/*
 * libid3tag - ID3 tag manipulation library
 * Copyright (C) 2000-2004 Underbit Technologies, Inc.
 *
 * This program 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 of the License, or
 * (at your option) any later version.
 *
 * This program 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 * $Id: render.c,v 1.11 2004/01/23 09:41:32 rob Exp $
 */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include "global.h"

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

#ifdef HAVE_ASSERT_H
# include <assert.h>
#endif

#include "id3tag.h"
#include "render.h"
#include "ucs4.h"
#include "latin1.h"
#include "utf16.h"
#include "utf8.h"

id3_length_t
id3_render_immediate(id3_byte_t ** ptr,
		     char const *value, unsigned int bytes)
{
	assert(value);
	assert(bytes == 8 || bytes == 4 || bytes == 3);

	if (ptr) {
		switch (bytes) {
		case 8:
			*(*ptr)++ = *value++;
			*(*ptr)++ = *value++;
			*(*ptr)++ = *value++;
			*(*ptr)++ = *value++;
		case 4:
			*(*ptr)++ = *value++;
		case 3:
			*(*ptr)++ = *value++;
			*(*ptr)++ = *value++;
			*(*ptr)++ = *value++;
		}
	}

	return bytes;
}

id3_length_t
id3_render_syncsafe(id3_byte_t ** ptr,
		    unsigned long num, unsigned int bytes)
{
	assert(bytes == 4 || bytes == 5);

	if (ptr) {
		switch (bytes) {
		case 5:
			*(*ptr)++ = (num >> 28) & 0x0f;
		case 4:
			*(*ptr)++ = (num >> 21) & 0x7f;
			*(*ptr)++ = (num >> 14) & 0x7f;
			*(*ptr)++ = (num >> 7) & 0x7f;
			*(*ptr)++ = (num >> 0) & 0x7f;
		}
	}

	return bytes;
}

id3_length_t
id3_render_int(id3_byte_t ** ptr, signed long num, unsigned int bytes)
{
	assert(bytes >= 1 && bytes <= 4);

	if (ptr) {
		switch (bytes) {
		case 4:
			*(*ptr)++ = num >> 24;
		case 3:
			*(*ptr)++ = num >> 16;
		case 2:
			*(*ptr)++ = num >> 8;
		case 1:
			*(*ptr)++ = num >> 0;
		}
	}

	return bytes;
}

id3_length_t
id3_render_binary(id3_byte_t ** ptr,
		  id3_byte_t const *data, id3_length_t length)
{
	if (data == 0)
		return 0;

	if (ptr) {
		memcpy(*ptr, data, length);
		*ptr += length;
	}

	return length;
}

id3_length_t
id3_render_latin1(id3_byte_t ** ptr,
		  id3_latin1_t const *latin1, int terminate)
{
	id3_length_t size;

	if (latin1 == 0)
		latin1 = (id3_latin1_t*) "";

	size = id3_latin1_size(latin1);
	if (!terminate)
		--size;

	if (ptr) {
		memcpy(*ptr, latin1, size);
		*ptr += size;
	}

	return size;
}

id3_length_t
id3_render_string(id3_byte_t ** ptr, id3_ucs4_t const *ucs4,
		  enum id3_field_textencoding encoding, int terminate)
{
	enum id3_utf16_byteorder byteorder = ID3_UTF16_BYTEORDER_ANY;

	if (ucs4 == 0)
		ucs4 = id3_ucs4_empty;

	switch (encoding) {
	case ID3_FIELD_TEXTENCODING_ISO_8859_1:
		return id3_latin1_serialize(ptr, ucs4, terminate);

	case ID3_FIELD_TEXTENCODING_UTF_16BE:
		byteorder = ID3_UTF16_BYTEORDER_BE;
	case ID3_FIELD_TEXTENCODING_UTF_16:
		return id3_utf16_serialize(ptr, ucs4, byteorder,
					   terminate);

	case ID3_FIELD_TEXTENCODING_UTF_8:
		return id3_utf8_serialize(ptr, ucs4, terminate);
	}

	return 0;
}

id3_length_t
id3_render_padding(id3_byte_t ** ptr, id3_byte_t value,
		   id3_length_t length)
{
	if (ptr) {
		memset(*ptr, value, length);
		*ptr += length;
	}

	return length;
}

/*
 * NAME:        render->paddedstring()
 * DESCRIPTION: render a space-padded string using latin1 encoding
 */
id3_length_t
id3_render_paddedstring(id3_byte_t ** ptr, id3_ucs4_t const *ucs4,
			id3_length_t length)
{
	id3_ucs4_t padded[31],
	 *data,
	 *end;

	/*
	 * latin1 encoding only (this is used for ID3v1 fields) 
	 */

	assert(length <= 30);

	data = padded;
	end = data + length;

	if (ucs4) {
		while (*ucs4 && end - data > 0) {
			*data++ = *ucs4++;

			if (data[-1] == '\n')
				data[-1] = ' ';
		}
	}

	while (end - data > 0)
		*data++ = ' ';

	*data = 0;

	return id3_latin1_serialize(ptr, padded, 0);
}