/*

osc.mjs - <short description TODO>

Copyright (C) 2022 Strudel contributors - see <https://codeberg.org/uzu/strudel/src/branch/main/packages/osc/osc.mjs>

This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details. You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.

*/

import { logger, parseNumeral, register, isNote, noteToMidi, ClockCollator } from '@strudel/core';

let connection; // Promise<OSC>

function connect() {

  if (!connection) {

    // make sure this runs only once

    connection = new Promise((resolve, reject) => {

      const ws = new WebSocket('ws://localhost:8080');

      ws.addEventListener('open', (event) => {

        logger(`[osc] websocket connected`);

        resolve(ws);

      });

      ws.addEventListener('close', (event) => {

        logger(`[osc] websocket closed`);

        connection = undefined; // allows new connection afterwards

        console.log('[osc] disconnected');

        reject('OSC connection closed');

      });

      ws.addEventListener('error', (err) => reject(err));

    }).catch((err) => {

      connection = undefined;

      throw new Error('Could not connect to OSC server. Is it running?');

    });

  }

  return connection;

}

export function parseControlsFromHap(hap, cps) {

  hap.ensureObjectValue();

  const cycle = hap.wholeOrPart().begin.valueOf();

  const delta = hap.duration.valueOf() / cps;

  const controls = Object.assign({}, { cps, cycle, delta }, hap.value);

  // make sure n and note are numbers

  controls.n && (controls.n = parseNumeral(controls.n));

  if (typeof controls.note !== 'undefined') {

    if (isNote(controls.note)) {

      controls.midinote = noteToMidi(controls.note, controls.octave || 3);

    } else {

      controls.note = parseNumeral(controls.note);

    }

  }

  controls.bank && (controls.s = controls.bank + controls.s);

  controls.roomsize && (controls.size = parseNumeral(controls.roomsize));

  // speed adjustment for CPS is handled on the DSP side in superdirt and pattern side in Strudel,

  // so we need to undo the adjustment before sending the message to superdirt.

  controls.unit === 'c' && controls.speed != null && (controls.speed = controls.speed / cps);

  const channels = controls.channels;

  channels != undefined && (controls.channels = JSON.stringify(channels));

  return controls;

}

const collator = new ClockCollator({});

export async function oscTrigger(hap, currentTime, cps = 1, targetTime) {

  const ws = await connect();

  const controls = parseControlsFromHap(hap, cps);

  const keyvals = Object.entries(controls).flat();

  const ts = collator.calculateTimestamp(currentTime, targetTime) * 1000;

  const msg = { address: '/dirt/play', args: keyvals, timestamp: ts };

  if ('oschost' in hap.value) {

    msg['host'] = hap.value['oschost'];

  }

  if ('oscport' in hap.value) {

    msg['port'] = hap.value['oscport'];

  }

  ws.send(JSON.stringify(msg));

}

/**

 *

 * Sends each hap as an OSC message, which can be picked up by SuperCollider or any other OSC-enabled software.

 * For more info, read [MIDI & OSC in the docs](https://strudel.cc/learn/input-output/)

 *

 * @name osc

 * @memberof Pattern

 * @returns Pattern

 */

export const osc = register('osc', (pat) => pat.onTrigger(oscTrigger));