//
//  PFMoveApplication.m, version 1.2
//  LetsMove
//
//  Created by Andy Kim at Potion Factory LLC on 9/17/09
//
//  The contents of this file are dedicated to the public domain.
//
//  Contributors:
//	  Andy Kim
//    John Brayton
//    Chad Sellers
//    Kevin LaCoste
//    Rasmus Andersson / Spotify
//

#import "PFMoveApplication.h"
#import <Security/Security.h>

// Strings
// These are macros to be able to use custom i18n tools
#define _I10NS(nsstr) NSLocalizedStringFromTable(nsstr, @"MoveApplication", nil)
#define kStrMoveApplicationCouldNotMove _I10NS(@"Could not move to Applications folder")
#define kStrMoveApplicationQuestionTitle  _I10NS(@"Move to Applications folder?")
#define kStrMoveApplicationQuestionTitleHome _I10NS(@"Move to Applications folder in your Home folder?")
#define kStrMoveApplicationQuestionMessage _I10NS(@"I can move myself to the Applications folder if you'd like.")
#define kStrMoveApplicationButtonMove _I10NS(@"Move to Applications Folder")
#define kStrMoveApplicationButtonDoNotMove _I10NS(@"Do Not Move")
#define kStrMoveApplicationQuestionInfoWillRequirePasswd _I10NS(@"Note that this will require an administrator password.")
#define kStrMoveApplicationQuestionInfoInDownloadsFolder _I10NS(@"This will keep your Downloads folder uncluttered.")

// Need to be defined
#ifndef NSAppKitVersionNumber10_4
	#define NSAppKitVersionNumber10_4 824
#endif

static NSString *AlertSuppressKey = @"moveToApplicationsFolderAlertSuppress";


// Helper functions
static NSString *PreferredInstallLocation(BOOL *isUserDirectory);
static BOOL IsInApplicationsFolder(NSString *path);
static BOOL IsInDownloadsFolder(NSString *path);
static BOOL Trash(NSString *path);
static BOOL AuthorizedInstall(NSString *srcPath, NSString *dstPath, BOOL *canceled);
static BOOL CopyBundle(NSString *srcPath, NSString *dstPath);


// Main worker function
void PFMoveToApplicationsFolderIfNecessary()
{
	// Skip if user suppressed the alert before
	if ([[NSUserDefaults standardUserDefaults] boolForKey:AlertSuppressKey]) return;

	// Path of the bundle
	NSString *bundlePath = [[NSBundle mainBundle] bundlePath];

	// Skip if the application is already in some Applications folder
	if (IsInApplicationsFolder(bundlePath)) return;

	// File Manager
	NSFileManager *fm = [NSFileManager defaultManager];
	BOOL bundlePathIsWritable = [fm isWritableFileAtPath:bundlePath];

	// Guess if we have launched from a disk image
	BOOL isLaunchedFromDMG = ([bundlePath hasPrefix:@"/Volumes/"] && !bundlePathIsWritable);

	// Fail silently if there's no access to delete the original application
	if (!isLaunchedFromDMG && !bundlePathIsWritable) {
		NSLog(@"INFO -- No access to delete the app. Not offering to move it.");
		return;
	}

	// Since we are good to go, get the preferred installation directory.
	BOOL installToUserApplications = NO;
	NSString *applicationsDirectory = PreferredInstallLocation(&installToUserApplications);
	NSString *bundleName = [bundlePath lastPathComponent];
	NSString *destinationPath = [applicationsDirectory stringByAppendingPathComponent:bundleName];

	// Check if we need admin password to write to the Applications directory
	BOOL needAuthorization = ([fm isWritableFileAtPath:applicationsDirectory] == NO);

	// Setup the alert
	NSAlert *alert = [[[NSAlert alloc] init] autorelease];
	{
		NSString *informativeText = nil;

		[alert setMessageText:(installToUserApplications ? kStrMoveApplicationQuestionTitleHome : kStrMoveApplicationQuestionTitle)];

		informativeText = kStrMoveApplicationQuestionMessage;

		if (needAuthorization) {
			informativeText = [informativeText stringByAppendingString:@" "];
			informativeText = [informativeText stringByAppendingString:kStrMoveApplicationQuestionInfoWillRequirePasswd];
		}
		else if (IsInDownloadsFolder(bundlePath)) {
			// Don't mention this stuff if we need authentication. The informative text is long enough as it is in that case.
			informativeText = [informativeText stringByAppendingString:@" "];
			informativeText = [informativeText stringByAppendingString:kStrMoveApplicationQuestionInfoInDownloadsFolder];
		}

		[alert setInformativeText:informativeText];

		// Add accept button
		[alert addButtonWithTitle:kStrMoveApplicationButtonMove];

		// Add deny button
		NSButton *cancelButton = [alert addButtonWithTitle:kStrMoveApplicationButtonDoNotMove];
		[cancelButton setKeyEquivalent:@"\e"];

#if MAC_OS_X_VERSION_MAX_ALLOWED > MAC_OS_X_VERSION_10_4
		if (floor(NSAppKitVersionNumber) > NSAppKitVersionNumber10_4) {
			// Setup suppression button
			[alert setShowsSuppressionButton:YES];
			[[[alert suppressionButton] cell] setControlSize:NSSmallControlSize];
			[[[alert suppressionButton] cell] setFont:[NSFont systemFontOfSize:[NSFont smallSystemFontSize]]];
		}
#endif
	}

	if ([alert runModal] == NSAlertFirstButtonReturn) {
		NSLog(@"INFO -- Moving myself to the Applications folder");

		// Move
		if (needAuthorization) {
			BOOL authorizationCanceled;

			if (!AuthorizedInstall(bundlePath, destinationPath, &authorizationCanceled)) {
				if (authorizationCanceled) {
					NSLog(@"INFO -- Not moving because user canceled authorization");
					return;
				}
				else {
					NSLog(@"ERROR -- Could not copy myself to /Applications with authorization");
					goto fail;
				}
			}
		}
		else {
			// If a copy already exists in the Applications folder, put it in the Trash
			if ([fm fileExistsAtPath:destinationPath]) {
				// If the app at destinationPath is running already, give that app focus and exit.
				NSString *script = [NSString stringWithFormat:@"ps xa -o pid,comm | grep '%@/' | grep -v grep | cut -d' ' -f1 | grep -v '^%d$' >/dev/null", destinationPath, getpid()];
				NSTask *ps = [NSTask launchedTaskWithLaunchPath:@"/bin/sh" arguments:[NSArray arrayWithObjects:@"-c", script, nil]];
				[ps waitUntilExit];

				if ([ps terminationStatus] == 0) {
					NSLog(@"INFO -- Switching to an already running version");
					[[NSTask launchedTaskWithLaunchPath:@"/usr/bin/open" arguments:[NSArray arrayWithObject:destinationPath]] waitUntilExit];
					[NSApp terminate:nil];
				}

				if (!Trash([applicationsDirectory stringByAppendingPathComponent:bundleName]))
					goto fail;
			}

 			if (!CopyBundle(bundlePath, destinationPath)) {
				NSLog(@"ERROR -- Could not copy myself to /Applications");
				goto fail;
			}
		}

		// Trash the original app. It's okay if this fails.
		// NOTE: This final delete does not work if the source bundle is in a network mounted volume.
		//       Calling rm or file manager's delete method doesn't work either. It's unlikely to happen
		//       but it'd be great if someone could fix this.
		if (!isLaunchedFromDMG && !Trash(bundlePath)) {
			NSLog(@"WARNING -- Could not delete application after moving it to Applications folder");
		}

		// Relaunch.
		// The shell script waits until the original app process terminates.
		// This is done so that the relaunched app opens as the front-most app.
		int pid = [[NSProcessInfo processInfo] processIdentifier];
		NSString *script = [NSString stringWithFormat:@"while [ `ps -p %d | wc -l` -gt 1 ]; do sleep 0.1; done; open '%@'", pid, destinationPath];
		[NSTask launchedTaskWithLaunchPath:@"/bin/sh" arguments:[NSArray arrayWithObjects:@"-c", script, nil]];

		// Launched from within a DMG? -- unmount (if no files are open after 5 seconds,
		// otherwise leave it mounted).
		if (isLaunchedFromDMG) {
			NSString *script = [NSString stringWithFormat:@"(sleep 5 && hdiutil detach '%@') &", [bundlePath stringByDeletingLastPathComponent]];
			[NSTask launchedTaskWithLaunchPath:@"/bin/sh" arguments:[NSArray arrayWithObjects:@"-c", script, nil]];
		}

		[NSApp terminate:nil];
	}
	else {
		if (floor(NSAppKitVersionNumber) > NSAppKitVersionNumber10_4) {
			// Save the alert suppress preference if checked
#if MAC_OS_X_VERSION_MAX_ALLOWED > MAC_OS_X_VERSION_10_4
			if ([[alert suppressionButton] state] == NSOnState) {
				[[NSUserDefaults standardUserDefaults] setBool:YES forKey:AlertSuppressKey];
			}
#endif
		}
		else {
			// Always suppress after the first decline on 10.4 since there is no suppression checkbox
			[[NSUserDefaults standardUserDefaults] setBool:YES forKey:AlertSuppressKey];
		}
	}

	return;

fail:
	{
		// Show failure message
		NSAlert *alert = [[[NSAlert alloc] init] autorelease];
		[alert setMessageText:kStrMoveApplicationCouldNotMove];
		[alert runModal];
	}
}

#pragma mark -
#pragma mark Helper Functions

static NSString *PreferredInstallLocation(BOOL *isUserDirectory)
{
	// Return the preferred install location.
	// Assume that if the user has a ~/Applications folder, they'd prefer their
	// applications to go there.

	NSFileManager *fm = [NSFileManager defaultManager];

	NSArray *userApplicationsDirs = NSSearchPathForDirectoriesInDomains(NSApplicationDirectory, NSUserDomainMask, YES);

	if ([userApplicationsDirs count] > 0) {
		NSString *userApplicationsDir = [userApplicationsDirs objectAtIndex:0];
		BOOL isDirectory;

		if ([fm fileExistsAtPath:userApplicationsDir isDirectory:&isDirectory] && isDirectory) {
			if (isUserDirectory) *isUserDirectory = YES;
			return userApplicationsDir;
		}
	}

	// No user Applications directory. Return the machine local Applications directory
	if (isUserDirectory) *isUserDirectory = NO;
	return [NSSearchPathForDirectoriesInDomains(NSApplicationDirectory, NSLocalDomainMask, YES) lastObject];
}

static BOOL IsInApplicationsFolder(NSString *path)
{
	NSEnumerator *e = [NSSearchPathForDirectoriesInDomains(NSApplicationDirectory, NSAllDomainsMask, YES) objectEnumerator];
	NSString *appDirPath = nil;

	while ((appDirPath = [e nextObject])) {
		if ([path hasPrefix:appDirPath]) return YES;
	}

	return NO;
}

static BOOL IsInDownloadsFolder(NSString *path)
{
#if MAC_OS_X_VERSION_MAX_ALLOWED > MAC_OS_X_VERSION_10_4
	// 10.5 or higher has NSDownloadsDirectory
	if (floor(NSAppKitVersionNumber) > NSAppKitVersionNumber10_4) {
		NSEnumerator *e = [NSSearchPathForDirectoriesInDomains(NSDownloadsDirectory, NSAllDomainsMask, YES) objectEnumerator];
		NSString *downloadsDirPath = nil;

		while ((downloadsDirPath = [e nextObject])) {
			if ([path hasPrefix:downloadsDirPath]) return YES;
		}

		return NO;
	}
#endif
	// 10.4
	return [[[path stringByDeletingLastPathComponent] lastPathComponent] isEqualToString:@"Downloads"];
}

static BOOL Trash(NSString *path)
{
	if ([[NSWorkspace sharedWorkspace] performFileOperation:NSWorkspaceRecycleOperation
													 source:[path stringByDeletingLastPathComponent]
												destination:@""
													  files:[NSArray arrayWithObject:[path lastPathComponent]]
														tag:NULL]) {
		return YES;
	}
	else {
		NSLog(@"ERROR -- Could not trash '%@'", path);
		return NO;
	}
}

static BOOL AuthorizedInstall(NSString *srcPath, NSString *dstPath, BOOL *canceled)
{
	if (canceled) *canceled = NO;

	// Make sure that the destination path is an app bundle. We're essentially running 'sudo rm -rf'
	// so we really don't want to fuck this up.
	if (![dstPath hasSuffix:@".app"]) return NO;

	// Do some more checks
	if ([[dstPath stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]] length] == 0) return NO;
	if ([[srcPath stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]] length] == 0) return NO;

	int pid, status;
	AuthorizationRef myAuthorizationRef;

	// Get the authorization
	OSStatus err = AuthorizationCreate(NULL, kAuthorizationEmptyEnvironment, kAuthorizationFlagDefaults, &myAuthorizationRef);
	if (err != errAuthorizationSuccess) return NO;

	AuthorizationItem myItems = {kAuthorizationRightExecute, 0, NULL, 0};
	AuthorizationRights myRights = {1, &myItems};
	AuthorizationFlags myFlags = kAuthorizationFlagInteractionAllowed | kAuthorizationFlagPreAuthorize | kAuthorizationFlagExtendRights;

	err = AuthorizationCopyRights(myAuthorizationRef, &myRights, NULL, myFlags, NULL);
	if (err != errAuthorizationSuccess) {
		if (err == errAuthorizationCanceled && canceled)
			*canceled = YES;
		goto fail;
	}

	// Delete the destination
	{
		char *args[] = {"-rf", (char *)[dstPath UTF8String], NULL};
		err = AuthorizationExecuteWithPrivileges(myAuthorizationRef, "/bin/rm", kAuthorizationFlagDefaults, args, NULL);
		if (err != errAuthorizationSuccess) goto fail;

		// Wait until it's done
		pid = wait(&status);
		if (pid == -1 || !WIFEXITED(status)) goto fail; // We don't care about exit status as the destination most likely does not exist
	}

	// Copy
	{
		char *args[] = {"-pR", (char *)[srcPath UTF8String], (char *)[dstPath UTF8String], NULL};
		err = AuthorizationExecuteWithPrivileges(myAuthorizationRef, "/bin/cp", kAuthorizationFlagDefaults, args, NULL);
		if (err != errAuthorizationSuccess) goto fail;

		// Wait until it's done
		pid = wait(&status);
		if (pid == -1 || !WIFEXITED(status) || WEXITSTATUS(status)) goto fail;
	}

	AuthorizationFree(myAuthorizationRef, kAuthorizationFlagDefaults);
	return YES;

fail:
	AuthorizationFree(myAuthorizationRef, kAuthorizationFlagDefaults);
	return NO;
}

static BOOL CopyBundle(NSString *srcPath, NSString *dstPath)
{
	NSFileManager *fm = [NSFileManager defaultManager];

#if MAC_OS_X_VERSION_MAX_ALLOWED > MAC_OS_X_VERSION_10_4
	// 10.5 or higher
	if (floor(NSAppKitVersionNumber) > NSAppKitVersionNumber10_4) {
		NSError *error = nil;
		if (![fm copyItemAtPath:srcPath toPath:dstPath error:&error]) {
			NSLog(@"ERROR -- Could not copy '%@' to '%@' (%@)", srcPath, dstPath, error);
			return NO;
		}
		return YES;
	}
#endif
#if MAC_OS_X_VERSION_MIN_REQUIRED <= MAC_OS_X_VERSION_10_4
	// 10.4. Welcome to the whack a deprecation warning show
	BOOL success = NO;
	SEL selector = @selector(copyPath:toPath:handler:);
	NSMethodSignature *methodSig = [fm methodSignatureForSelector:selector];
	NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:methodSig];
	id nilPointer = nil;
	[invocation setSelector:selector];
	[invocation setArgument:&srcPath atIndex:2];
	[invocation setArgument:&dstPath atIndex:3];
	[invocation setArgument:&nilPointer atIndex:4];
	[invocation invokeWithTarget:fm];
	[invocation getReturnValue:&success];

	if (!success) {
		NSLog(@"ERROR -- Could not copy '%@' to '%@'", srcPath, dstPath);
	}

	return success;
#else
	return NO;
#endif
}