// ==UserScript==
// @name         NGA 帖子过滤器
// @namespace    https://greasyfork.org/zh-CN/scripts/28659-nga-%E5%B8%96%E5%AD%90%E8%BF%87%E6%BB%A4%E5%99%A8
// @version      0.0.1.1
// @description  超简易NGA论坛帖子过滤器
// @author       F1re
// @include      /^https?://(bbs\.ngacn\.cc|nga\.178\.com|bbs\.nga\.cn)/.+/
// @grant        none
// @require      http://cdn.bootcss.com/jquery/3.2.1/jquery.min.js
// @downloadURL none
// ==/UserScript==

var $Q = jQuery.noConflict();

(function() {
    
    // textbox for regular expression
    var regex_textbox=document.createElement('input');
    regex_textbox.type='textarea';
    regex_textbox.rows='2';
    regex_textbox.cols='50';
    regex_textbox.value='.+萌新|监狱塔.+';
    
    // filter button
    var filter_btn=document.createElement('input');
    filter_btn.type='button';
    filter_btn.value='过滤';
    filter_btn.onclick = filter_handler;
    var box = $Q('table#topicrows.forumbox')[0];
    
    box.parentNode.insertBefore(regex_textbox,box);
    box.parentNode.insertBefore(filter_btn,box);
    
    function filter_handler(){
        if(this.value=="还原"){
            this.value="过滤";
            showall();
        } else {
            this.value="还原";
            filter();
        }
    }
    
    function showall(){
        var rows = $Q('.topicrow*');
        for(i = 0; i < rows.length; i++) {
            rows[i].style.display = '';
        }
    }
    
    function filter(){
        var regex = new RegExp(regex_textbox.value);
        var rows = $Q('.topicrow*');
        for(i = 0; i < rows.length; i++) {
            var row = rows[i];
            // filter posts matched by regex, excluding elevated posts
            if(row.children[1].children[1].className=='topic' && regex.test(row.childNodes[3].innerText)) {
                row.style.display = 'none';
            } else {
                row.style.display = '';
            }
        }
    }
})();