jam-cloud/ruby/lib/jam_ruby/models/recording.rb

module JamRuby
  class Recording < ActiveRecord::Base

    self.primary_key = 'id'

    attr_accessible :owner, :owner_id, :band, :band_id, :recorded_tracks_attributes, :mixes_attributes, :claimed_recordings_attributes, :name, :description, :genre, :is_public, :duration, as: :admin

    has_many :claimed_recordings, :class_name => "JamRuby::ClaimedRecording", :inverse_of => :recording, :foreign_key => 'recording_id', :dependent => :destroy
    has_many :users, :through => :recorded_tracks, :class_name => "JamRuby::User"
    has_many :mixes, :class_name => "JamRuby::Mix", :inverse_of => :recording, :foreign_key => 'recording_id', :dependent => :destroy
    has_many :recorded_tracks, :class_name => "JamRuby::RecordedTrack", :foreign_key => :recording_id, :dependent => :destroy
    has_many :comments, :class_name => "JamRuby::RecordingComment", :foreign_key => "recording_id"
    has_many :likes, :class_name => "JamRuby::RecordingLiker", :foreign_key => "recording_id"
    has_many :plays, :class_name => "JamRuby::PlayablePlay", :as => :playable, :dependent => :destroy
    has_one :feed, :class_name => "JamRuby::Feed", :inverse_of => :recording, :foreign_key => 'recording_id', :dependent => :destroy

    belongs_to :owner, :class_name => "JamRuby::User", :inverse_of => :owned_recordings, :foreign_key => 'owner_id'
    belongs_to :band, :class_name => "JamRuby::Band", :inverse_of => :recordings
    belongs_to :music_session, :class_name => "JamRuby::MusicSession", :inverse_of => :recordings

    accepts_nested_attributes_for :recorded_tracks, :mixes, :claimed_recordings, allow_destroy: true

    validate :not_already_recording, :on => :create
    validate :not_still_finalizing_previous, :on => :create
    validate :not_playback_recording, :on => :create
    validate :already_stopped_recording
    validate :only_one_mix

    before_save     :sanitize_active_admin
    before_create   :add_to_feed

    def add_to_feed
      feed = Feed.new
      feed.recording = self
    end

    def sanitize_active_admin
      self.owner_id = nil if self.owner_id == ''
      self.band_id = nil if self.band_id == ''
    end

    def comment_count
      self.comments.size
    end

    def has_mix?
      self.mixes.length > 0 && self.mixes.first.completed
    end

    # this can probably be done more efficiently, but David needs this asap for a video
    def grouped_tracks
      tracks = []
      sorted_tracks = self.recorded_tracks.sort { |a,b| a.user.id <=> b.user.id }

      t = Track.new
      t.instrument_ids = []
      sorted_tracks.each_with_index do |track, index|
        if index > 0
          if sorted_tracks[index-1].user.id != sorted_tracks[index].user.id
            t = Track.new
            t.instrument_ids = []
            t.instrument_ids << track.instrument.id
            t.musician = track.user
            tracks << t
          else
            if !t.instrument_ids.include? track.instrument.id
              t.instrument_ids << track.instrument.id
            end
          end
        else
          t.musician = track.user
          t.instrument_ids << track.instrument.id
          tracks << t
        end
      end
      tracks
    end

    def not_already_recording
      if music_session && music_session.is_recording?
        errors.add(:music_session, ValidationMessages::ALREADY_BEING_RECORDED)
      end
    end

    def not_still_finalizing_previous
      # after a recording is done, users need to keep or discard it.
      # this checks if the previous recording is still being finalized

      unless !music_session || music_session.is_recording?
        previous_recording = music_session.most_recent_recording
        if previous_recording
          previous_recording.recorded_tracks.each do |recorded_track|
            # if at least one user hasn't taken any action yet...
            if recorded_track.discard.nil?
              # and they are still around and in this music session still...
              connection = Connection.find_by_client_id(recorded_track.client_id)
              if !connection.nil? && connection.music_session == music_session
                errors.add(:music_session, ValidationMessages::PREVIOUS_RECORDING_STILL_BEING_FINALIZED)
                break
              end
            end
          end
        end
      end
    end

    def not_playback_recording
      if music_session && music_session.is_playing_recording?
        errors.add(:music_session, ValidationMessages::ALREADY_PLAYBACK_RECORDING)
      end
    end

    def already_stopped_recording
      if is_done && is_done_was
        errors.add(:music_session, ValidationMessages::NO_LONGER_RECORDING)
      end
    end


    def only_one_mix
      # we leave mixes as has_many because VRFS-1089 was very hard to do with has_one + cocoon add/remove
      if mixes.length > 1
        errors.add(:mixes, ValidationMessages::ONLY_ONE_MIX)
      end
    end

    def recorded_tracks_for_user(user)
      unless self.users.exists?(user)
        raise PermissionError, "user was not in this session"
      end
      recorded_tracks.where(:user_id=> user.id)
    end

    def has_access?(user)
      return users.exists?(user)
    end

    # Start recording a session.
    def self.start(music_session, owner)
      recording = nil
      # Use a transaction and lock to avoid races.
      music_session.with_lock do
        recording = Recording.new
        recording.music_session = music_session
        recording.owner = owner
        recording.band = music_session.band

        if recording.save
          music_session.connections.each do |connection|
            connection.tracks.each do |track|
              recording.recorded_tracks << RecordedTrack.create_from_track(track, recording)
            end
          end
        end
      end

      recording
    end

    # Stop recording a session
    def stop
      # Use a transaction and lock to avoid races.
      music_session = MusicSession.find_by_id(music_session_id)
      locker = music_session.nil? ? self : music_session
      locker.with_lock do
        self.duration = Time.now - created_at
        self.is_done = true
        self.save
      end

      self
    end


    # Called when a user wants to "claim" a recording. To do this, the user must have been one of the tracks in the recording.
    def claim(user, name, description, genre, is_public)

      unless self.users.exists?(user)
        raise PermissionError, "user was not in this session"
      end

      claimed_recording = ClaimedRecording.new 
      claimed_recording.user = user
      claimed_recording.recording = self
      claimed_recording.name = name
      claimed_recording.description = description
      claimed_recording.genre = genre
      claimed_recording.is_public = is_public
      self.claimed_recordings << claimed_recording

      if claimed_recording.save
        keep(user)
      end

      claimed_recording
    end

    # the user votes to keep their tracks for this recording
    def keep(user)
      recorded_tracks_for_user(user).update_all(:discard => false)

      User.where(:id => user.id).update_all(:first_recording_at => Time.now ) unless user.first_recording_at
    end


    # the user votes to discard their tracks for this recording
    def discard(user)
      recorded_tracks_for_user(user).update_all(:discard => true)

      # check if all recorded_tracks for this recording are discarded
      if recorded_tracks.where('discard = false or discard is NULL').length == 0
        self.all_discarded = true
        self.save(:validate => false)
      end

    end
  
    # Find out if all the tracks for this recording have been uploaded
    def uploaded?
      self.recorded_tracks.each do |recorded_track|
        return false unless recorded_track.fully_uploaded
      end
      return true
    end

    def self.list_downloads(user, limit = 100, since = 0)
      since = 0 unless since || since == '' # guard against nil
      downloads = []

      # That second join is important. It's saying join off of recordings, NOT user. If you take out the
      # ":recordings =>" part, you'll just get the recorded_tracks that I played. Very different!

      # we also only allow you to be told about downloads if you have claimed the recording
      #User.joins(:recordings).joins(:recordings => :recorded_tracks).joins(:recordings => :claimed_recordings)
      RecordedTrack.joins(:recording).joins(:recording => :claimed_recordings)
      .order('recorded_tracks.id')
      .where('recorded_tracks.fully_uploaded = TRUE')
      .where('recorded_tracks.id > ?', since)
      .where('claimed_recordings.user_id = ?', user).limit(limit).each do |recorded_track|
          downloads.push(
              {
                  :type => "recorded_track",
                  :id => recorded_track.client_track_id,
                  :recording_id => recorded_track.recording_id,
                  :length => recorded_track.length,
                  :md5 => recorded_track.md5,
                  :url => recorded_track[:url],
                  :next => recorded_track.id
              }
          )
      end

      latest_recorded_track = downloads[-1][:next] if downloads.length > 0

      Mix.joins(:recording).joins(:recording => :claimed_recordings)
      .order('mixes.id')
      .where('mixes.completed_at IS NOT NULL')
      .where('mixes.id > ?', since)
      .where('claimed_recordings.user_id = ?', user)
      .limit(limit).each do |mix|
        downloads.push(
            {
                :type => "mix",
                :id => mix.id.to_s,
                :recording_id => mix.recording_id,
                :length => mix.ogg_length,
                :md5 => mix.ogg_md5,
                :url => mix.ogg_url,
                :created_at => mix.created_at,
                :next => mix.id
            }
        )
      end

      latest_mix = downloads[-1][:next] if downloads.length > 0

      if !latest_mix.nil? && !latest_recorded_track.nil?
        next_date = [latest_mix, latest_recorded_track].max
      elsif latest_mix.nil?
        next_date = latest_recorded_track
      else
        next_date = latest_mix
      end

      if next_date.nil?
        next_date = since # echo back to the client the same value they passed in, if there are no results
      end

      {
          'downloads' => downloads,
          'next' => next_date.to_s
      }
    end

    def self.list_uploads(user, limit = 100, since = 0)
      since = 0 unless since || since == '' # guard against nil

      uploads = []
      RecordedTrack
        .joins(:recording)
        .where(:user_id => user.id)
        .where(:fully_uploaded => false)
        .where('recorded_tracks.id > ?', since)
        .where("upload_failures <= #{RecordedTrack::MAX_UPLOAD_FAILURES}")
        .where("duration IS NOT NULL")
        .where('all_discarded = false')
        .order('recorded_tracks.id')
        .limit(limit).each do |recorded_track|
          uploads.push({
                         :type => "recorded_track",
                         :client_track_id => recorded_track.client_track_id,
                         :recording_id => recorded_track.recording_id,
                         :next => recorded_track.id
                     })
      end

      next_value = uploads.length > 0 ? uploads[-1][:next].to_s : nil
      if next_value.nil?
        next_value = since # echo back to the client the same value they passed in, if there are no results
      end


      {
        "uploads" => uploads,
        "next" => next_value.to_s
      }
    end

    # Check to see if all files have been uploaded. If so, kick off a mix.
    def upload_complete
      # Don't allow multiple mixes for now.
      raise JamRuby::JamArgumentError unless self.mixes.length == 0

      # FIXME: There's a possible race condition here. If two users complete
      # uploads at the same time, we'll schedule 2 mixes.
      recorded_tracks.each do |recorded_track|
        return unless recorded_track.fully_uploaded
      end

      self.mixes << Mix.schedule(self)

      save
    end


    # meant to be used as a way to 'pluck' a claimed_recording appropriate for user.
    def candidate_claimed_recording
      claimed_recordings.where(is_public: true).first
    end

  private
    def self.validate_user_is_band_member(user, band)
      unless band.users.exists? user
        raise PermissionError, ValidationMessages::USER_NOT_BAND_MEMBER_VALIDATION_ERROR
      end
    end

    def self.validate_user_is_creator(user, creator)
      unless user.id == creator.id
        raise PermissionError, ValidationMessages::PERMISSION_VALIDATION_ERROR
      end
    end

    def self.validate_user_is_musician(user)
      unless user.musician?
        raise PermissionError, ValidationMessages::USER_NOT_MUSICIAN_VALIDATION_ERROR
      end
    end

 end
end