package LDV::Imgbin;

use strict;
use warnings;
use utf8;

use Mojo::Base 'Mojolicious::Controller';
use JSON qw(encode_json decode_json);
use Mojo::Asset::File;
use Imager;

sub _data_path {
  my ($self, $time) = @_;
  my $root = $self->app->config->{imgbin}->{root};

  return $self->app->home->rel_file("$root/$time.json");
}

sub _image_path {
  my ($self, $time, $ext, $full) = @_;

  return "/images/full/$time.$ext" unless $full;
  return $self->app->home->rel_file("public/images/full/$time.$ext");
}

sub _thumb_path {
  my ($self, $time, $full) = @_;
  my $ext = $self->app->config->{imgbin}->{thumbs_ext};

  return "/images/small/$time.$ext" unless $full;
  return $self->app->home->rel_file("public/images/small/$time.$ext");
}

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

  $self->stash(maxsize => $self->config->{imgbin}->{maxsize});
  $self->render();
}

sub view {
  my ($self) = @_;
  my $time = $self->stash('time') || 0;

  eval {
    my $path = $self->_data_path($time);
    my $data = Mojo::Asset::File->new(path => $path);
    my $json = decode_json($data->slurp);
    die("image expired\n") if (time() > $json->{expire});
    $json->{path} = $self->_image_path($time, $json->{format});

    $self->stash(image => $json); 1;
    $self->render(); 1;
  } or do {
    $self->flash(error => $@);
    $self->redirect_to('/imgbin');
  };

  $self->rendered();
}

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

  eval {
    die ("request too large\n") if $self->req->is_limit_exceeded;

    my $time = time();
    my $conf = $self->app->config->{imgbin};
    my $upload = $self->req->upload('file');
    my $expire = $self->req->param('expire') || 7; # days
    die("no file uploaded\n") unless ($upload and $upload->size > 0);
    die("file too large\n")   if ($upload->size > $conf->{maxsize});

    # hack: don't use memory backend
    {
      my $path = POSIX::tmpnam;
      $upload->move_to($path);
      $upload->asset(Mojo::Asset::File->new(path => $path));
      $upload->asset->cleanup(1); # rearm self-destruction
    }

    my ($im_w, $im_h) = ($conf->{maxres} =~ m/(\d+)x(\d+)/oi);
    Imager->set_file_limits(
      width => $im_w, height => $im_h,
      bytes => $conf->{maxmem},
    );

    my $image = Imager->new(file => $upload->asset->path)
      or die(Imager->errstr() . "\n");

    my $json = {
      comment => $image->tags(name => 'i_comment') // '',
      format  => $image->tags(name => 'i_format'),
      expire  => $time + $expire * 86400, # expired *after* this time
      width   => $image->getwidth,
      height  => $image->getheight,
      name    => $upload->filename,
      size    => $upload->size,
    };

    my ($th_w, $th_h) = ($conf->{thumbs_size} =~ m/(\d+)x(\d+)/oi);
    my $thumb = $image->scale(xpixels => $th_w, ypixels => $th_h, type => 'min');
    $thumb->write(file => $self->_thumb_path($time, 'fullpath'))
      or die $thumb->errstr;
    $upload->move_to($self->_image_path($time, $json->{format}, 'fullpath'));

    my $data = Mojo::Asset::File->new(path => $self->_data_path($time));
    $data->add_chunk(encode_json($json));
    $data->move_to($self->_data_path($time));

    $self->redirect_to("/imgbin/$time");
  } or do {
    $self->app->log->error($@);
    $@ =~ s/\s+ at \s+ .+ \s+ line \s+ \d+//oxi;
    $self->flash(error => $@);
    $self->redirect_to('/imgbin');
  };

  $self->rendered();
}

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

  eval {
    my @images = ();
    my $root = $self->app->config->{imgbin}->{root};
    opendir(my $DH, $root)
      or die("opendir: $!\n");
    my @items = grep { m/\d+\.json/oi } readdir($DH);
    closedir($DH);
    @items = map  { m/(\d+)\.json/oi } @items;
    @items = sort { $b <=> $a } @items;
    foreach my $time (splice(@items, 0, 10)) {
      my $data = Mojo::Asset::File->new(path => $self->_data_path($time));
      my $image = decode_json($data->slurp);
      $image->{path} = $self->_thumb_path($time);
      $image->{url}  = sprintf '/imgbin/%d', $time;
      push @images, $image;
    }

    $self->stash(images => \@images);
    $self->render();
  } or do {
    $self->flash(error => $@);
    $self->redirect_to('/imgbin');
  };
}

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

  eval {
    my $root = $self->app->config->{imgbin}->{root};
    opendir(my $DH, $root)
      or die("opendir: $!\n");
    my @files = grep { m/\d+\.json/oi } readdir($DH);
    my @times = map { s/\.json//oi; $_ } @files;
    closedir($DH);

    my $now = time();
    foreach my $time (@times) {
      my $data  = Mojo::Asset::File->new(path => $self->_data_path($time));
      my $image = decode_json($data->slurp);
      next if $image->{expire} > $now;
      unlink $self->_image_path($time, $image->{format}, 1);
      unlink $self->_thumb_path($time);
    } 1;
  } or do {
    chomp $@;
    $self->app->log->error($@);
    $@ =~ s/\s+ at \s+ .+ \s+ line \s+ \d+//oxi;
    $self->flash(error => $@);
  };
  $self->redirect_to('/imgbin');
  $self->rendered();
}

1;