import Backbone from 'backbone';
import QrCode from 'jsqrcode';
import { Shortcuts } from 'comp/app/shortcuts';
import { Alerts } from 'comp/ui/alerts';
import { Otp } from 'util/data/otp';
import { Features } from 'util/features';
import { Locale } from 'util/locale';
import { Logger } from 'util/logger';

const logger = new Logger('otp-qr-reader');

const OtpQrReader = {
    alert: null,

    fileInput: null,

    read() {
        let screenshotKey = Shortcuts.screenshotToClipboardShortcut();
        if (screenshotKey) {
            screenshotKey = Locale.detSetupOtpAlertBodyWith.replace(
                '{}',
                '<code>' + screenshotKey + '</code>'
            );
        }
        const pasteKey = Features.isMobile
            ? ''
            : Locale.detSetupOtpAlertBodyWith.replace(
                  '{}',
                  '<code>' + Shortcuts.actionShortcutSymbol() + 'V</code>'
              );
        OtpQrReader.startListenClipoard();
        const buttons = [
            { result: 'manually', title: Locale.detSetupOtpManualButton, silent: true },
            Alerts.buttons.cancel
        ];
        if (Features.isMobile) {
            buttons.unshift({ result: 'select', title: Locale.detSetupOtpScanButton });
        }
        const line3 = Features.isMobile
            ? Locale.detSetupOtpAlertBody3Mobile
            : Locale.detSetupOtpAlertBody3.replace('{}', pasteKey || '');
        OtpQrReader.alert = Alerts.alert({
            icon: 'qrcode',
            header: Locale.detSetupOtpAlert,
            body: [
                Locale.detSetupOtpAlertBody,
                Locale.detSetupOtpAlertBody1,
                Locale.detSetupOtpAlertBody2.replace('{}', screenshotKey || ''),
                line3,
                Locale.detSetupOtpAlertBody4
            ].join('<br/>'),
            esc: '',
            click: '',
            enter: '',
            buttons,
            complete(res) {
                OtpQrReader.alert = null;
                OtpQrReader.stopListenClipboard();
                if (res === 'select') {
                    OtpQrReader.selectFile();
                } else if (res === 'manually') {
                    OtpQrReader.enterManually();
                }
            }
        });
    },

    selectFile() {
        if (!OtpQrReader.fileInput) {
            const input = document.createElement('input');
            input.setAttribute('type', 'file');
            input.setAttribute('capture', 'camera');
            input.setAttribute('accept', 'image/*');
            input.setAttribute('class', 'hide-by-pos');
            OtpQrReader.fileInput = input;
            OtpQrReader.fileInput.onchange = OtpQrReader.fileSelected;
        }
        OtpQrReader.fileInput.click();
    },

    fileSelected() {
        const file = OtpQrReader.fileInput.files[0];
        if (!file || file.type.indexOf('image') < 0) {
            return;
        }
        OtpQrReader.readFile(file);
    },

    startListenClipoard() {
        document.addEventListener('paste', OtpQrReader.pasteEvent);
    },

    stopListenClipboard() {
        document.removeEventListener('paste', OtpQrReader.pasteEvent);
    },

    pasteEvent(e) {
        const item = _.find(
            e.clipboardData.items,
            item => item.kind === 'file' && item.type.indexOf('image') !== -1
        );
        if (!item) {
            logger.debug('Paste without file');
            return;
        }
        logger.info('Reading pasted image', item.type);
        if (OtpQrReader.alert) {
            OtpQrReader.alert.change({
                header: Locale.detOtpImageReading
            });
        }
        OtpQrReader.readFile(item.getAsFile());
    },

    readFile(file) {
        const reader = new FileReader();
        reader.onload = function() {
            logger.debug('Image data loaded');
            OtpQrReader.readQr(reader.result);
        };
        reader.readAsDataURL(file);
    },

    readQr(imageData) {
        const image = new Image();
        image.onload = function() {
            logger.debug('Image format loaded');
            try {
                const ts = logger.ts();
                const url = new QrCode(image).decode();
                logger.info('QR code read', logger.ts(ts));
                OtpQrReader.removeAlert();
                try {
                    const otp = Otp.parseUrl(url);
                    OtpQrReader.trigger('qr-read', otp);
                } catch (err) {
                    logger.error('Error parsing QR code', err);
                    Alerts.error({
                        header: Locale.detOtpQrWrong,
                        body:
                            Locale.detOtpQrWrongBody +
                            '<pre class="modal__pre">' +
                            _.escape(err.toString()) +
                            '</pre>'
                    });
                }
            } catch (e) {
                logger.error('Error reading QR code', e);
                OtpQrReader.removeAlert();
                Alerts.error({
                    header: Locale.detOtpQrError,
                    body: Locale.detOtpQrErrorBody
                });
            }
        };
        image.onerror = function() {
            logger.debug('Image load error');
            OtpQrReader.removeAlert();
            Alerts.error({
                header: Locale.detOtpImageError,
                body: Locale.detOtpImageErrorBody
            });
        };
        image.src = imageData;
    },

    enterManually() {
        OtpQrReader.trigger('enter-manually');
    },

    removeAlert() {
        if (OtpQrReader.alert) {
            OtpQrReader.alert.closeImmediate();
        }
    }
};

_.extend(OtpQrReader, Backbone.Events);

export { OtpQrReader };