(define-module (pip-tui pulseaudio)

#:use-module (system foreign)

#:use-module (rnrs bytevectors)

#:use-module (pip-tui action)

#:export (%audio-buffers

audio-iterate

audio-state

audio-finalize

audio-is-finalized?

audio-samples-written

audio-update-time

audio-time->index

tone

simple-tone

noise

simple-noise

Beep

pulseaudio-set-write-cb!

pulseaudio-idle-handler))

(define (audio-iterate)

"This must be called at regular intervals in the main

loop so that the audio is processed."

(%audio-iterate))

(define (audio-state)

"This returns a symbol that described the current state

of the pulseaudio interface. One of 'unconnected, 'connecting,

'authorizing, 'setting-name, 'failed, 'terminated', or 'ready"

(%audio-state))

(define (audio-finalize)

"This will shut down the audio system gracefully."

(%audio-finalize))

(define (audio-is-finalized?)

"Returns #t if the audio system has been shut down with (audio-finalize)"

(%audio-is-finalized?))

(define (audio-samples-written)

"Returns a count of the number of samples written to the audio

system since it initialized."

(%audio-samples-written))

(define (tone channel time parameters)

"Then enqueues a tone to play on the given CHANNEL, starting at the given TIME,

as described by a list of PARAMETERS. PARAMETERS is a list of 12 numeric values

which are

DURATION_ATTACK, DURATION_DECAY, DURATION_SUSTAIN, DURATION_RELEASE in seconds

FREQUENCY_INITIAL, FREQUENCY_ATTACK, FREQUENCY_SUSTAIN, FREQUENCY_RELEASE in Hz

AMPLITUDE_ATTACK, AMPLITUDE_SUSTAIN from 0.0 to 1.0

DUTY, which is ratio of up to down in the waveform from ~0.3 to ~0.7,

WAVEFORM 0=square 1=sine"

(%tone channel time parameters))

(define (simple-tone channel time parameters)

"Then enqueues a square wave tone play on the given CHANNEL, starting at the given TIME,

as described by a list of PARAMETERS. PARAMETERS is a list of 5 numeric values

which are

DURATION_DECAY, DURATION_SUSTAIN in seconds

FREQUENCY in Hz

AMPLITUDE_ATTACK, AMPLITUDE_SUSTAIN from 0.0 to 1.0"

(%simple-tone channel time parameters))

(define (noise channel time parameters)

"Then enqueues a noise to play on the given CHANNEL, starting at the given TIME,

as described by a list of PARAMETERS. PARAMETERS is a list of 12 numeric values

which are

DURATION_ATTACK, DURATION_DECAY, DURATION_SUSTAIN, DURATION_RELEASE in seconds

FREQUENCY_INITIAL, FREQUENCY_ATTACK, FREQUENCY_SUSTAIN, FREQUENCY_RELEASE in Hz

AMPLITUDE_ATTACK, AMPLITUDE_SUSTAIN from 0 to 1.0

DUTY, which is ratio of up to down in the waveform from ~0.3 to ~0.7,

WAVEFORM 0=square 1=sine"

(%noise channel time parameters))

(define (simple-noise channel time parameters)

"Then enqueues a square wave noise to play on the given CHANNEL, starting at the given TIME,

as described by a list of PARAMETERS. PARAMETERS is a list of 5 numeric values

which are

DURATION_DECAY, DURATION_SUSTAIN in seconds

FREQUENCY in Hz

AMPLITUDE_ATTACK, AMPLITUDE_SUSTAIN from 0 to 1.0"

(%simple-noise channel time parameters))

(define (Beep)

"This enqueues a beep to play on channel zero as soon as possible."

(%beep))

(define (pulseaudio-set-write-cb! func)

"This registers a callback function to be called whenever Pulseaudio

is preparing to write new samples. The callback function should take

two parameters: N and TIME-TO-LIVE. N is the number of samples being

requested, and TIME-TO-LIVE is the number of microseconds until these

samples actually play."

(set! %audio-write-cb func))

(define (audio-idle-action-activate TT event state)

(when (idle-event? event)

(audio-iterate)))

(define (pulseaudio-idle-handler)

(action-new "audio-idle" #t '() audio-idle-action-activate #f))

(load-extension "piptui" "pip_pulseaudio_init")