/*
 * MIT License
 *
 * Copyright (c) 2020 Joey Castillo
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include "watch_buzzer.h"
#include "watch_main_loop.h"

#include <emscripten.h>

static bool buzzer_enabled = false;
static uint32_t buzzer_period;

void watch_enable_buzzer(void) {
    buzzer_enabled = true;
    buzzer_period = NotePeriods[BUZZER_NOTE_A4];

    EM_ASM({
        Module['audioContext'] = new (window.AudioContext || window.webkitAudioContext)();
    });
}

void watch_set_buzzer_period(uint32_t period) {
    if (!buzzer_enabled) return;
    buzzer_period = period;
}

void watch_disable_buzzer(void) {
    buzzer_enabled = false;
    buzzer_period = NotePeriods[BUZZER_NOTE_A4];

    EM_ASM({
        if (Module['audioContext']) {
            Module['audioContext'].close();
            Module['audioContext'] = null;
        }
    });
}

void watch_set_buzzer_on(void) {
    if (!buzzer_enabled) return;

    EM_ASM({
        const audioContext = Module['audioContext'];
        if (!audioContext) return;

        if (!(audioContext._oscillator && audioContext._gain)) {
            const oscillator = audioContext.createOscillator();
            const gain = audioContext.createGain();
            oscillator.type = 'triangle';
            oscillator.connect(gain);
            gain.connect(audioContext.destination);
            oscillator.start(0);

            audioContext._oscillator = oscillator;
            audioContext._gain = gain;
        }

        audioContext._oscillator.frequency.value = 1e6/$0;
        audioContext._gain.gain.value = 1;
    }, buzzer_period);
}

void watch_set_buzzer_off(void) {
    if (!buzzer_enabled) return;

    EM_ASM({
        const audioContext = Module['audioContext'];
        if (audioContext && audioContext._gain) {
            audioContext._gain.gain.value = 0;
        }
    });
}

void watch_buzzer_play_note(BuzzerNote note, uint16_t duration_ms) {
    if (note == BUZZER_NOTE_REST) {
        watch_set_buzzer_off();
    } else {
        watch_set_buzzer_period(NotePeriods[note]);
        watch_set_buzzer_on();
    }

    main_loop_sleep(duration_ms);
    watch_set_buzzer_off();
}