#!/usr/bin/env ruby

# Arvados cli client
#
# Ward Vandewege <ward@clinicalfuture.com>

require 'fileutils'

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

# read authentication data from arvados configuration file if present
lineno = 0
config_file = File.expand_path('~/.config/arvados/settings.conf')
if File.exist? config_file then
  File.open(config_file, 'r').each do |line|
    lineno = lineno + 1
    # skip comments
    if line.match('^\s*#') then
      next
    end
    var, val = line.chomp.split('=', 2)
    # allow environment settings to override config files.
    if var and val
      ENV[var] ||= val
    else
      warn "#{config_file}: #{lineno}: could not parse `#{line}'"
    end
  end
end

case ARGV[0]
when 'keep'
  ARGV.shift
  @sub = ARGV.shift
  if ['get', 'put', 'ls', 'normalize'].index @sub then
    # Native Arvados
    exec `which arv-#{@sub}`.strip, *ARGV
  elsif ['less', 'check'].index @sub then
    # wh* shims
    exec `which wh#{@sub}`.strip, *ARGV
  else
    puts "Usage: \n" +
      "#{$0} keep ls\n" +
      "#{$0} keep get\n" +
      "#{$0} keep put\n" +
      "#{$0} keep less\n" +
      "#{$0} keep check\n"
  end
  abort
when 'pipeline'
  ARGV.shift
  @sub = ARGV.shift
  if ['run'].index @sub then
    exec `which arv-run-pipeline-instance`.strip, *ARGV
  else
    puts "Usage: \n" +
      "#{$0} pipeline run [...]\n" +
      "(see arv-run-pipeline-instance --help for details)\n"
  end
  abort
when 'tag'
  ARGV.shift
  exec `which arv-tag`.strip, *ARGV
end

ENV['ARVADOS_API_VERSION'] ||= 'v1'

if not ENV.include?('ARVADOS_API_HOST') or not ENV.include?('ARVADOS_API_TOKEN') then
  abort <<-EOS
ARVADOS_API_HOST and ARVADOS_API_TOKEN need to be defined as environment variables.
  EOS
end

begin
  require 'curb'
  require 'rubygems'
  require 'google/api_client'
  require 'json'
  require 'pp'
  require 'trollop'
  require 'andand'
  require 'oj'
  require 'active_support/inflector'
  require 'yaml'
rescue LoadError
  abort <<-EOS

Please install all required gems:

  gem install activesupport andand curb google-api-client json oj trollop

  EOS
end

ActiveSupport::Inflector.inflections do |inflect|
  inflect.irregular 'specimen', 'specimens'
  inflect.irregular 'human', 'humans'
end

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

# do this if you're testing with a dev server and you don't care about SSL certificate checks:
if ENV['ARVADOS_API_HOST_INSECURE']
  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
       # fetch new API discovery doc if stale
       cached_doc = File.expand_path '~/.cache/arvados/discovery_uri.json'
       if not File.exist?(cached_doc) or (Time.now - File.mtime(cached_doc)) > 86400
         response = self.execute!(:http_method => :get,
                                  :uri => self.discovery_uri(api, version),
                                  :authenticated => false)
         FileUtils.makedirs(File.dirname cached_doc)
         File.open(cached_doc, 'w') do |f|
           f.puts response.body
         end
       end

       File.open(cached_doc) { |f| JSON.load f }
     end
 end
end

class ArvadosClient < Google::APIClient
  def execute(*args)
    if args.last.is_a? Hash
      args.last[:headers] ||= {}
      args.last[:headers]['Accept'] ||= 'application/json'
    end
    super(*args)
  end
end

begin
  client = ArvadosClient.new(:host => ENV['ARVADOS_API_HOST'], :application_name => 'arvados-cli', :application_version => '1.0')
  arvados = client.discovered_api('arvados', ENV['ARVADOS_API_VERSION'])
rescue Exception => e
  puts "Failed to connect to Arvados API server: #{e}"
  exit 1
end

def to_boolean(s)
  !!(s =~ /^(true|t|yes|y|1)$/i)
end

def help_methods(discovery_document, resource, method=nil)
  banner = "\n"
  banner += "The #{resource} resource type supports the following methods:"
  banner += "\n\n"
  discovery_document["resources"][resource.pluralize]["methods"].
    each do |k,v|
    description = ''
    if v.include? "description"
      # add only the first line of the discovery doc description
      description = '  ' + v["description"].split("\n").first.chomp
    end
    banner += "   #{sprintf("%20s",k)}#{description}\n"
  end
  banner += "\n"
  STDERR.puts banner

  if not method.nil? and method != '--help' then
    Trollop::die ("Unknown method #{method.inspect} " +
                  "for resource #{resource.inspect}")
  end
  exit 255
end

def help_resources(discovery_document, resource)
  banner = "\n"
  banner += "This Arvados instance supports the following resource types:"
  banner += "\n\n"
  discovery_document["resources"].each do |k,v|
    description = ''
    resource_info = discovery_document["schemas"][k.singularize.capitalize]
    if resource_info and resource_info.include?('description')
      # add only the first line of the discovery doc description
      description = '  ' + resource_info["description"].split("\n").first.chomp
    end
    banner += "   #{sprintf("%30s",k.singularize)}#{description}\n"
  end
  banner += "\n"
  STDERR.puts banner

  if not resource.nil? and resource != '--help' then
    Trollop::die "Unknown resource type #{resource.inspect}"
  end
  exit 255
end

def parse_arguments(discovery_document)
  resource_types = Array.new()
  discovery_document["resources"].each do |k,v|
    resource_types << k.singularize
  end

  global_opts = Trollop::options do
    version __FILE__
    banner "arv: the Arvados CLI tool"
    opt :dry_run, "Don't actually do anything", :short => "-n"
    opt :verbose, "Print some things on stderr"
    opt :format,
        "Set the output format. Must be one of json (default), yaml or uuid.",
        :type => :string,
        :default => 'json'
    opt :short, "Return only UUIDs (equivalent to --format=uuid)"
    opt :resources, "Display list of resources known to this Arvados instance."
    conflicts :short, :format
    stop_on resource_types
  end

  unless %w(json yaml uuid).include?(global_opts[:format])
    $stderr.puts "#{$0}: --format must be one of json, yaml or uuid."
    $stderr.puts "Use #{$0} --help for more information."
    abort
  end

  if global_opts[:short]
    global_opts[:format] = 'uuid'
  end

  resource = ARGV.shift
  if global_opts[:resources] or not resource_types.include?(resource)
    help_resources(discovery_document, resource)
  end

  method = ARGV.shift
  if not (discovery_document["resources"][resource.pluralize]["methods"].
          include?(method))
    help_methods(discovery_document, resource, method)
  end

  discovered_params = discovery_document\
    ["resources"][resource.pluralize]\
    ["methods"][method]["parameters"]
  method_opts = Trollop::options do
    discovered_params.each do |k,v|
      opts = Hash.new()
      opts[:type] = v["type"].to_sym if v.include?("type")
      if [:datetime, :text, :object, :array].index opts[:type]
        opts[:type] = :string                       # else trollop bork
      end
      opts[:default] = v["default"] if v.include?("default")
      opts[:default] = v["default"].to_i if opts[:type] == :integer
      opts[:default] = to_boolean(v["default"]) if opts[:type] == :boolean
      opts[:required] = true if v.include?("required") and v["required"]
      description = ''
      description = '  ' + v["description"] if v.include?("description")
      opt k.to_sym, description, opts
    end
    body_object = discovery_document["resources"][resource.pluralize]["methods"][method]["request"]
    if body_object and discovered_params[resource].nil?
      is_required = true
      if body_object["required"] == false
        is_required = false
      end
      opt resource.to_sym, "#{resource} (request body)", {
        required: is_required,
        type: :string
      }
    end
  end

  discovered_params.each do |k,v|
    k = k.to_sym
    if ['object', 'array'].index(v["type"]) and method_opts.has_key? k
      if method_opts[k].andand.match /^\//
        method_opts[k] = File.open method_opts[k], 'rb' do |f| f.read end
      end
    end
  end
  return resource, method, method_opts, global_opts, ARGV
end

resource_schema, method, method_opts, global_opts, remaining_opts = parse_arguments(arvados.discovery_document)
controller = resource_schema.pluralize

api_method = 'arvados.' + controller + '.' + method

if global_opts[:dry_run]
  if global_opts[:verbose]
    $stderr.puts "#{api_method} #{method_opts.inspect}"
  end
  exit
end

request_parameters = {_profile:true}.merge(method_opts)
resource_body = request_parameters.delete(resource_schema.to_sym)
if resource_body
  request_body = {
    resource_schema => resource_body
  }
else
  request_body = nil
end

case api_method
when
  'arvados.jobs.log_tail_follow'

  # Special case for methods that respond with data streams rather
  # than JSON (TODO: use the discovery document instead of a static
  # list of methods)
  uri_s = eval(api_method).generate_uri(request_parameters)
  Curl::Easy.perform(uri_s) do |curl|
    curl.headers['Accept'] = 'text/plain'
    curl.headers['Authorization'] = "OAuth2 #{ENV['ARVADOS_API_TOKEN']}"
    if ENV['ARVADOS_API_HOST_INSECURE']
      curl.ssl_verify_peer = false
      curl.ssl_verify_host = false
    end
    if global_opts[:verbose]
      curl.on_header { |data| $stderr.write data }
    end
    curl.on_body { |data| $stdout.write data }
  end
  exit 0
else
  result = client.execute(:api_method => eval(api_method),
                          :parameters => request_parameters,
                          :body => request_body,
                          :authenticated => false,
                          :headers => {
                            authorization: 'OAuth2 '+ENV['ARVADOS_API_TOKEN']
                          })
end

begin
  results = JSON.parse result.body
rescue JSON::ParserError => e
  abort "Failed to parse server response:\n" + e.to_s
end

if results["errors"] then
  abort "Error: #{results["errors"][0]}"
end

case global_opts[:format]
when 'json'
  puts Oj.dump(results, :indent => 1)
when 'yaml'
  puts results.to_yaml
else
  if 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
    puts results['uuid']
  end
end