/*
Copyright 2017 Michael Telatynski <7t3chguy@gmail.com>
Copyright 2021 Šimon Brandner <simon.bra.ag@gmail.com>

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

import SettingsStore from "./settings/SettingsStore";
import { SettingLevel } from "./settings/SettingLevel";
import { setMatrixCallAudioInput, setMatrixCallVideoInput } from "matrix-js-sdk/src/matrix";
import EventEmitter from 'events';

interface IMediaDevices {
    audioOutput: Array<MediaDeviceInfo>;
    audioInput: Array<MediaDeviceInfo>;
    videoInput: Array<MediaDeviceInfo>;
}

export enum MediaDeviceHandlerEvent {
    AudioOutputChanged = "audio_output_changed",
    AudioInputChanged = "audio_input_changed",
    VideoInputChanged = "video_input_changed",
}

export default class MediaDeviceHandler extends EventEmitter {
    private static internalInstance;

    public static get instance(): MediaDeviceHandler {
        if (!MediaDeviceHandler.internalInstance) {
            MediaDeviceHandler.internalInstance = new MediaDeviceHandler();
        }
        return MediaDeviceHandler.internalInstance;
    }

    static async hasAnyLabeledDevices(): Promise<boolean> {
        const devices = await navigator.mediaDevices.enumerateDevices();
        return devices.some(d => Boolean(d.label));
    }

    static async getDevices(): Promise<IMediaDevices> {
        // Only needed for Electron atm, though should work in modern browsers
        // once permission has been granted to the webapp

        try {
            const devices = await navigator.mediaDevices.enumerateDevices();

            const audioOutput = [];
            const audioInput = [];
            const videoInput = [];

            devices.forEach((device) => {
                switch (device.kind) {
                    case 'audiooutput': audioOutput.push(device); break;
                    case 'audioinput': audioInput.push(device); break;
                    case 'videoinput': videoInput.push(device); break;
                }
            });

            return {
                audioOutput: audioOutput,
                audioInput: audioInput,
                videoInput: videoInput,
            };
        } catch (error) {
            console.log('Unable to refresh WebRTC Devices: ', error);
        }
    }

    static loadDevices() {
        const audioDeviceId = SettingsStore.getValue("webrtc_audioinput");
        const videoDeviceId = SettingsStore.getValue("webrtc_videoinput");

        setMatrixCallAudioInput(audioDeviceId);
        setMatrixCallVideoInput(videoDeviceId);
    }

    public setAudioOutput(deviceId: string) {
        SettingsStore.setValue("webrtc_audiooutput", null, SettingLevel.DEVICE, deviceId);
        this.emit(MediaDeviceHandlerEvent.AudioOutputChanged, deviceId);
    }

    public setAudioInput(deviceId: string) {
        SettingsStore.setValue("webrtc_audioinput", null, SettingLevel.DEVICE, deviceId);
        setMatrixCallAudioInput(deviceId);
        this.emit(MediaDeviceHandlerEvent.AudioInputChanged, deviceId);
    }

    public setVideoInput(deviceId: string) {
        SettingsStore.setValue("webrtc_videoinput", null, SettingLevel.DEVICE, deviceId);
        setMatrixCallVideoInput(deviceId);
        this.emit(MediaDeviceHandlerEvent.VideoInputChanged, deviceId);
    }

    static getAudioOutput(): string {
        return SettingsStore.getValueAt(SettingLevel.DEVICE, "webrtc_audiooutput");
    }

    static getAudioInput(): string {
        return SettingsStore.getValueAt(SettingLevel.DEVICE, "webrtc_audioinput");
    }

    static getVideoInput(): string {
        return SettingsStore.getValueAt(SettingLevel.DEVICE, "webrtc_videoinput");
    }
}