package Mojo::Asset::Memory;

use Mojo::Base 'Mojo::Asset';

use Mojo::Asset::File;

use Mojo::Util 'spurt';

has 'auto_upgrade';

has max_memory_size => sub { $ENV{MOJO_MAX_MEMORY_SIZE} || 262144 };

sub new { shift->SUPER::new(@_, content => '') }

sub add_chunk {

  my ($self, $chunk) = @_;

  # Upgrade if necessary

  $self->{content} .= defined $chunk ? $chunk : '';

  return $self

    if !$self->auto_upgrade || $self->size <= $self->max_memory_size;

  my $file = Mojo::Asset::File->new;

  return $file->add_chunk($self->emit(upgrade => $file)->slurp);

}

sub contains {

  my ($self, $string) = @_;

  my $start = $self->start_range;

  my $pos = index $self->{content}, $string, $start;

  $pos -= $start if $start && $pos >= 0;

  my $end = $self->end_range;

  return $end && ($pos + length $string) >= $end ? -1 : $pos;

}

sub get_chunk {

  my ($self, $start) = @_;

  $start += $self->start_range;

  my $size = 131072;

  if (my $end = $self->end_range) {

    $size = $end + 1 - $start if ($start + $size) > $end;

  }

  return substr shift->{content}, $start, $size;

}

sub move_to {

  my ($self, $to) = @_;

  spurt $self->{content}, $to;

  return $self;

}

sub size { length shift->{content} }

sub slurp { shift->{content} }

1;

=head1 NAME

Mojo::Asset::Memory - In-memory storage for HTTP content

=head1 SYNOPSIS

  use Mojo::Asset::Memory;

  my $mem = Mojo::Asset::Memory->new;

  $mem->add_chunk('foo bar baz');

  say $mem->slurp;

=head1 DESCRIPTION

L<Mojo::Asset::Memory> is an in-memory storage backend for HTTP content.

=head1 EVENTS

L<Mojo::Asset::Memory> inherits all events from L<Mojo::Asset> and can emit

the following new ones.

=head2 upgrade

  $mem->on(upgrade => sub {

    my ($mem, $file) = @_;

    ...

  });

Emitted when asset gets upgraded to a L<Mojo::Asset::File> object.

  $mem->on(upgrade => sub {

    my ($mem, $file) = @_;

    $file->tmpdir('/tmp');

  });

=head1 ATTRIBUTES

L<Mojo::Asset::Memory> inherits all attributes from L<Mojo::Asset> and

implements the following new ones.

=head2 auto_upgrade

  my $upgrade = $mem->auto_upgrade;

  $mem        = $mem->auto_upgrade(1);

Try to detect if content size exceeds C<max_memory_size> limit and

automatically upgrade to a L<Mojo::Asset::File> object.

=head2 max_memory_size

  my $size = $mem->max_memory_size;

  $mem     = $mem->max_memory_size(1024);

Maximum size in bytes of data to keep in memory before automatically upgrading

to a L<Mojo::Asset::File> object, defaults to the value of the

C<MOJO_MAX_MEMORY_SIZE> environment variable or C<262144>.

=head1 METHODS

L<Mojo::Asset::Memory> inherits all methods from L<Mojo::Asset> and implements

the following new ones.

=head2 new

  my $mem = Mojo::Asset::Memory->new;

Construct a new L<Mojo::Asset::Memory> object.

=head2 add_chunk

  $mem     = $mem->add_chunk('foo bar baz');

  my $file = $mem->add_chunk('abc' x 262144);

Add chunk of data and upgrade to L<Mojo::Asset::File> object if necessary.

=head2 contains

  my $position = $mem->contains('bar');

Check if asset contains a specific string.

=head2 get_chunk

  my $bytes = $mem->get_chunk($offset);

Get chunk of data starting from a specific position.

=head2 move_to

  $mem = $mem->move_to('/home/sri/foo.txt');

Move asset data into a specific file.

=head2 size

  my $size = $mem->size;

Size of asset data in bytes.

=head2 slurp

  my $bytes = mem->slurp;

Read all asset data at once.

=head1 SEE ALSO

L<Mojolicious>, L<Mojolicious::Guides>, L<http://mojolicio.us>.

=cut