiet)
{
  int rows=-1, cols=-1;
  unsigned int flags=0;
  char *s;
  char * model=0;
  
  vt100_mode = 0;
  model = cfg_get(section,"Model","generic");
  if (model != NULL && *model != '\0')
  {
  	if ( strcasecmp("vt100",model) == 0 ) 
          vt100_mode = 1;
  }
  
  cfg_number(section,"BarCharValue",0,0,255,&flags);
  bar_char = flags;  
  cfg_number(section,"Options",0,0,0xffff,&flags);
  if (drv_generic_serial_open(section, Name, flags) < 0) return -1;
  
  s=cfg_get(section, "Size", NULL);
  if (s==NULL || *s=='\0') {
     error ("%s: no '%s.Size' entry from %s", Name, section, cfg_source());
     return -1;
  }
  if (sscanf(s,"%dx%d",&cols,&rows)!=2 || rows<1 || cols<1) {
    error ("%s: bad %s.Size '%s' from %s", Name, section, s, cfg_source());
    free (s);
    return -1;
  }
  
  DROWS = rows;
  DCOLS = cols;
  
  if ( ! vt100_mode) { 
     backbuffer_size = DROWS * DCOLS;
     backbuffer = malloc(backbuffer_size);
     if ( ! backbuffer ){  
        return -1;
     }
  }
  
  /* real worker functions */
  if ( vt100_mode ) {
       drv_generic_text_real_write = drv_SL_vt100_write;
  }
  else { 
       drv_generic_text_real_write = drv_SL_simple_write;
  }
 
   drv_SL_clear();   /* clear */

  
  if (!quiet) {
    char buffer[40];
    qprintf(buffer, sizeof(buffer), "%s %dx%d", Name, DCOLS, DROWS);
    if (drv_generic_text_greet (buffer, NULL)) {
      sleep (3);
      drv_SL_clear();
    }
  }
  
  return 0;
}


/****************************************/
/***            plugins               ***/
/****************************************/

/* none */


/****************************************/
/***        widget callbacks          ***/
/****************************************/


/* using drv_generic_text_draw(W) */


/****************************************/
/***        exported functions        ***/
/****************************************/


/* list models */
int drv_SL_list (void)
{
  printf ("generic vt100");
  return 0;
}


/* initialize driver & display */
int drv_SL_init (const char *section, const int quiet)
{
  WIDGET_CLASS wc;
  int ret;  
  
  /* display preferences */
  XRES  = 5;      /* pixel width of one char  */
  YRES  = 8;      /* pixel height of one char  */
  CHARS = 0;      /* number of user-defineable characters */
  CHAR0 = 0;      /* ASCII of first user-defineable char */

  GOTO_COST = -1;  /* number of bytes a goto command requires */
  


  /* start display */
  if ((ret=drv_SL_start (section, quiet))!=0)
    return ret;
  
  /* initialize generic text driver */
  if ((ret=drv_generic_text_init(section, Name))!=0)
    return ret;

  /* register text widget */
  wc=Widget_Text;
  wc.draw=drv_generic_text_draw;
  widget_register(&wc);
  
  /* register plugins */
  /* none */

  return 0;
}


/* close driver & display */
int drv_SL_quit (const int quiet)
{

  info("%s: shutting down.", Name);
  
  drv_generic_text_quit();
  
  /* clear display */
  drv_SL_clear();
  
  /* say goodbye... */
  if (!quiet) {
    drv_generic_text_greet ("goodbye!", NULL);
  }
  
  drv_generic_serial_close();
  
  if ( backbuffer ) {
    free(backbuffer) ; backbuffer=0; backbuffer_size=0;
  }
  return (0);
}


DRIVER drv_SimpleLCD = {
  name: Name,
  list: drv_SL_list,
  init: drv_SL_init,
  quit: drv_SL_quit, 
};