4chan browser

Button in catalog that shows all the images in all posts.

Aby zainstalować ten skrypt, wymagana jest instalacje jednego z następujących rozszerzeń: Tampermonkey, Greasemonkey lub Violentmonkey.

You will need to install an extension such as Tampermonkey to install this script.

Aby zainstalować ten skrypt, wymagana jest instalacje jednego z następujących rozszerzeń: Tampermonkey, Violentmonkey.

Aby zainstalować ten skrypt, wymagana będzie instalacja rozszerzenia Tampermonkey lub Userscripts.

You will need to install an extension such as Tampermonkey to install this script.

Aby zainstalować ten skrypt, musisz zainstalować rozszerzenie menedżera skryptów użytkownika.

(Mam już menedżera skryptów użytkownika, pozwól mi to zainstalować!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

Będziesz musiał zainstalować rozszerzenie menedżera stylów użytkownika, aby zainstalować ten styl.

Będziesz musiał zainstalować rozszerzenie menedżera stylów użytkownika, aby zainstalować ten styl.

Musisz zainstalować rozszerzenie menedżera stylów użytkownika, aby zainstalować ten styl.

(Mam już menedżera stylów użytkownika, pozwól mi to zainstalować!)

// ==UserScript==
// @name        4chan browser
// @namespace   e343367e7d795211da74d4a886e28f9c
// @description Button in catalog that shows all the images in all posts.
// @version     1.0.1
// @include     http://boards.4chan.org/*/catalog
// @include     https://boards.4chan.org/*/catalog
// @grant       none
// ==/UserScript==

(function () {
    
    const width = 200;
    const height = 200;
    const queries = {
        thread: '.thread',
        subject: '.teaser',
        image: '.fileThumb'
    };
    
    const button = document.createElement('button');
    button.innerHTML = 'Browse images';
    document.body.insertBefore(button, document.body.firstChild);
    button.addEventListener('click', () => {
        const window = open();
        const document = window.document;
        
        document.body.style.paddingTop = '20px';
        document.body.style.background = '#F1F1F1';
        
        navigation(window, document, threads(document));
    });
    
    function threads(newDocument) {
        const play = makePlay(newDocument);
        const tags = Array.from(document.querySelectorAll(queries.thread));
        return tags.map(tag => new Thread(newDocument, tag, play));
    }
    
    class Thread {
        constructor(document, tag, play) {
            let subject = tag.querySelector(queries.subject);
            if (subject) {
                subject = subject.innerHTML;
            } else {
                subject = 'Thread';
            }
            
            const a = document.createElement('a');
            a.href = tag.querySelector('a').href;
            a.innerHTML = subject;
            const p = document.createElement('p');
            p.appendChild(a);
            const loading = document.createTextNode('Loading');
            this.div = document.createElement('div');
            this.div.appendChild(p);
            this.div.appendChild(loading);
            
            this.request = new Promise((resolve, reject) => {
                const request = new XMLHttpRequest();
                request.open('GET', a.href);
                request.responseType = 'document';
                request.addEventListener('load', () => {
                    this.div.removeChild(loading);
                    
                    let images = queries.image;
                    images = request.response.querySelectorAll(images);
                    images = Array.from(images);
                    images = images.filter(image => image.href);
                    
                    this.thumbnails = images.map(image => {
                        return new Thumbnail(document, image, this.div, play);
                    });
                    
                    resolve();
                });
                request.send();
            });
        }
        
        load() {
            this.request.then(() => {
                for (let thumbnail of this.thumbnails) {
                    thumbnail.load();
                }
            });
        }
    }
    
    class Thumbnail {
        constructor(document, image, container, play) {
            this.image = image;
            
            this.img = document.createElement('img');
            this.img.style.display = 'block';
            this.img.style.margin = 'auto';
            this.img.addEventListener('error', () => {
                container.removeChild(this.div);
            });
            this.img.addEventListener('load', () => {
                if (this.img.naturalWidth > this.img.naturalHeight) {
                    this.img.width = width;
                } else {
                    this.img.height = height;
                }
            });
            
            const a = document.createElement('a');
            a.style.display = 'block';
            a.style.position = 'relative';
            a.href = image.href;
            a.target = '_blank';
            a.appendChild(this.img);

            this.div = document.createElement('div');
            this.div.style.width = width + 'px';
            this.div.style.height = height + 'px';
            this.div.style.padding = '10px';
            this.div.style.margin = '10px';
            this.div.style.borderRadius = '4px';
            this.div.style.display = 'inline-block';
            this.div.style.background = 'white';
            this.div.style.border = '1px solid #D8D8D8';
            this.div.appendChild(a);

            if (image.href.match(/.webm/)) {
                const canvas = document.createElement('canvas');
                canvas.width = width;
                canvas.height = height;
                canvas.style.position = 'absolute';
                canvas.style.top = '0px';
                canvas.getContext('2d').drawImage(play, 0, 0);
                a.appendChild(canvas);
            }
            
            container.appendChild(this.div);
        }
        
        load() {
            this.img.src = this.image.querySelector('img').src;
        }
    }
    
    function navigation(window, document, threads) {
        let i = 0;
        
        const next = document.createElement('button');
        next.innerHTML = 'next';
        next.style.position = 'fixed';
        next.style.right = '0px';
        next.style.top = '0px';
        next.style.zIndex = '1';
        next.addEventListener('click', function () {
            if (i == 0) {
                document.body.appendChild(previous);
            }

            document.body.removeChild(threads[i].div);
            i += 1;
            document.body.appendChild(threads[i].div);
            threads[i].load();

            if (i == threads.length - 1) {
                document.body.removeChild(next);
            }

            window.scrollTo(0, 0);
        });
        
        const previous = document.createElement('button');
        previous.innerHTML = 'previous';
        previous.style.position = 'fixed';
        previous.style.left = '0px';
        previous.style.top = '0px';
        previous.style.zIndex = '1';
        previous.addEventListener('click', function () {
            if (i == threads.length - 1) {
                document.body.appendChild(next);
            }

            document.body.removeChild(threads[i].div);
            i -= 1;
            document.body.appendChild(threads[i].div);
            threads[i].load();

            if (i == 0) {
                document.body.removeChild(previous);
            }

            window.scrollTo(0, 0);
        });
        
        document.body.appendChild(threads[i].div);
        document.body.appendChild(next);
        threads[i].load();
        
        window.addEventListener('keydown', function (event) {
            if (event.keyCode == 37 && i > 0) {
                previous.click();
            }

            if (event.keyCode == 39 && i < threads.length - 1) {
                next.click();
            }
        });
    }
    
    function makePlay(document) {
        const canvas = document.createElement('canvas');
        canvas.width = width;
        canvas.height = height;

        const context = canvas.getContext('2d');
        context.fillStyle = 'hsla(0, 0%, 80%, 0.25)';
        context.strokeStyle = 'hsla(0, 0%, 100%, 0.5)';
        context.lineWidth = 2;
        context.moveTo(width / 3, height / 3);
        context.lineTo(width / 3 * 2, height / 2);
        context.lineTo(width / 3, height / 3 * 2);
        context.closePath();
        context.fill();
        context.stroke();

        return canvas;
    }
})();