// ==UserScript==
// @name         Enlarge images on iichan
// @namespace    http://iichan.hk/
// @license      WTFPL
// @version      0.1
// @description  adds image enlargement on click to iichan
// @author       Cirno
// @match        http://iichan.hk/*
// @grant        none
// ==/UserScript==

(function() {
    'use strict';
    var MIN_DISPLAY_SIZE = 700;  // ширина или высота, при которой картинки будут открываться как обычно

    var thumbs = document.querySelectorAll('.thumb');

    function removeClass(el, className) {
        var reg = new RegExp('(\\s|^)' + className + '(\\s|$)');
        el.className = el.className.replace(reg, ' ');
    }

    function hasClass(el, className) {
        if(!className) return false;
        return (' ' + el.className + ' ').indexOf(' ' + className + ' ') !== -1;
    }

    for (var i = thumbs.length - 1; i >= 0; i--) {
        var img = thumbs[i];
        var a = img.parentNode;
        a.addEventListener('click', function(e) {
            if (screen.width < MIN_DISPLAY_SIZE || screen.height < MIN_DISPLAY_SIZE) {
                return;
            }
            e.preventDefault();
            console.log(this);
            var thumb = this.querySelector('.thumb');

            if (hasClass(thumb, 'iichan-image-fullsize')) {
                thumb.src = thumb.originalSrc;
                thumb.width = thumb.originalWidth;
                thumb.height = thumb.originalHeight;
                removeClass(thumb, 'iichan-image-fullsize');
                return;
            }
            var imageSrc = this.href;
            var thumbSrc = thumb.src;
            thumb.originalSrc = thumb.src;
            thumb.originalWidth = thumb.width;
            thumb.originalHeight = thumb.height;
            thumb.removeAttribute('width');
            thumb.removeAttribute('height');
            thumb.className += ' iichan-image-fullsize';
            thumb.src = imageSrc;
        });
    }

    function appendCSS() {
        var css = document.createElement('style');
        css.type = 'text/css';
        css.innerHTML =  '\
.iichan-image-fullsize {\
max-width: 97%;\
max-height: 97%;\
}\
';
        document.body.appendChild(css);
    }

    appendCSS();
})();