// The contents of this file are subject to the BOINC Public License
// Version 1.0 (the "License"); you may not use this file except in
// compliance with the License. You may obtain a copy of the License at
// http://boinc.berkeley.edu/license_1.0.txt
//
// Software distributed under the License is distributed on an "AS IS"
// basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
// License for the specific language governing rights and limitations
// under the License.
//
// The Original Code is the Berkeley Open Infrastructure for Network Computing.
//
// The Initial Developer of the Original Code is the SETI@home project.
// Portions created by the SETI@home project are Copyright (C) 2002
// University of California at Berkeley. All Rights Reserved.
//
// Contributor(s):
//

#ifndef UTIL_H
#define UTIL_H

#include <cstdlib>
#include <ctime>
#include <cmath>
#include <cctype>
#include <cstring>
#include <algorithm>
#include <string>

#if !defined(HAVE_STRLCPY)
extern size_t strlcpy(char*, const char*, size_t);
#endif

#if !defined(HAVE_STRLCAT)
extern size_t strlcat(char *dst, const char *src, size_t size);
#endif

extern int ndays_to_string(double x, int smallest_timescale, char *buf);
extern void nbytes_to_string(double nbytes, double total_bytes, char* str, int len);
extern double dtime();
extern void boinc_sleep(double);
extern int parse_command_line( char *, char ** );
extern void c2x(char *what);
extern void strip_whitespace(char *str);
extern void strip_whitespace(std::string&);
extern void unescape_url(char *url);
extern void escape_url(char *in, char*out);
extern void escape_url_readable(char* in, char* out);
extern bool invalid_url(char*);
extern void canonicalize_master_url(char *url);
extern void safe_strncpy(char*, const char*, int);
#define safe_strcpy(x, y) safe_strncpy(x, y, sizeof(x))
#define safe_strcat(x, y) if (strlen(x)+strlen(y)<sizeof(x)) strcat(x, y)
extern char* time_to_string(double);
std::string timediff_format(double);
int read_file_string(const char* pathname, std::string& result);

inline bool ends_with(std::string const& s, std::string const& suffix) {
    return
        s.size()>=suffix.size() &&
        s.substr(s.size()-suffix.size()) == suffix;
}

inline bool starts_with(std::string const& s, std::string const& prefix) {
    return s.substr(0, prefix.size()) == prefix;
}

// http://lists.debian.org/debian-gcc/2002/debian-gcc-200204/msg00092.html
inline void downcase_string(
    std::string::iterator begin, std::string::iterator end, std::string::iterator src
) {
	std::transform(begin, end, src, (int(*)(int))tolower);
}

inline void downcase_string(std::string& w) {
    downcase_string(w.begin(), w.end(), w.begin());
}

// NOTE: use #include <functional>   to get max,min

#define SECONDS_PER_DAY 86400

static inline double drand() {
    return (double)rand()/(double)RAND_MAX;
}

// return a random integer in the range [rmin,rmax)
static inline double rand_range(double rmin, double rmax)
{
    if (rmin < rmax)
        return drand() * (rmax-rmin) + rmin;
    else
        return rmin;
}

// return a random integer in the range [MIN,min(e^n,MAX))
double calculate_exponential_backoff(
    const char* debug_descr, int n, double MIN, double MAX,
    double factor=1.0
);
extern bool debug_fake_exponential_backoff;


#ifdef _WIN32
#include <windows.h>
char* windows_error_string(char* pszBuf, int iSize);
char* windows_format_error_string(
    unsigned long dwError, char* pszBuf, int iSize
);
int boinc_thread_cpu_time(HANDLE thread_handle, double& cpu, double& ws);
#endif

extern void update_average(double, double, double, double&, double&);

// convert filename to path in a hierarchical directory system
//
extern int dir_hier_path(
    const char* filename, const char* root, int fanout, char* result,
    bool create=false
);

// convert filename to URL in a hierarchical directory system
//
extern int dir_hier_url(
    const char* filename, const char* root, int fanout, char* result
);

extern int boinc_calling_thread_cpu_time(double&, double&);

#endif