/*!
 * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */

import {IExtensionEventCallbackResult} from 'apl-html';
import {ExtensionCommandDefinition, ExtensionEventHandler, IExtension, ILiveDataDefinition, LiveMap} from 'apl-html';
import {ILogger, LoggerFactory} from '../..';
import {createAplExtensionCommandDefinition, createAplExtensionEventHandler} from '../ExtensionCreationUtils';
import {AudioPlayerExtensionObserverInterface, Lyric} from './AudioPlayerExtensionObserverInterface';

/**
 * An APL Extension designed for bi-directional communication between an AudioPlayer and APL document
 * to allow for control and command of audio stream and APL UI.
 *
 */
export class AudioPlayerExtension implements IExtension {
    public static readonly URI: string = 'aplext:audioplayer:10';
    public static readonly COMMAND_PLAY_NAME: string = 'Play';
    public static readonly COMMAND_PAUSE_NAME: string = 'Pause';
    public static readonly COMMAND_PREVIOUS_NAME: string = 'Previous';
    public static readonly COMMAND_NEXT_NAME: string = 'Next';
    public static readonly COMMAND_SEEK_TO_POSITION_NAME: string = 'SeekToPosition';
    public static readonly COMMAND_TOGGLE_NAME: string = 'Toggle';
    public static readonly COMMAND_ADD_LYRICS_VIEWED_NAME: string = 'AddLyricsViewed';
    public static readonly COMMAND_ADD_LYRICS_DURATION_IN_MILLISECONS_NAME: string = 'AddLyricsDurationInMilliseconds';
    public static readonly COMMAND_FLUSH_LYRIC_DATA_NAME: string = 'FlushLyricData';
    public static readonly EVENTHANDLER_ON_PLAYER_ACTIVITY_UPDATED_NAME: string = 'OnPlayerActivityUpdated';
    public static readonly PROPERTY_OFFSET_IN_MILLISECONDS: string = 'offset';
    public static readonly PROPERTY_TOGGLE_NAME: string = 'name';
    public static readonly PROPERTY_TOGGLE_CHECKED: string = 'checked';
    public static readonly PROPERTY_LYRICS_TOKEN: string = 'token';
    public static readonly PROPERTY_LYRICS_VIEWED_LINES: string = 'lines';
    public static readonly PROPERTY_LYRICS_DURATION_IN_MILLISECONDS: string = 'durationInMilliseconds';
    public static readonly SETTINGS_PLAYBACK_STATE_NAME: string = 'playbackStateName';
    public static readonly ACTIVITY_PLAYING: string = 'PLAYING';
    public static readonly ACTIVITY_STOPPED: string = 'STOPPED';
    public static readonly ACTIVITY_PAUSED: string = 'PAUSED';
    public static readonly ACTIVITY_BUFFER_UNDERRUN: string = 'BUFFER_UNDERRUN';

    private logger: ILogger = LoggerFactory.getLogger('AudioPlayerExtension');
    private observer: AudioPlayerExtensionObserverInterface;
    private context: APL.Context;
    private playbackState: LiveMap;
    private playbackStateName: string | undefined;

    public constructor(observer: AudioPlayerExtensionObserverInterface) {
        this.observer = observer;
        this.playbackState = LiveMap.create({});
        this.playbackStateName = undefined;
    }

    /**
     * Return the URI of this extension
     */
    public getUri(): string {
        return AudioPlayerExtension.URI;
    }

    /**
     * The audioplayer extension doesn't add any environment properties to
     * the assigned namespace of the entension at APL1.4:
     */
    public getEnvironment() {
        return {};
    }

    /**
     * Getter for playbackStateName. Used for testing
     */
    public getPlaybackStateName(): string | undefined {
        return this.playbackStateName;
    }

    /**
     * Returns all of the commands supported by the AudioPlayer extension.
     */
    public getExtensionCommands(): ExtensionCommandDefinition[] {
        const uri = AudioPlayerExtension.URI;
        return [
            new ExtensionCommandDefinition({
                uri,
                name: AudioPlayerExtension.COMMAND_PLAY_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false),
            new ExtensionCommandDefinition({
                uri,
                name: AudioPlayerExtension.COMMAND_PAUSE_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false),
            new ExtensionCommandDefinition({
                uri,
                name: AudioPlayerExtension.COMMAND_PREVIOUS_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false),
            new ExtensionCommandDefinition({
                uri, name: AudioPlayerExtension.COMMAND_NEXT_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false),
            new ExtensionCommandDefinition({
                uri, name: AudioPlayerExtension.COMMAND_SEEK_TO_POSITION_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false)
                .property(AudioPlayerExtension.PROPERTY_OFFSET_IN_MILLISECONDS, 0, true),
            new ExtensionCommandDefinition({
                uri, name: AudioPlayerExtension.COMMAND_TOGGLE_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false)
                .property(AudioPlayerExtension.PROPERTY_TOGGLE_NAME, '', true)
                .property(AudioPlayerExtension.PROPERTY_TOGGLE_CHECKED, false, true),
            new ExtensionCommandDefinition({
                uri, name:
                AudioPlayerExtension.COMMAND_ADD_LYRICS_VIEWED_NAME, createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false)
                .property(AudioPlayerExtension.PROPERTY_LYRICS_VIEWED_LINES, [], true)
                .property(AudioPlayerExtension.PROPERTY_LYRICS_TOKEN, '', true),
            new ExtensionCommandDefinition({
                uri, name:
                AudioPlayerExtension.COMMAND_ADD_LYRICS_DURATION_IN_MILLISECONS_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false)
                .property(AudioPlayerExtension.PROPERTY_LYRICS_DURATION_IN_MILLISECONDS, 0, true)
                .property(AudioPlayerExtension.PROPERTY_LYRICS_TOKEN, '', true),
            new ExtensionCommandDefinition({
                uri, name:
                AudioPlayerExtension.COMMAND_FLUSH_LYRIC_DATA_NAME,
                createAplExtensionCommandDefinition
            })
                .allowFastMode(true)
                .requireResolution(false)
        ];
    }

    /**
     * Returns all of the event handlers supported by the AudioPlayer extension.
     */
    public getExtensionEventHandlers(): ExtensionEventHandler[] {
        return [
            new ExtensionEventHandler({
                uri: AudioPlayerExtension.URI,
                name: AudioPlayerExtension.EVENTHANDLER_ON_PLAYER_ACTIVITY_UPDATED_NAME,
                createAplExtensionEventHandler
            })
        ];
    }

    /**
     * Returns all of the event Live Data for the current document
     */
    public getLiveData(): ILiveDataDefinition[] {
        const liveData: ILiveDataDefinition[] = [];
        if (this.playbackStateName) {
            liveData.push({
                name: this.playbackStateName,
                data: this.playbackState
            });
        }
        return liveData;
    }

    /**
     * Sets the Context for later use
     * @param context Context for the current document
     */
    public setContext(context: APL.Context): void {
        this.context = context;
        this.logger.debug(`context is set to ${context}`);
    }

    /**
     * Apply extension settings retrieved from Content.
     * @param settings AudioPlayer settings object.
     */
    public applySettings(settings: object): void {
        this.logger.debug(`AudioPlayerExtension.applySettings`);
        this.playbackStateName = undefined;
        if (settings.hasOwnProperty(AudioPlayerExtension.SETTINGS_PLAYBACK_STATE_NAME)) {
            this.playbackState = LiveMap.create({offset: 0, playerActivity: AudioPlayerExtension.ACTIVITY_STOPPED});
            this.playbackStateName = settings[AudioPlayerExtension.SETTINGS_PLAYBACK_STATE_NAME];
            this.logger.debug(
                `binding ${this.playbackStateName} to playbackState ${this.playbackState}`);
        }
    }

    /**
     * Handles executing custom commands defined by the extension.
     * @param uri the uri of the extension
     * @param commandName the name of the command to execute
     * @param source the source which raised the event that triggered the command
     * @param params the command parameters specified in the extension command definition
     */
    public onExtensionEvent(uri: string, commandName: string, source: object, params: object,
                            resultCallback: IExtensionEventCallbackResult): void {
        let succeeded: boolean = true;

        if (uri === AudioPlayerExtension.URI && this.observer) {
            switch (commandName) {
                case AudioPlayerExtension.COMMAND_PLAY_NAME:
                    this.observer.onAudioPlayerPlay();
                    break;

                case AudioPlayerExtension.COMMAND_PAUSE_NAME:
                    this.observer.onAudioPlayerPause();
                    break;

                case AudioPlayerExtension.COMMAND_PREVIOUS_NAME:
                    this.observer.onAudioPlayerPrevious();
                    break;

                case AudioPlayerExtension.COMMAND_NEXT_NAME:
                    this.observer.onAudioPlayerNext();
                    break;

                case AudioPlayerExtension.COMMAND_SEEK_TO_POSITION_NAME:
                    if (this.confirmEventParams(AudioPlayerExtension.COMMAND_SEEK_TO_POSITION_NAME,
                        [AudioPlayerExtension.PROPERTY_OFFSET_IN_MILLISECONDS], params)) {
                        this.observer.onAudioPlayerSeekToPosition(
                            Number(params[AudioPlayerExtension.PROPERTY_OFFSET_IN_MILLISECONDS]));
                    } else {
                        succeeded = false;
                    }
                    break;

                case AudioPlayerExtension.COMMAND_TOGGLE_NAME:
                    if (this.confirmEventParams(AudioPlayerExtension.COMMAND_TOGGLE_NAME,
                        [AudioPlayerExtension.PROPERTY_TOGGLE_NAME,
                            AudioPlayerExtension.PROPERTY_TOGGLE_CHECKED], params)) {
                        this.observer.onAudioPlayerToggle(
                            params[AudioPlayerExtension.PROPERTY_TOGGLE_NAME] as string,
                            params[AudioPlayerExtension.PROPERTY_TOGGLE_CHECKED] as boolean);
                    } else {
                        succeeded = false;
                    }

                case AudioPlayerExtension.COMMAND_ADD_LYRICS_VIEWED_NAME:
                    if (this.confirmEventParams(AudioPlayerExtension.COMMAND_ADD_LYRICS_VIEWED_NAME,
                        [AudioPlayerExtension.PROPERTY_LYRICS_VIEWED_LINES,
                            AudioPlayerExtension.PROPERTY_LYRICS_TOKEN], params)) {
                        this.observer.onAddLyricsViewed(
                            params[AudioPlayerExtension.PROPERTY_LYRICS_VIEWED_LINES] as Lyric[],
                            params[AudioPlayerExtension.PROPERTY_LYRICS_TOKEN] as string);
                    } else {
                        succeeded = false;
                    }
                    break;

                case AudioPlayerExtension.COMMAND_ADD_LYRICS_DURATION_IN_MILLISECONS_NAME:
                    if (this.confirmEventParams(AudioPlayerExtension.COMMAND_ADD_LYRICS_DURATION_IN_MILLISECONS_NAME,
                        [AudioPlayerExtension.PROPERTY_LYRICS_DURATION_IN_MILLISECONDS,
                            AudioPlayerExtension.PROPERTY_LYRICS_TOKEN], params)) {
                        this.observer.onAddLyricsDurationInMilliseconds(
                            Number(params[AudioPlayerExtension.PROPERTY_LYRICS_DURATION_IN_MILLISECONDS]),
                            params[AudioPlayerExtension.PROPERTY_LYRICS_TOKEN] as string);
                    } else {
                        succeeded = false;
                    }
                    break;

                case AudioPlayerExtension.COMMAND_FLUSH_LYRIC_DATA_NAME:
                    this.observer.onFlushLyricData();
                    break;

                default:
                    this.logger.warn(`Invalid Command: ${commandName}`);
                    succeeded = false;
            }
        } else {
            this.logger.warn('No valid observer is set');
            succeeded = false;
        }

        if (resultCallback) {
            resultCallback.onExtensionEventResult(succeeded);
        }
    }

    private confirmEventParams(tag: string, expectedParams: string[], params: object): boolean {
        let isMissingParams = false;
        expectedParams.forEach((param) => {
            if (!params.hasOwnProperty(param)) {
                isMissingParams = true;
                this.logger.warn(`${tag} is missing a parameter ${param}`);
            }
        });

        return !isMissingParams;
    }

    public reportPlaybackProgress(state: string, offset: number) {
        const newPlaybackState = {offset, playerActivity: state};
        this.playbackState.update(newPlaybackState);
    }

    public reportPlaybackStateChange(state: string, offset: number) {
        this.reportPlaybackProgress(state, offset);
        this.logger.info(`reportPlaybackStateChange: ${state} ${offset}`);

        if (this.context) {
            this.context.invokeExtensionEventHandler(AudioPlayerExtension.URI,
                AudioPlayerExtension.EVENTHANDLER_ON_PLAYER_ACTIVITY_UPDATED_NAME,
                JSON.stringify({playerActivity: state}),
                false
            );
        } else {
            this.logger.warn(`reportPlaybackStateChange: no context is set`);
        }
    }
}