Removing extra divs

There is a div with id "chat-messages"

Gradually, divs with id "message-ID MESSAGES" are added to it

Example:

<div id="chat-messages"> <div id="message-1">Сообщение 1</div> <div id="message-2">Сообщение 2</div> <div id="message-3">Сообщение 3</div> </div> 

It is necessary to delete all the old divas so that the chat-messages block has a maximum of 60 messages.

Js:

 UMBRELLA.modules.jchat.js = { messages_id: null, div_reload: true, tmp: { ci: '<div class="mainChat mainNew" id="mainChat"></div>', cm: [ '<div id="subChat-closebar" onclick="UMBRELLA.modules.jchat.js.close()">Скрыть чат (Фонд: <span id="jchat-fond"></span>)</div><div id="subChat-messages"><span id="jchat-message"></span></div><input type="text" id="JChat-message" onkeyup="UMBRELLA.modules.jchat.js.keyboard(event.keyCode)" maxlength="300" style="width: 406px; left: -5px; position: relative;"><span class="f-buttons" style="left: -2px; position: relative;"> <span class="f-bu f-bu-success" onclick="UMBRELLA.modules.chat.postmsg()"><input type="button" class="chatSprite" id="chs-30"> Сказать</span> <span class="f-bu"><input id="chs-31" class="chatSprite" type="button"> Бар</span></span>', '<div id="subChat-closebar" onclick="UMBRELLA.modules.jchat.js.open()">Показать чат</div>' ] }, fa: { fp: function() { $('body').append(UMBRELLA.modules.jchat.js.tmp.ci); $('#mainChat').append(UMBRELLA.modules.jchat.js.tmp.cm[0]); return true; } }, keyboard: function(kid) { if (kid == 13) UMBRELLA.modules.jchat.js.action.post(); }, close: function() { UMBRELLA.modules.jchat.js.div_reload = false; $(".mainChat").html(UMBRELLA.modules.jchat.js.tmp.cm[1]); }, open: function() { UMBRELLA.modules.jchat.js.div_reload = true; UMBRELLA.modules.jchat.js.messages_id = 0; $(".mainChat").html(UMBRELLA.modules.jchat.js.tmp.cm[0]); UMBRELLA.modules.javax.call($.toJSON({ request: "chat", type: "getChats", id: UMBRELLA.modules.jchat.js.messages_id })); }, calls: { make: function(a) { if (UMBRELLA.modules.jchat.js.fa.fp()) { a(); $.cookie('tmp_jchat_rt', 0); } }, jchat: function(a) { var c = JSON.parse(a); if (c.request == 'chat') { if (c.type == 'jchaterror') { if (c.errid == '001') { UMBRELLA.plugins.mainWindow.message('Ошибка!', 'Заполните поле сообщения перед отправкой.'); } else if (c.errid == '002') { UMBRELLA.plugins.mainWindow.message('Ошибка!', 'Вы отключены от чата на ' + c.time + ' минут. Причина: ' + c.reason + '.'); } } if (c.type == 'chats') { $("#jchat-fond").text(c.fond); if (!c.messages) { return false; } for (var i = 0; i < c.messages.length; i++) { UMBRELLA.modules.jchat.js.messages_id = c.messages[i].id; $("#jchat-message").prepend('<div class="subChat-message" id="jchat-' + c.messages[i].id + '" ' + (c.messages[i].touser[0] == MY.id ? 'style="background: rgba(255,255,255, 0.1);border: solid 1px #093406;"' : '') + '><span>' /* */ + (c.messages[i].system == 3 ? '<font color="#32CD32"><b>' + c.messages[i].message + '</b></font>' : (c.messages[i].system == 2 ? '<span><b><div class="f-bwi"><img class="f-bwi-pic" width="84" height="85" alt="Gold" src="/img/1353213729.png"></img><div class="f-bwi-text"><input id="spriteRank' + c.messages[i].user[0] + '" class="sprite" type="button"></input> <b>' + c.messages[i].message + '</b><br>Поймал бонусный ящик с 100 еденицами опыта.</div></div></b></span>' : (c.messages[i].system == 0 ? /* */ (c.messages[i].pm != 0 ? '[PM]' : '') + '<input style="box-shadow: none; background-color: transparent;" type="button" class="sprite" id="spriteRank' + c.messages[i].user[0] + '" /><b>' + c.messages[i].user[1] + '</b></span>' + (c.messages[i].touser.length != 0 ? ' → <span><input style="box-shadow: none; background-color: transparent;" type="button" class="sprite" id="spriteRank' + c.messages[i].touser[0] + '" /><b>' + c.messages[i].touser[1] + '</b>:</span> ' : ': ') + c.messages[i].message /**/ : 'Наблюдатель'))) /**/ + '</div>'); } } } }, open: function(a) { if (a[0] == 'chat') { var b = (function() { UMBRELLA.modules.javax.call($.toJSON({ request: "chat", type: "getChats", id: "0" })) }); } UMBRELLA.modules.jchat.js.calls.make(b); }, refresh: function(a) { if (UMBRELLA.modules.jchat.js.div_reload != false) { if (a != 'post') { if ($.cookie('tmp_jchat_rt') < Math.floor((new Date()).getTime() / 1000)) { UMBRELLA.modules.javax.call($.toJSON({ request: "chat", type: "getChats", id: UMBRELLA.modules.jchat.js.messages_id })); } } else { UMBRELLA.modules.javax.call($.toJSON({ request: "chat", type: "getChats", id: UMBRELLA.modules.jchat.js.messages_id })); } } } }, action: { post: function() { var message = $("#JChat-message").val(); $("#JChat-message").attr("value", ""); var b = UMBRELLA.modules.javax.call($.toJSON({ request: "chat", type: "setMessages", text: message })); UMBRELLA.modules.jchat.js.calls.refresh('post'); $.cookie('tmp_jchat_rt', Math.floor((new Date()).getTime() / 1000) + 1500); } } }; $(document).ready(function() { setInterval(function() { UMBRELLA.modules.jchat.js.calls.refresh() }, 5000); });