lighttroupe/luz

module EngineEnvironment
    def init_environment
        $env[:time] = 0.0
        $env[:beat] = 0.0
        $env[:output_width] = $application.width
        $env[:output_height] = $application.height

        # Because of the nature of with_x { } blocks, we only need to set some things once
        # NOTE: an editor GUI *can* mess with these values, though, and this is intentional!

        $env[:last_message_bus_activity_at] = nil                    # set by message bus
        $env[:time_since_message_bus_activity] = 999.0        # like fo'eva

        # Default enter/exit is right in the middle (fully on stage)
        $env[:enter] = 1.0
        $env[:exit] = 0.0

        update_environment
    end

    def update_environment
        beat_scale = @beat_detector.progress            # a fuzzy (0.0 to 1.0 inclusive) measure of progress within the current beat
        bpm = @beat_detector.beats_per_minute

        # Integer beat counts
        $env[:beat_number] = @beat_detector.beat_number                    # integer beat count
        $env[:beats_per_measure] = @beat_detector.beats_per_measure                    # integer beat count
        $env[:beat_index_in_measure] = $env[:beat_number] % $env[:beats_per_measure]

        # Integer measure count
        $env[:measure_number] = $env[:beat_number].div($env[:beats_per_measure])                # TODO: account for measure changes ?

        # Floating point measure scale (0.0 to 1.0)
        $env[:measure_scale] = ($env[:beat_index_in_measure] + beat_scale) / $env[:beats_per_measure]

        # Floating point measure number (eg. measure 503.2)
        $env[:measure] = $env[:measure_number] + $env[:measure_scale]

        # Floating point beat scale (0.0 to 1.0)
        $env[:previous_beat_scale] = $env[:beat_scale]        # TODO: does this need to be initialized for frame 0?
        $env[:beat_scale] = beat_scale                        # fuzzy beat (0.0 to 1.0)

        # Floating point beat count (eg. beat 2012.8)
        $env[:previous_beat] = $env[:beat]
        $env[:beat] = ($env[:beat_number] + beat_scale)
        $env[:beat_delta] = ($env[:beat] - $env[:previous_beat])

        $env[:is_beat] = @beat_detector.is_beat?    # boolean
        $env[:bpm] = bpm
        $env[:bps] = bpm / 60.0
        $env[:seconds_per_beat] = 60.0 / bpm
        $env[:frame_number] = @frame_number

        $env[:previous_time] = $env[:time]
        $env[:time] = @time
        $env[:time_delta] = @time_delta

        $env[:frame_time] = @frame_time                        # TODO: change to 'real world time' or something
        $env[:frame_time_delta] = @frame_time_delta

        # Default birth times: beginning of engine time
        $env[:birth_time] = 0.0
        $env[:birth_beat] = 0

        $env[:child_index] = 0
        $env[:total_children] = 1

        $env[:time_since_message_bus_activity] = ($env[:frame_time] - $env[:last_message_bus_activity_at]) if $env[:last_message_bus_activity_at]
    end
end