import { TapeData } from '../types';
import Apple2IO from '../apple2io';
import { debug } from '../util';

export const TAPE_TYPES = ['wav', 'aiff', 'aif', 'mp3', 'm4a'] as const;

export default class Tape {
    constructor(private readonly io: Apple2IO) {}

    public doLoadLocalTape(file: File, done?: () => void) {
        const kHz = this.io.getKHz();

        // Audio Buffer Source
        let context: AudioContext;
        if (AudioContext) {
            context = new AudioContext();
        } else {
            window.alert('Not supported by your browser');
            done && done();
            return;
        }

        const fileReader = new FileReader();
        fileReader.onload = (ev: ProgressEvent) => {
            const target: FileReader = ev.target as FileReader;
            const result: ArrayBuffer = target.result as ArrayBuffer;
            context.decodeAudioData(result).then(
                (buffer) => {
                    const buf: TapeData = [];
                    const data = buffer.getChannelData(0);
                    let datum = data[0];
                    let old = datum > 0.0,
                        current;
                    let last = 0;
                    let delta: number;
                    debug(`Sample Count: ${data.length}`);
                    debug(`Sample rate: ${buffer.sampleRate}`);
                    for (let idx = 1; idx < data.length; idx++) {
                        datum = data[idx];
                        if (datum > 0.1 || datum < -0.1) {
                            current = datum > 0.0;
                            if (current !== old) {
                                delta = idx - last;
                                if (delta > 2000000) {
                                    delta = 2000000;
                                }
                                let ival = (delta / buffer.sampleRate) * 1000;
                                if (ival >= 0.55 && ival < 0.75) {
                                    ival = 0.65; // Header
                                } else if (ival >= 0.175 && ival < 0.225) {
                                    ival = 0.2; // sync 1
                                } else if (ival >= 0.225 && ival < 0.275) {
                                    ival = 0.25; // 0 / sync 2
                                } else if (ival >= 0.45 && ival < 0.55) {
                                    ival = 0.5; // 1
                                } else {
                                    // debug(idx + ' ' + buf.length + ' ' + ival);
                                }
                                buf.push([ival * kHz, current]);
                                old = current;
                                last = idx;
                            }
                        }
                    }
                    this.io.setTape(buf);
                    if (done) {
                        done();
                    }
                },
                (error: Error) => {
                    window.alert(error.message);
                }
            );
        };
        fileReader.readAsArrayBuffer(file);
    }
}