/* Copyright (C) 1989, 1992, 1995 Aladdin Enterprises.  All rights reserved.
  
  This file is part of Aladdin Ghostscript.
  
  Aladdin Ghostscript is distributed with NO WARRANTY OF ANY KIND.  No author
  or distributor accepts any responsibility for the consequences of using it,
  or for whether it serves any particular purpose or works at all, unless he
  or she says so in writing.  Refer to the Aladdin Ghostscript Free Public
  License (the "License") for full details.
  
  Every copy of Aladdin Ghostscript must include a copy of the License,
  normally in a plain ASCII text file named PUBLIC.  The License grants you
  the right to copy, modify and redistribute Aladdin Ghostscript, but only
  under certain conditions described in the License.  Among other things, the
  License requires that the copyright notice and this notice be preserved on
  all copies.
*/

/* gdevokii.c */
/*
 * Okidata IBM compatible dot-matrix printer driver for Ghostscript.
 *
 * This device is for the Okidata Microline IBM compatible 9 pin dot
 * matrix printers.  It is derived from the Epson 9 pin printer driver
 * using the standard 1/72" vertical pin spacing and the 60/120/240
 * dpi horizontal resolutions.  The vertical feed resolution however
 * is 1/144" and the Okidata implements the standard 1/216" requests
 * through "scaling":
 *
 *   (power on)
 *   "\033J\001" (vertical feed 1/216")  => Nothing happens
 *   "\033J\001" (vertical feed 1/216")  => Advance 1/144"
 *   "\033J\001" (vertical feed 1/216")  => Advance 1/144"
 *   "\033J\001" (vertical feed 1/216")  => Nothing happens
 *   (and so on)
 *
 * The simple minded accounting used here keep track of when the
 * page actually advances assumes the printer starts in a "power on"
 * state.
 * 
 * Supported resolutions are:
 *
 *    60x72      60x144
 *   120x72     120x144
 *   240x72     240x144
 *
 */
#include "gdevprn.h"

/*
 * Valid values for X_DPI:
 *
 *     60, 120, 240
 *
 * The value specified at compile time is the default value used if the
 * user does not specify a resolution at runtime.
 */

#ifndef X_DPI
#  define X_DPI 120
#endif

/*
 * Valid values for Y_DPI:
 *
 *     72, 144
 *
 * The value specified at compile time is the default value used if the
 * user does not specify a resolution at runtime.
 */

#ifndef Y_DPI
#  define Y_DPI 72
#endif

/* The device descriptor */
private dev_proc_print_page(okiibm_print_page);

/* Okidata IBM device */
gx_device_printer far_data gs_okiibm_device =
  prn_device(prn_std_procs, "okiibm",
	DEFAULT_WIDTH_10THS, DEFAULT_HEIGHT_10THS,
	X_DPI, Y_DPI,
	0.25, 0.0, 0.25, 0.0,			/* margins */
	1, okiibm_print_page);

/* ------ Internal routines ------ */

/* Forward references */
private void okiibm_output_run(P6(byte *, int, int, char, FILE *, int));

/* Send the page to the printer. */
private int
okiibm_print_page1(gx_device_printer *pdev, FILE *prn_stream, int y_9pin_high,
  const char *init_string, int init_length,
  const char *end_string, int end_length)
{	
	static const char graphics_modes_9[5] =
	{	
	-1, 0 /*60*/, 1 /*120*/, -1, 3 /*240*/
	};

	int in_y_mult = (y_9pin_high ? 2 : 1);
	int line_size = gdev_mem_bytes_per_scan_line((gx_device *)pdev);
	/* Note that in_size is a multiple of 8. */
	int in_size = line_size * (8 * in_y_mult);
	byte *buf1 = (byte *)gs_malloc(in_size, 1, "okiibm_print_page(buf1)");
	byte *buf2 = (byte *)gs_malloc(in_size, 1, "okiibm_print_page(buf2)");
	byte *in = buf1;
	byte *out = buf2;
	int out_y_mult = 1;
	int x_dpi = pdev->x_pixels_per_inch;
	char start_graphics = graphics_modes_9[x_dpi / 60];
	int first_pass = (start_graphics == 3 ? 1 : 0);
	int last_pass = first_pass * 2;
	int y_passes = (y_9pin_high ? 2 : 1);
	int skip = 0, lnum = 0, pass, ypass;
	int y_step = 0;

	/* Check allocations */
	if ( buf1 == 0 || buf2 == 0 )
	{	if ( buf1 ) 
		  gs_free((char *)buf1, in_size, 1, "okiibm_print_page(buf1)");
		if ( buf2 ) 
		  gs_free((char *)buf2, in_size, 1, "okiibm_print_page(buf2)");
		return_error(gs_error_VMerror);
	}

	/* Initialize the printer. */
	fwrite(init_string, 1, init_length, prn_stream);

	/* Print lines of graphics */
	while ( lnum < pdev->height )
	{	
		byte *in_data;
		byte *inp;
		byte *in_end;
		byte *out_end;
		int lcnt;

		/* Copy 1 scan line and test for all zero. */
		gdev_prn_get_bits(pdev, lnum, in, &in_data);
		if ( in_data[0] == 0 &&
		     !memcmp((char *)in_data, (char *)in_data + 1, line_size - 1)
		   )
	    	{	
			lnum++;
			skip += 2 / in_y_mult;
			continue;
		}

		/*
		 * Vertical tab to the appropriate position.
		 * The skip count is in 1/144" steps.  If total
		 * vertical request is not a multiple od 1/72"
		 * we need to make sure the page is actually
		 * going to advance.
		 */
		if ( skip & 1 )
		{
			int n = 1 + (y_step == 0 ? 1 : 0);
			fprintf(prn_stream, "\033J%c", n);
			y_step = (y_step + n) % 3;
			skip -= 1;
		}
		skip = skip / 2 * 3;
		while ( skip > 255 )
		{	
			fputs("\033J\377", prn_stream);
			skip -= 255;
		}
		if ( skip )
		{
			fprintf(prn_stream, "\033J%c", skip);
		}

		/* Copy the the scan lines. */
	    	lcnt = gdev_prn_copy_scan_lines(pdev, lnum, in, in_size);
		if ( lcnt < 8 * in_y_mult )
		{	/* Pad with lines of zeros. */
			memset(in + lcnt * line_size, 0,
			       in_size - lcnt * line_size);
		}

		if ( y_9pin_high )
		{	/* Shuffle the scan lines */
			byte *p;
			int i;
			static const char index[] =
			{  0, 2, 4, 6, 8, 10, 12, 14,
			   1, 3, 5, 7, 9, 11, 13, 15
			};
			for ( i = 0; i < 16; i++ )
			{
				memcpy( out + (i * line_size),
				        in + (index[i] * line_size),
				        line_size);
			}
			p = in;
			in = out;
			out = p;
		}

	for ( ypass = 0; ypass < y_passes; ypass++ )
	{
	    for ( pass = first_pass; pass <= last_pass; pass++ )
	    {
		/* We have to 'transpose' blocks of 8 pixels x 8 lines, */
		/* because that's how the printer wants the data. */

	        if ( pass == first_pass )
	        {
		    out_end = out;
		    inp = in;
		    in_end = inp + line_size;
    
    	            for ( ; inp < in_end; inp++, out_end += 8 )
    	            { 
    		        gdev_prn_transpose_8x8(inp + (ypass * 8 * line_size), 
					       line_size, out_end, 1);
		    }
		    /* Remove trailing 0s. */
		    while ( out_end > out && out_end[-1] == 0 )
	            {
		       	out_end--;
		    }
		}

		/* Transfer whatever is left and print. */
		if ( out_end > out )
	        {
		    okiibm_output_run(out, (int)(out_end - out),
			           out_y_mult, start_graphics,
				   prn_stream, pass);
	        }
	    	fputc('\r', prn_stream);
	    }
	    if ( ypass < y_passes - 1 )
	    {
		int n = 1 + (y_step == 0 ? 1 : 0);
		fprintf(prn_stream, "\033J%c", n);
		y_step = (y_step + n) % 3;
	    }
	}
	skip = 16 - y_passes + 1;		/* no skip on last Y pass */
	lnum += 8 * in_y_mult;
	}

	/* Reinitialize the printer. */
	fwrite(end_string, 1, end_length, prn_stream);
	fflush(prn_stream);

	gs_free((char *)buf2, in_size, 1, "okiibm_print_page(buf2)");
	gs_free((char *)buf1, in_size, 1, "okiibm_print_page(buf1)");
	return 0;
}

/* Output a single graphics command. */
/* pass=0 for all columns, 1 for even columns, 2 for odd columns. */
private void
okiibm_output_run(byte *data, int count, int y_mult,
  char start_graphics, FILE *prn_stream, int pass)
{	
	int xcount = count / y_mult;

	fputc(033, prn_stream);
	fputc("KLYZ"[start_graphics], prn_stream);
	fputc(xcount & 0xff, prn_stream);
	fputc(xcount >> 8, prn_stream);
	if ( !pass )
	{
		fwrite(data, 1, count, prn_stream);
	}
	else
	{	
		/* Only write every other column of y_mult bytes. */
		int which = pass;
		register byte *dp = data;
		register int i, j;

		for ( i = 0; i < xcount; i++, which++ )
		{
			for ( j = 0; j < y_mult; j++, dp++ )
			{
				putc(((which & 1) ? *dp : 0), prn_stream);
			}
		}
	}
}

/* The print_page procedures are here, to avoid a forward reference. */

private const char okiibm_init_string[]	= { 0x18 };
private const char okiibm_end_string[]	= { 0x0c };
private const char okiibm_one_direct[]	= { 0x1b, 0x55, 0x01 };
private const char okiibm_two_direct[]	= { 0x1b, 0x55, 0x00 };

private int
okiibm_print_page(gx_device_printer *pdev, FILE *prn_stream)
{
	char init_string[16], end_string[16];
	int init_length, end_length;

	init_length = sizeof(okiibm_init_string);
	memcpy(init_string, okiibm_init_string, init_length);

	end_length = sizeof(okiibm_end_string);
	memcpy(end_string, okiibm_end_string, end_length);

	if ( pdev->y_pixels_per_inch > 72 &&
	     pdev->x_pixels_per_inch > 60 )
	{
		/* Unidirectional printing for the higher resolutions. */
		memcpy( init_string + init_length, okiibm_one_direct,
		        sizeof(okiibm_one_direct) );
		init_length += sizeof(okiibm_one_direct);

		memcpy( end_string + end_length, okiibm_two_direct,
		        sizeof(okiibm_two_direct) );
		end_length += sizeof(okiibm_two_direct);
	}
	
	return okiibm_print_page1( pdev, prn_stream, 
				   pdev->y_pixels_per_inch > 72 ? 1 : 0,
				   init_string, init_length,
				   end_string, end_length );
}
