/*
 * Copyright 2007-2013, Axel Dörfler, axeld@pinc-software.de.
 * Copyright 2009, Michael Lotz, mmlr@mlotz.ch. All rights reserved.
 *
 * Distributed under the terms of the MIT License.
 */


#include "utility.h"

#include <string.h>

#ifndef _BOOT_MODE
#	include <utf8_functions.h>
#endif

#include "gpt_known_guids.h"


const guid_t kEmptyGUID = {0, 0, 0, {0, 0, 0, 0, 0, 0, 0, 0}};


static void
put_utf8_byte(char*& to, size_t& left, char c)
{
	if (left <= 1)
		return;

	*(to++) = c;
	left--;
}


// #pragma mark -


void
to_utf8(const uint16* from, size_t maxFromLength, char* to, size_t toSize)
{
	for (uint32 i = 0; i < maxFromLength; i++) {
		uint16 c = B_LENDIAN_TO_HOST_INT16(from[i]);
		if (!c)
			break;

		if (c < 0x80)
			put_utf8_byte(to, toSize, c);
		else if (c < 0x800) {
			put_utf8_byte(to, toSize, 0xc0 | (c >> 6));
			put_utf8_byte(to, toSize, 0x80 | (c & 0x3f));
		} else if (c < 0x10000) {
			put_utf8_byte(to, toSize, 0xe0 | (c >> 12));
			put_utf8_byte(to, toSize, 0x80 | ((c >> 6) & 0x3f));
			put_utf8_byte(to, toSize, 0x80 | (c & 0x3f));
		} else if (c <= 0x10ffff) {
			put_utf8_byte(to, toSize, 0xf0 | (c >> 18));
			put_utf8_byte(to, toSize, 0x80 | ((c >> 12) & 0x3f));
			put_utf8_byte(to, toSize, 0x80 | ((c >> 6) & 0x3f));
			put_utf8_byte(to, toSize, 0x80 | (c & 0x3f));
		}
	}

	if (toSize > 0)
		*to = '\0';
}


#ifndef _BOOT_MODE
void
to_ucs2(const char* from, size_t fromLength, uint16* to, size_t maxToLength)
{
	size_t index = 0;
	while (from[0] != '\0' && index < maxToLength) {
		// TODO: handle characters that are not representable in UCS-2 better
		uint32 code = UTF8ToCharCode(&from);
		if (code < 0x10000)
			to[index++] = code;
	}

	if (index < maxToLength)
		to[index] = '\0';
}
#endif // !_BOOT_MODE


const char*
get_partition_type(const guid_t& guid)
{
	for (uint32 i = 0; i < sizeof(kTypeMap) / sizeof(kTypeMap[0]); i++) {
		if (kTypeMap[i].guid == guid)
			return kTypeMap[i].type;
	}

	return NULL;
}


#ifndef _BOOT_MODE
bool
get_guid_for_partition_type(const char* type, guid_t& guid)
{
	for (uint32 i = 0; i < sizeof(kTypeMap) / sizeof(kTypeMap[0]); i++) {
		if (strcmp(kTypeMap[i].type, type) == 0) {
			guid = kTypeMap[i].guid;
			return true;
		}
	}

	return false;
}
#endif // !_BOOT_MODE