// ==UserScript==
// @name        Hacker News - Folding Subtrees
// @namespace   https://github.com/pdkl95/user_scripts
// @description Fold and unfold arbitrary comment subtrees.
// @include     https://news.ycombinator.com/item*
// @version     1.2
// @grant       none
// ==/UserScript==
/*
hacker_news-folding_subtrees.user.js
A user script to fold Hacker News.comments.
Copyright (C) 2015 Brent Sanders
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/
(function () {
var  icon_padding_px = 6;
var    post_selector = '.athing';
var  indent_selector = '.ind';
var  header_selector = '.default div:nth-child(1)';
var votebox_selector = 'tr td:nth-child(2)';
var style_r90        = ".rotate90  { transform: rotate(90deg);  }";
var style_r270       = ".rotate270 { transform: rotate(270deg); }";
var style_foldunfold = ".foldunfoldbtn { position: relative; top: -1px; }";
var style_fold       = '.foldbtn { opacity: 0.5; }';
var style_unfold     = '.unfoldbtn { opacity: 0.7; }';
var style_ctlbox     = '.foldctlbox { position: absolute; padding-left: ' + icon_padding_px + 'px; }';
var style_list = [style_r90, style_r270, style_foldunfold, style_fold, style_unfold, style_ctlbox];
var extra_style_sheet = document.createElement('style');
extra_style_sheet.type = 'text/css';
extra_style_sheet.appendChild(document.createTextNode(style_list.join("\n")));
var head = document.querySelector('head');
head.appendChild(extra_style_sheet);
var foldified_count = 0;
function hide (el) {
el.style.display = 'none';
}
function show_element (el, mode) {
if (el) {
el.style.display = mode;
}
}
function show_block        (el) { show_element(el, 'block'       ); }
function show_inline       (el) { show_element(el, 'inline'      ); }
function show_inline_block (el) { show_element(el, 'inline-block'); }
function set_toggle_button_fold (btn) {
btn.classList.add('foldbtn');
btn.classList.add('rotate90');
btn.classList.remove('unfoldbtn');
btn.classList.remove('rotate270');
}
function set_toggle_button_unfold (btn) {
btn.classList.remove('foldbtn');
btn.classList.remove('rotate90');
btn.classList.add('unfoldbtn');
btn.classList.add('rotate270');
}
function make_toggle_button (btn_type, rotation_class) {
var btn = document.createElement('div');
btn.classList.add('votearrow');
btn.classList.add('foldunfoldbtn');
set_toggle_button_fold(btn);
show_inline_block(btn);
return btn;
}
function each_subtree_post (post, func) {
if (!post.hasOwnProperty('indent_width')) { return; }
var width = post.indent_width || 0;
post = post.nextElementSibling;
while (post && post.hasOwnProperty('indent_width') && (post.indent_width > width)) {
func(post);
post = post.nextElementSibling;
}
}
function foldify_post(post_el, idx) {
var ind_el = post_el.querySelector(indent_selector);
if (!ind_el) { return; }
var spacer_img = ind_el.firstChild;
if (!spacer_img) { return; }
post_el.indent_width = spacer_img.width;
var  header_el = post_el.querySelector(header_selector);
var votebox_el = post_el.querySelector(votebox_selector);
var votepad_el = null;
var body_br_el = null;
var body_comment_el = null;
var body_pad_el = null;
if (header_el) {
post_el.header_el = header_el;
votepad_el = document.createElement('span');
votepad_el.style.display = 'none';
body_pad_el = document.createElement('div');
body_pad_el.classList.add('comment');
var comhead_el = header_el.querySelector('.comhead');
if (votebox_el) {
var icon_width = votebox_el.offsetWidth;
votepad_el.style.width = icon_width;
if (comhead_el) {
var comhead_width = comhead_el.offsetWidth;
body_pad_el.style.width = '' + (comhead_width + icon_width + icon_padding_px) + 'px';
}
}
header_el.insertBefore(votepad_el, header_el.firstChild);
body_br_el      = header_el.parentElement.children[1];
body_comment_el = header_el.parentElement.children[2];
header_el.parentElement.appendChild(body_pad_el);
}
var toggle_btn = make_toggle_button();
post_el.fold_self = function () {
post_el.is_folded = true;
set_toggle_button_unfold(toggle_btn);
hide(votebox_el);
show_inline_block(votepad_el);
hide(body_br_el);
hide(body_comment_el);
show_block(body_pad_el);
};
post_el.unfold_self = function () {
post_el.is_folded = false;
set_toggle_button_fold(toggle_btn);
show_block(votebox_el);
hide(votepad_el);
show_inline(body_br_el);
show_block(body_comment_el);
hide(body_pad_el);
};
post_el.fold_subtree = function () {
each_subtree_post(post_el, function (post) { post.fold_self(); });
};
post_el.unfold_subtree = function () {
each_subtree_post(post_el, function (post) { post.unfold_self(); });
};
post_el.fold = function () {
post_el.fold_self();
post_el.fold_subtree();
};
post_el.unfold = function () {
post_el.unfold_self();
post_el.unfold_subtree();
};
post_el.is_folded = false;
post_el.toggle_fold = function () {
if (post_el.is_folded) {
post_el.unfold();
} else {
post_el.fold();
}
};
var toggle_event = function (event) {
post_el.toggle_fold();
};
toggle_btn.addEventListener('click', toggle_event, false);
var ctl_box = document.createElement('div');
ctl_box.classList.add('foldctlbox');
ctl_box.appendChild(toggle_btn);
show_inline_block(ctl_box);
header_el.appendChild(ctl_box);
foldified_count = foldified_count + 1;
}
function setup_posts () {
var posts = document.querySelectorAll(post_selector);
/*console.log('found ' + posts.length + ' posts');*/
if (posts) {
Array.prototype.forEach.call(posts, foldify_post);
}
}
setup_posts();
/*console.log("foldified " + foldified_count + ' posts');*/
})();