/*
 * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017
 *   Jonathan Schleifer <js@heap.zone>
 *
 * 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.
 */

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <errno.h>
#include <signal.h>

#include "unistd_wrapper.h"

#import "OFApplication.h"
#import "OFString.h"
#import "OFArray.h"
#import "OFDictionary.h"
#import "OFLocalization.h"
#import "OFRunLoop.h"
#import "OFRunLoop+Private.h"
#import "OFThread.h"
#import "OFThread+Private.h"
#import "OFSandbox.h"
#ifdef OF_MORPHOS
# import "OFFile.h"
# import "OFFileManager.h"
#endif

#import "OFOutOfMemoryException.h"
#import "OFOutOfRangeException.h"
#import "OFSandboxActivationFailedException.h"

#if defined(OF_MACOS)
# include <crt_externs.h>
#elif defined(OF_WINDOWS)
# include <windows.h>

extern int _CRT_glob;
extern void __wgetmainargs(int *, wchar_t ***, wchar_t ***, int, int *);
#elif defined(OF_MORPHOS)
# define BOOL EXEC_BOOL
# include <proto/exec.h>
# include <proto/dos.h>
# undef BOOL
#elif !defined(OF_IOS)
extern char **environ;
#endif

#ifdef OF_PSP
# include <pspkerneltypes.h>
# include <psploadexec.h>
#endif

#ifdef OF_NINTENDO_DS
# define asm __asm__
# include <nds.h>
# undef asm
#endif

@interface OFApplication ()
- (instancetype)of_init OF_METHOD_FAMILY(init);
- (void)of_setArgumentCount: (int *)argc
	  andArgumentValues: (char **[])argv;
#ifdef OF_WINDOWS
- (void)of_setArgumentCount: (int)argc
      andWideArgumentValues: (wchar_t *[])argv;
#endif
- (void)of_run;
@end

static OFApplication *app = nil;

static void
atexitHandler(void)
{
	id <OFApplicationDelegate> delegate = [app delegate];

	if ([delegate respondsToSelector: @selector(applicationWillTerminate)])
		[delegate applicationWillTerminate];

	[delegate release];
}

#define SIGNAL_HANDLER(signal)					\
	static void						\
	handle##signal(int sig)					\
	{							\
		app->_##signal##Handler(app->_delegate,		\
		    @selector(applicationDidReceive##signal));	\
	}
SIGNAL_HANDLER(SIGINT)
#ifdef SIGHUP
SIGNAL_HANDLER(SIGHUP)
#endif
#ifdef SIGUSR1
SIGNAL_HANDLER(SIGUSR1)
#endif
#ifdef SIGUSR2
SIGNAL_HANDLER(SIGUSR2)
#endif
#undef SIGNAL_HANDLER

int
of_application_main(int *argc, char **argv[], Class cls)
{
	id <OFApplicationDelegate> delegate;
#ifdef OF_WINDOWS
	wchar_t **wargv, **wenvp;
	int wargc, si = 0;
#endif

	[[OFLocalization alloc] init];

	if (![cls conformsToProtocol: @protocol(OFApplicationDelegate)]) {
		fprintf(stderr, "FATAL ERROR:\n  Class %s does not conform to "
		    "protocol OFApplicationDelegate,\n  but was specified via "
		    "OF_APPLICATION_DELEGATE()!\n", class_getName(cls));
		exit(1);
	}

	app = [[OFApplication alloc] of_init];

	[app of_setArgumentCount: argc
	       andArgumentValues: argv];

#ifdef OF_WINDOWS
	__wgetmainargs(&wargc, &wargv, &wenvp, _CRT_glob, &si);
	[app of_setArgumentCount: wargc
	   andWideArgumentValues: wargv];
#endif

	delegate = [[cls alloc] init];
	[app setDelegate: delegate];

	[app of_run];

	[delegate release];

	return 0;
}

@implementation OFApplication
@synthesize programName = _programName, arguments = _arguments;
@synthesize environment = _environment;

+ (OFApplication *)sharedApplication
{
	return app;
}

+ (OFString *)programName
{
	return [app programName];
}

+ (OFArray *)arguments
{
	return [app arguments];
}

+ (OFDictionary *)environment
{
	return [app environment];
}

+ (void)terminate
{
	[self terminateWithStatus: EXIT_SUCCESS];

	OF_UNREACHABLE
}

+ (void)terminateWithStatus: (int)status
{
#ifndef OF_PSP
	exit(status);
#else
	sceKernelExitGame();

	OF_UNREACHABLE
#endif
}

#ifdef OF_HAVE_SANDBOX
+ (void)activateSandbox: (OFSandbox *)sandbox
{
	[app activateSandbox: sandbox];
}
#endif

- (instancetype)init
{
	OF_INVALID_INIT_METHOD
}

- (instancetype)of_init
{
	self = [super init];

	@try {
		_environment = [[OFMutableDictionary alloc] init];

		atexit(atexitHandler);

#if defined(OF_WINDOWS)
		char16_t *env, *env0;
		env = env0 = GetEnvironmentStringsW();

		while (*env != 0) {
			void *pool = objc_autoreleasePoolPush();
			OFString *tmp, *key, *value;
			size_t length, pos;

			length = of_string_utf16_length(env);
			tmp = [OFString stringWithUTF16String: env
						       length: length];
			env += length + 1;

			/*
			 * cmd.exe seems to add some special variables which
			 * start with a "=", even though variable names are not
			 * allowed to contain a "=".
			 */
			if ([tmp hasPrefix: @"="]) {
				objc_autoreleasePoolPop(pool);
				continue;
			}

			pos = [tmp rangeOfString: @"="].location;
			if (pos == OF_NOT_FOUND) {
				fprintf(stderr, "Warning: Invalid environment "
				    "variable: %s\n", [tmp UTF8String]);
				continue;
			}

			key = [tmp substringWithRange: of_range(0, pos)];
			value = [tmp substringWithRange:
			    of_range(pos + 1, [tmp length] - pos - 1)];

			[_environment setObject: value
					 forKey: key];

			objc_autoreleasePoolPop(pool);
		}

		FreeEnvironmentStringsW(env0);
#elif defined(OF_MORPHOS)
		void *pool = objc_autoreleasePoolPush();
		OFFileManager *fileManager = [OFFileManager defaultManager];
		OFArray *envContents =
		    [fileManager contentsOfDirectoryAtPath: @"ENV:"];
		const of_string_encoding_t encoding = [OFLocalization encoding];
		struct Process *proc;
		struct LocalVar *firstLocalVar;

		for (OFString *name in envContents) {
			void *pool2 = objc_autoreleasePoolPush();
			OFString *path, *value;
			OFFile *file;

			if ([name containsString: @"."])
				continue;

			path = [@"ENV:" stringByAppendingString: name];

			if ([fileManager directoryExistsAtPath: path])
				continue;

			file = [OFFile fileWithPath: path
					       mode: @"r"];

			value = [file readLineWithEncoding: encoding];
			if (value != nil)
				[_environment setObject: value
						 forKey: name];

			objc_autoreleasePoolPop(pool2);
		}

		/* Local variables override global variables */
		proc = (struct Process *)FindTask(NULL);
		firstLocalVar = (struct LocalVar *)proc->pr_LocalVars.mlh_Head;

		for (struct LocalVar *iter = firstLocalVar;
		    iter->lv_Node.ln_Succ != NULL;
		    iter = (struct LocalVar *)iter->lv_Node.ln_Succ) {
			size_t length;
			OFString *key, *value;

			if (iter->lv_Node.ln_Type != LV_VAR ||
			    iter->lv_Flags & GVF_BINARY_VAR)
				continue;

			for (length = 0; length < iter->lv_Len; length++)
				if (iter->lv_Value[length] == 0)
					break;

			key = [OFString stringWithCString: iter->lv_Node.ln_Name
						 encoding: encoding];
			value = [OFString
			    stringWithCString: (const char *)iter->lv_Value
				     encoding: encoding
				       length: length];

			[_environment setObject: value
					 forKey: key];
		}

		objc_autoreleasePoolPop(pool);
#elif !defined(OF_IOS)
# ifndef OF_MACOS
		char **env = environ;
# else
		char **env = *_NSGetEnviron();
# endif

		if (env != NULL) {
			const of_string_encoding_t encoding =
			    [OFLocalization encoding];

			for (; *env != NULL; env++) {
				void *pool = objc_autoreleasePoolPush();
				OFString *key, *value;
				char *sep;

				if ((sep = strchr(*env, '=')) == NULL) {
					fprintf(stderr, "Warning: Invalid "
					    "environment variable: %s\n", *env);
					continue;
				}

				key = [OFString
				    stringWithCString: *env
					     encoding: encoding
					       length: sep - *env];
				value = [OFString
				    stringWithCString: sep + 1
					     encoding: encoding];

				[_environment setObject: value
						 forKey: key];

				objc_autoreleasePoolPop(pool);
			}
		}
#else
		/*
		 * iOS does not provide environ and Apple does not allow using
		 * _NSGetEnviron on iOS. Therefore, we just get a few common
		 * variables from the environment which applications might
		 * expect.
		 */

		void *pool = objc_autoreleasePoolPush();
		char *env;

		if ((env = getenv("HOME")) != NULL) {
			OFString *home = [[[OFString alloc]
			    initWithUTF8StringNoCopy: env
					freeWhenDone: false] autorelease];
			[_environment setObject: home
					 forKey: @"HOME"];
		}
		if ((env = getenv("PATH")) != NULL) {
			OFString *path = [[[OFString alloc]
			    initWithUTF8StringNoCopy: env
					freeWhenDone: false] autorelease];
			[_environment setObject: path
					 forKey: @"PATH"];
		}
		if ((env = getenv("SHELL")) != NULL) {
			OFString *shell = [[[OFString alloc]
			    initWithUTF8StringNoCopy: env
					freeWhenDone: false] autorelease];
			[_environment setObject: shell
					 forKey: @"SHELL"];
		}
		if ((env = getenv("TMPDIR")) != NULL) {
			OFString *tmpdir = [[[OFString alloc]
			    initWithUTF8StringNoCopy: env
					freeWhenDone: false] autorelease];
			[_environment setObject: tmpdir
					 forKey: @"TMPDIR"];
		}
		if ((env = getenv("USER")) != NULL) {
			OFString *user = [[[OFString alloc]
			    initWithUTF8StringNoCopy: env
					freeWhenDone: false] autorelease];
			[_environment setObject: user
					 forKey: @"USER"];
		}

		objc_autoreleasePoolPop(pool);
#endif

		[_environment makeImmutable];
	} @catch (id e) {
		[self release];
		@throw e;
	}

	return self;
}

- (void)dealloc
{
	[_arguments release];
	[_environment release];

	[super dealloc];
}

- (void)of_setArgumentCount: (int *)argc
	  andArgumentValues: (char ***)argv
{
#ifndef OF_WINDOWS
	void *pool = objc_autoreleasePoolPush();
	OFMutableArray *arguments;
	of_string_encoding_t encoding;

	_argc = argc;
	_argv = argv;

	encoding = [OFLocalization encoding];

# ifndef OF_NINTENDO_DS
	if (*argc > 0) {
# else
	if (__system_argv->argvMagic == ARGV_MAGIC &&
	    __system_argv->argc > 0) {
# endif
		_programName = [[OFString alloc] initWithCString: (*argv)[0]
							encoding: encoding];
		arguments = [[OFMutableArray alloc] init];
		_arguments = arguments;

		for (int i = 1; i < *argc; i++)
			[arguments addObject:
			    [OFString stringWithCString: (*argv)[i]
					       encoding: encoding]];

		[arguments makeImmutable];
	}

	objc_autoreleasePoolPop(pool);
#else
	_argc = argc;
	_argv = argv;
#endif
}

#ifdef OF_WINDOWS
- (void)of_setArgumentCount: (int)argc
      andWideArgumentValues: (wchar_t **)argv
{
	void *pool = objc_autoreleasePoolPush();
	OFMutableArray *arguments;

	if (argc > 0) {
		_programName = [[OFString alloc] initWithUTF16String: argv[0]];
		arguments = [[OFMutableArray alloc] init];

		for (int i = 1; i < argc; i++)
			[arguments addObject:
			    [OFString stringWithUTF16String: argv[i]]];

		[arguments makeImmutable];
		_arguments = arguments;
	}

	objc_autoreleasePoolPop(pool);
}
#endif

- (void)getArgumentCount: (int **)argc
       andArgumentValues: (char ****)argv
{
	*argc = _argc;
	*argv = _argv;
}

- (id <OFApplicationDelegate>)delegate
{
	return _delegate;
}

- (void)setDelegate: (id <OFApplicationDelegate>)delegate
{
#define REGISTER_SIGNAL(sig)						\
	if ([delegate respondsToSelector:				\
	    @selector(applicationDidReceive##sig)]) {			\
		_##sig##Handler = (void (*)(id, SEL))[(id)delegate	\
		    methodForSelector:					\
		    @selector(applicationDidReceive##sig)];		\
		signal(sig, handle##sig);				\
	} else {							\
		_##sig##Handler = NULL;					\
		signal(sig, (void (*)(int))SIG_DFL);			\
	}

	_delegate = delegate;

	REGISTER_SIGNAL(SIGINT)
#ifdef SIGHUP
	REGISTER_SIGNAL(SIGHUP)
#endif
#ifdef SIGUSR1
	REGISTER_SIGNAL(SIGUSR1)
#endif
#ifdef SIGUSR2
	REGISTER_SIGNAL(SIGUSR2)
#endif

#undef REGISTER_SIGNAL
}

- (void)of_run
{
	void *pool = objc_autoreleasePoolPush();
	OFRunLoop *runLoop;

#ifdef OF_HAVE_THREADS
	[OFThread of_createMainThread];
	runLoop = [OFRunLoop currentRunLoop];
#else
	runLoop = [[[OFRunLoop alloc] init] autorelease];
#endif

	[OFRunLoop of_setMainRunLoop: runLoop];

	objc_autoreleasePoolPop(pool);

	/*
	 * Note: runLoop is still valid after the release of the pool, as
	 * of_setMainRunLoop: retained it. However, we only have a weak
	 * reference to it now, whereas we had a strong reference before.
	 */

	pool = objc_autoreleasePoolPush();
	[_delegate applicationDidFinishLaunching];
	objc_autoreleasePoolPop(pool);

	[runLoop run];
}

- (void)terminate
{
	[[self class] terminate];

	OF_UNREACHABLE
}

- (void)terminateWithStatus: (int)status
{
	[[self class] terminateWithStatus: status];

	OF_UNREACHABLE
}

#ifdef OF_HAVE_SANDBOX
- (void)activateSandbox: (OFSandbox *)sandbox
{
# ifdef OF_HAVE_PLEDGE
	void *pool = objc_autoreleasePoolPush();
	const char *promises = [[sandbox pledgeString]
	    cStringWithEncoding: [OFLocalization encoding]];

	if (pledge(promises, NULL) != 0)
		@throw [OFSandboxActivationFailedException
		    exceptionWithSandbox: sandbox
				   errNo: errno];

	objc_autoreleasePoolPop(pool);
# endif
}
#endif
@end