import { IConvolverNode, IConvolverOptions } from '../interfaces';
import { TAnyAudioBuffer, TAudioNodeRenderer, TContext, TConvolverNodeConstructorFactory, TNativeConvolverNode } from '../types';

const DEFAULT_OPTIONS = {
    buffer: null,
    channelCount: 2,
    channelCountMode: 'clamped-max',
    channelInterpretation: 'speakers',
    disableNormalization: false
} as const;

export const createConvolverNodeConstructor: TConvolverNodeConstructorFactory = (
    audioNodeConstructor,
    createConvolverNodeRenderer,
    createNativeConvolverNode,
    getNativeContext,
    isNativeOfflineAudioContext,
    setAudioNodeTailTime
) => {
    return class ConvolverNode<T extends TContext> extends audioNodeConstructor<T> implements IConvolverNode<T> {
        private _isBufferNullified: boolean;

        private _nativeConvolverNode: TNativeConvolverNode;

        constructor(context: T, options?: Partial<IConvolverOptions>) {
            const nativeContext = getNativeContext(context);
            const mergedOptions = { ...DEFAULT_OPTIONS, ...options };
            const nativeConvolverNode = createNativeConvolverNode(nativeContext, mergedOptions);
            const isOffline = isNativeOfflineAudioContext(nativeContext);
            const convolverNodeRenderer = <TAudioNodeRenderer<T, this>>(isOffline ? createConvolverNodeRenderer() : null);

            super(context, false, nativeConvolverNode, convolverNodeRenderer);

            this._isBufferNullified = false;
            this._nativeConvolverNode = nativeConvolverNode;

            if (mergedOptions.buffer !== null) {
                setAudioNodeTailTime(this, mergedOptions.buffer.duration);
            }
        }

        get buffer(): null | TAnyAudioBuffer {
            if (this._isBufferNullified) {
                return null;
            }

            return this._nativeConvolverNode.buffer;
        }

        set buffer(value) {
            this._nativeConvolverNode.buffer = value;

            // Bug #115: Safari does not allow to set the buffer to null.
            if (value === null && this._nativeConvolverNode.buffer !== null) {
                const nativeContext = this._nativeConvolverNode.context;

                this._nativeConvolverNode.buffer = nativeContext.createBuffer(1, 1, nativeContext.sampleRate);
                this._isBufferNullified = true;

                setAudioNodeTailTime(this, 0);
            } else {
                this._isBufferNullified = false;

                setAudioNodeTailTime(this, this._nativeConvolverNode.buffer === null ? 0 : this._nativeConvolverNode.buffer.duration);
            }
        }

        get normalize(): boolean {
            return this._nativeConvolverNode.normalize;
        }

        set normalize(value) {
            this._nativeConvolverNode.normalize = value;
        }
    };
};