/*
 * Hedgewars, a free turn based strategy game
 * Copyright (C) 2012 Simeon Maxein <smaxein@googlemail.com>
 *
 * 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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

#include "util.h"
#include "logging.h"

#include <stddef.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <ctype.h>
#include <limits.h>

char *flib_asprintf(const char *fmt, ...) {
	va_list argp;
	va_start(argp, fmt);
	char *result = flib_vasprintf(fmt, argp);
	va_end(argp);
	return result;
}

char *flib_vasprintf(const char *fmt, va_list args) {
    char *result = NULL;
	if(!log_badargs_if(fmt==NULL)) {
        va_list args_copy;
        va_copy(args_copy, args);

        int requiredSize = vsnprintf(NULL, 0, fmt, args_copy)+1;					// Figure out how much memory we need,

        va_end(args_copy);

        if(!log_e_if(requiredSize<0, "Error formatting string with template \"%s\"", fmt)) {
			char *tmpbuf = flib_malloc(requiredSize);						// allocate it
            if(tmpbuf && vsnprintf(tmpbuf, requiredSize, fmt, args)>=0) {	// and then do the actual formatting.
				result = tmpbuf;
				tmpbuf = NULL;
			}
			free(tmpbuf);
		}
	}
	return result;
}

char *flib_join(char **parts, int partCount, const char *delimiter) {
	char *result = NULL;
	if(!log_badargs_if2(parts==NULL, delimiter==NULL)) {
		size_t totalSize = 1;
		size_t delimLen = strlen(delimiter);
		for(int i=0; i<partCount; i++) {
			totalSize += strlen(parts[i]) + delimLen;
		}
		result = flib_malloc(totalSize);

		if(result) {
			size_t outpos = 0;
			for(int i=0; i<partCount; i++) {
				if(i>0) {
					strcpy(result+outpos, delimiter);
					outpos += delimLen;
				}
				strcpy(result+outpos, parts[i]);
				outpos += strlen(parts[i]);
			}
		}
	}
	return result;
}

char *flib_strdupnull(const char *str) {
	return str==NULL ? NULL : flib_asprintf("%s", str);
}

void *flib_bufdupnull(const void *buf, size_t size) {
	void *result = NULL;
	if(!log_badargs_if(buf==NULL && size>0)) {
		result = flib_malloc(size);
		if(result) {
			memcpy(result, buf, size);
		}
	}
	return result;
}

void *flib_malloc(size_t size) {
	void *result = malloc(size);
	if(!result && size>0) {
		flib_log_e("Out of memory trying to malloc %zu bytes.", size);
	}
	return result;
}

void *flib_calloc(size_t count, size_t elementsize) {
	void *result = calloc(count, elementsize);
	if(!result && count>0 && elementsize>0) {
		flib_log_e("Out of memory trying to calloc %zu objects of %zu bytes each.", count, elementsize);
	}
	return result;
}

void *flib_realloc(void *ptr, size_t size) {
	void *result = realloc(ptr, size);
	if(!result && size>0) {
		flib_log_e("Out of memory trying to realloc %zu bytes.", size);
	}
	return result;
}

static bool isAsciiAlnum(char c) {
	return (c>='0' && c<='9') || (c>='a' && c <='z') || (c>='A' && c <='Z');
}

char *flib_urlencode(const char *inbuf) {
	return flib_urlencode_pred(inbuf, isAsciiAlnum);
}

static size_t countCharsToEscape(const char *inbuf, bool (*needsEscaping)(char c)) {
	size_t result = 0;
	for(const char *c=inbuf; *c; c++) {
		if(needsEscaping(*c)) {
			result++;
		}
	}
	return result;
}

char *flib_urlencode_pred(const char *inbuf, bool (*needsEscaping)(char c)) {
	char *result = NULL;
	if(inbuf && !log_badargs_if(needsEscaping == NULL)) {
		size_t insize = strlen(inbuf);
		if(!log_e_if(insize > SIZE_MAX/4, "String too long: %zu bytes.", insize)) {
			size_t escapeCount = countCharsToEscape(inbuf, needsEscaping);
			result = flib_malloc(insize + escapeCount*2 + 1);
		}
		if(result) {
			char *out = result;
			for(const char *in = inbuf; *in; in++) {
				if(!needsEscaping(*in)) {
					*out = *in;
					out++;
				} else {
					snprintf(out, 4, "%%%02x", (unsigned)(*(uint8_t*)in));
					out += 3;
				}
			}
			*out = 0;
		}
	}
	return result;
}

char *flib_urldecode(const char *inbuf) {
	if(!inbuf) {
		return NULL;
	}
	char *outbuf = flib_malloc(strlen(inbuf)+1);
	if(!outbuf) {
		return NULL;
	}

    size_t inpos = 0, outpos = 0;
    while(inbuf[inpos]) {
        if(inbuf[inpos] == '%' && isxdigit(inbuf[inpos+1]) && isxdigit(inbuf[inpos+2])) {
            char temp[3] = {inbuf[inpos+1],inbuf[inpos+2],0};
            outbuf[outpos++] = strtol(temp, NULL, 16);
            inpos += 3;
        } else {
        	outbuf[outpos++] = inbuf[inpos++];
        }
    }
    outbuf[outpos] = 0;
    char *shrunk = realloc(outbuf, outpos+1);
    return shrunk ? shrunk : outbuf;
}

bool flib_contains_dir_separator(const char *str) {
	if(!log_badargs_if(!str)) {
		for(;*str;str++) {
			if(*str=='\\' || *str=='/') {
				return true;
			}
		}
	}
	return false;
}

bool flib_strempty(const char *str) {
	return !str || !*str;
}

int flib_gets(char *str, size_t strlen) {
	if(fgets(str, strlen, stdin)) {
		for(char *s=str; *s; s++) {
			if(*s=='\r' || *s=='\n') {
				*s = 0;
				break;
			}
		}
		return 0;
	}
	return -1;
}