/*
 * Spreed WebRTC.
 * Copyright (C) 2013-2014 struktur AG
 *
 * This file is part of Spreed WebRTC.
 *
 * 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 <http://www.gnu.org/licenses/>.
 *
 */
define(['jquery', 'underscore', 'audiocontext', 'webrtc.adapter'], function($, _, AudioContext) {

	// Create AudioContext singleton, if supported.
	var context = AudioContext ? new AudioContext() : null;

	var UserMedia = function(options) {

		this.options = $.extend({}, options);
		this.e = $({}); // Events.

		this.localStream = null;
		this.started = false;

		// Audio level.
		this.audioLevel = 0;
		if (!this.options.noaudio && context && context.createScriptProcessor) {
			this.audioSource = null;
			this.audioProcessor = context.createScriptProcessor(2048, 1, 1);
			this.audioProcessor.onaudioprocess = _.bind(function(event) {
				// Compute audio input level based on raw PCM data.
				if (!this.audioSource) {
					return;
				}
				var input = event.inputBuffer.getChannelData(0);
				var len = input.length
				var total = 0;
				var i = 0;
				while (i < len) {
					total += Math.abs(input[i++]);
				}
				// http://en.wikipedia.org/wiki/Root_mean_square
				var rms = Math.sqrt(total / len);
				this.audioLevel = rms;
				//console.log("this.audioLevel", this.audioLevel);
			}, this);
		}

	};

	// Static.
	UserMedia.testGetUserMedia = function(success_cb, error_cb) {

		console.log("Requesting testGetUserMedia");
		try {
			getUserMedia({
				video: true,
				audio: true
			}, success_cb, error_cb);
		} catch (e) {
			console.error('getUserMedia failed with exception: ' + e.message);
			error_cb(e);
		}

	};

	UserMedia.prototype.doGetUserMedia = function(currentcall, mediaConstraints) {

		if (!mediaConstraints) {
			mediaConstraints = currentcall.mediaConstraints;
		}

		try {
			console.log('Requesting access to local media with mediaConstraints:\n' +
				'  \'' + JSON.stringify(mediaConstraints) + '\'');
			getUserMedia(mediaConstraints, _.bind(this.onUserMediaSuccess, this), _.bind(this.onUserMediaError, this));
			this.started = true;
			return true;
		} catch (e) {
			console.error('getUserMedia failed with exception: ' + e.message);
			return false;
		}

	};

	UserMedia.prototype.onUserMediaSuccess = function(stream) {
		console.log('User has granted access to local media.');

		if (!this.started) {
			stream.stop();
			return;
		}

		// Get notified of end events.
		stream.onended = _.bind(function(event) {
			console.log("User media stream ended.");
			this.stop();
		}, this);

		if (this.audioProcessor && context.createMediaStreamSource) {
			// Connect to audioProcessor.
			this.audioSource = context.createMediaStreamSource(stream);
			//console.log("got source", this.audioSource);
			this.audioSource.connect(this.audioProcessor);
			this.audioProcessor.connect(context.destination);
		}
		this.localStream = stream;

		// Let webrtc handle the rest.
		this.e.triggerHandler("mediasuccess", [this]);

	};

	UserMedia.prototype.onUserMediaError = function(error) {
		console.error('Failed to get access to local media. Error was ' + error.name, error);

		if (!this.started) {
			return;
		}

		// Let webrtc handle the rest.
		this.e.triggerHandler("mediaerror", [this, error]);

	};

	UserMedia.prototype.stop = function() {

		if (this.audioSource) {
			this.audioSource.disconnect();
			this.audioSource = null;
		}
		if (this.localStream) {
			this.localStream.stop()
			this.localStream = null;
		}
		if (this.audioProcessor) {
			this.audioProcessor.disconnect()
		}
		this.audioLevel = 0;
		this.started = false;
		console.log("Stopped user media.");
		this.e.triggerHandler("stopped", [this]);

	};

	UserMedia.prototype.applyAudioMute = function(mute) {

		if (this.localStream) {

			var audioTracks = this.localStream.getAudioTracks();
			if (audioTracks.length === 0) {
				//console.log('No local audio available.');
				return;
			}

			for (i = 0; i < audioTracks.length; i++) {
				audioTracks[i].enabled = !mute;
			}

			if (mute) {
				console.log("Local audio muted.")
			} else {
				console.log("Local audio unmuted.")
			}

		}

		return mute;

	};

	UserMedia.prototype.applyVideoMute = function(mute) {

		if (this.localStream) {

			var videoTracks = this.localStream.getVideoTracks();
			if (videoTracks.length === 0) {
				//console.log('No local video available.');
				return;
			}

			for (i = 0; i < videoTracks.length; i++) {
				videoTracks[i].enabled = !mute;
			}

			if (mute) {
				console.log("Local video muted.")
			} else {
				console.log("Local video unmuted.")
			}

		}

		return mute;

	};

	UserMedia.prototype.addToPeerConnection = function(pc) {

		console.log("Add stream to peer connection", pc, this.localStream);
		if (this.localStream) {
			pc.addStream(this.localStream);
		}

	};

	UserMedia.prototype.attachMediaStream = function(video) {

		//console.log("attach", video, this.localStream);
		attachMediaStream(video, this.localStream);

	};

	return UserMedia;

});