/*

Copyright (C) 1997-2016 Sam Lantinga <slouken@libsdl.org>

This software is provided 'as-is', without any express or implied

warranty. In no event will the authors be held liable for any damages

arising from the use of this software.

Permission is granted to anyone to use this software for any purpose,

including commercial applications, and to alter it and redistribute it

freely.

*/

#include "SDL.h"

#ifdef __EMSCRIPTEN__

#include <emscripten/emscripten.h>

#endif

static SDL_Window *window = NULL;

static SDL_Renderer *renderer = NULL;

static SDL_AudioDeviceID devid_in = 0;

static SDL_AudioDeviceID devid_out = 0;

static void

loop()

{

SDL_bool please_quit = SDL_FALSE;

while (SDL_PollEvent(&e)) {

if (e.type == SDL_QUIT) {

please_quit = SDL_TRUE;

} else if (e.type == SDL_KEYDOWN) {

if (e.key.keysym.sym == SDLK_ESCAPE) {

please_quit = SDL_TRUE;

}

} else if (e.type == SDL_MOUSEBUTTONDOWN) {

if (e.button.button == 1) {

SDL_PauseAudioDevice(devid_out, SDL_TRUE);

SDL_PauseAudioDevice(devid_in, SDL_FALSE);

}

} else if (e.type == SDL_MOUSEBUTTONUP) {

if (e.button.button == 1) {

SDL_PauseAudioDevice(devid_in, SDL_TRUE);

SDL_PauseAudioDevice(devid_out, SDL_FALSE);

}

}

}

SDL_SetRenderDrawColor(renderer, 0, 255, 0, 255);

} else {

SDL_SetRenderDrawColor(renderer, 255, 0, 0, 255);

}

SDL_RenderClear(renderer);

SDL_RenderPresent(renderer);

if (please_quit) {

/* stop playing back, quit. */

SDL_Log("Shutting down.\n");

SDL_PauseAudioDevice(devid_in, 1);

SDL_CloseAudioDevice(devid_in);

SDL_PauseAudioDevice(devid_out, 1);

SDL_CloseAudioDevice(devid_out);

SDL_DestroyRenderer(renderer);

SDL_DestroyWindow(window);

SDL_Quit();

#ifdef __EMSCRIPTEN__

emscripten_cancel_main_loop();

#endif

exit(0);

}

/* Note that it would be easier to just have a one-line function that

calls SDL_QueueAudio() as a capture device callback, but we're

trying to test the API, so we use SDL_DequeueAudio() here. */

while (SDL_TRUE) {

Uint8 buf[1024];

const Uint32 br = SDL_DequeueAudio(devid_in, buf, sizeof (buf));

SDL_QueueAudio(devid_out, buf, br);

if (br < sizeof (buf)) {

break;

}

}

}

int

main(int argc, char **argv)

{

/* (argv[1] == NULL means "open default device.") */

const char *devname = argv[1];

int devcount;

int i;

/* Enable standard application logging */

SDL_LogSetPriority(SDL_LOG_CATEGORY_APPLICATION, SDL_LOG_PRIORITY_INFO);

/* Load the SDL library */

if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_AUDIO) < 0) {

SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't initialize SDL: %s\n", SDL_GetError());

return (1);

}

renderer = SDL_CreateRenderer(window, -1, 0);

SDL_SetRenderDrawColor(renderer, 0, 0, 0, 255);

SDL_RenderClear(renderer);

SDL_RenderPresent(renderer);

SDL_Log("Using audio driver: %s\n", SDL_GetCurrentAudioDriver());

devcount = SDL_GetNumAudioDevices(SDL_TRUE);

for (i = 0; i < devcount; i++) {

SDL_Log(" Capture device #%d: '%s'\n", i, SDL_GetAudioDeviceName(i, SDL_TRUE));

}

SDL_zero(spec);

spec.freq = 44100;

spec.format = AUDIO_F32SYS;

spec.channels = 1;

spec.samples = 1024;

devname ? "'" : "",

devname ? devname : "[[default]]",

devname ? "'" : "");

devid_in = SDL_OpenAudioDevice(argv[1], SDL_TRUE, &spec, &spec, 0);

if (!devid_in) {

SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open an audio device for capture: %s!\n", SDL_GetError());

SDL_Quit();

exit(1);

}

SDL_Log("Opening default playback device...\n");

devid_out = SDL_OpenAudioDevice(NULL, SDL_FALSE, &spec, &spec, 0);

if (!devid_out) {

SDL_LogError(SDL_LOG_CATEGORY_APPLICATION, "Couldn't open an audio device for capture: %s!\n", SDL_GetError());

SDL_Quit();

exit(1);

}

#ifdef __EMSCRIPTEN__

emscripten_set_main_loop(loop, 0, 1);

#else

while (1) { loop(); SDL_Delay(16); }

#endif

return 0;

}