zulip/static/js/buddy_list.js

345 lines
8.9 KiB
JavaScript

const render_user_presence_row = require('../templates/user_presence_row.hbs');
const render_user_presence_rows = require('../templates/user_presence_rows.hbs');
function buddy_list_conf() {
const conf = {};
conf.container_sel = '#user_presences';
conf.scroll_container_sel = '#buddy_list_wrapper';
conf.item_sel = 'li.user_sidebar_entry';
conf.padding_sel = '#buddy_list_wrapper_padding';
conf.items_to_html = function (opts) {
const user_info = opts.items;
const html = render_user_presence_rows({users: user_info});
return html;
};
conf.item_to_html = function (opts) {
const html = render_user_presence_row(opts.item);
return html;
};
conf.get_li_from_key = function (opts) {
const user_id = opts.key;
const container = $(conf.container_sel);
const sel = conf.item_sel + "[data-user-id='" + user_id + "']";
return container.find(sel);
};
conf.get_key_from_li = function (opts) {
const user_id = opts.li.expectOne().attr('data-user-id');
return user_id;
};
conf.get_data_from_keys = function (opts) {
const keys = opts.keys;
const data = buddy_data.get_items_for_users(keys);
return data;
};
conf.compare_function = buddy_data.compare_function;
conf.height_to_fill = function () {
// Because the buddy list gets sized dynamically, we err on the side
// of using the height of the entire viewport for deciding
// how much content to render. Even on tall monitors this should
// still be a significant optimization for orgs with thousands of
// users.
const height = message_viewport.height();
return height;
};
return conf;
}
function buddy_list_create() {
const conf = buddy_list_conf();
const self = {};
self.container_sel = conf.container_sel;
self.scroll_container_sel = conf.scroll_container_sel;
self.item_sel = conf.item_sel;
self.padding_sel = conf.padding_sel;
const func_names = [
'items_to_html',
'item_to_html',
'get_li_from_key',
'get_key_from_li',
'get_data_from_keys',
'compare_function',
'height_to_fill',
];
_.each(func_names, function (func_name) {
self[func_name] = conf[func_name];
});
self.keys = [];
self.populate = function (opts) {
self.render_count = 0;
self.container.html('');
// We rely on our caller to give us items
// in already-sorted order.
self.keys = _.map(opts.keys, function (k) {
return k.toString();
});
self.fill_screen_with_content();
};
self.render_more = function (opts) {
const chunk_size = opts.chunk_size;
const begin = self.render_count;
const end = begin + chunk_size;
const more_keys = self.keys.slice(begin, end);
if (more_keys.length === 0) {
return;
}
const items = self.get_data_from_keys({
keys: more_keys,
});
const html = self.items_to_html({
items: items,
});
self.container = $(self.container_sel);
self.container.append(html);
// Invariant: more_keys.length >= items.length.
// (Usually they're the same, but occasionally keys
// won't return valid items. Even though we don't
// actually render these keys, we still "count" them
// as rendered.
self.render_count += more_keys.length;
self.update_padding();
};
self.get_items = function () {
const obj = self.container.find(self.item_sel);
return obj.map(function (i, elem) {
return $(elem);
});
};
self.first_key = function () {
return self.keys[0];
};
self.prev_key = function (key) {
const i = self.keys.indexOf(key.toString());
if (i <= 0) {
return;
}
return self.keys[i - 1];
};
self.next_key = function (key) {
const i = self.keys.indexOf(key.toString());
if (i < 0) {
return;
}
return self.keys[i + 1];
};
self.maybe_remove_key = function (opts) {
const pos = self.keys.indexOf(opts.key);
if (pos < 0) {
return;
}
self.keys.splice(pos, 1);
if (pos < self.render_count) {
self.render_count -= 1;
const li = self.find_li({key: opts.key});
li.remove();
self.update_padding();
}
};
self.find_position = function (opts) {
const key = opts.key;
let i;
for (i = 0; i < self.keys.length; i += 1) {
const list_key = self.keys[i];
if (self.compare_function(key, list_key) < 0) {
return i;
}
}
return self.keys.length;
};
self.force_render = function (opts) {
const pos = opts.pos;
// Try to render a bit optimistically here.
const cushion_size = 3;
const chunk_size = pos + cushion_size - self.render_count;
if (chunk_size <= 0) {
blueslip.error('cannot show key at this position: ' + pos);
}
self.render_more({
chunk_size: chunk_size,
});
};
self.find_li = function (opts) {
const key = opts.key.toString();
// Try direct DOM lookup first for speed.
let li = self.get_li_from_key({
key: key,
});
if (li.length === 1) {
return li;
}
if (!opts.force_render) {
// Most callers don't force us to render a list
// item that wouldn't be on-screen anyway.
return li;
}
const pos = self.keys.indexOf(key);
if (pos < 0) {
// TODO: See list_cursor.get_row() for why this is
// a bit janky now.
return [];
}
self.force_render({
pos: pos,
});
li = self.get_li_from_key({
key: key,
});
return li;
};
self.insert_new_html = function (opts) {
const other_key = opts.other_key;
const html = opts.html;
const pos = opts.pos;
if (other_key === undefined) {
if (pos === self.render_count) {
self.render_count += 1;
self.container.append(html);
self.update_padding();
}
return;
}
if (pos < self.render_count) {
self.render_count += 1;
const li = self.find_li({key: other_key});
li.before(html);
self.update_padding();
}
};
self.insert_or_move = function (opts) {
const key = opts.key.toString();
const item = opts.item;
self.maybe_remove_key({key: key});
const pos = self.find_position({
key: key,
});
// Order is important here--get the other_key
// before mutating our list. An undefined value
// corresponds to appending.
const other_key = self.keys[pos];
self.keys.splice(pos, 0, key);
const html = self.item_to_html({item: item});
self.insert_new_html({
pos: pos,
html: html,
other_key: other_key,
});
};
self.fill_screen_with_content = function () {
let height = self.height_to_fill();
const elem = ui.get_scroll_element($(self.scroll_container_sel)).expectOne()[0];
// Add a fudge factor.
height += 10;
while (self.render_count < self.keys.length) {
const padding_height = $(self.padding_sel).height();
const bottom_offset = elem.scrollHeight - elem.scrollTop - padding_height;
if (bottom_offset > height) {
break;
}
const chunk_size = 20;
self.render_more({
chunk_size: chunk_size,
});
}
};
// This is a bit of a hack to make sure we at least have
// an empty list to start, before we get the initial payload.
self.container = $(self.container_sel);
self.start_scroll_handler = function () {
// We have our caller explicitly call this to make
// sure everything's in place.
const scroll_container = ui.get_scroll_element($(self.scroll_container_sel));
scroll_container.scroll(function () {
self.fill_screen_with_content();
});
};
self.update_padding = function () {
padded_widget.update_padding({
shown_rows: self.render_count,
total_rows: self.keys.length,
content_sel: self.container_sel,
padding_sel: self.padding_sel,
});
};
return self;
}
const buddy_list = buddy_list_create();
module.exports = buddy_list;
window.buddy_list = buddy_list;