import {
    AbstractInput,
    FilterMode,
    InputConsumer,
    InputConsumerType,
    InputEvents,
    InputStartError,
    InputState,
    LevelMeter,
} from "tc-shared/voice/RecorderBase";
import {audio} from "tc-native/connection";
import {tr} from "tc-shared/i18n/localize";
import {Registry} from "tc-shared/events";
import {Filter, FilterType, FilterTypeClass} from "tc-shared/voice/Filter";
import {NativeFilter, NStateFilter, NThresholdFilter, NVoiceLevelFilter} from "./AudioFilter";
import {IDevice} from "tc-shared/audio/recorder";
import {LogCategory, logTrace, logWarn} from "tc-shared/log";
import {Settings, settings} from "tc-shared/settings";
import NativeFilterMode = audio.record.FilterMode;

export class NativeInput implements AbstractInput {
    static readonly instances = [] as NativeInput[];

    readonly events: Registry<InputEvents>;

    readonly nativeHandle: audio.record.AudioRecorder;
    readonly nativeConsumer: audio.record.AudioConsumer;

    private state: InputState;
    private deviceId: string | undefined;

    private registeredFilters: (Filter & NativeFilter)[] = [];
    private filtered = false;

    constructor() {
        this.events = new Registry<InputEvents>();

        this.nativeHandle = audio.record.create_recorder();

        this.nativeConsumer = this.nativeHandle.create_consumer();
        this.nativeConsumer.toggle_rnnoise(settings.getValue(Settings.KEY_RNNOISE_FILTER));

        this.nativeConsumer.callback_ended = () => {
            this.filtered = true;
            this.events.fire("notify_voice_end");
        };
        this.nativeConsumer.callback_started = () => {
            this.filtered = false;
            this.events.fire("notify_voice_start");
        };

        this.state = InputState.PAUSED;
        NativeInput.instances.push(this);
    }

    destroy() {
        const index = NativeInput.instances.indexOf(this);
        if(index !== -1) {
            NativeInput.instances.splice(index, 1);
        }
    }

    private setState(newState: InputState) {
        if(this.state === newState) {
            return;
        }

        const oldState = this.state;
        this.state = newState;
        this.events.fire("notify_state_changed", { oldState, newState });
    }

    async start(): Promise<InputStartError | true> {
        if(this.state !== InputState.PAUSED) {
            logWarn(LogCategory.VOICE, tr("Input isn't paused"));
            return InputStartError.EBUSY;
        }

        this.setState(InputState.INITIALIZING);
        logTrace(LogCategory.AUDIO, tr("Starting input for device %o", this.deviceId));
        try {
            const state = await new Promise<audio.record.DeviceSetResult>(resolve => this.nativeHandle.set_device(this.deviceId, resolve));

            if(state !== "success") {
                if(state === "invalid-device") {
                    return InputStartError.EDEVICEUNKNOWN;
                } else if(state === undefined) {
                    throw tr("invalid set device result state");
                }

                /* FIXME! */
                throw state;
            }

            await new Promise((resolve, reject) => this.nativeHandle.start(result => {
                if(result === true) {
                    resolve();
                } else {
                    reject(typeof result === "string" ? result : tr("failed to start input"));
                }
            }));

            this.setState(InputState.RECORDING);
            return true;
        } finally {
            /* @ts-ignore Typescript isn't smart about awaits in try catch blocks */
            if(this.state === InputState.INITIALIZING) {
                this.setState(InputState.PAUSED);
            }
        }
    }

    async stop(): Promise<void> {
        if(this.state === InputState.PAUSED) {
            return;
        }

        this.nativeHandle.stop();
        this.setState(InputState.PAUSED);

        if(this.filtered) {
            this.filtered = false;
            this.events.fire("notify_voice_end");
        }
    }

    async setDeviceId(device: string | undefined): Promise<void> {
        if(this.deviceId === device) {
            return;
        }

        try {
            await this.stop();
        } catch (error) {
            logWarn(LogCategory.GENERAL, tr("Failed to stop microphone recording after device change: %o"), error);
        }

        const oldDeviceId = this.deviceId;
        this.deviceId = device;
        this.events.fire("notify_device_changed", { oldDeviceId, newDeviceId: device });
    }

    currentDeviceId(): string | undefined {
        return this.deviceId;
    }

    isFiltered(): boolean {
        return this.filtered;
    }

    removeFilter(filter: Filter) {
        const index = this.registeredFilters.indexOf(filter as any);
        if(index === -1) {
            return;
        }

        const [ registeredFilter ] = this.registeredFilters.splice(index, 1);
        registeredFilter.finalize();
    }

    createFilter<T extends FilterType>(type: T, priority: number): FilterTypeClass<T> {
        let filter;
        switch (type) {
            case FilterType.STATE:
                filter = new NStateFilter(this, priority);
                break;

            case FilterType.THRESHOLD:
                filter = new NThresholdFilter(this, priority);
                break;

            case FilterType.VOICE_LEVEL:
                filter = new NVoiceLevelFilter(this, priority);
                break;
        }

        this.registeredFilters.push(filter);
        return filter;
    }

    supportsFilter(type: FilterType): boolean {
        switch (type) {
            case FilterType.VOICE_LEVEL:
            case FilterType.THRESHOLD:
            case FilterType.STATE:
                return true;

            default:
                return false;
        }
    }

    currentState(): InputState {
        return this.state;
    }

    currentConsumer(): InputConsumer | undefined {
        return {
            type: InputConsumerType.NATIVE
        };
    }

    getNativeConsumer() : audio.record.AudioConsumer {
        return this.nativeConsumer;
    }

    async setConsumer(consumer: InputConsumer): Promise<void> {
        if(typeof(consumer) !== "undefined") {
            throw "we only support native consumers!"; // TODO: May create a general wrapper?
        }

        return;
    }

    setVolume(volume: number) {
        this.nativeHandle.set_volume(volume);
    }

    getVolume(): number {
        return this.nativeHandle.get_volume();
    }

    getFilterMode(): FilterMode {
        const mode = this.nativeConsumer.get_filter_mode();
        switch (mode) {
            case NativeFilterMode.Block:
                return FilterMode.Block;

            case NativeFilterMode.Bypass:
                return FilterMode.Bypass;

            case NativeFilterMode.Filter:
            default:
                return FilterMode.Filter;
        }
    }

    setFilterMode(mode: FilterMode) {
        let nativeMode: NativeFilterMode;
        switch (mode) {
            case FilterMode.Filter:
                nativeMode = NativeFilterMode.Filter;
                break;

            case FilterMode.Bypass:
                nativeMode = NativeFilterMode.Bypass;
                break;

            case FilterMode.Block:
                nativeMode = NativeFilterMode.Block;
                break;
        }

        if(this.nativeConsumer.get_filter_mode() === nativeMode) {
            return;
        }

        const oldMode = this.getFilterMode();
        this.nativeConsumer.set_filter_mode(nativeMode);
        this.events.fire("notify_filter_mode_changed", { oldMode, newMode: mode });
    }
}

export class NativeLevelMeter implements LevelMeter {
    static readonly instances: NativeLevelMeter[] = [];
    readonly targetDevice: IDevice;

    public nativeRecorder: audio.record.AudioRecorder;
    public nativeConsumer: audio.record.AudioConsumer;

    private callback: (num: number) => any;
    private nativeFilter: audio.record.ThresholdConsumeFilter;

    constructor(device: IDevice) {
        this.targetDevice = device;
    }

    async initialize() {
        try {
            this.nativeRecorder = audio.record.create_recorder();
            this.nativeConsumer = this.nativeRecorder.create_consumer();

            this.nativeConsumer.toggle_rnnoise(settings.getValue(Settings.KEY_RNNOISE_FILTER));

            this.nativeFilter = this.nativeConsumer.create_filter_threshold(.5);
            this.nativeFilter.set_attack_smooth(.75);
            this.nativeFilter.set_release_smooth(.75);

            await new Promise(resolve => this.nativeRecorder.set_device(this.targetDevice.deviceId, resolve));
            await new Promise((resolve, reject) => {
                this.nativeRecorder.start(flag => {
                    if (typeof flag === "boolean" && flag)
                        resolve();
                    else
                        reject(typeof flag === "string" ? flag : "failed to start");
                });
            });
        } catch (error) {
            if (typeof (error) === "string") {
                throw error;
            }

            logWarn(LogCategory.AUDIO, tr("Failed to initialize level meter for device %o: %o"), this.targetDevice, error);
            throw "initialize failed (lookup console)";
        }

        /* references this variable, needs a destroy() call, else memory leak */
        this.nativeFilter.set_analyze_filter(value => {
            if(this.callback) this.callback(value);
        });

        NativeLevelMeter.instances.push(this);
    }

    destroy() {
        const index = NativeLevelMeter.instances.indexOf(this);
        if(index !== -1) {
            NativeLevelMeter.instances.splice(index, 1);
        }

        if (this.nativeFilter) {
            this.nativeFilter.set_analyze_filter(undefined);
            this.nativeConsumer.unregister_filter(this.nativeFilter);
        }

        if (this.nativeConsumer) {
            this.nativeRecorder.delete_consumer(this.nativeConsumer);
        }

        if(this.nativeRecorder) {
            this.nativeRecorder.stop();
        }
        this.nativeRecorder = undefined;
        this.nativeConsumer = undefined;
        this.nativeFilter = undefined;
    }

    getDevice(): IDevice {
        return this.targetDevice;
    }

    setObserver(callback: (value: number) => any) {
        this.callback = callback;
    }
}