zulip/zephyr/static/js/message_list.js

611 lines
22 KiB
JavaScript

/*jslint nomen: true */
function MessageList(table_name, filter, opts) {
$.extend(this, {collapse_messages: true}, opts);
this._items = [];
this._hash = {};
this.table_name = table_name;
this.filter = filter;
this._selected_id = -1;
this._message_groups = [];
// Half-open interval of the indices that define the current render window
this._render_win_start = 0;
this._render_win_end = 0;
if (this.table_name) {
this._clear_table();
}
if (this.filter === undefined) {
this.filter = new narrow.Filter();
}
this.narrowed = false;
if (this.table_name === "zfilt") {
this.narrowed = true;
}
return this;
}
(function () {
function add_display_time(message, prev) {
if (message.timestr !== undefined) {
return;
}
var two_digits = function (x) { return ('0' + x).slice(-2); };
var time = new XDate(message.timestamp * 1000);
var include_date = message.include_recipient;
if (prev !== undefined) {
var prev_time = new XDate(prev.timestamp * 1000);
if (time.toDateString() !== prev_time.toDateString()) {
include_date = true;
}
}
// NB: timestr is HTML, inserted into the document without escaping.
if (include_date) {
message.timestr = (timerender.render_time(time))[0].outerHTML;
} else {
message.timestr = time.toString("HH:mm");
}
}
MessageList.prototype = {
get: function MessageList_get(id) {
id = parseInt(id, 10);
if (isNaN(id)) {
return undefined;
}
return this._hash[id];
},
empty: function MessageList_empty() {
return this._items.length === 0;
},
first: function MessageList_first() {
return this._items[0];
},
last: function MessageList_last() {
return this._items[this._items.length - 1];
},
_clear_table: function MessageList__clear_table() {
// We do not want to call .empty() because that also clears
// jQuery data. This does mean, however, that we need to be
// mindful of memory leaks.
rows.get_table(this.table_name).children().detach();
},
_clear_rendering_state: function MessageList__clear_rendering_state() {
this._message_groups = [];
this._clear_table();
this.last_message_historical = false;
},
clear: function MessageList_clear(opts) {
opts = $.extend({}, {clear_selected_id: true}, opts);
this._items = [];
this._hash = {};
this._clear_rendering_state();
if (opts.clear_selected_id) {
this._selected_id = -1;
}
},
selected_id: function MessageList_selected_id() {
return this._selected_id;
},
select_id: function MessageList_select_id(id, opts) {
opts = $.extend({then_scroll: false, use_closest: false}, opts, {id: id,
msg_list: this,
previously_selected: this._selected_id});
id = parseInt(id, 10);
if (isNaN(id)) {
blueslip.fatal("Bad message id");
}
if (this.get(id) === undefined) {
if (!opts.use_closest) {
blueslip.error("Selected message id not in MessageList",
{table_name: this.table_name, id: id});
}
id = this.closest_id(id);
opts.id = id;
}
this._selected_id = id;
this._maybe_rerender();
$(document).trigger($.Event('message_selected.zephyr', opts));
},
selected_message: function MessageList_selected_message() {
return this.get(this._selected_id);
},
selected_row: function MessageList_selected_row() {
return rows.get(this._selected_id, this.table_name);
},
closest_id: function MessageList_closest_id(id) {
if (this._items.length === 0) {
return -1;
}
var closest = util.lower_bound(this._items, id,
function (a, b) {
return a.id < b;
});
if (closest === this._items.length
|| (closest !== 0
&& (id - this._items[closest - 1].id <
this._items[closest].id - id)))
{
closest = closest - 1;
}
return this._items[closest].id;
},
_add_to_hash: function MessageList__add_to_hash(messages) {
var self = this;
messages.forEach(function (elem) {
var id = parseInt(elem.id, 10);
if (isNaN(id)) {
blueslip.fatal("Bad message id");
}
if (self._hash[id] !== undefined) {
blueslip.error("Duplicate message added to MessageList");
return;
}
self._hash[id] = elem;
});
},
// Number of messages to render at a time
_RENDER_WINDOW_SIZE: 400,
// Number of messages away from edge of render window at which we
// trigger a re-render
_RENDER_THRESHOLD: 50,
_update_render_window: function MessageList__update_render_window(selected_idx, check_for_changed) {
var new_start = Math.max(selected_idx - this._RENDER_WINDOW_SIZE / 2, 0);
if (check_for_changed && new_start === this._render_win_start) {
return false;
}
this._render_win_start = new_start;
this._render_win_end = Math.min(this._render_win_start + this._RENDER_WINDOW_SIZE,
this._items.length);
return true;
},
_selected_idx: function MessageList__selected_idx() {
return util.lower_bound(this._items, this._selected_id,
function (a, b) { return a.id < b; });
},
_maybe_rerender: function MessageList__maybe_rerender() {
if (this.table_name === undefined) {
return false;
}
var selected_idx = this._selected_idx();
// We rerender under the following conditions:
// * The selected message is within this._RENDER_THRESHOLD messages
// of the top of the currently rendered window and the top
// of the window does not abut the beginning of the message
// list
// * The selected message is within this._RENDER_THRESHOLD messages
// of the bottom of the currently rendered window and the
// bottom of the window does not abut the end of the
// message list
if (! (((selected_idx - this._render_win_start < this._RENDER_THRESHOLD)
&& (this._render_win_start !== 0)) ||
((this._render_win_end - selected_idx <= this._RENDER_THRESHOLD)
&& (this._render_win_end !== this._items.length))))
{
return false;
}
if (!this._update_render_window(selected_idx, true)) {
return false;
}
this._rerender_preserving_scrolltop();
return true;
},
_rerender_preserving_scrolltop: function MessageList__rerender_preserving_scrolltop() {
// scrolltop_offset is the number of pixels between the top of the
// viewable window and the newly selected message
var scrolltop_offset;
var selected_row = rows.get(this._selected_id, this.table_name);
var selected_in_view = (selected_row.length > 0);
if (selected_in_view) {
scrolltop_offset = viewport.scrollTop() - selected_row.offset().top;
}
this._clear_table();
this._render(this._items.slice(this._render_win_start,
this._render_win_end), 'bottom');
// If we could see the newly selected message, scroll the
// window such that the newly selected message is at the
// same location as it would have been before we
// re-rendered.
if (selected_in_view) {
viewport.scrollTop(rows.get(this._selected_id, this.table_name).offset().top + scrolltop_offset);
}
},
_render: function MessageList__render(messages, where) {
if (messages.length === 0 || this.table_name === undefined)
return;
var self = this;
var table_name = this.table_name;
var table = rows.get_table(table_name);
var messages_to_render = [];
var ids_where_next_is_same_sender = {};
var prev;
var last_message_id;
var current_group = [];
var new_message_groups = [];
if (where === "bottom") {
// Remove the trailing bookend; it'll be re-added after we do our rendering
this.clear_trailing_bookend();
}
if (where === 'top' && this.collapse_messages && this._message_groups.length > 0) {
// Delete the current top message group, and add it back in with these
// messages, in order to collapse properly.
//
// This means we redraw the entire view on each update when narrowed by
// subject, which could be a problem down the line. For now we hope
// that subject views will not be very big.
var top_group = this._message_groups[0];
var top_messages = [];
$.each(top_group, function (index, id) {
rows.get(id, table_name).remove();
top_messages.push(self.get(id));
});
messages = messages.concat(top_messages);
// Delete the leftover recipient label.
table.find('.recipient_row:first').remove();
} else {
last_message_id = rows.id(table.find('tr[zid]:last'));
prev = this.get(last_message_id);
}
$.each(messages, function (index, message) {
message.include_recipient = false;
message.include_bookend = false;
if (util.same_recipient(prev, message) && self.collapse_messages &&
prev.historical === message.historical) {
current_group.push(message.id);
} else {
if (current_group.length > 0)
new_message_groups.push(current_group);
current_group = [message.id];
// Add a space to the table, but not for the first element.
message.include_recipient = true;
message.include_bookend = (prev !== undefined);
message.subscribed = false;
message.unsubscribed = false;
if (message.include_bookend && message.historical !== prev.historical) {
if (message.historical) {
message.unsubscribed = message.stream;
} else {
message.subscribed = message.stream;
}
}
}
message.include_sender = true;
if (!message.include_recipient &&
util.same_sender(prev, message) &&
(Math.abs(message.timestamp - prev.timestamp) < 60*10)) {
message.include_sender = false;
ids_where_next_is_same_sender[prev.id] = true;
}
add_display_time(message, prev);
if (message.last_edit_timestamp !== undefined &&
message.last_edit_timestr === undefined) {
// Add or update the last_edit_timestr
var last_edit_time = new XDate(message.last_edit_timestamp * 1000);
message.last_edit_timestr = (timerender.render_time(last_edit_time))[0].outerHTML;
}
message.dom_id = table_name + message.id;
if (message.sender_email === page_params.email) {
message.stamp = ui.get_gravatar_stamp();
}
if (message.is_stream) {
message.background_color = subs.get_color(message.stream);
message.color_class = subs.get_color_class(message.background_color);
message.invite_only = subs.get_invite_only(message.stream);
}
message.contains_mention = notifications.speaking_at_me(message);
messages_to_render.push(message);
prev = message;
self.last_message_historical = message.historical;
});
if (messages_to_render.length === 0) {
return;
}
if (current_group.length > 0)
new_message_groups.push(current_group);
if (where === 'top') {
this._message_groups = new_message_groups.concat(this._message_groups);
} else {
this._message_groups = this._message_groups.concat(new_message_groups);
}
var rendered_elems = $(templates.render('message', {
messages: messages_to_render,
include_layout_row: (table.find('tr:first').length === 0),
use_match_properties: this.filter.is_search()
}));
$.each(rendered_elems, function (index, elem) {
var row = $(elem);
if (! row.hasClass('message_row')) {
return;
}
var id = rows.id(row);
if (ids_where_next_is_same_sender[id]) {
row.find('.messagebox').addClass("next_is_same_sender");
}
});
// The message that was last before this batch came in has to be
// handled specially because we didn't just render it and
// therefore have to lookup its associated element
if (last_message_id !== undefined
&& ids_where_next_is_same_sender[last_message_id])
{
var row = rows.get(last_message_id, table_name);
row.find('.messagebox').addClass("next_is_same_sender");
}
if (where === 'top' && table.find('.ztable_layout_row').length > 0) {
// If we have a totally empty narrow, there may not
// be a .ztable_layout_row.
table.find('.ztable_layout_row').after(rendered_elems);
} else {
table.append(rendered_elems);
this.update_trailing_bookend();
// XXX: This is absolutely awful. There is a firefox bug
// where when table rows as DOM elements are appended (as
// opposed to as a string) a border is sometimes added to the
// row. This border goes away if we add a dummy row to the
// top of the table (it doesn't go away on any reflow,
// though, as resizing the window doesn't make them go away).
// So, we add an empty row and then garbage collect them
// later when the user is idle.
var dummy = $("<tr></tr>");
table.find('.ztable_layout_row').after(dummy);
$(document).idle({'idle': 1000*10,
'onIdle': function () {
dummy.remove();
}});
}
$.each(rendered_elems, function(idx, elem) {
var row = $(elem);
if (! row.hasClass('message_row')) {
return;
}
var id = rows.id(row);
message_edit.maybe_show_edit(row, id);
});
$.each(rendered_elems, ui.process_condensing);
// Re-add the fading of messages that is lost when we re-render.
compose.update_faded_messages();
if (this === current_msg_list) {
this._maybe_autoscroll(rendered_elems);
}
},
_maybe_autoscroll: function MessageList__maybe_autoscroll(rendered_elems) {
// If we are near the bottom of our feed (the bottom is visible) and can
// scroll up without moving the pointer out of the viewport, do so, by
// up to the amount taken up by the new message.
var selected_row = current_msg_list.selected_row();
var last_visible = rows.last_visible();
// Make sure we have a selected row and last visible row. (defensive)
if (!(selected_row && (selected_row.length > 0) && last_visible)) {
return;
}
var selected_row_offset = selected_row.offset().top;
var info = viewport.message_viewport_info();
var available_space_for_scroll = selected_row_offset - info.visible_top;
// Don't scroll if we can't move the pointer up.
if (available_space_for_scroll <= 0) {
return;
}
var new_messages_height = 0;
$.each(rendered_elems, function() {
// Sometimes there are non-DOM elements in rendered_elems; only
// try to get the heights of actual trs.
if ($(this).is("tr")) {
new_messages_height += $(this).height();
}
});
if (new_messages_height <= 0) {
return;
}
// This next decision is fairly debatable. For a big message that
// would push the pointer off the screen, we do a partial autoscroll,
// which has the following implications:
// a) user sees scrolling (good)
// b) user's pointer stays on screen (good)
// c) scroll amount isn't really tied to size of new messages (bad)
// d) all the bad things about scrolling for users who want messages
// to stay on the screen
var scroll_amount = new_messages_height;
if (scroll_amount > available_space_for_scroll) {
scroll_amount = available_space_for_scroll;
}
// Let's work our way back to whether the user was already dealing
// with messages off the screen, in which case we shouldn't autoscroll.
var bottom_last_visible = last_visible.offset().top + last_visible.height();
var bottom_old_last_visible = bottom_last_visible - new_messages_height;
var bottom_viewport = info.visible_top + info.visible_height;
// Exit if the user was already past the bottom.
if (bottom_old_last_visible > bottom_viewport) {
return;
}
// Ok, we are finally ready to actually scroll.
viewport.system_initiated_animate_scroll(scroll_amount);
},
clear_trailing_bookend: function MessageList_clear_trailing_bookend() {
var trailing_bookend = rows.get_table(this.table_name).find('#trailing_bookend');
trailing_bookend.remove();
},
// Maintains a trailing bookend element explaining any changes in
// your subscribed/unsubscribed status at the bottom of the
// message list.
update_trailing_bookend: function MessageList_update_trailing_bookend() {
this.clear_trailing_bookend();
if (!this.narrowed) {
return;
}
var stream = narrow.stream();
if (stream === undefined) {
return;
}
var trailing_bookend_content, subscribed = subs.is_subscribed(stream);
if (subscribed) {
if (this.last_message_historical) {
trailing_bookend_content = "--- Subscribed to stream " + stream + " ---";
}
} else {
if (!this.last_message_historical) {
trailing_bookend_content = "--- Unsubscribed from stream " + stream + " ---";
} else {
trailing_bookend_content = "--- Not subscribed to stream " + stream + " ---";
}
}
if (trailing_bookend_content !== undefined) {
var rendered_trailing_bookend = $(templates.render('trailing_bookend', {
trailing_bookend: trailing_bookend_content
}));
rows.get_table(this.table_name).append(rendered_trailing_bookend);
}
},
append: function MessageList_append(messages) {
this._items = this._items.concat(messages);
this._add_to_hash(messages);
var cur_window_size = this._render_win_end - this._render_win_start;
if (cur_window_size < this._RENDER_WINDOW_SIZE) {
var slice_to_render = messages.slice(0, this._RENDER_WINDOW_SIZE - cur_window_size);
this._render(slice_to_render, 'bottom');
this._render_win_end += slice_to_render.length;
}
// If the pointer is high on the page such that there is a
// lot of empty space below and the render window is full, a
// newly recieved message should trigger a rerender so that
// the new message, which will appear in the viewable area,
// is rendered.
this._maybe_rerender();
},
prepend: function MessageList_prepend(messages) {
this._items = messages.concat(this._items);
this._add_to_hash(messages);
this._render_win_start += messages.length;
this._render_win_end += messages.length;
},
add_and_rerender: function MessageList_add_and_rerender(messages) {
// To add messages that might be in the interior of our
// existing messages list, we just add the new messages and
// then rerender the whole thing.
this._items = messages.concat(this._items);
this._items.sort(function(a, b) {return a.id - b.id;});
this._add_to_hash(messages);
this._clear_rendering_state();
this._update_render_window(this._selected_idx(), false);
this._render(this._items.slice(this._render_win_start,
this._render_win_end), 'bottom');
},
show_edit_message: function MessageList_show_edit_message(row, edit_obj) {
row.find(".message_edit_form").empty().append(edit_obj.form);
row.find(".message_content").hide();
row.find(".message_edit").show();
},
hide_edit_message: function MessageList_hide_edit_message(row) {
row.find(".message_content").show();
row.find(".message_edit").hide();
},
rerender: function MessageList_rerender() {
// We need to clear the rendering state, rather than just
// doing _clear_table, since we want to potentially recollapse
// things.
this._clear_rendering_state();
this._rerender_preserving_scrolltop();
if (this._selected_id !== -1) {
this.select_id(this._selected_id);
}
},
all: function MessageList_all() {
return this._items;
}
};
// We stop autoscrolling when the user is clearly in the middle of
// doing something. Be careful, though, if you try to capture
// mousemove, then you will have to contend with the autoscroll
// itself generating mousemove events.
$(document).on('message_selected.zephyr hashchange.zephyr mousewheel', function (event) {
viewport.stop_auto_scrolling();
});
}());
/*jslint nomen: false */