#! /usr/bin/env ruby

# arv tag usage:
#   arv tag add tag1 [tag2 ...] --object obj_uuid1 [--object obj_uuid2 ...]
#   arv tag remove tag1 [tag2 ...] --object obj_uuid1 [--object obj_uuid2 ...]
#   arv tag remove tag1 [tag2 ...] --all

def tag_add(tag, obj_uuid)
  request_body = {}
  request_body[:api_token] = ENV['ARVADOS_API_TOKEN']

  return client.execute(:api_method => 'arvados.links.create',
                        :parameters => {
                          :name       => tag
                          :link_class => :tag,
                          :head_uuid  => obj_uuid,
                        },
                        :body => request_body,
                        :authenticated => false)
end

def tag_remove(tag, obj_uuid=nil)
  request_body = {}
  request_body[:api_token] = ENV['ARVADOS_API_TOKEN']

  params = { :name => tag, :link_class => :tag }
  if obj_uuid then
    params[:head_uuid] = obj_uuid
  end

  return client.execute(:api_method => 'arvados.links.destroy',
                        :parameters => params,
                        :body => request_body,
                        :authenticated => false)
end

if RUBY_VERSION < '1.9.3' then
  abort <<-EOS
#{$0.gsub(/^\.\//,'')} requires Ruby version 1.9.3 or higher.
  EOS
end

$arvados_api_version = ENV['ARVADOS_API_VERSION'] || 'v1'
$arvados_api_host = ENV['ARVADOS_API_HOST'] or
  abort "#{$0}: fatal: ARVADOS_API_HOST environment variable not set."
$arvados_api_token = ENV['ARVADOS_API_TOKEN'] or
  abort "#{$0}: fatal: ARVADOS_API_TOKEN environment variable not set."

begin
  require 'rubygems'
  require 'google/api_client'
  require 'json'
  require 'pp'
  require 'trollop'
rescue LoadError
  abort <<-EOS
#{$0}: fatal: some runtime dependencies are missing.
Try: gem install pp google-api-client json trollop
  EOS
end

def debuglog(message, verbosity=1)
  $stderr.puts "#{File.split($0).last} #{$$}: #{message}" if $debuglevel >= verbosity
end

module Kernel
  def suppress_warnings
    original_verbosity = $VERBOSE
    $VERBOSE = nil
    result = yield
    $VERBOSE = original_verbosity
    return result
  end
end

if $arvados_api_host.match /local/
  # You probably don't care about SSL certificate checks if you're
  # testing with a dev server.
  suppress_warnings { OpenSSL::SSL::VERIFY_PEER = OpenSSL::SSL::VERIFY_NONE }
end

class Google::APIClient
  def discovery_document(api, version)
    api = api.to_s
    return @discovery_documents["#{api}:#{version}"] ||=
      begin
        response = self.execute!(
                                 :http_method => :get,
                                 :uri => self.discovery_uri(api, version),
                                 :authenticated => false
                                 )
        response.body.class == String ? JSON.parse(response.body) : response.body
      end
  end
end

p = Trollop::Parser.new do
  opt(:all,
      "Remove this tag from all objects under your ownership. Only valid with `tag remove'.",
      :short => :none)
  opt(:object,
      "The UUID of an object to which this tag operation should be applied.",
      :type => :string,
      :multi => true,
      :short => :o)
end

$options = Trollop::with_standard_exception_handling p do
  p.parse ARGV
end

if $options[:all] and ARGV[0] != 'remove'
  abort "#{$0}: the --all option is only valid with the tag 'remove' command"
end

# Set up the API client.

$client ||= Google::APIClient.
  new(:host => $arvados_api_host,
      :application_name => File.split($0).last,
      :application_version => $application_version.to_s)
$arvados = $client.discovered_api('arvados', $arvados_api_version)

results = []
cmd = ARGV.shift
case cmd
when 'add'
  ARGV.each do |tag|
    $options[:object].each do |obj|
      results.push(tag_add(tag, obj))
    end
  end
when 'remove'
  ARGV.each do |tag|
    if $options[:all] then
      results.push(tag_remove(tag))
    else
      $options[:object].each do |obj|
        results.push(tag_remove(tag, obj))
      end
    end
  end
else
  abort "unknown tag command #{cmd}"
end

if global_opts[:human] or global_opts[:pretty] then
  puts Oj.dump(results, :indent => 1)
elsif global_opts[:yaml] then
  puts results.to_yaml
elsif global_opts[:json] then
  puts Oj.dump(results)
elsif results["items"] and results["kind"].match /list$/i
  results['items'].each do |i| puts i['uuid'] end
elsif results['uuid'].nil?
  abort("Response did not include a uuid:\n" +
        Oj.dump(results, :indent => 1) +
        "\n")
else
  results.each do |result|
    puts result['uuid']
  end
end