Danbooru Strip

Strip Danbooru images with your mouse

Versión del día 26/11/2024. Echa un vistazo a la versión más reciente.

Tendrás que instalar una extensión para tu navegador como Tampermonkey, Greasemonkey o Violentmonkey si quieres utilizar este script.

Necesitarás instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Userscripts para instalar este script.

Necesitará instalar una extensión como Tampermonkey para instalar este script.

Necesitarás instalar una extensión para administrar scripts de usuario si quieres instalar este script.

(Ya tengo un administrador de scripts de usuario, déjame instalarlo)

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión como Stylus para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

Necesitará instalar una extensión del gestor de estilos de usuario para instalar este estilo.

(Ya tengo un administrador de estilos de usuario, déjame instalarlo)

// ==UserScript==
// @name         Danbooru Strip
// @description  Strip Danbooru images with your mouse
// @version      0.1.3
// @namespace    https://github.com/andre-atgit/danbooru-strip/
// @match        *://danbooru.donmai.us/posts/*
// @license      MIT
// @run-at       document-idle
// ==/UserScript==

/* jshint esversion: 8 */

(function() {
    'use strict';

    const strip = { isLoaded: false };
    appendStripOnPageLoad();

    function appendStripOnPageLoad() {
        const parentNotice = document.getElementsByClassName('post-notice-parent');
        const childNotice = document.getElementsByClassName('post-notice-child');
        if (!parentNotice.length && !childNotice.length) return;

        const currentPost = document.getElementsByClassName('current-post');
        const intervalId = setInterval(() => {
            if (currentPost.length) {
                appendCss();
                appendStripTags();
                clearInterval(intervalId);
            }
        }, 100);
    }

    function appendCss() {
        const style = document.createElement('style');
        document.head.appendChild(style);
        style.innerHTML = `
        .strip-preview-tag {
            border-radius: 0px 0px 5px 5px;
            color: white;
            text-align: center;
        }

        .post-status-has-children .strip-preview-tag {
            background-color: var(--preview-has-children-color);
        }

        .post-status-has-parent .strip-preview-tag {
            background-color: var(--preview-has-parent-color);
        }

        #strip-canvas-container {
            position: relative;
            width: fit-content;
        }

        #strip-full-view-container {
            display: none;
            position: fixed;
            z-index: 1;
            left: 0;
            top: 0;
            width: 100%;
            height: 100%;
            overflow: auto;
            background-color: #0E0E0E;
        }

        #strip-canvas-container .fit {
            max-width: 100%;
            height: auto !important
        }

        #strip-full-view-container .fit {
            max-height: 100%;
            max-width: 100%;
            position: fixed !important;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
        }

        #strip-bottom-layer {
            position: absolute;
        }

        #strip-top-layer {
            position: absolute;
            z-index: 1;
        }

        #strip-cursor-layer {
            position: relative;
            z-index: 2;
        }`;
    }

    function appendStripTags() {
        const previewElements = document.getElementsByClassName('post-preview-container');
        if (!previewElements || previewElements.length < 2) return;

        for (const previewElement of previewElements) {
            const previewLinkElem = previewElement.getElementsByClassName('post-preview-link')[0];
            const apiLink = previewLinkElem.href.split('?')[0] + '.json';

            const p = document.createElement('p');
            p.classList.add('strip-preview-tag', 'cursor-pointer');
            previewElement.after(p);

            if (previewElement.parentElement.classList.contains('current-post')) {
                p.innerHTML = 'Current';
                strip.topLayerApiLink = apiLink;
            } else {
                p.innerHTML = '<a>Strip!</a>';
                p.onclick = (evt) => {
                    const currentlySelected = document.getElementById('strip-selected');
                    if (currentlySelected) currentlySelected.parentElement.innerHTML = '<a>Strip!</a>';
                    evt.currentTarget.innerHTML = '<span id="strip-selected">Selected</span>';

                    strip.bottomLayerApiLink = apiLink;
                    initCanvas();
                };
            }
        }
    }

    async function initCanvas() {
        if (strip.isLoaded) {
            await fetchData();
            loadImgs();
            return;
        }

        strip.isLoaded = true;
        strip.lineWidth = 100;
        strip.isDrawing = false;

        strip.undoHistory = [];
        strip.redoHistory = [];

        strip.prevX = null;
        strip.prevY = null;
        strip.currentX = null;
        strip.currentY = null;

        appendCanvas();
        appendOptions();
        await fetchData();
        loadImgs();
        addEvents();
        addHotkeys();
    }

    function appendCanvas() {
        const content = document.createElement('div');
        content.innerHTML = `
        <div id="strip-canvas-container">
            <canvas id="strip-bottom-layer" class="fit"></canvas>
            <canvas id="strip-top-layer" class="fit"></canvas>
            <canvas id="strip-cursor-layer" oncontextmenu="return false" onselectstart="return false" class="fit"> </canvas>
        </div>
        <div id="strip-full-view-container"></div>`;

        const containers = content.children;
        strip.canvasContainer = containers[0];
        strip.fullViewContainer = containers[1];
        strip.fullViewContainer.onmousedown = (evt) => (evt.target === strip.fullViewContainer) && toggleFullView();

        const canvases = content.getElementsByTagName('canvas');
        strip.bottomLayer = canvases[0];
        strip.topLayer = canvases[1];
        strip.cursorLayer = canvases[2];

        strip.bottomCtx = strip.bottomLayer.getContext('2d');
        strip.topCtx = strip.topLayer.getContext('2d');
        strip.cursorCtx = strip.cursorLayer.getContext('2d');

        const resizeNotice = document.getElementById('image-resize-notice');
        if (resizeNotice) resizeNotice.style.display = 'none';

        const image = document.getElementById('image');
        const imageSection = image.closest('section');
        for (const child of imageSection.children) {
            child.style.display = 'none';
        }

        imageSection.appendChild(strip.canvasContainer);
        imageSection.appendChild(strip.fullViewContainer);
    }

    function appendOptions() {
        const stripOptions = document.createElement('section');
        stripOptions.innerHTML = `
        <h2>Strip</h2>
        <ul>
            <li><a class="cursor-pointer">Toggle full view</a></li>
            <li><a class="cursor-pointer">Undo</a></li>
            <li><a class="cursor-pointer">Redo</a></li>
            <li><a class="cursor-pointer">Download strip</a></li>
            <li><a class="cursor-pointer">Brush width</a></li>
            <li><input type="range" min="1" max="400" value="100"></li>
        </ul>`;

        const options = stripOptions.getElementsByTagName('a');
        options[0].onclick = () => toggleFullView();
        options[1].onclick = () => undo();
        options[2].onclick = () => redo();
        options[3].onclick = () => download();

        strip.lineWidthInput = stripOptions.getElementsByTagName('input')[0];
        strip.lineWidthInput.onchange = (evt) => setLineWidth(Number(evt.target.value));

        const sidebar = document.getElementById('sidebar');
        sidebar.appendChild(stripOptions);
    }

    async function fetchData() {
        const topLayerRequest = fetch(strip.topLayerApiLink).then((res) => res.json());
        const bottomLayerRequest = fetch(strip.bottomLayerApiLink).then((res) => res.json());

        const [topLayerData, bottomLayerData] = await Promise.all([topLayerRequest, bottomLayerRequest]);
        const image = document.getElementById('image');

        const topVariant = topLayerData.media_asset.variants.find((variant) => variant.width === image.naturalWidth);
        const bottomVariant = bottomLayerData.media_asset.variants.find((variant) => variant.width === image.naturalWidth);

        strip.topLayerUrl = topVariant ? topVariant.url : topLayerData.file_url;
        strip.bottomLayerUrl = bottomVariant ? bottomVariant.url : bottomLayerData.file_url;
    }

    function loadImgs() {
        const topImg = new Image();
        const bottomImg = new Image();

        topImg.crossOrigin = 'anonymous';
        topImg.src = strip.topLayerUrl;

        bottomImg.crossOrigin = 'anonymous';
        bottomImg.src = strip.bottomLayerUrl;

        topImg.onload = () => {
            strip.topImage = topImg;
            if (strip.bottomImage) drawImgs();
        };

        bottomImg.onload = () => {
            strip.bottomImage = bottomImg;
            if (strip.topImage) drawImgs();
        };
    }

    function drawImgs() {
        const width = strip.cursorLayer.width = strip.bottomLayer.width = strip.topLayer.width = strip.topImage.width;
        const height = strip.cursorLayer.height = strip.bottomLayer.height = strip.topLayer.height = strip.topImage.height;

        strip.topCtx.drawImage(strip.undoHistory.at(-1) || strip.topImage, 0, 0);
        strip.bottomCtx.drawImage(strip.bottomImage, 0, 0, width, height);
    }

    function addEvents() {
        strip.cursorLayer.addEventListener('pointerenter', (evt) => {
            strip.prevX = strip.currentX = evt.offsetX;
            strip.prevY = strip.currentY = evt.offsetY;

            if (evt.pressure) {
                strip.isDrawing = true;
            }

            if (!evt.pressure && strip.isDrawing) {
                strip.isDrawing = false;
                addStrokeToHistory();
            }
        });

        strip.cursorLayer.addEventListener('pointermove', (evt) => {
            strip.prevX = strip.currentX;
            strip.prevY = strip.currentY;
            strip.currentX = evt.offsetX;
            strip.currentY = evt.offsetY;
            drawCursor(strip.currentX, strip.currentY);
            if (evt.pressure) {
                strip.isDrawing = true;
                drawLine(strip.prevX, strip.prevY, strip.currentX, strip.currentY)
            };
        });

        strip.cursorLayer.addEventListener('pointerleave', (evt) => {
            strip.currentX = null;
            strip.currentY = null;
            clearCursor();
        });

        strip.cursorLayer.addEventListener('pointerdown', (evt) => {
            drawCursor(strip.currentX, strip.currentY);
            strip.isDrawing = true;
            drawArc(evt.offsetX, evt.offsetY);
        });

        strip.cursorLayer.addEventListener('pointerup', (evt) => {
            strip.isDrawing = false;
            addStrokeToHistory();
        });

        strip.cursorLayer.addEventListener('touchmove', (evt) => {
            if (evt.changedTouches.length === 1) evt.preventDefault();
        });
    }

    function addHotkeys() {
        document.addEventListener('keydown', (evt) => {
            if (document.activeElement.value !== undefined) return;
            switch (evt.key) {
                case '+':
                    setLineWidth(strip.lineWidth + 1);
                    break;
                case '-':
                    setLineWidth(Math.max(strip.lineWidth - 1, 1));
                    break;
                case 'Escape':
                    evt.preventDefault();
                    toggleFullView();
                    break;
                case 'z':
                    if (evt.ctrlKey && undo()) {
                        evt.preventDefault();
                    }
                    break;
                case 'y':
                    if (evt.ctrlKey && redo()) {
                        evt.preventDefault();
                    }
                    break;
            }
        });
    }

    function drawArc(x, y) {
        const scale = getScale();
        strip.topCtx.globalCompositeOperation = 'destination-out';
        strip.topCtx.beginPath();
        strip.topCtx.arc(x / scale, y / scale, strip.lineWidth / 2, 0, Math.PI * 2);
        strip.topCtx.fill();
    }

    function drawLine(x1, y1, x2, y2) {
        const scale = getScale();
        strip.topCtx.globalCompositeOperation = 'destination-out';
        strip.topCtx.beginPath();
        strip.topCtx.lineWidth = strip.lineWidth;
        strip.topCtx.lineJoin = 'round';
        strip.topCtx.moveTo(x1 / scale, y1 / scale);
        strip.topCtx.lineTo(x2 / scale, y2 / scale);
        strip.topCtx.closePath();
        strip.topCtx.stroke();
    }

    function drawCursor(x, y) {
        const scale = getScale();
        strip.cursorCtx.clearRect(0, 0, strip.cursorLayer.width, strip.cursorLayer.height);
        strip.cursorCtx.beginPath();
        strip.cursorCtx.arc(x / scale, y / scale, strip.lineWidth / 2, 0, Math.PI * 2);
        strip.cursorCtx.lineWidth = 1;
        strip.cursorCtx.strokeStyle = 'black';
        strip.cursorCtx.fillStyle = 'transparent';
        strip.cursorCtx.stroke();
    }

    function clearCursor() {
        strip.cursorCtx.clearRect(0, 0, strip.cursorLayer.width, strip.cursorLayer.height);
    }

    function getScale() {
        return strip.cursorLayer.getBoundingClientRect().width / strip.cursorLayer.width;
    }

    function setLineWidth(width) {
        strip.lineWidth = width;
        strip.lineWidthInput.value = strip.lineWidth;
        if (strip.currentX !== null) drawCursor(strip.currentX, strip.currentY);
    }

    function addStrokeToHistory() {
        const historyEntry = document.createElement('canvas');
        historyEntry.width = strip.topLayer.width;
        historyEntry.height  = strip.topLayer.height;

        const context = historyEntry.getContext('2d');
        context.drawImage(strip.bottomLayer, 0, 0);
        context.drawImage(strip.topLayer, 0, 0);

        strip.redoHistory = [];
        strip.undoHistory.push(historyEntry);
    }

    function undo() {
        if (strip.isDrawing) {
            strip.isDrawing = false;
            addStrokeToHistory();
        }

        if (!strip.undoHistory.length) return false;
        strip.redoHistory.push(strip.undoHistory.pop());

        strip.topCtx.globalCompositeOperation = 'source-over';
        strip.topCtx.drawImage(strip.undoHistory.at(-1) || strip.topImage, 0, 0);
        return true;
    }

    function redo() {
        if (strip.isDrawing) {
            strip.isDrawing = false;
            addStrokeToHistory();
        }

        if (!strip.redoHistory.length) return false;
        strip.undoHistory.push(strip.redoHistory.pop());

        strip.topCtx.globalCompositeOperation = 'source-over';
        strip.topCtx.drawImage(strip.undoHistory.at(-1), 0, 0);
        return true;
    }

    function download() {
        const downloadCanvas = document.createElement('canvas');
        downloadCanvas.width = strip.topLayer.width;
        downloadCanvas.height = strip.topLayer.height;

        const context = downloadCanvas.getContext('2d');
        context.drawImage(strip.bottomLayer, 0, 0);
        context.drawImage(strip.topLayer, 0, 0);

        const link = document.createElement('a');
        link.href = downloadCanvas.toDataURL('image/png');
        link.download = 'strip.png';
        link.click();
    }

    function toggleFullView() {
        if (strip.fullViewContainer.style.display !== 'block') {
            strip.fullViewContainer.style.display = 'block';
            while (strip.canvasContainer.firstChild) {
                strip.fullViewContainer.appendChild(strip.canvasContainer.firstChild);
            }
        } else {
            strip.fullViewContainer.style.display = 'none';
            while (strip.fullViewContainer.firstChild) {
                strip.canvasContainer.appendChild(strip.fullViewContainer.firstChild);
            }
        }
    }
})();