File Coverage

blib/lib/TextFileParser.pm

Criterion	Covered	Total	%
statement	75	77	97.4
branch	28	34	82.3
condition	8	12	66.6
subroutine	21	22	95.4
pod	8	8	100.0
total	140	153	91.5

use warnings;
use strict;

package TextFileParser 0.202;

# ABSTRACT: an extensible Perl class to parse any text file by specifying grammar in derived classes.

use Exporter 'import';
our (@EXPORT_OK) = ();
our (@EXPORT)    = (@EXPORT_OK);


use Exception::Class (
    'TextFileParser::Exception',
    'TextFileParser::Exception::ParsingError' => {
        isa         => 'TextFileParser::Exception',
        description => 'For all parsing errors',
        alias       => 'throw_text_parsing_error'
    },
    'TextFileParser::Exception::FileNotFound' => {
        isa         => 'TextFileParser::Exception',
        description => 'File not found',
        alias       => 'throw_file_not_found'
    },
    'TextFileParser::Exception::FileCantOpen' => {
        isa         => 'TextFileParser::Exception',
        description => 'Error opening file',
        alias       => 'throw_cant_open'
    }
);

use Try::Tiny;


sub new {
    my $pkg = shift;
    bless {}, $pkg;
}


sub read {
    my ( $self, $fname ) = @_;
    return                    if not $self->__is_file_known_or_opened($fname);
    $self->filename($fname)   if not exists $self->{__filehandle};
    delete $self->{__records} if exists $self->{__records};
    $self->__read_file_handle;
    $self->__close_file;
}

sub __is_file_known_or_opened {
    my ( $self, $fname ) = @_;
    return 0 if not defined $fname and not exists $self->{__filehandle};
    return 0 if defined $fname and not $fname;
    return 1;
}


sub filename {
    my ( $self, $fname ) = @_;
    $self->__check_and_open_file($fname) if defined $fname;
    return ( exists $self->{__filename} and defined $self->{__filename} )
        ? $self->{__filename}
        : undef;
}

sub __check_and_open_file {
    my ( $self, $fname ) = @_;
    throw_file_not_found error =>
        "No such file $fname or it has no read permissions"
        if not -f $fname or not -r $fname;
    $self->__open_file($fname);
    $self->{__filename} = $fname;
}

sub __open_file {
    my ( $self, $fname ) = @_;
    $self->__close_file if exists $self->{__filehandle};
    open my $fh, "<$fname"
        or throw_cant_open error => "Error while opening file $fname";
    $self->{__filehandle} = $fh;
    $self->{__size} = (stat $fname)[7];
}

sub __read_file_handle {
    my $self = shift;
    my $fh = $self->{__filehandle};
    $self->__init_read_fh;
    while (<$fh>) {
        $self->lines_parsed( $self->lines_parsed + 1 );
        $self->__try_to_parse($_);
    }
}

sub __init_read_fh {
    my $self = shift;
    $self->lines_parsed(0);
    $self->{__bytes_read} = 0;
}


sub lines_parsed {
    my $self = shift;
    return $self->{__current_line} = shift if @_;
    return ( exists $self->{__current_line} ) ? $self->{__current_line} : 0;
}

sub __try_to_parse {
    my ( $self, $line ) = @_;
    try { $self->save_record($line); }
    catch {
        $self->__close_file;
        $_->rethrow;
    };
}


sub save_record {
    my $self = shift;
    return if not @_;
    $self->{__records} = [] if not defined $self->{__records};
    push @{ $self->{__records} }, shift;
}

sub __close_file {
    my $self = shift;
    close $self->{__filehandle};
    delete $self->{__filehandle};
}


sub get_records {
    my $self = shift;
    return () if not exists $self->{__records};
    return @{ $self->{__records} };
}


sub last_record {
    my $self = shift;
    return undef if not exists $self->{__records};
    my (@record) = @{ $self->{__records} };
    return $record[$#record];
}


sub pop_record {
    my $self = shift;
    return undef if not exists $self->{__records};
    pop @{ $self->{__records} };
}

1;

__END__