/* $Id$ */

#include "stdafx.h"

#include "openttd.h"

#include "functions.h"

#include "string.h"

#include "macros.h"

#include "table/control_codes.h"

#include <stdarg.h>

#include <ctype.h> // required for tolower()

void ttd_strlcat(char *dst, const char *src, size_t size)

{

	assert(size > 0);

	for (; size > 0 && *dst != '\0'; --size, ++dst) {}

	assert(size > 0);

	while (--size > 0 && *src != '\0') *dst++ = *src++;

	*dst = '\0';

}

void ttd_strlcpy(char *dst, const char *src, size_t size)

{

	assert(size > 0);

	while (--size > 0 && *src != '\0') *dst++ = *src++;

	*dst = '\0';

}

char* strecat(char* dst, const char* src, const char* last)

{

	assert(dst <= last);

	for (; *dst != '\0'; ++dst)

		if (dst == last) return dst;

	for (; *src != '\0' && dst != last; ++dst, ++src) *dst = *src;

	*dst = '\0';

	return strecpy(dst, src, last);

}

char* strecpy(char* dst, const char* src, const char* last)

{

	assert(dst <= last);

	for (; *src != '\0' && dst != last; ++dst, ++src) *dst = *src;

	*dst = '\0';

#if 1

	if (dst == last && *src != '\0') {

		error("String too long for destination buffer");

	}

#endif

	return dst;

}

char* CDECL str_fmt(const char* str, ...)

{

	char buf[4096];

	va_list va;

	int len;

	char* p;

	va_start(va, str);

	len = vsnprintf(buf, lengthof(buf), str, va);

	va_end(va);

	p = malloc(len + 1);

	if (p != NULL) memcpy(p, buf, len + 1);

	return p;

}

void str_validate(char *str)

{

	char *dst = str;

	WChar c;

	size_t len;

	for (len = Utf8Decode(&c, str); c != '\0'; len = Utf8Decode(&c, str)) {

		if (IsPrintable(c) && (c < SCC_SPRITE_START || c > SCC_SPRITE_END ||

			IsValidChar(c - SCC_SPRITE_START, CS_ALPHANUMERAL))) {

			/* Copy the character back. Even if dst is current the same as str

			 * (i.e. no characters have been changed) this is quicker than

			 * moving the pointers ahead by len */

			do {

				*dst++ = *str++;

			} while (--len != 0);

		} else {

			/* Replace the undesirable character with a question mark */

			str += len;

			*dst++ = '?';

		}

	}

	*dst = '\0';

}

void str_strip_colours(char *str)

{

	char *dst = str;

	WChar c;

	size_t len;

	for (len = Utf8Decode(&c, str); c != '\0'; len = Utf8Decode(&c, str)) {

		if (c < SCC_BLUE || c > SCC_BLACK) {

			/* Copy the character back. Even if dst is current the same as str

			 * (i.e. no characters have been changed) this is quicker than

			 * moving the pointers ahead by len */

			do {

				*dst++ = *str++;

			} while (--len != 0);

		} else {

			/* Just skip (strip) the colour codes */

			str += len;

		}

	}

	*dst = '\0';

}

/** Convert a given ASCII string to lowercase.

 * NOTE: only support ASCII characters, no UTF8 fancy. As currently

 * the function is only used to lowercase data-filenames if they are

 * not found, this is sufficient. If more, or general functionality is

 * needed, look to r7271 where it was removed because it was broken when

 * using certain locales: eg in Turkish the uppercase 'I' was converted to

 * '?', so just revert to the old functionality */

void strtolower(char *str)

{

	for (; *str != '\0'; str++) *str = tolower(*str);

}

/**

 * Only allow certain keys. You can define the filter to be used. This makes

 *  sure no invalid keys can get into an editbox, like BELL.

 * @param key character to be checked

 * @param afilter the filter to use

 * @return true or false depending if the character is printable/valid or not

 */

bool IsValidChar(WChar key, CharSetFilter afilter)

{

	switch (afilter) {

		case CS_ALPHANUMERAL: return IsPrintable(key);

		case CS_NUMERAL:      return (key >= '0' && key <= '9');

		case CS_ALPHA:        return IsPrintable(key) && !(key >= '0' && key <= '9');

	}

	return false;

}

#ifdef WIN32

int CDECL snprintf(char *str, size_t size, const char *format, ...)

{

	va_list ap;

	int ret;

	va_start(ap, format);

	ret = vsnprintf(str, size, format, ap);

	va_end(ap);

	return ret;

}

#ifdef _MSC_VER

int CDECL vsnprintf(char *str, size_t size, const char *format, va_list ap)

{

	int ret;

	ret = _vsnprintf(str, size, format, ap);

	if (ret < 0) str[size - 1] = '\0';

	return ret;

}

#endif /* _MSC_VER */

#endif /* WIN32 */

/* UTF-8 handling routines */

/* Decode and consume the next UTF-8 encoded character

 * @param c Buffer to place decoded character.

 * @param s Character stream to retrieve character from.

 * @return Number of characters in the sequence.

 */

size_t Utf8Decode(WChar *c, const char *s)

{

	assert(c != NULL);

	if (!HASBIT(s[0], 7)) {

		/* Single byte character: 0xxxxxxx */

		*c = s[0];

		return 1;

	} else if (GB(s[0], 5, 3) == 6) {

		if (IsUtf8Part(s[1])) {

			/* Double byte character: 110xxxxx 10xxxxxx */

			*c = GB(s[0], 0, 5) << 6 | GB(s[1], 0, 6);

			if (*c >= 0x80) return 2;

		}

	} else if (GB(s[0], 4, 4) == 14) {

		if (IsUtf8Part(s[1]) && IsUtf8Part(s[2])) {

			/* Triple byte character: 1110xxxx 10xxxxxx 10xxxxxx */

			*c = GB(s[0], 0, 4) << 12 | GB(s[1], 0, 6) << 6 | GB(s[2], 0, 6);

			if (*c >= 0x800) return 3;

		}

	} else if (GB(s[0], 3, 5) == 30) {

		if (IsUtf8Part(s[1]) && IsUtf8Part(s[2]) && IsUtf8Part(s[3])) {

			/* 4 byte character: 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx */

			*c = GB(s[0], 0, 3) << 18 | GB(s[1], 0, 6) << 12 | GB(s[2], 0, 6) << 6 | GB(s[3], 0, 6);

			if (*c >= 0x10000 && *c <= 0x10FFFF) return 4;

		}

	}

	//DEBUG(misc, 1, "[utf8] invalid UTF-8 sequence");

	*c = '?';

	return 1;

}

/* Encode a unicode character and place it in the buffer

 * @param buf Buffer to place character.

 * @param c   Unicode character to encode.

 * @return Number of characters in the encoded sequence.

 */

size_t Utf8Encode(char *buf, WChar c)

{

	if (c < 0x80) {

		*buf = c;

		return 1;

	} else if (c < 0x800) {

		*buf++ = 0xC0 + GB(c,  6, 5);

		*buf   = 0x80 + GB(c,  0, 6);

		return 2;

	} else if (c < 0x10000) {

		*buf++ = 0xE0 + GB(c, 12, 4);

		*buf++ = 0x80 + GB(c,  6, 6);

		*buf   = 0x80 + GB(c,  0, 6);

		return 3;

	} else if (c < 0x110000) {

		*buf++ = 0xF0 + GB(c, 18, 3);

		*buf++ = 0x80 + GB(c, 12, 6);

		*buf++ = 0x80 + GB(c,  6, 6);

		*buf   = 0x80 + GB(c,  0, 6);

		return 4;

	}

	//DEBUG(misc, 1, "[utf8] can't UTF-8 encode value 0x%X", c);

	*buf = '?';

	return 1;

}