package My::parser::file;
use strict;
use warnings;
use File::Tail 0.91;


sub new {
	my $class	= shift;
	my $config	= shift;
	my $rest	= shift;
	return \$class if($rest);
	my $self	= {};
	bless ($self, $class);
	$self->{'config'}	= $config;
	$self->{'config'}->{'fetcher'}->{'file'}	= $self;
	return $self;
}

sub init {
	my $self	= shift;
	my $parser	= shift;
	if($parser) {
		my $hash	= $self->{'config'}->get_parser_info($parser);
		if($hash->{'type'} eq 'file') {
			my %opts		= %{ &set_defaults };
			my $filename		= $hash->{'source'};
			my $maxinterval		= $self->{'config'}->get_as_single_val('config','maxinterval');
			my $interval		= $self->{'config'}->get_as_single_val('config','interval');
			my $adjustafter		= $self->{'config'}->get_as_single_val('config','adjustafter');
			my $resetafter		= $self->{'config'}->get_as_single_val('config','resetafter');
			my $maxbuf		= $self->{'config'}->get_as_single_val('config','maxbuf');
			my $nowait		= $self->{'config'}->get_as_single_val('config','nowait');
			my $ignore_nonexistant	= $self->{'config'}->get_as_single_val('config','ignore_nonexistant');
			my $tail		= $self->{'config'}->get_as_single_val('config','tail');
			my $reset_tail		= $self->{'config'}->get_as_single_val('config','reset_tail');
			$opts{'name'}		= $filename;
			$opts{'maxinterval'}	= $maxinterval	if(defined($maxinterval));
			$opts{'interval'}	= $interval	if(defined($interval));
			$opts{'adjustafter'}	= $adjustafter	if(defined($adjustafter));
			$opts{'resetafter'}	= $resetafter	if(defined($resetafter));
			$opts{'maxbuf'}		= $maxbuf	if(defined($maxbuf));
			$opts{'nowait'}		= $nowait	if(defined($nowait));
			$opts{'ignore_nonexistant'}	= $ignore_nonexistant	if(defined($ignore_nonexistant));
			$opts{'tail'}		= $tail		if(defined($tail));
			$opts{'reset_tail'}	= $reset_tail	if(defined($reset_tail));
			$self->{'config'}->{'logger'}->log("Initializing fetcher file from parser $parser with file $filename");
			my $newfetcher	= File::Tail->new(%opts);
			$self->{'config'}->set_fetcher('file',$parser,$newfetcher);
			return 1;
		} else {
			return 0;
		}
	} else {
		return 0;
	}
}

sub set_defaults {
	my $opts;
	$opts->{'maxinterval'}		= 60; #max time spent sleeping between checks
	$opts->{'interval'}		= 10; #initial time before first check
	$opts->{'adjustafter'}		= 10; #number of times $interval passes before adjusting the check interval
	$opts->{'resetafter'}		= $opts->{'interval'} * $opts->{'adjustafter'}; #Number of seconds after last change to file before reopening the file
	$opts->{'maxbuf'}		= 16384;
	$opts->{'nowait'}		= 0; #Does not block on read, but returns an empty string if there is nothing to read.
	$opts->{'ignore_nonexistant'}	= 0; #Do not complain if the file doesn't exist when it is first opened or when it is to be reopened.
	$opts->{'tail'}			= 0; #When first started, read and return C<n> lines from the file. If C<n> is zero, start at the end of file. If C<n> is negative, return the whole file.
	$opts->{'reset_tail'}		= 0; #Same as tail, but for when $resetafter has gone by without any changes to the file
	return $opts;
}

1;