PairDrop/client/scripts/ui.js

const $ = query => document.getElementById(query);
const $$ = query => document.body.querySelector(query);
const isURL = text => /^((https?:\/\/|www)[^\s]+)/g.test(text.toLowerCase());
window.isDownloadSupported = (typeof document.createElement('a').download !== 'undefined');
window.isProductionEnvironment = !window.location.host.startsWith('localhost');
window.iOS = /iPad|iPhone|iPod/.test(navigator.userAgent) && !window.MSStream;

class PeersUI {

    constructor() {
        Events.on('peer-joined', e => this._onPeerJoined(e.detail));
        Events.on('peer-left', e => this._onPeerLeft(e.detail));
        Events.on('peers', e => this._onPeers(e.detail));
        Events.on('file-progress', e => this._onFileProgress(e.detail));        
        Events.on('paste', e => this._onPaste(e));
    }

    _onPeerJoined(peer) {
        if (document.getElementById(peer.id)) return;
        const peerUI = new PeerUI(peer);
        $$('x-peers').appendChild(peerUI.$el);
    }

    _onPeers(peers) {
        this._clearPeers();
        peers.forEach(peer => this._onPeerJoined(peer));
    }

    _onPeerLeft(peerId) {
        const $peer = $(peerId);
        if (!$peer) return;
        $peer.remove();
    }

    _onFileProgress(progress) {
        const peerId = progress.sender || progress.recipient;
        const $peer = $(peerId);
        if (!$peer) return;
        $peer.ui.setProgress(progress.progress);
    }

    _clearPeers() {
        const $peers = $$('x-peers').innerHTML = '';
    }   
    
    _onPaste(e) {        
        const files = e.clipboardData.files || e.clipboardData.items
            .filter(i => i.type.indexOf('image') > -1)
            .map(i => i.getAsFile());
        const peers = document.querySelectorAll('x-peer');
        // send the pasted image content to the only peer if there is one
        // otherwise, select the peer somehow by notifying the client that
        // "image data has been pasted, click the client to which to send it"
        // not implemented
        if (files.length > 0 && peers.length === 1) {
            Events.fire('files-selected', {
                files: files,
                to: $$('x-peer').id
            });
        }
    }
}

class PeerUI {

    html() {
        return `   
            <label class="column center">
                <input type="file" multiple>
                <x-icon shadow="1">
                    <svg class="icon"><use xlink:href="#"/></svg>
                </x-icon>
                <div class="progress">
                  <div class="circle"></div>
                  <div class="circle right"></div>
                </div>
                <div class="name font-subheading"></div>
                <div class="status font-body2"></div>
            </label>`
    }

    constructor(peer) {
        this._peer = peer;
        this._initDom();
        this._bindListeners(this.$el);
    }

    _initDom() {
        const el = document.createElement('x-peer');
        el.id = this._peer.id;
        el.innerHTML = this.html();
        el.ui = this;
        el.querySelector('svg use').setAttribute('xlink:href', this._icon());
        el.querySelector('.name').textContent = this._name();
        this.$el = el;
        this.$progress = el.querySelector('.progress');
    }

    _bindListeners(el) {
        el.querySelector('input').addEventListener('change', e => this._onFilesSelected(e));
        el.addEventListener('drop', e => this._onDrop(e));
        el.addEventListener('dragend', e => this._onDragEnd(e));
        el.addEventListener('dragleave', e => this._onDragEnd(e));
        el.addEventListener('dragover', e => this._onDragOver(e));
        el.addEventListener('contextmenu', e => this._onRightClick(e));
        el.addEventListener('touchstart', e => this._onTouchStart(e));
        el.addEventListener('touchend', e => this._onTouchEnd(e));
        // prevent browser's default file drop behavior
        Events.on('dragover', e => e.preventDefault());
        Events.on('drop', e => e.preventDefault());
    }

    _name() {
        return this._peer.name.displayName;
    }

    _icon() {
        const device = this._peer.name.device || this._peer.name;
        if (device.type === 'mobile') {
            return '#phone-iphone';
        }
        if (device.type === 'tablet') {
            return '#tablet-mac';
        }
        return '#desktop-mac';
    }

    _onFilesSelected(e) {
        const $input = e.target;
        const files = $input.files;
        Events.fire('files-selected', {
            files: files,
            to: this._peer.id
        });
        $input.value = null; // reset input
        this.setProgress(0.01);
    }

    setProgress(progress) {
        if (progress > 0) {
            this.$el.setAttribute('transfer', '1');
        }
        if (progress > 0.5) {
            this.$progress.classList.add('over50');
        } else {
            this.$progress.classList.remove('over50');
        }
        const degrees = `rotate(${360 * progress}deg)`;
        this.$progress.style.setProperty('--progress', degrees);
        if (progress >= 1) {
            this.setProgress(0);
            this.$el.removeAttribute('transfer');
        }
    }

    _onDrop(e) {
        e.preventDefault();
        const files = e.dataTransfer.files;
        Events.fire('files-selected', {
            files: files,
            to: this._peer.id
        });
        this._onDragEnd();
    }

    _onDragOver() {
        this.$el.setAttribute('drop', 1);
    }

    _onDragEnd() {
        this.$el.removeAttribute('drop');
    }

    _onRightClick(e) {
        e.preventDefault();
        Events.fire('text-recipient', this._peer.id);
    }

    _onTouchStart(e) {
        this._touchStart = Date.now();
        this._touchTimer = setTimeout(_ => this._onTouchEnd(), 610);
    }

    _onTouchEnd(e) {
        if (Date.now() - this._touchStart < 500) {
            clearTimeout(this._touchTimer);
        } else { // this was a long tap
            if (e) e.preventDefault();
            Events.fire('text-recipient', this._peer.id);
        }
    }
}


class Dialog {
    constructor(id) {
        this.$el = $(id);
        this.$el.querySelectorAll('[close]').forEach(el => el.addEventListener('click', e => this.hide()))
        this.$autoFocus = this.$el.querySelector('[autofocus]');
    }

    show() {
        this.$el.setAttribute('show', 1);
        if (this.$autoFocus) this.$autoFocus.focus();
    }

    hide() {
        this.$el.removeAttribute('show');
        document.activeElement.blur();
        window.blur();
    }
}

class ReceiveDialog extends Dialog {

    constructor() {
        super('receiveDialog');
        Events.on('file-received', e => {
            this._nextFile(e.detail);
            window.blop.play();
        });
        this._filesQueue = [];
    }

    _nextFile(nextFile) {
        if (nextFile) this._filesQueue.push(nextFile);
        if (this._busy) return;
        this._busy = true;
        const file = this._filesQueue.shift();
        this._displayFile(file);
    }

    _dequeueFile() {
        if (!this._filesQueue.length) { // nothing to do
            this._busy = false;
            return;
        }
        // dequeue next file
        setTimeout(_ => {
            this._busy = false;
            this._nextFile();
        }, 300);
    }

    _displayFile(file) {
        const $a = this.$el.querySelector('#download');
        const url = URL.createObjectURL(file.blob);
        $a.href = url;
        $a.download = file.name;

        this.$el.querySelector('#fileName').textContent = file.name;
        this.$el.querySelector('#fileSize').textContent = this._formatFileSize(file.size);
        this.show();

        if (window.isDownloadSupported) return;
        // fallback for iOS
        $a.target = '_blank';
        const reader = new FileReader();
        reader.onload = e => $a.href = reader.result;
        reader.readAsDataURL(file.blob);
    }

    _formatFileSize(bytes) {
        if (bytes >= 1e9) {
            return (Math.round(bytes / 1e8) / 10) + ' GB';
        } else if (bytes >= 1e6) {
            return (Math.round(bytes / 1e5) / 10) + ' MB';
        } else if (bytes > 1000) {
            return Math.round(bytes / 1000) + ' KB';
        } else {
            return bytes + ' Bytes';
        }
    }

    hide() {
        super.hide();
        this._dequeueFile();
    }
}


class SendTextDialog extends Dialog {
    constructor() {
        super('sendTextDialog');
        Events.on('text-recipient', e => this._onRecipient(e.detail))
        this.$text = this.$el.querySelector('#textInput');
        const button = this.$el.querySelector('form');
        button.addEventListener('submit', e => this._send(e));
    }

    _onRecipient(recipient) {
        this._recipient = recipient;
        this._handleShareTargetText();
        this.show();
        this.$text.setSelectionRange(0, this.$text.value.length)
    }

    _handleShareTargetText() {
        if (!window.shareTargetText) return;
        this.$text.value = window.shareTargetText;
        window.shareTargetText = '';
    }

    _send(e) {
        e.preventDefault();
        Events.fire('send-text', {
            to: this._recipient,
            text: this.$text.value
        });
    }
}

class ReceiveTextDialog extends Dialog {
    constructor() {
        super('receiveTextDialog');
        Events.on('text-received', e => this._onText(e.detail))
        this.$text = this.$el.querySelector('#text');
        const $copy = this.$el.querySelector('#copy');
        copy.addEventListener('click', _ => this._onCopy());
    }

    _onText(e) {
        this.$text.innerHTML = '';
        const text = e.text;
        if (isURL(text)) {
            const $a = document.createElement('a');
            $a.href = text;
            $a.target = '_blank';
            $a.textContent = text;
            this.$text.appendChild($a);
        } else {
            this.$text.textContent = text;
        }
        this.show();
        window.blop.play();
    }

    _onCopy() {
        if (!document.copy(this.$text.textContent)) return;
        Events.fire('notify-user', 'Copied to clipboard');
    }
}

class Toast extends Dialog {
    constructor() {
        super('toast');
        Events.on('notify-user', e => this._onNotfiy(e.detail));
    }

    _onNotfiy(message) {
        this.$el.textContent = message;
        this.show();
        setTimeout(_ => this.hide(), 3000);
    }
}


class Notifications {

    constructor() {
        // Check if the browser supports notifications
        if (!('Notification' in window)) return;

        // Check whether notification permissions have already been granted
        if (Notification.permission !== 'granted') {
            this.$button = $('notification');
            this.$button.removeAttribute('hidden');
            this.$button.addEventListener('click', e => this._requestPermission());
        }
        Events.on('text-received', e => this._messageNotification(e.detail.text));
        Events.on('file-received', e => this._downloadNotification(e.detail.name));
    }

    _requestPermission() {
        Notification.requestPermission(permission => {
            if (permission !== 'granted') {
                Events.fire('notify-user', Notifications.PERMISSION_ERROR || 'Error');
                return;
            }
            this._notify('Even more snappy sharing!');
            this.$button.setAttribute('hidden', 1);
        });
    }

    _notify(message, body, closeTimeout = 20000) {
        const config = {
            body: body,
            icon: '/images/logo_transparent_128x128.png',
        }
        let notification;
        try {
            notification = new Notification(message, config);
        } catch (e) {
            // Android doesn't support "new Notification" if service worker is installed
            if (!serviceWorker || !serviceWorker.showNotification) return;
            notification = serviceWorker.showNotification(message, config);
        }

        // Notification is persistent on Android. We have to close it manually
        if (closeTimeout) {
            setTimeout(_ => notification.close(), closeTimeout);
        }

        return notification;
    }

    _messageNotification(message) {
        if (isURL(message)) {
            const notification = this._notify(message, 'Click to open link');
            this._bind(notification, e => window.open(message, '_blank', null, true));
        } else {
            const notification = this._notify(message, 'Click to copy text');
            this._bind(notification, e => this._copyText(message, notification));
        }
    }

    _downloadNotification(message) {
        const notification = this._notify(message, 'Click to download');
        if (!window.isDownloadSupported) return;
        this._bind(notification, e => this._download(notification));
    }

    _download(notification) {
        document.querySelector('x-dialog [download]').click();
        notification.close();
    }

    _copyText(message, notification) {
        notification.close();
        if (!document.copy(message)) return;
        this._notify('Copied text to clipboard');
    }

    _bind(notification, handler) {
        if (notification.then) {
            notification.then(e => serviceWorker.getNotifications().then(notifications => {
                serviceWorker.addEventListener('notificationclick', handler);
            }));
        } else {
            notification.onclick = handler;
        }
    }
}


class NetworkStatusUI {

    constructor() {
        window.addEventListener('offline', e => this._showOfflineMessage(), false);
        window.addEventListener('online', e => this._showOnlineMessage(), false);
        if (!navigator.onLine) this._showOfflineMessage();
    }

    _showOfflineMessage() {
        Events.fire('notify-user', 'You are offline');
    }

    _showOnlineMessage() {
        Events.fire('notify-user', 'You are back online');
    }
}

class WebShareTargetUI {
    constructor() {
        const parsedUrl = new URL(window.location);
        const title = parsedUrl.searchParams.get('title');
        const text = parsedUrl.searchParams.get('text');
        const url = parsedUrl.searchParams.get('url');

        let shareTargetText = title ? title : '';
        shareTargetText += text ? shareTargetText ? ' ' + text : text : '';
        shareTargetText += url ? shareTargetText ? ' ' + url : url : '';
        if (!shareTargetText) return;
        window.shareTargetText = shareTargetText;
        history.pushState({}, 'URL Rewrite', '/');
        console.log('Shared Target Text:', '"' + shareTargetText + '"');
    }
}


class Snapdrop {
    constructor() {
        const server = new ServerConnection();
        const peers = new PeersManager(server);
        const peersUI = new PeersUI();
        Events.on('load', e => {
            const receiveDialog = new ReceiveDialog();
            const sendTextDialog = new SendTextDialog();
            const receiveTextDialog = new ReceiveTextDialog();
            const toast = new Toast();
            const notifications = new Notifications();
            const networkStatusUI = new NetworkStatusUI();
            const webShareTargetUI = new WebShareTargetUI();
        });

        // set display name
        Events.on('displayName', e => {
            $("displayName").textContent = "You are known as " + e.detail.message;
        });
    }
}

const snapdrop = new Snapdrop();

document.copy = text => {
    // A <span> contains the text to copy
    const span = document.createElement('span');
    span.textContent = text;
    span.style.whiteSpace = 'pre'; // Preserve consecutive spaces and newlines

    // Paint the span outside the viewport
    span.style.position = 'absolute';
    span.style.left = '-9999px';
    span.style.top = '-9999px';

    const win = window;
    const selection = win.getSelection();
    win.document.body.appendChild(span);

    const range = win.document.createRange();
    selection.removeAllRanges();
    range.selectNode(span);
    selection.addRange(range);

    let success = false;
    try {
        success = win.document.execCommand('copy');
    } catch (err) {}

    selection.removeAllRanges();
    span.remove();

    return success;
}


if ('serviceWorker' in navigator) {
    navigator.serviceWorker.register('/service-worker.js')
        .then(serviceWorker => {
            console.log('Service Worker registered');
            window.serviceWorker = serviceWorker
        });
}

window.addEventListener('beforeinstallprompt', e => {
    if (window.matchMedia('(display-mode: standalone)').matches) {
        // don't display install banner when installed
        return e.preventDefault();
    } else {
        const btn = document.querySelector('#install')
        btn.hidden = false;
        btn.onclick = _ => e.prompt();
        return e.preventDefault();
    }
});

// Background Animation
Events.on('load', () => {
    var requestAnimFrame = (function() {
        return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || window.oRequestAnimationFrame || window.msRequestAnimationFrame ||
            function(callback) {
                window.setTimeout(callback, 1000 / 60);
            };
    })();
    var c = document.createElement('canvas');
    document.body.appendChild(c);
    var style = c.style;
    style.width = '100%';
    style.position = 'absolute';
    style.zIndex = -1;
    style.top = 0;
    style.left = 0;
    var ctx = c.getContext('2d');
    var x0, y0, w, h, dw;

    function init() {
        w = window.innerWidth;
        h = window.innerHeight;
        c.width = w;
        c.height = h;
        var offset = h > 380 ? 100 : 65;
        x0 = w / 2;
        y0 = h - offset;
        dw = Math.max(w, h, 1000) / 13;
        drawCircles();
    }
    window.onresize = init;

    function drawCicrle(radius) {
        ctx.beginPath();
        var color = Math.round(255 * (1 - radius / Math.max(w, h)));
        ctx.strokeStyle = 'rgba(' + color + ',' + color + ',' + color + ',0.1)';
        ctx.arc(x0, y0, radius, 0, 2 * Math.PI);
        ctx.stroke();
        ctx.lineWidth = 2;
    }

    var step = 0;

    function drawCircles() {
        ctx.clearRect(0, 0, w, h);
        for (var i = 0; i < 8; i++) {
            drawCicrle(dw * i + step % dw);
        }
        step += 1;
    }

    var loading = true;

    function animate() {
        if (loading || step % dw < dw - 5) {
            requestAnimFrame(function() {
                drawCircles();
                animate();
            });
        }
    }
    window.animateBackground = function(l) {
        loading = l;
        animate();
    };
    init();
    animate();
    setTimeout(e => window.animateBackground(false), 3000);
});

Notifications.PERMISSION_ERROR = `
Notifications permission has been blocked 
as the user has dismissed the permission prompt several times. 
This can be reset in Page Info 
which can be accessed by clicking the lock icon next to the URL.`;

document.body.onclick = e => { // safari hack to fix audio 
    document.body.onclick = null;
    if (!(/.*Version.*Safari.*/.test(navigator.userAgent))) return;
    blop.play();
}