/******************************************************************************
 *
 *  utilstr.cpp -	String utility functions
 *
 * $Id$
 *
 * Copyright 1997-2013 CrossWire Bible Society (http://www.crosswire.org)
 *	CrossWire Bible Society
 *	P. O. Box 2528
 *	Tempe, AZ  85280-2528
 *
 * 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 version 2.
 *
 * 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.
 *
 */

#include <utilstr.h>
#include <ctype.h>
#include <string.h>

#include <sysdata.h>
#include <swlog.h>
#include <swbuf.h>


SWORD_NAMESPACE_START

const unsigned char SW_toupper_array[256] = {
	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
	0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
	0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
	0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27,
	0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37,
	0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
	0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
	0x58, 0x59, 0x5a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
	0x60, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47,
	0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f,
	0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57,
	0x58, 0x59, 0x5a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87,
	0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97,
	0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7,
	0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7,
	0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
	0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7,
	0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7,
	0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xf7,
	0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xff
};


/******************************************************************************
 * stdstr - clones a string
 *
 * ENT:	ipstr	- pointer to a string pointer to set if necessary
 *	istr	- string to set to *ipstr
 *			0 - only get
 *
 * RET:	*ipstr
 */

char *stdstr(char **ipstr, const char *istr, unsigned int memPadFactor) {
	if (*ipstr)
		delete [] *ipstr;
	if (istr) {
		int len = strlen(istr) + 1;
		*ipstr = new char [ len * memPadFactor ];
		memcpy(*ipstr, istr, len);
	}
	else *ipstr = 0;
	return *ipstr;
}


/******************************************************************************
 * strstrip - Removes leading and trailing spaces from a string
 *
 * ENT:	istr	- string pointer to strip
 *
 * RET:	*istr
 */

char *strstrip(char *istr) {
	char *tmp = istr;
	char *rtmp;

	int len = strlen(istr);
	if (len < 1)
		return istr;
	rtmp = istr + (len - 1);
	
	while ((rtmp > istr)&&((*rtmp == ' ')||(*rtmp == '\t')||(*rtmp == 10)||(*rtmp == 13))) *(rtmp--) = 0;
	while ((*tmp == ' ')||(*tmp == '\t')||(*tmp == 10)||(*tmp == 13)) tmp++;
	memmove(istr, tmp, (rtmp - tmp) + 1);
	istr[(rtmp - tmp) + 1] = 0;

	return istr;
}


/******************************************************************************
 * stristr - Scans a string for the occurrence of a given substring, no case
 *
 * ENT:	scans s1 for the first occurrence of the substring s2, ingnoring case
 *
 * RET:	a pointer to the element in s1, where s2 begins (points to s2 in s1).
 *			If s2 does not occur in s1, returns null.
 */

const char *stristr(const char *s1, const char *s2) {
	int tLen = strlen(s2);
	int cLen = strlen(s1);
	char *target = new char [ tLen + 1 ];
	int i, j;
	const char *retVal = 0;

	strcpy(target, s2);
	for (i = 0; i < tLen; i++)
		target[i] = SW_toupper(target[i]);

	for (i = 0; i < (cLen - tLen)+1; i++) {
		if (SW_toupper(s1[i]) == (unsigned char)*target) {
			for (j = 1; j < tLen; j++) {
				if (SW_toupper(s1[i+j]) != (unsigned char)target[j])
					break;
			}
			if (j == tLen) {
				retVal = s1+i;
				break;
			}
		}
	}
	delete [] target;
	return retVal;
}

/******************************************************************************
 * strnicmp - compares the first n bytes of 2 strings ignoring case
 *
 * ENT:	compares s1 to s2 comparing the first n byte ingnoring case
 *
 * RET:	same as strcmp
 */

int strnicmp(const char *s1, const char *s2, int len) {
	int tLen = strlen(s2);
	int cLen = strlen(s1);
	char diff;
	int i;
	for (i = 0; ((i < len) && (i < tLen) && (i < cLen)); i++) {
		if ((diff = SW_toupper(*s1) - SW_toupper(*s2)))
			return diff;
	s1++;
	s2++;
	}
	return (i < len) ? cLen - tLen : 0;
}

int stricmp(const char *s1, const char *s2) {
#if defined(__GNUC__)
	return ::strcasecmp(s1, s2);
#else
 #if defined(_WIN32_WCE)
	return ::_stricmp(s1, s2);
 #else
	return ::stricmp(s1, s2);
 #endif
#endif
}


/******************************************************************************
 * getUniCharFromUTF8 - retrieves the next Unicode codepoint from a UTF8 string
 * 					and increments buf to start of next codepoint
 *
 * ENT:	buf - address of a utf8 buffer
 *
 * RET:	buf - incremented past last byte used in computing the current codepoint
 * 		unicode codepoint value (0 with buf incremented is invalid UTF8 byte
 */

__u32 getUniCharFromUTF8(const unsigned char **buf) {
	__u32 ch = 0;
	unsigned char multibuf[7];

	//case: We're at the end
	if (!(**buf)) {
		return ch;
	}

	//case: ANSI
	if (!(**buf & 128)) {
		ch = **buf;
		(*buf)++;
		return ch;
	}

	//case: Invalid UTF-8 (illegal continuing byte in initial position)
	if ((**buf & 128) && (!(**buf & 64))) {
		(*buf)++;
		return ch;
	}

	//case: 2+ byte codepoint
	multibuf[0] = **buf;
	multibuf[0] <<= 1;
	int subsequent;
	for (subsequent = 1; (multibuf[0] & 128) && (subsequent < 7); subsequent++) {
		multibuf[0] <<= 1;
		multibuf[subsequent] = (*buf)[subsequent];
		multibuf[subsequent] &= 63;
		// subsequent byte did not begin with 10XXXXXX
		// move our buffer to here and error out
		if (((*buf)[subsequent] - multibuf[subsequent]) != 128) {
			*buf += subsequent;
			return 0;
		}
		ch <<= 6;
		ch |= multibuf[subsequent];
	}
	subsequent--;
	multibuf[0] <<= 1;
	char significantFirstBits = 8 - (2+subsequent);
	
	ch |= (((__s16)multibuf[0]) << (((6*subsequent)+significantFirstBits)-8));
	*buf += (subsequent+1);
	return ch;
}


SWBuf getUTF8FromUniChar(__u32 uchar) {
	SWBuf retVal("", 7);
	unsigned int i;

	if (uchar < 0x80) {
		retVal.append((unsigned char)uchar);
		retVal.setSize(1);
	}
	else if (uchar < 0x800) {
		retVal.setSize(2);
		i = uchar & 0x3f;
		retVal[1] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x1f;
		retVal[0] = (unsigned char)(0xc0 | i);
	}
	else if (uchar < 0x10000) {
		retVal.setSize(3);
		i = uchar & 0x3f;
		retVal[2] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[1] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x0f;
		retVal[0] = (unsigned char)(0xe0 | i);
	}
	else if (uchar < 0x200000) {
		retVal.setSize(4);
		i = uchar & 0x3f;
		retVal[3] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[2] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[1] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x07;
		retVal[0] = (unsigned char)(0xf0 | i);
	}
	else if (uchar < 0x4000000) {
		retVal.setSize(5);
		i = uchar & 0x3f;
		retVal[4] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[3] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[2] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[1] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x03;
		retVal[0] = (unsigned char)(0xf8 | i);
	}
	else if (uchar < 0x80000000) {
		retVal.setSize(6);
		i = uchar & 0x3f;
		retVal[5] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[4] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[3] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[2] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x3f;
		retVal[1] = (unsigned char)(0x80 | i);
		uchar >>= 6;

		i = uchar & 0x01;
		retVal[0] = (unsigned char)(0xfc | i);
	}

	return retVal;
}


SWBuf assureValidUTF8(const char *buf) {

	SWBuf myCopy = buf;
	const unsigned char *b = (const unsigned char *)myCopy.c_str();
	const unsigned char *q = 0;
	bool invalidChar = false;
	while (*b) {
		q = b;
		if (!getUniCharFromUTF8(&b)) {
			long len = b - q;
			if (len) {
				invalidChar = true;
				for (long start = q - (const unsigned char *)myCopy.c_str(); len; len--) {
					myCopy[start+len-1] = 0x1a;	// unicode replacement character
				}
				
			}
		}
	}
	if (invalidChar) {
//		SWLog::getSystemLog()->logWarning("Changing invalid UTF-8 string (%s) to (%s)\n", buf, myCopy.c_str());
	}
	return myCopy;
}


/****
 * This can be called to convert a UTF8 stream to an SWBuf which manages
 *	a wchar_t[]
 *	access buffer with (wchar_t *)SWBuf::getRawData();
 * 
 */
SWBuf utf8ToWChar(const char *buf) {

	const char *q = 0;
	SWBuf wcharBuf;
	while (*buf) {
		q = buf;
		wchar_t wc = getUniCharFromUTF8((const unsigned char **)&buf);
		if (!wc) {
			// if my buffer was advanced but nothing was converted, I had invalid data
			if (buf - q) {
				// invalid bytes in UTF8 stream
				wcharBuf.append((wchar_t)0x1a);		// unicode replacement character
			}
		}
		else wcharBuf.append(wc);
	}
	return wcharBuf;
}


/****
 * This can be called to convert a wchar_t[] to a UTF-8 SWBuf
 * 
 */
SWBuf wcharToUTF8(const wchar_t *buf) {

	SWBuf utf8Buf;
	while (*buf) {
		utf8Buf.append(getUTF8FromUniChar(*buf++));
	}
	return utf8Buf;
}


SWORD_NAMESPACE_END