#!/usr/bin/env perl
use strict;
use warnings;
use Getopt::Long qw( :config posix_default bundling no_ignore_case no_auto_abbrev);
use JSON;
use File::Path qw(make_path);

my $source      = undef;
my $destination = undef;
my $token       = undef;

GetOptions( 's|source=s' => \$source, 'd|destination=s' => \$destination, 't|token=s' => \$token) or die usage();

sub usage {
  print "Usage:\n";
  print "  $0 [options]\n\n";
  print "Description:\n";
  print "  This script will recursively download all files if they don't exist\n";
  print "  from a LAADS URL and stores them to the specified path\n\n";
  print "Options:\n";
  print "  -s|--source [URL]         Recursively download files at [URL]\n";
  print "  -d|--destination [path]   Store directory structure to [path]\n";
  print "  -t|--token [token]        Use app token [token] to authenticate\n";
}

sub recurse {
  my $src   = $_[0];
  my $dest  = $_[1];
  my $token = $_[2];
  print "Recursing $src\n";

  my $cmd = "curl -L -b session -s -g --header 'Authorization: Bearer $token' -C - '$src.json'";
  my $message = qx{$cmd};
  my $listing = decode_json($message);
  for my $entry (@{$listing->{content}}){
    if($entry->{size} == 0){
      make_path("$dest/$entry->{name}");
      recurse("$src/$entry->{name}", "$dest/$entry->{name}", $token);
    }
  }

  for my $entry (@{$listing->{content}}){
    if($entry->{size} != 0 and ! -e "$dest/$entry->{name}"){
      print "Downloading $src/$entry->{name} to $dest/$entry->{name}\n";
      my $cmd = "curl -L -b session -s -g --header 'Authorization: Bearer $token' -C - '$src/$entry->{name}' > $dest/$entry->{name}";
      my $result = system($cmd);
      die "FAIL : $cmd" unless $result == 0;
    } else {
      print "Skipping $entry->{name} ...\n";
    }
  }
}


if(!defined($source)){
  print "Source not set\n";
  usage();
  die;
}

if(!defined($destination)){
  print "Destination not set\n";
  usage();
  die;
}

if(!defined($token)){
  print "Token not set\n";
  usage();
  die
}

# make sure the destination exists
make_path($destination) unless -d $destination;

# and download...
recurse($source, $destination, $token);

0;