InstallationCheck

#!/usr/bin/perl

# cribbed from the iTunes 9 installer, with some modifications

# TODO: localize (somehow)

###################################################################################################
my $SYSTEM_VERS			= "/System/Library/CoreServices/SystemVersion.plist";
my $EXIT_VALUE			= 0;
###################################################################################################

DO_CHECKS: {

	# quit with error for system earlier than 10.5
	if(CheckVersion("$SYSTEM_VERS", "10.5.0", "ProductVersion", "<")) {
			$EXIT_VALUE = ((1 << 6) | ( 1 << 5 ) | 16);
			last;
	}

	# block while the application is running
	while (CheckRunning("com.apple.Finder"))
	{
		if (DisplayAlert("Please unplug your Neat scanner before continuing.") == -1) {
			# the user cancelled
			$EXIT_VALUE = ((1 << 6) | ( 1 << 5 ) | 17);
			last;
		}
	}
	
}
exit($EXIT_VALUE);	


##################

sub CheckRunning
{
	my $bundleIdentifier = $_[0];
	my $count = `osascript -e 'tell app "System Events" to count processes whose bundle identifier is "$bundleIdentifier"' 2> /dev/null`;
	if ($count > 0)	{
		return 1;
	} else {
		return 0;
	}
}


sub DisplayAlert
{
	my $message = $_[0];

	my $script = <<"END";
tell application "Installer"
	-- activate
	try
		set dd to display dialog "$message" buttons {"Cancel", "Continue"} default button 2 with icon caution
		set response to button returned of dd
		if response = "Continue"
			return 0
		end if
	end try 
	return -1
	end tell
END

	return `osascript -e '$script'`;
}

# verbatim from iTunes 9 installer
sub CheckVersion
{
    my $path            = $_[0];
    my $version         = $_[1];
    my $keyName         = $_[2];
    my $operator        = $_[3];

    if (! -e $path) {
        return 0;
    }

    if (!$operator) {
        $operator = "==";
    }

    my $oldSeperator = $/;
    $/ = \0;

    open( PLIST, "$path") || do {
        return 0;
    };

    $plistData = <PLIST>;
    $plistData =~ /<dict>(.*?)<\/dict>/gis;

    @items = split(/<key>/, $plistData);

    shift @items;
    foreach $item (@items) {
        $item =~ /(.*?)<\/key>.*?<string>(.*?)<\/string>/gis;
        $versiondata{ $1 } = $2;
    }

    close(PLIST);

    $/ = $oldSeperator;

    @theVersionArray = split(/\./, $versiondata{$keyName});
    for ($i = 0; $i < 3; $i++) {
        if(!$theVersionArray[$i]) {
            $theVersionArray[$i] = '0';
        }
    }

    @versionArray = split(/\./, $version);
    
    my $actualVersion;

    for ($i = 0; $i < 3; $i++) {
        if (($theVersionArray[$i] != $versionArray[$i]) or ($i == 2)) {

            $actualVersion = $theVersionArray[$i];
            $version = $versionArray[$i];

            last;
        }
    }

    my $expression = '$actualVersion ' . $operator . ' $version';
    if( eval ($expression) )
    {
        return 1;
    }
    else
    {
        return 0;
    }

}