/*
 * Copyright (c) 2008-2021 Jonathan Schleifer <js@nil.im>
 *
 * All rights reserved.
 *
 * This file is part of ObjFW. It may be distributed under the terms of the
 * Q Public License 1.0, which can be found in the file LICENSE.QPL included in
 * the packaging of this file.
 *
 * Alternatively, it may be distributed under the terms of the GNU General
 * Public License, either version 2 or 3, which can be found in the file
 * LICENSE.GPLv2 or LICENSE.GPLv3 respectively included in the packaging of this
 * file.
 */

#define __NO_EXT_QNX

#include "config.h"

#include <limits.h>	/* include any libc header to get the libc defines */

#include "unistd_wrapper.h"

#include "platform.h"

#ifdef HAVE_SYS_UTSNAME_H
# include <sys/utsname.h>
#endif
#if defined(OF_MACOS) || defined(OF_NETBSD)
# include <sys/sysctl.h>
#endif

#if defined(OF_AMIGAOS4)
# include <exec/exectags.h>
# include <proto/exec.h>
#elif defined(OF_MORPHOS)
# include <exec/system.h>
# include <proto/exec.h>
#endif

#import "OFSystemInfo.h"
#import "OFApplication.h"
#import "OFArray.h"
#import "OFDictionary.h"
#import "OFLocale.h"
#import "OFString.h"

#import "OFNotImplementedException.h"

#import "once.h"

#if defined(OF_MACOS) || defined(OF_IOS)
# ifdef HAVE_SYSDIR_H
#  include <sysdir.h>
# endif
#endif
#ifdef OF_WINDOWS
# include <windows.h>
#endif
#ifdef OF_HAIKU
# include <FindDirectory.h>
#endif
#ifdef OF_QNX
# include <sys/syspage.h>
#endif

#if defined(OF_MACOS) || defined(OF_IOS)
/*
 * These have been dropped from newer iOS SDKs, however, their replacements are
 * not available on iOS < 10. This means it's impossible to search for the
 * paths when using a new SDK while targeting iOS 9 or earlier. To work around
 * this, we define those manually, only to be used when the replacements are
 * not available at runtime.
 */

typedef enum {
	NSLibraryDirectory = 5,
	NSApplicationSupportDirectory = 14
} NSSearchPathDirectory;

typedef enum {
	NSUserDomainMask = 1
} NSSearchPathDomainMask;

typedef unsigned int NSSearchPathEnumerationState;

extern NSSearchPathEnumerationState NSStartSearchPathEnumeration(
    NSSearchPathDirectory, NSSearchPathDomainMask);
extern NSSearchPathEnumerationState NSGetNextSearchPathEnumeration(
    NSSearchPathEnumerationState, char *);
#endif

#if defined(OF_X86_64) || defined(OF_X86)
struct x86_regs {
	uint32_t eax, ebx, ecx, edx;
};
#endif

static size_t pageSize = 4096;
static size_t numberOfCPUs = 1;
static OFString *operatingSystemName = nil;
static OFString *operatingSystemVersion = nil;

static void
initOperatingSystemName(void)
{
#if defined(OF_IOS)
	operatingSystemName = @"iOS";
#elif defined(OF_MACOS)
	operatingSystemName = @"macOS";
#elif defined(OF_WINDOWS)
	operatingSystemName = @"Windows";
#elif defined(OF_ANDROID)
	operatingSystemName = @"Android";
#elif defined(OF_AMIGAOS_M68K)
	operatingSystemName = @"AmigaOS";
#elif defined(OF_MORPHOS)
	operatingSystemName = @"MorphOS";
#elif defined(OF_AMIGAOS4)
	operatingSystemName = @"AmigaOS 4";
#elif defined(OF_WII)
	operatingSystemName = @"Nintendo Wii";
#elif defined(NINTENDO_3DS)
	operatingSystemName = @"Nintendo 3DS";
#elif defined(OF_NINTENDO_DS)
	operatingSystemName = @"Nintendo DS";
#elif defined(OF_PSP)
	operatingSystemName = @"PlayStation Portable";
#elif defined(OF_MSDOS)
	operatingSystemName = @"MS-DOS";
#elif defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME)
	struct utsname utsname;

	if (uname(&utsname) != 0)
		return;

	operatingSystemName = [[OFString alloc]
	    initWithCString: utsname.sysname
		   encoding: [OFLocale encoding]];
#endif
}

static void
initOperatingSystemVersion(void)
{
#if defined(OF_IOS) || defined(OF_MACOS)
# ifdef OF_HAVE_FILES
	void *pool = objc_autoreleasePoolPush();

	@try {
		OFDictionary *propertyList = [[OFString
		    stringWithContentsOfFile: @"/System/Library/CoreServices/"
		                              @"SystemVersion.plist"]
		    objectByParsingPropertyList];

		operatingSystemVersion = [[propertyList
		    objectForKey: @"ProductVersion"] copy];
	} @finally {
		objc_autoreleasePoolPop(pool);
	}
# endif
#elif defined(OF_WINDOWS)
# ifdef OF_HAVE_FILES
	void *pool = objc_autoreleasePoolPush();

	@try {
		of_string_encoding_t encoding = [OFLocale encoding];
		char systemDir[PATH_MAX];
		UINT systemDirLen;
		OFString *systemDirString;
		const char *path;
		void *buffer;
		DWORD bufferLen;

		systemDirLen = GetSystemDirectoryA(systemDir, PATH_MAX);
		if (systemDirLen == 0)
			return;

		systemDirString = [OFString stringWithCString: systemDir
						     encoding: encoding
						       length: systemDirLen];
		path = [[systemDirString stringByAppendingPathComponent:
		    @"kernel32.dll"] cStringWithEncoding: encoding];

		if ((bufferLen = GetFileVersionInfoSizeA(path, NULL)) == 0)
			return;
		if ((buffer = malloc(bufferLen)) == 0)
			return;

		@try {
			void *data;
			UINT dataLen;
			VS_FIXEDFILEINFO *info;

			if (!GetFileVersionInfoA(path, 0, bufferLen, buffer))
				return;

			if (!VerQueryValueA(buffer, "\\", &data, &dataLen) ||
			    dataLen < sizeof(info))
				return;

			info = (VS_FIXEDFILEINFO *)data;

			operatingSystemVersion = [[OFString alloc]
			    initWithFormat: @"%u.%u.%u",
					    HIWORD(info->dwProductVersionMS),
					    LOWORD(info->dwProductVersionMS),
					    HIWORD(info->dwProductVersionLS)];
		} @finally {
			free(buffer);
		}
	} @finally {
		objc_autoreleasePoolPop(pool);
	}
# endif
#elif defined(OF_ANDROID)
	/* TODO */
#elif defined(OF_MORPHOS)
	/* TODO */
#elif defined(OF_AMIGAOS4)
	/* TODO */
#elif defined(OF_AMIGAOS_M68K)
	/* TODO */
#elif defined(OF_WII) || defined(NINTENDO_3DS) || defined(OF_NINTENDO_DS) || \
    defined(OF_PSP) || defined(OF_MSDOS)
	/* Intentionally nothing */
#elif defined(HAVE_SYS_UTSNAME_H) && defined(HAVE_UNAME)
	struct utsname utsname;

	if (uname(&utsname) != 0)
		return;

	operatingSystemVersion = [[OFString alloc]
	    initWithCString: utsname.release
		   encoding: [OFLocale encoding]];
#endif
}

#if defined(OF_X86_64) || defined(OF_X86)
static OF_INLINE struct x86_regs OF_CONST_FUNC
x86_cpuid(uint32_t eax, uint32_t ecx)
{
	struct x86_regs regs;

# if defined(OF_X86_64) && defined(__GNUC__)
	__asm__ (
	    "cpuid"
	    : "=a"(regs.eax), "=b"(regs.ebx), "=c"(regs.ecx), "=d"(regs.edx)
	    : "a"(eax), "c"(ecx)
	);
# elif defined(OF_X86) && defined(__GNUC__)
	/*
	 * This workaround is required by older GCC versions when using -fPIC,
	 * as ebx is a special register in PIC code. Yes, GCC is indeed not
	 * able to just push a register onto the stack before the __asm__ block
	 * and to pop it afterwards.
	 */
	__asm__ (
	    "xchgl	%%ebx, %%edi\n\t"
	    "cpuid\n\t"
	    "xchgl	%%edi, %%ebx"
	    : "=a"(regs.eax), "=D"(regs.ebx), "=c"(regs.ecx), "=d"(regs.edx)
	    : "a"(eax), "c"(ecx)
	);
# else
	memset(&regs, 0, sizeof(regs));
# endif

	return regs;
}
#endif

@implementation OFSystemInfo
+ (void)initialize
{
	long tmp;

	if (self != [OFSystemInfo class])
		return;

#if defined(OF_WINDOWS)
	SYSTEM_INFO si;
	GetSystemInfo(&si);
	pageSize = si.dwPageSize;
	numberOfCPUs = si.dwNumberOfProcessors;
#elif defined(OF_QNX)
	if ((tmp = sysconf(_SC_PAGESIZE)) > 0)
		pageSize = tmp;
	numberOfCPUs = _syspage_ptr->num_cpu;
#else
# if defined(HAVE_SYSCONF) && defined(_SC_PAGESIZE)
	if ((tmp = sysconf(_SC_PAGESIZE)) > 0)
		pageSize = tmp;
# endif
# if defined(HAVE_SYSCONF) && defined(_SC_NPROCESSORS_CONF)
	if ((tmp = sysconf(_SC_NPROCESSORS_CONF)) > 0)
		numberOfCPUs = tmp;
# endif
#endif

	(void)tmp;
}

+ (instancetype)alloc
{
	OF_UNRECOGNIZED_SELECTOR
}

+ (size_t)pageSize
{
	return pageSize;
}

+ (size_t)numberOfCPUs
{
	return numberOfCPUs;
}

+ (OFString *)ObjFWVersion
{
	return @PACKAGE_VERSION;
}

+ (unsigned int)ObjFWVersionMajor
{
	return OBJFW_VERSION_MAJOR;
}

+ (unsigned int)ObjFWVersionMinor
{
	return OBJFW_VERSION_MINOR;
}

+ (OFString *)operatingSystemName
{
	static of_once_t onceControl = OF_ONCE_INIT;
	of_once(&onceControl, initOperatingSystemName);

	return operatingSystemName;
}

+ (OFString *)operatingSystemVersion
{
	static of_once_t onceControl = OF_ONCE_INIT;
	of_once(&onceControl, initOperatingSystemVersion);

	return operatingSystemVersion;
}

#ifdef OF_HAVE_FILES
+ (OFString *)userDataPath
{
# if defined(OF_MACOS) || defined(OF_IOS)
	char pathC[PATH_MAX];
	OFMutableString *path;

#  ifdef HAVE_SYSDIR_START_SEARCH_PATH_ENUMERATION
	/* (1) to disable dead code warning when it is not a weak symbol */
	if ((1) && &sysdir_start_search_path_enumeration != NULL) {
		sysdir_search_path_enumeration_state state;

		state = sysdir_start_search_path_enumeration(
		    SYSDIR_DIRECTORY_APPLICATION_SUPPORT,
		    SYSDIR_DOMAIN_MASK_USER);
		if (sysdir_get_next_search_path_enumeration(state, pathC) == 0)
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];
	} else {
#  endif
		NSSearchPathEnumerationState state;

		state = NSStartSearchPathEnumeration(
		    NSApplicationSupportDirectory, NSUserDomainMask);
		if (NSGetNextSearchPathEnumeration(state, pathC) == 0)
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];
#  ifdef HAVE_SYSDIR_START_SEARCH_PATH_ENUMERATION
	}
#  endif

	path = [OFMutableString stringWithUTF8String: pathC];
	if ([path hasPrefix: @"~"]) {
		OFDictionary *env = [OFApplication environment];
		OFString *home;

		if ((home = [env objectForKey: @"HOME"]) == nil)
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];

		[path deleteCharactersInRange: OFMakeRange(0, 1)];
		[path prependString: home];
	}

	[path makeImmutable];

	return path;
# elif defined(OF_WINDOWS)
	OFDictionary *env = [OFApplication environment];
	OFString *appData;

	if ((appData = [env objectForKey: @"APPDATA"]) == nil)
		@throw [OFNotImplementedException exceptionWithSelector: _cmd
								 object: self];

	return appData;
# elif defined(OF_HAIKU)
	char pathC[PATH_MAX];

	if (find_directory(B_USER_SETTINGS_DIRECTORY, 0, false,
	    pathC, PATH_MAX) != B_OK)
		@throw [OFNotImplementedException exceptionWithSelector: _cmd
								 object: self];

	return [OFString stringWithUTF8String: pathC];
# elif defined(OF_AMIGAOS)
	return @"PROGDIR:";
# else
	OFDictionary *env = [OFApplication environment];
	OFString *var;
	void *pool;

	if ((var = [env objectForKey: @"XDG_DATA_HOME"]) != nil &&
	    var.length > 0)
		return var;

	if ((var = [env objectForKey: @"HOME"]) == nil)
		@throw [OFNotImplementedException exceptionWithSelector: _cmd
								 object: self];

	pool = objc_autoreleasePoolPush();

	var = [[OFString pathWithComponents: [OFArray arrayWithObjects:
	    var, @".local", @"share", nil]] retain];

	objc_autoreleasePoolPop(pool);

	return [var autorelease];
# endif
}

+ (OFString *)userConfigPath
{
# if defined(OF_MACOS) || defined(OF_IOS)
	char pathC[PATH_MAX];
	OFMutableString *path;

#  ifdef HAVE_SYSDIR_START_SEARCH_PATH_ENUMERATION
	/* (1) to disable dead code warning when it is not a weak symbol */
	if ((1) && &sysdir_start_search_path_enumeration != NULL) {
		sysdir_search_path_enumeration_state state;

		state = sysdir_start_search_path_enumeration(
		    SYSDIR_DIRECTORY_LIBRARY, SYSDIR_DOMAIN_MASK_USER);
		if (sysdir_get_next_search_path_enumeration(state, pathC) == 0)
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];
	} else {
#  endif
		NSSearchPathEnumerationState state;

		state = NSStartSearchPathEnumeration(NSLibraryDirectory,
		    NSUserDomainMask);
		if (NSGetNextSearchPathEnumeration(state, pathC) == 0)
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];
#  ifdef HAVE_SYSDIR_START_SEARCH_PATH_ENUMERATION
	}
#  endif

	path = [OFMutableString stringWithUTF8String: pathC];
	if ([path hasPrefix: @"~"]) {
		OFDictionary *env = [OFApplication environment];
		OFString *home;

		if ((home = [env objectForKey: @"HOME"]) == nil)
			@throw [OFNotImplementedException
			    exceptionWithSelector: _cmd
					   object: self];

		[path deleteCharactersInRange: OFMakeRange(0, 1)];
		[path prependString: home];
	}

	[path appendString: @"/Preferences"];
	[path makeImmutable];

	return path;
# elif defined(OF_WINDOWS)
	OFDictionary *env = [OFApplication environment];
	OFString *appData;

	if ((appData = [env objectForKey: @"APPDATA"]) == nil)
		@throw [OFNotImplementedException exceptionWithSelector: _cmd
								 object: self];

	return appData;
# elif defined(OF_HAIKU)
	char pathC[PATH_MAX];

	if (find_directory(B_USER_SETTINGS_DIRECTORY, 0, false,
	    pathC, PATH_MAX) != B_OK)
		@throw [OFNotImplementedException exceptionWithSelector: _cmd
								 object: self];

	return [OFString stringWithUTF8String: pathC];
# elif defined(OF_AMIGAOS)
	return @"PROGDIR:";
# else
	OFDictionary *env = [OFApplication environment];
	OFString *var;

	if ((var = [env objectForKey: @"XDG_CONFIG_HOME"]) != nil &&
	    var.length > 0)
		return var;

	if ((var = [env objectForKey: @"HOME"]) == nil)
		@throw [OFNotImplementedException exceptionWithSelector: _cmd
								 object: self];

	return [var stringByAppendingPathComponent: @".config"];
# endif
}
#endif

+ (OFString *)CPUVendor
{
#if (defined(OF_X86_64) || defined(OF_X86)) && defined(__GNUC__)
	struct x86_regs regs = x86_cpuid(0, 0);
	uint32_t buffer[3];

	if (regs.eax == 0)
		return nil;

	buffer[0] = regs.ebx;
	buffer[1] = regs.edx;
	buffer[2] = regs.ecx;

	return [OFString stringWithCString: (char *)buffer
				  encoding: OF_STRING_ENCODING_ASCII
				    length: 12];
#else
	return nil;
#endif
}

+ (OFString *)CPUModel
{
#if (defined(OF_X86_64) || defined(OF_X86)) && defined(__GNUC__)
	uint32_t buffer[12];
	size_t i;

	i = 0;
	for (uint32_t eax = 0x80000002; eax <= 0x80000004; eax++) {
		struct x86_regs regs = x86_cpuid(eax, 0);

		buffer[i++] = regs.eax;
		buffer[i++] = regs.ebx;
		buffer[i++] = regs.ecx;
		buffer[i++] = regs.edx;
	}

	return [OFString stringWithCString: (char *)buffer
				  encoding: OF_STRING_ENCODING_ASCII];
#elif defined(OF_AMIGAOS4)
	CONST_STRPTR model, version;

	GetCPUInfoTags(GCIT_ModelString, &model,
	    GCIT_VersionString, &version, TAG_END);

	if (version != NULL)
		return [OFString stringWithFormat: @"%s V%s", model, version];
	else
		return [OFString stringWithCString: model
					  encoding: OF_STRING_ENCODING_ASCII];
#else
	return nil;
#endif
}

#if defined(OF_X86_64) || defined(OF_X86)
+ (bool)supportsMMX
{
	return (x86_cpuid(1, 0).edx & (1u << 23));
}

+ (bool)supportsSSE
{
	return (x86_cpuid(1, 0).edx & (1u << 25));
}

+ (bool)supportsSSE2
{
	return (x86_cpuid(1, 0).edx & (1u << 26));
}

+ (bool)supportsSSE3
{
	return (x86_cpuid(1, 0).ecx & (1u << 0));
}

+ (bool)supportsSSSE3
{
	return (x86_cpuid(1, 0).ecx & (1u << 9));
}

+ (bool)supportsSSE41
{
	return (x86_cpuid(1, 0).ecx & (1u << 19));
}

+ (bool)supportsSSE42
{
	return (x86_cpuid(1, 0).ecx & (1u << 20));
}

+ (bool)supportsAVX
{
	return (x86_cpuid(1, 0).ecx & (1u << 28));
}

+ (bool)supportsAVX2
{
	return x86_cpuid(0, 0).eax >= 7 && (x86_cpuid(7, 0).ebx & (1u << 5));
}

+ (bool)supportsAESNI
{
	return (x86_cpuid(1, 0).ecx & (1u << 25));
}

+ (bool)supportsSHAExtensions
{
	return (x86_cpuid(7, 0).ebx & (1u << 29));
}
#endif

#if defined(OF_POWERPC) || defined(OF_POWERPC64)
+ (bool)supportsAltiVec
{
# if defined(OF_MACOS)
	int name[2] = { CTL_HW, HW_VECTORUNIT }, value = 0;
	size_t length = sizeof(value);

	if (sysctl(name, 2, &value, &length, NULL, 0) == 0)
		return value;
# elif defined(OF_AMIGAOS4)
	uint32_t vectorUnit;

	GetCPUInfoTags(GCIT_VectorUnit, &vectorUnit, TAG_END);

	return (vectorUnit == VECTORTYPE_ALTIVEC);
# elif defined(OF_MORPHOS)
	uint32_t supportsAltiVec;

	if (NewGetSystemAttrs(&supportsAltiVec, sizeof(supportsAltiVec),
	    SYSTEMINFOTYPE_PPC_ALTIVEC, TAG_DONE) > 0)
		return supportsAltiVec;
# endif

	return false;
}
#endif

#ifdef OF_WINDOWS
+ (bool)isWindowsNT
{
	return !(GetVersion() & 0x80000000);
}
#endif

- (instancetype)init
{
	OF_INVALID_INIT_METHOD
}
@end