#!/usr/bin/env raku

sub prefix:<❱>(*@args) {
  say "❱ {@args}";
  my \proc = run @args, :out, :err;
  .say if .chars > 0
    for proc.out.slurp(:close), proc.err.slurp(:close);
}

sub prefix:<⁉>(*@args) { ❱ @args unless @args[*-1].IO.f }

sub read-exif-info(Str $file) {
  my %exif;
  my \proc = run 'exiftool', $file, :out;
  for proc.out.slurp(:close).split("\n") -> $line {
    my ($key, $val) = $line.split(':')[0,1];
    next unless defined $val;
    %exif{$key.trim} = $val.trim;
  }
  return %exif;
}

class Image {
  has Str $.basename;
  has Str $!source;
  has Str $!dist-dir;
  has Str $.camera;

  submethod BUILD(IO::Path :$source, Str :$dist-dir) {
    $!basename = $source.basename;
    $!source = $source.path;
    $!dist-dir = $dist-dir;
  }

  method generate(Int :$thumb-geometry, Str :$bg-blur) {
    my $thumb = "$!dist-dir/thumb/{$.basename}";
    ⁉ [|<convert -auto-orient -geometry>, $thumb-geometry, $!source, $thumb];

    my $blur = "$!dist-dir/blur/{$.basename}";
    ⁉ [|<convert -flip -geometry>, $thumb-geometry/4, '-blur', $bg-blur, $thumb, $blur];

    my $large = "$!dist-dir/large/{$.basename}";
    ⁉ ['cp', $!source, $large];
  }

  method get-camera-model {
    my %exif = read-exif-info "$!dist-dir/large/{$.basename}";
    my $make = %exif<Make> ?? %exif<Make> !! '';
    my $model = %exif{'Camera Model Name'} ?? %exif{'Camera Model Name'} !! '';
    $model ~~ s/$make //; # Don't stotter
    $model = 'Unknown camera' if $model eq '';
    $!camera = "$make $model".trim;
  }

  method tag(Str $class) {
    "<img class='{$class}' src='./{$class}/{$.basename}' />"
  }
}

class Tag {
  has Str $.name;
  has Str $.text;
  has Str %.params;
  has Tag @.succ;

  method has-text returns Bool { defined $.text }
  method has-succ returns Bool { defined $.succ }

  method open returns Str {"<{$.name}{self.params}>" }
  method close returns Str { "</{$.name}>" }

  method params returns Str {
    return '' unless defined %!params;
    my @params;
    for %!params.kv -> $key, $val {
      push @params, " $key='$val'";
    }
    return @params.join;
  }
}

sub recurse-tags(@open-stack) {
  my @close-stack;
  for @open-stack -> $tag {
    say $tag.open;
    say $tag.text if $tag.has-text;
    unshift @close-stack, $tag;
  }
  for @close-stack -> $tag {
    say $tag.close;
    recurse-tags $tag.succ if $tag.has-succ;
  }
}

sub dist-dirs(Str \dist-dir --> List) { dist-dir <<~>> </large /blur /thumb> }

sub ensure-directories(Str \dist-dir) {
  mkdir dist-dir unless dist-dir.IO.d;
  mkdir $_ unless .IO.d for dist-dirs dist-dir;
}

sub walk-dir(Str \dir, :&onFile, :&onDir = sub (\dir) {} ) {
  return unless dir.IO.d;
  for dir(dir) -> $fh {
    given $fh {
      when .d { walk-dir $fh.path, :&onFile, :&onDir }
      default { &onFile($fh.path) }
    }
  }
  &onDir(dir);
}

sub cleanup-nonexistent (Str \dist-dir, @images) {
  my $basenames = set @images.map:{ $_.basename };
  walk-dir dist-dir,
    onFile => sub (\file) {
      unlink file if file.IO.basename ∉ $basenames
    };
}

sub make-mr-proper(Str \dist-dir) {
  walk-dir dist-dir,
    onFile => sub (\file) { unlink file },
    onDir => sub (\dir) { rmdir dir };
}

sub camera-stats(@images) {
  my %cameras;
  %cameras{.camera}++ for @images;
  return %cameras.sort(*.value).reverse;
}

multi MAIN(
  Bool :$mr-proper,             #= Clean output dir
  Str :$in-dir = './in',        #= Input dir
  Str :$dist-dir = './dist',    #= Output dir
  Int :$thumb-geometry = 800,   #= Thumbnail geometry
  Str :$bg-blur = '0x8',        #= Background blur factor
  Bool :$randomize = True,      #= Randomize order of images
  Str :$title = 'Katana album', #= Album title
  Int :$degree = 4,             #= Degree of parallelism
) {

  my @html-elems;
  push @html-elems, Tag.new: name => 'html',
    params => (
      xmlns => 'http://www.w3.org/1999/xhtml',
      lang => 'en',
      'xml:lang' => 'en'
    );

  push @html-elems, Tag.new: name => 'header',
    succ => [Tag.new: name => 'body'];

  push @html-elems, Tag.new: name => 'title',
    text => $title;

  recurse-tags @html-elems;

  exit;

  my @images = dir($in-dir, test => { "$in-dir/$_".IO.f }).map:{
    Image.new: source => $_, :$dist-dir
  };
  say "Found {@images.elems} images";

  @images = @images.pick: * if $randomize;
  cleanup-nonexistent $dist-dir, @images;
  make-mr-proper $dist-dir if $mr-proper;
  ensure-directories $dist-dir;

  @images.hyper(:$degree).map:{
    .get-camera-model;
    .generate: :$thumb-geometry, :$bg-blur;
  };

  .say for camera-stats @images;
}