package Catmandu::Interactive;

use Catmandu::Sane;

our $VERSION = '0.9504';

use Catmandu;
use Moo;
use namespace::clean;

has in => (is => 'ro' , default => sub {
    Catmandu::Util::io(\*STDIN);
});

has out => (is => 'ro' , default => sub { 
    Catmandu::Util::io(\*STDOUT, mode => 'w', binmode => ':encoding(utf-8)');
});

has silent => (is => 'ro');

has exporter => (is => 'ro' , default => sub { 'YAML'} );

has exporter_args => (is => 'ro' , default => sub { +{} });

has header => (is => 'ro' , default => sub {
    "\e[36m\n" .
    "      A_A    ____      _                             _             \n" .
    "     (-.-)  / ___|__ _| |_ _ __ ___   __ _ _ __   __| |_   _       \n" .
    "      |-|  | |   / _` | __| '_ ` _ \\ / _` | '_ \\ / _` | | | |    \n" .
    "     /   \\ | |__| (_| | |_| | | | | | (_| | | | | (_| | |_| |     \n" .
    "    |     | \\____\\__,_|\\__|_| |_| |_|\\__,_|_| |_|\\__,_|\\__,_|\n" .
    "    |  || |  |  \\___            version: $Catmandu::VERSION       \n" .
    "     \\_||_/_/                                                \e[0m\n" .
    "                                                                   \n" .
    "Commands:                     | Interactive support is still       \n" .
    " \\h - the fix history         | experimental. Run:                \n" .
    " \\r - repeat the previous fix | \$ catmandu run <your_fix_script> \n" .
    " \\q - quit                    | to access all Catmandu features   \n";
});

has data => (is => 'rw' , default => sub { + {} });

has _history => (is => 'ro' , default => sub { [] });

sub run {
    my $self = shift;

    my $keep_reading = 0;
    my $buffer = '';

    $self->head;

    $self->prompt;

    while (my $line = $self->in->getline) {
        if ($line =~ /^\\(.*)/) {
            next if length $buffer;

            my ($command,$args) = split(/\s+/,$1,2);
            
            if ($command eq 'h') {
                $self->cmd_history;
                $self->prompt('fix');
                next;
            }
            elsif ($command eq 'r') {
                if (@{$self->_history} > 0) {
                    $line = $self->_history->[-1];
                } else {
                    $self->prompt('fix');
                    next;
                }
            }
            elsif ($command eq 'q') {
                last;
            }
            else {
                $self->error("unknown command $command");
                $self->prompt('fix');
                next;
            }
        }

        $line = "$buffer$line" if length $buffer;

        if (length $line) {
            my ($fixes,$keep_reading,$error) = $self->parse_fixes($line,$keep_reading);

            if ($error) {
                $buffer = '';
            }
            elsif ($keep_reading == 0) {
                my $fixer = Catmandu::Fix->new(fixes => $fixes);
                
                $self->data( $fixer->fix($self->data) );
                $self->export;

                push(@{$self->_history},$line);

                $buffer = '';
            }
            else {
                $buffer = $line;
                $self->prompt('...');
                next;
            }
        }

        $self->prompt('fix');
    }
}

sub cmd_history {
    my ($self) = @_;

    $self->out->printf(join("",@{$self->_history}));
}

sub head {
    my ($self) = @_;

    $self->out->printf("%s\n" , $self->header) unless $self->silent;
}

sub error {
    my ($self,$txt) = @_;
    $self->out->print("ERROR: $txt\n") unless $self->silent;
}

sub prompt {
    my ($self,$txt) = @_;
    $txt //= 'fix';

    $self->out->printf("\e[35m%s > \e[0m" , $txt) unless $self->silent;
}

sub export {
    my ($self) = @_;
    my $exporter = Catmandu->exporter(
                        $self->exporter, %{$self->exporter_args} , fh => $self->out
                    );
    $exporter->add($self->data);
    $exporter->commit;
}

sub parse_fixes {
    my ($self,$string,$keep_reading) = @_;

    my $parser = Catmandu::Fix::Parser->new;

    my $fixes;
    my $error =0;

    try {
         $fixes = $parser->parse($string);
         $keep_reading = 0;
    }
    catch {
        if (ref($_) eq 'Catmandu::FixParseError' && $_->message =~ /Can't use an undefined value as a SCALAR reference at/) {
            $keep_reading = 1;
        }
        else {
             $_ =~ s/\n.*//g;
             $self->error($_);
             $error = 1;
        }
    };

    return ($fixes,$keep_reading,$error);
}

1;

__END__

=pod

=head1 NAME

Catmandu::Interactive - An interactive command line interpreter of the Fix language

=head1 SYNOPSIS

   # On the command line
   catmandu run

   # Or, in Perl
   use Catmandu::Interactive;
   use Getopt::Long;

   my $exporter = 'YAML';

   GetOptions("exporter=s" => \$exporter);

   my $app = Catmandu::Interactive->new(exporter => $exporter);

   $app->run();

=head1 DESCRIPTION

This module provide a simple interactive interface to the Catmandu Fix language.

=head1 CONFIGURATION

=over

=item in

Read input from an IO::Handle

=item out

Write output to an IO::Handle

=item silent

If set true, then no headers or prompts are printed

=item data

A hash containing the input record

=item exporter

The name of an exporter package

=item exporter_args

The options for the exporter

=back

=head1 METHODS

=head2 run

Run the interactive environment.

=head1 SEE ALSO

L<Catmandu>

=cut