require 'sinatra/base'
require 'qless'

# Much of this is shamelessly poached from the resque web client

module Qless
  class Server < Sinatra::Base
    # Path-y-ness
    dir = File.dirname(File.expand_path(__FILE__))
    set :views        , "#{dir}/server/views"
    set :public_folder, "#{dir}/server/static"

    # For debugging purposes at least, I want this
    set :reload_templates, true

    # I'm not sure what this option is -- I'll look it up later
    # set :static, true

    attr_reader :client

    def initialize(client)
      @client = client
      super
    end

    helpers do
      include Rack::Utils

      def url_path(*path_parts)
        [ path_prefix, path_parts ].join("/").squeeze('/')
      end
      alias_method :u, :url_path

      def path_prefix
        request.env['SCRIPT_NAME']
      end

      def url_with_modified_query
        url = URI(request.url)
        existing_query = Rack::Utils.parse_query(url.query)
        url.query = Rack::Utils.build_query(yield existing_query)
        url.to_s
      end

      def page_url(offset)
        url_with_modified_query do |query|
          query.merge('page' => current_page + offset)
        end
      end

      def next_page_url
        page_url 1
      end

      def prev_page_url
        page_url -1
      end

      def current_page
        @current_page ||= begin
          Integer(params[:page])
        rescue
          1
        end
      end

      PAGE_SIZE = 25
      def pagination_values
        start = (current_page - 1) * PAGE_SIZE
        [start, start + PAGE_SIZE]
      end

      def paginated(qless_object, method, *args)
        qless_object.send(method, *(args + pagination_values))
      end

      def tabs
        return [
          {:name => 'Queues'  , :path => '/queues'  },
          {:name => 'Workers' , :path => '/workers' },
          {:name => 'Track'   , :path => '/track'   },
          {:name => 'Failed'  , :path => '/failed'  },
          {:name => 'Config'  , :path => '/config'  },
          {:name => 'About'   , :path => '/about'   }
        ]
      end

      def application_name
        return client.config['application']
      end

      def queues
        return client.queues.counts
      end

      def tracked
        return client.jobs.tracked
      end

      def workers
        return client.workers.counts
      end

      def failed
        return client.jobs.failed
      end

      # Return the supplied object back as JSON
      def json(obj)
        content_type :json
        obj.to_json
      end

      # Make the id acceptable as an id / att in HTML
      def sanitize_attr(attr)
        return attr.gsub(/[^a-zA-Z\:\_]/, '-')
      end

      # What are the top tags? Since it might go on, say, every
      # page, then we should probably be caching it
      def top_tags
        @top_tags ||= {
          :top     => client.tags,
          :fetched => Time.now
        }
        if (Time.now - @top_tags[:fetched]) > 60 then
          @top_tags = {
            :top     => client.tags,
            :fetched => Time.now
          }
        end
        @top_tags[:top]
      end

      def strftime(t)
        # From http://stackoverflow.com/questions/195740/how-do-you-do-relative-time-in-rails
        diff_seconds = Time.now - t
        case diff_seconds
          when 0 .. 59
            "#{diff_seconds.to_i} seconds ago"
          when 60 ... 3600
            "#{(diff_seconds/60).to_i} minutes ago"
          when 3600 ... 3600*24
            "#{(diff_seconds/3600).to_i} hours ago"
          when (3600*24) ... (3600*24*30)
            "#{(diff_seconds/(3600*24)).to_i} days ago"
          else
            t.strftime('%b %e, %Y %H:%M:%S %Z (%z)')
        end
      end
    end

    get '/?' do
      erb :overview, :layout => true, :locals => { :title => "Overview" }
    end

    # Returns a JSON blob with the job counts for various queues
    get '/queues.json' do
      json(client.queues.counts)
    end

    get '/queues/?' do
      erb :queues, :layout => true, :locals => {
        :title   => 'Queues'
      }
    end

    # Return the job counts for a specific queue
    get '/queues/:name.json' do
      json(client.queues[params[:name]].counts)
    end

    filtered_tabs = %w[ running scheduled stalled depends recurring ].to_set
    get '/queues/:name/?:tab?' do
      queue = client.queues[params[:name]]
      tab   = params.fetch('tab', 'stats')

      jobs = if tab == 'waiting'
        queue.peek(20)
      elsif filtered_tabs.include?(tab)
        paginated(queue.jobs, tab).map { |jid| client.jobs[jid] }
      else
        []
      end

      erb :queue, :layout => true, :locals => {
        :title   => "Queue #{params[:name]}",
        :tab     => tab,
        :jobs    => jobs,
        :queue   => client.queues[params[:name]].counts,
        :stats   => queue.stats
      }
    end

    get '/failed.json' do
      json(client.jobs.failed)
    end

    get '/failed/?' do
      # qless-core doesn't provide functionality this way, so we'll
      # do it ourselves. I'm not sure if this is how the core library
      # should behave or not.
      erb :failed, :layout => true, :locals => {
        :title  => 'Failed',
        :failed => client.jobs.failed.keys.map { |t| client.jobs.failed(t).tap { |f| f['type'] = t } }
      }
    end

    get '/failed/:type/?' do
      erb :failed_type, :layout => true, :locals => {
        :title  => 'Failed | ' + params[:type],
        :type   => params[:type],
        :failed => paginated(client.jobs, :failed, params[:type])
      }
    end

    get '/track/?' do
      erb :track, :layout => true, :locals => {
        :title   => 'Track'
      }
    end

    get '/jobs/:jid' do
      erb :job, :layout => true, :locals => {
        :title => "Job | #{params[:jid]}",
        :jid   => params[:jid],
        :job   => client.jobs[params[:jid]]
      }
    end

    get '/workers/?' do
      erb :workers, :layout => true, :locals => {
        :title   => 'Workers'
      }
    end

    get '/workers/:worker' do
      erb :worker, :layout => true, :locals => {
        :title  => 'Worker | ' + params[:worker],
        :worker => client.workers[params[:worker]].tap { |w|
          w['jobs']    = w['jobs'].map { |j| client.jobs[j] }
          w['stalled'] = w['stalled'].map { |j| client.jobs[j] }
          w['name']    = params[:worker]
        }
      }
    end

    get '/tag/?' do
      jobs = paginated(client.jobs, :tagged, params[:tag])
      erb :tag, :layout => true, :locals => {
        :title => "Tag | #{params[:tag]}",
        :tag   => params[:tag],
        :jobs  => jobs['jobs'].map { |jid| client.jobs[jid] },
        :total => jobs['total']
      }
    end

    get '/config/?' do
      erb :config, :layout => true, :locals => {
        :title   => 'Config',
        :options => client.config.all
      }
    end

    get '/about/?' do
      erb :about, :layout => true, :locals => {
        :title   => 'About'
      }
    end

    # These are the bits where we accept AJAX requests
    post "/track/?" do
      # Expects a JSON-encoded hash with a job id, and optionally some tags
      data = JSON.parse(request.body.read)
      job = client.jobs[data["id"]]
      if not job.nil?
        data.fetch("tags", false) ? job.track(*data["tags"]) : job.track()
        if request.xhr?
          json({ :tracked => [job.jid] })
        else
          redirect to('/track')
        end
      else
        if request.xhr?
          json({ :tracked => [] })
        else
          redirect to(request.referrer)
        end
      end
    end

    post "/untrack/?" do
      # Expects a JSON-encoded array of job ids to stop tracking
      jobs = JSON.parse(request.body.read).map { |jid| client.jobs[jid] }.select { |j| not j.nil? }
      # Go ahead and cancel all the jobs!
      jobs.each do |job|
        job.untrack()
      end
      return json({ :untracked => jobs.map { |job| job.jid } })
    end

    post "/priority/?" do
      # Expects a JSON-encoded dictionary of jid => priority
      response = Hash.new
      r = JSON.parse(request.body.read)
      r.each_pair do |jid, priority|
        begin
          client.jobs[jid].priority = priority
          response[jid] = priority
        rescue
          response[jid] = 'failed'
        end
      end
      return json(response)
    end

    post "/tag/?" do
      # Expects a JSON-encoded dictionary of jid => [tag, tag, tag]
      response = Hash.new
      JSON.parse(request.body.read).each_pair do |jid, tags|
        begin
          client.jobs[jid].tag(*tags)
          response[jid] = tags
        rescue
          response[jid] = 'failed'
        end
      end
      return json(response)
    end

    post "/untag/?" do
      # Expects a JSON-encoded dictionary of jid => [tag, tag, tag]
      response = Hash.new
      JSON.parse(request.body.read).each_pair do |jid, tags|
        begin
          client.jobs[jid].untag(*tags)
          response[jid] = tags
        rescue
          response[jid] = 'failed'
        end
      end
      return json(response)
    end

    post "/move/?" do
      # Expects a JSON-encoded hash of id: jid, and queue: queue_name
      data = JSON.parse(request.body.read)
      if data["id"].nil? or data["queue"].nil?
        halt 400, "Need id and queue arguments"
      else
        job = client.jobs[data["id"]]
        if job.nil?
          halt 404, "Could not find job"
        else
          job.move(data["queue"])
          return json({ :id => data["id"], :queue => data["queue"]})
        end
      end
    end

    post "/undepend/?" do
      # Expects a JSON-encoded hash of id: jid, and queue: queue_name
      data = JSON.parse(request.body.read)
      if data["id"].nil?
        halt 400, "Need id"
      else
        job = client.jobs[data["id"]]
        if job.nil?
          halt 404, "Could not find job"
        else
          job.undepend(data['dependency'])
          return json({:id => data["id"]})
        end
      end
    end

    post "/retry/?" do
      # Expects a JSON-encoded hash of id: jid, and queue: queue_name
      data = JSON.parse(request.body.read)
      if data["id"].nil?
        halt 400, "Need id"
      else
        job = client.jobs[data["id"]]
        if job.nil?
          halt 404, "Could not find job"
        else
          queue = job.raw_queue_history[-1]["q"]
          job.move(queue)
          return json({ :id => data["id"], :queue => queue})
        end
      end
    end

    # Retry all the failures of a particular type
    post "/retryall/?" do
      # Expects a JSON-encoded hash of type: failure-type
      data = JSON.parse(request.body.read)
      if data["type"].nil?
        halt 400, "Neet type"
      else
        return json(client.jobs.failed(data["type"], 0, 500)['jobs'].map do |job|
          queue = job.raw_queue_history[-1]["q"]
          job.move(queue)
          { :id => job.jid, :queue => queue}
        end)
      end
    end

    post "/cancel/?" do
      # Expects a JSON-encoded array of job ids to cancel
      jobs = JSON.parse(request.body.read).map { |jid| client.jobs[jid] }.select { |j| not j.nil? }
      # Go ahead and cancel all the jobs!
      jobs.each do |job|
        job.cancel()
      end

      if request.xhr?
        return json({ :canceled => jobs.map { |job| job.jid } })
      else
        redirect to(request.referrer)
      end
    end

    post "/cancelall/?" do
      # Expects a JSON-encoded hash of type: failure-type
      data = JSON.parse(request.body.read)
      if data["type"].nil?
        halt 400, "Neet type"
      else
        return json(client.jobs.failed(data["type"])['jobs'].map do |job|
          job.cancel()
          { :id => job.jid }
        end)
      end
    end

    # start the server if ruby file executed directly
    run! if app_file == $0
  end
end