/*
Minetest
Copyright (C) 2013 celeron55, Perttu Ahola <celeron55@gmail.com>

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.

You should have received a copy of the GNU Lesser 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.
*/

/*
	Random portability stuff
*/

#pragma once

#ifdef _WIN32
	#ifdef _WIN32_WINNT
		#undef _WIN32_WINNT
	#endif
	#define _WIN32_WINNT 0x0501 // We need to do this before any other headers
		// because those might include sdkddkver.h which defines _WIN32_WINNT if not already set
#endif

#include <string>
#include <vector>
#include "irrlicht.h"
#include "irrlichttypes.h" // u32
#include "irrlichttypes_extrabloated.h"
#include "debug.h"
#include "constants.h"
#include "gettime.h"

#ifdef _MSC_VER
	#define SWPRINTF_CHARSTRING L"%S"
#else
	#define SWPRINTF_CHARSTRING L"%s"
#endif

//currently not needed
//template<typename T> struct alignment_trick { char c; T member; };
//#define ALIGNOF(type) offsetof (alignment_trick<type>, member)

#ifdef _WIN32
	#include <windows.h>

	#define sleep_ms(x) Sleep(x)
#else
	#include <unistd.h>
	#include <cstdint> //for uintptr_t

	// Use standard Posix macro for Linux
	#if (defined(linux) || defined(__linux)) && !defined(__linux__)
		#define __linux__
	#endif
	#if (defined(__linux__) || defined(__GNU__)) && !defined(_GNU_SOURCE)
		#define _GNU_SOURCE
	#endif

	#define sleep_ms(x) usleep(x*1000)
#endif

#ifdef _MSC_VER
	#define ALIGNOF(x) __alignof(x)
	#define strtok_r(x, y, z) strtok_s(x, y, z)
	#define strtof(x, y) (float)strtod(x, y)
	#define strtoll(x, y, z) _strtoi64(x, y, z)
	#define strtoull(x, y, z) _strtoui64(x, y, z)
	#define strcasecmp(x, y) stricmp(x, y)
	#define strncasecmp(x, y, n) strnicmp(x, y, n)
#else
	#define ALIGNOF(x) __alignof__(x)
#endif

#ifdef __MINGW32__
	#define strtok_r(x, y, z) mystrtok_r(x, y, z)
#endif

// strlcpy is missing from glibc.  thanks a lot, drepper.
// strlcpy is also missing from AIX and HP-UX because they aim to be weird.
// We can't simply alias strlcpy to MSVC's strcpy_s, since strcpy_s by
// default raises an assertion error and aborts the program if the buffer is
// too small.
#if defined(__FreeBSD__) || defined(__NetBSD__)    || \
	defined(__OpenBSD__) || defined(__DragonFly__) || \
	defined(__APPLE__)   ||                           \
	defined(__sun)       || defined(sun)           || \
	defined(__QNX__)     || defined(__QNXNTO__)
	#define HAVE_STRLCPY
#endif

// So we need to define our own.
#ifndef HAVE_STRLCPY
	#define strlcpy(d, s, n) mystrlcpy(d, s, n)
#endif

#define PADDING(x, y) ((ALIGNOF(y) - ((uintptr_t)(x) & (ALIGNOF(y) - 1))) & (ALIGNOF(y) - 1))

#if defined(__APPLE__)
	#include <mach-o/dyld.h>
	#include <CoreFoundation/CoreFoundation.h>
#endif

#ifndef _WIN32 // Posix
	#include <sys/time.h>
	#include <ctime>

#if defined(__MACH__) && defined(__APPLE__)
		#include <mach/clock.h>
		#include <mach/mach.h>
	#endif
#endif

namespace porting
{

/*
	Signal handler (grabs Ctrl-C on POSIX systems)
*/

void signal_handler_init();
// Returns a pointer to a bool.
// When the bool is true, program should quit.
bool * signal_handler_killstatus();

/*
	Path of static data directory.
*/
extern std::string path_share;

/*
	Directory for storing user data. Examples:
	Windows: "C:\Documents and Settings\user\Application Data\<PROJECT_NAME>"
	Linux: "~/.<PROJECT_NAME>"
	Mac: "~/Library/Application Support/<PROJECT_NAME>"
*/
extern std::string path_user;

/*
	Path to gettext locale files
*/
extern std::string path_locale;

/*
	Path to directory for storing caches.
*/
extern std::string path_cache;

/*
	Get full path of stuff in data directory.
	Example: "stone.png" -> "../data/stone.png"
*/
std::string getDataPath(const char *subpath);

/*
	Move cache folder from path_user to the
	system cache location if possible.
*/
void migrateCachePath();

/*
	Initialize path_*.
*/
void initializePaths();

/*
	Return system information
	e.g. "Linux/3.12.7 x86_64"
*/
std::string get_sysinfo();


// Monotonic counter getters.

#ifdef _WIN32 // Windows

extern double perf_freq;

inline u64 os_get_time(double mult)
{
	LARGE_INTEGER t;
	QueryPerformanceCounter(&t);
	return static_cast<double>(t.QuadPart) / (perf_freq / mult);
}

// Resolution is <1us.
inline u64 getTimeS() { return os_get_time(1); }
inline u64 getTimeMs() { return os_get_time(1000); }
inline u64 getTimeUs() { return os_get_time(1000*1000); }
inline u64 getTimeNs() { return os_get_time(1000*1000*1000); }

#else // Posix

inline void os_get_clock(struct timespec *ts)
{
#if defined(__MACH__) && defined(__APPLE__)
// From http://stackoverflow.com/questions/5167269/clock-gettime-alternative-in-mac-os-x
// OS X does not have clock_gettime, use clock_get_time
	clock_serv_t cclock;
	mach_timespec_t mts;
	host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
	clock_get_time(cclock, &mts);
	mach_port_deallocate(mach_task_self(), cclock);
	ts->tv_sec = mts.tv_sec;
	ts->tv_nsec = mts.tv_nsec;
#elif defined(CLOCK_MONOTONIC_RAW)
	clock_gettime(CLOCK_MONOTONIC_RAW, ts);
#elif defined(_POSIX_MONOTONIC_CLOCK)
	clock_gettime(CLOCK_MONOTONIC, ts);
#else
	struct timeval tv;
	gettimeofday(&tv, NULL);
	TIMEVAL_TO_TIMESPEC(&tv, ts);
#endif
}

inline u64 getTimeS()
{
	struct timespec ts;
	os_get_clock(&ts);
	return ts.tv_sec;
}

inline u64 getTimeMs()
{
	struct timespec ts;
	os_get_clock(&ts);
	return ((u64) ts.tv_sec) * 1000LL + ((u64) ts.tv_nsec) / 1000000LL;
}

inline u64 getTimeUs()
{
	struct timespec ts;
	os_get_clock(&ts);
	return ((u64) ts.tv_sec) * 1000000LL + ((u64) ts.tv_nsec) / 1000LL;
}

inline u64 getTimeNs()
{
	struct timespec ts;
	os_get_clock(&ts);
	return ((u64) ts.tv_sec) * 1000000000LL + ((u64) ts.tv_nsec);
}

#endif

inline u64 getTime(TimePrecision prec)
{
	switch (prec) {
	case PRECISION_SECONDS: return getTimeS();
	case PRECISION_MILLI:   return getTimeMs();
	case PRECISION_MICRO:   return getTimeUs();
	case PRECISION_NANO:    return getTimeNs();
	}
	FATAL_ERROR("Called getTime with invalid time precision");
}

/**
 * Delta calculation function arguments.
 * @param old_time_ms old time for delta calculation
 * @param new_time_ms new time for delta calculation
 * @return positive delta value
 */
inline u64 getDeltaMs(u64 old_time_ms, u64 new_time_ms)
{
	if (new_time_ms >= old_time_ms) {
		return (new_time_ms - old_time_ms);
	}

	return (old_time_ms - new_time_ms);
}

inline const char *getPlatformName()
{
	return
#if defined(ANDROID)
	"Android"
#elif defined(__linux__)
	"Linux"
#elif defined(_WIN32) || defined(_WIN64)
	"Windows"
#elif defined(__DragonFly__) || defined(__FreeBSD__) || \
		defined(__NetBSD__) || defined(__OpenBSD__)
	"BSD"
#elif defined(__APPLE__) && defined(__MACH__)
	#if TARGET_OS_MAC
		"OSX"
	#elif TARGET_OS_IPHONE
		"iOS"
	#else
		"Apple"
	#endif
#elif defined(_AIX)
	"AIX"
#elif defined(__hpux)
	"HP-UX"
#elif defined(__sun) || defined(sun)
	#if defined(__SVR4)
		"Solaris"
	#else
		"SunOS"
	#endif
#elif defined(__HAIKU__)
	"Haiku"
#elif defined(__CYGWIN__)
	"Cygwin"
#elif defined(__unix__) || defined(__unix)
	#if defined(_POSIX_VERSION)
		"Posix"
	#else
		"Unix"
	#endif
#else
	"?"
#endif
	;
}

bool secure_rand_fill_buf(void *buf, size_t len);

// This attaches to the parents process console, or creates a new one if it doesnt exist.
void attachOrCreateConsole();

int mt_snprintf(char *buf, const size_t buf_size, const char *fmt, ...);

/**
 * Opens URL in default web browser
 *
 * Must begin with http:// or https://, and not contain any new lines
 *
 * @param url The URL
 * @return true on success, false on failure
 */
bool open_url(const std::string &url);

/**
 * Opens a directory in the default file manager
 *
 * The directory must exist.
 *
 * @param path Path to directory
 * @return true on success, false on failure
 */
bool open_directory(const std::string &path);

} // namespace porting

#ifdef __ANDROID__
#include "porting_android.h"
#endif
