/*************************************************************************/
/*  library_godot_audio.js                                               */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md).   */
/*                                                                       */
/* 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.                */
/*************************************************************************/

const GodotAudio = {

	$GodotAudio__deps: ['$GodotOS'],
	$GodotAudio: {
		ctx: null,
		input: null,
		driver: null,
		interval: 0,

		init: function(mix_rate, latency, onstatechange, onlatencyupdate) {
			const ctx = new (window.AudioContext || window.webkitAudioContext)({
				sampleRate: mix_rate,
				// latencyHint: latency / 1000 // Do not specify, leave 'interactive' for good performance.
			});
			GodotAudio.ctx = ctx;
			onstatechange(ctx.state); // Immeditately notify state.
			ctx.onstatechange = function() {
				let state = 0;
				switch (ctx.state) {
					case 'suspended':
						state = 0;
						break;
					case 'running':
						state = 1;
						break;
					case 'closed':
						state = 2;
						break;
				}
				onstatechange(state);
			}
			// Update computed latency
			GodotAudio.interval = setInterval(function() {
				let latency = 0;
				if (ctx.baseLatency) {
					latency += GodotAudio.ctx.baseLatency;
				}
				if (ctx.outputLatency) {
					latency += GodotAudio.ctx.outputLatency;
				}
				onlatencyupdate(latency);
			}, 1000);
			GodotOS.atexit(GodotAudio.close_async);
			return ctx.destination.channelCount;
		},

		create_input: function(callback) {
			if (GodotAudio.input) {
				return; // Already started.
			}
			function gotMediaInput(stream) {
				GodotAudio.input = GodotAudio.ctx.createMediaStreamSource(stream);
				callback(GodotAudio.input)
			}
			if (navigator.mediaDevices.getUserMedia) {
				navigator.mediaDevices.getUserMedia({
					"audio": true
				}).then(gotMediaInput, function(e) { out(e) });
			} else {
				if (!navigator.getUserMedia) {
					navigator.getUserMedia = navigator.webkitGetUserMedia || navigator.mozGetUserMedia;
				}
				navigator.getUserMedia({
					"audio": true
				}, gotMediaInput, function(e) { out(e) });
			}
		},

		close_async: function(resolve, reject) {
			const ctx = GodotAudio.ctx;
			GodotAudio.ctx = null;
			// Audio was not initialized.
			if (!ctx) {
				resolve();
				return;
			}
			// Remove latency callback
			if (GodotAudio.interval) {
				clearInterval(GodotAudio.interval);
				GodotAudio.interval = 0;
			}
			// Disconnect input, if it was started.
			if (GodotAudio.input) {
				GodotAudio.input.disconnect();
				GodotAudio.input = null;
			}
			// Disconnect output
			let closed = Promise.resolve();
			if (GodotAudio.driver) {
				closed = GodotAudio.driver.close();
			}
			closed.then(function() {
				return ctx.close();
			}).then(function() {
				ctx.onstatechange = null;
				resolve();
			}).catch(function(e) {
				ctx.onstatechange = null;
				console.error("Error closing AudioContext", e);
				resolve();
			});
		},
	},

	godot_audio_is_available__proxy: 'sync',
	godot_audio_is_available: function () {
		if (!(window.AudioContext || window.webkitAudioContext)) {
			return 0;
		}
		return 1;
	},

	godot_audio_init: function(p_mix_rate, p_latency, p_state_change, p_latency_update) {
		const statechange = GodotOS.get_func(p_state_change);
		const latencyupdate = GodotOS.get_func(p_latency_update);
		return GodotAudio.init(p_mix_rate, p_latency, statechange, latencyupdate);
	},

	godot_audio_resume: function() {
		if (GodotAudio.ctx && GodotAudio.ctx.state != 'running') {
			GodotAudio.ctx.resume();
		}
	},

	godot_audio_capture_start__proxy: 'sync',
	godot_audio_capture_start: function() {
		if (GodotAudio.input) {
			return; // Already started.
		}
		GodotAudio.create_input(function(input) {
			input.connect(GodotAudio.driver.get_node());
		});
	},

	godot_audio_capture_stop__proxy: 'sync',
	godot_audio_capture_stop: function() {
		if (GodotAudio.input) {
			const tracks = GodotAudio.input['mediaStream']['getTracks']();
			for (let i = 0; i < tracks.length; i++) {
				tracks[i]['stop']();
			}
			GodotAudio.input.disconnect();
			GodotAudio.input = null;
		}
	},
};

autoAddDeps(GodotAudio, "$GodotAudio");
mergeInto(LibraryManager.library, GodotAudio);

/**
 * The AudioWorklet API driver, used when threads are available.
 */
const GodotAudioWorklet = {

	$GodotAudioWorklet__deps: ['$GodotAudio'],
	$GodotAudioWorklet: {
		promise: null,
		worklet: null,

		create: function(channels) {
			const path = Module['locateFile']('godot.audio.worklet.js');
			GodotAudioWorklet.promise = GodotAudio.ctx.audioWorklet.addModule(path).then(function() {
				GodotAudioWorklet.worklet = new AudioWorkletNode(
					GodotAudio.ctx,
					'godot-processor',
					{
						'outputChannelCount': [channels]
					}
				);
				return Promise.resolve();
			});
			GodotAudio.driver = GodotAudioWorklet;
		},

		start: function(in_buf, out_buf, state) {
			GodotAudioWorklet.promise.then(function() {
				const node = GodotAudioWorklet.worklet;
				node.connect(GodotAudio.ctx.destination);
				node.port.postMessage({
					'cmd': 'start',
					'data': [state, in_buf, out_buf],
				});
				node.port.onmessage = function(event) {
					console.error(event.data);
				};
			});
		},

		get_node: function() {
			return GodotAudioWorklet.worklet;
		},

		close: function() {
			return new Promise(function(resolve, reject) {
				GodotAudioWorklet.promise.then(function() {
					GodotAudioWorklet.worklet.port.postMessage({
						'cmd': 'stop',
						'data': null,
					});
					GodotAudioWorklet.worklet.disconnect();
					GodotAudioWorklet.worklet = null;
					GodotAudioWorklet.promise = null;
					resolve();
				});
			});
		},
	},

	godot_audio_worklet_create: function(channels) {
		GodotAudioWorklet.create(channels);
	},

	godot_audio_worklet_start: function(p_in_buf, p_in_size, p_out_buf, p_out_size, p_state) {
		const out_buffer = GodotOS.heapSub(HEAPF32, p_out_buf, p_out_size);
		const in_buffer = GodotOS.heapSub(HEAPF32, p_in_buf, p_in_size);
		const state = GodotOS.heapSub(HEAP32, p_state, 4);
		GodotAudioWorklet.start(in_buffer, out_buffer, state);
	},

	godot_audio_worklet_state_wait: function(p_state, p_idx, p_expected, p_timeout) {
		Atomics.wait(HEAP32, (p_state >> 2) + p_idx, p_expected, p_timeout);
		return Atomics.load(HEAP32, (p_state >> 2) + p_idx);
	},

	godot_audio_worklet_state_add: function(p_state, p_idx, p_value) {
		return Atomics.add(HEAP32, (p_state >> 2) + p_idx, p_value);
	},

	godot_audio_worklet_state_get: function(p_state, p_idx) {
		return Atomics.load(HEAP32, (p_state >> 2) + p_idx);
	},
};

autoAddDeps(GodotAudioWorklet, "$GodotAudioWorklet");
mergeInto(LibraryManager.library, GodotAudioWorklet);

/*
 * The deprecated ScriptProcessorNode API, used when threads are disabled.
 */
const GodotAudioScript = {

	$GodotAudioScript__deps: ['$GodotAudio'],
	$GodotAudioScript: {
		script: null,

		create: function(buffer_length, channel_count) {
			GodotAudioScript.script = GodotAudio.ctx.createScriptProcessor(buffer_length, 2, channel_count);
			GodotAudio.driver = GodotAudioScript;
			return GodotAudioScript.script.bufferSize;
		},

		start: function(p_in_buf, p_in_size, p_out_buf, p_out_size, onprocess) {
			GodotAudioScript.script.onaudioprocess = function(event) {
				// Read input
				const inb = GodotOS.heapSub(HEAPF32, p_in_buf, p_in_size);
				const input = event.inputBuffer;
				if (GodotAudio.input) {
					const inlen = input.getChannelData(0).length;
					for (let ch = 0; ch < 2; ch++) {
						const data = input.getChannelData(ch);
						for (let s = 0; s < inlen; s++) {
							inb[s * 2 + ch] = data[s];
						}
					}
				}

				// Let Godot process the input/output.
				onprocess();

				// Write the output.
				const outb = GodotOS.heapSub(HEAPF32, p_out_buf, p_out_size);
				const output = event.outputBuffer;
				const channels = output.numberOfChannels;
				for (let ch = 0; ch < channels; ch++) {
					const data = output.getChannelData(ch);
					// Loop through samples and assign computed values.
					for (let sample = 0; sample < data.length; sample++) {
						data[sample] = outb[sample * channels + ch];
					}
				}
			};
			GodotAudioScript.script.connect(GodotAudio.ctx.destination);
		},

		get_node: function() {
			return GodotAudioScript.script;
		},

		close: function() {
			return new Promise(function(resolve, reject) {
				GodotAudioScript.script.disconnect();
				GodotAudioScript.script.onaudioprocess = null;
				GodotAudioScript.script = null;
				resolve();
			});
		},
	},

	godot_audio_script_create: function(buffer_length, channel_count) {
		return GodotAudioScript.create(buffer_length, channel_count);
	},

	godot_audio_script_start: function(p_in_buf, p_in_size, p_out_buf, p_out_size, p_cb) {
		const onprocess = GodotOS.get_func(p_cb);
		GodotAudioScript.start(p_in_buf, p_in_size, p_out_buf, p_out_size, onprocess);
	},
};

autoAddDeps(GodotAudioScript, "$GodotAudioScript");
mergeInto(LibraryManager.library, GodotAudioScript);
