function RunChat(cfg) {
    cfg.divChat = GetElement(cfg.divChat);
    cfg.divChatContainer = GetElement(cfg.divChatContainer);
    cfg.lblTitle = GetElement(cfg.lblTitle);
    cfg.txtText = GetElement(cfg.txtText);
    cfg.btnSend = GetElement(cfg.btnSend);

    cfg.LastUser = null;

    cfg.lblTitle.innerHTML = cfg.Texts.Chat;
    cfg.lblTitle.className = "titleChatNormal";
    cfg.divChatContainer.style.width = 0;
    cfg.divChatContainer.style.height = 0;
    cfg.divChatContainer.style.opacity = 0;

    cfg.Minimized = true;
    cfg.Connected = null;
    cfg.FirstMessages = true;
    cfg.ScrollOnRestore = true;
    cfg.ScrollPosition = 0;

    cfg.lblTitle.onclick = function () {
        if (cfg.Minimized) {
            cfg.divChatContainer.style.width = cfg.divChatContainerWidth;
            cfg.divChatContainer.style.height = cfg.divChatContainerHeight;
            cfg.divChatContainer.style.opacity = 1;
            if (cfg.Connected) {
                cfg.lblTitle.innerHTML = cfg.Texts.Close;
                cfg.lblTitle.className = "titleChatNormal";
            }
            if (cfg.ScrollOnRestore) {
                cfg.divChat.scrollTop = cfg.divChat.scrollHeight;
            } else {
                cfg.divChat.scrollTop = cfg.ScrollPosition;
            }
            cfg.Minimized = false;
        } else {
            cfg.ScrollPosition = cfg.divChat.scrollTop;
            var scrollVisible = cfg.divChat.scrollHeight - cfg.divChat.offsetHeight;
            cfg.ScrollOnRestore = cfg.divChat.scrollTop > scrollVisible;
            cfg.divChatContainer.style.width = 0;
            cfg.divChatContainer.style.height = 0;
            cfg.divChatContainer.style.opacity = 0;
            if (cfg.Connected) {
                cfg.lblTitle.innerHTML = cfg.Texts.Chat;
                cfg.lblTitle.className = "titleChatNormal";
            }
            cfg.Minimized = true;
        }
    };

    var CreateMessageDOM = function (message, selfMessage, showUserName) {
        var divMessageRow = document.createElement("DIV");
        if (selfMessage) {
            divMessageRow.className = "selfMessageRow";
        } else {
            divMessageRow.className = "messageRow";
        }

        var divMessage = document.createElement("DIV");
        divMessage.className = "message";
        divMessageRow.appendChild(divMessage);

        if (showUserName) {
            var divUser = document.createElement("DIV");
            divUser.className = "user";
            divUser.innerHTML = escapeHTML(message.UserName);
            divMessage.appendChild(divUser);
        }

        var text = message.Text;

        var divText = document.createElement("DIV");
        divText.className = "text";
        divText.innerHTML = escapeHTML(text);
        divMessage.appendChild(divText);

        divMessage.title = new Date(message.Date);

        return divMessageRow;
    };

    var RequestChatData = function () {
        var ReciveChatData = function (responseText) {
            // Mark as connected
            if (cfg.Connected === false) {
                if (cfg.Minimized) {
                    cfg.lblTitle.innerHTML = cfg.Texts.Chat;
                } else {
                    cfg.lblTitle.innerHTML = cfg.Texts.Close;
                }
                cfg.lblTitle.className = "titleChatNormal";
                cfg.txtText.disabled = false;
                cfg.btnSend.disabled = false;
            }
            cfg.Connected = true;

            recvMsgs = JSON.parse(responseText);
            if (recvMsgs) {
                var msgCount = 0;
                var scrollChat = false;
                var scrollVisible = cfg.divChat.scrollHeight - cfg.divChat.offsetHeight;
                if (cfg.Minimized === false && cfg.divChat.scrollTop > scrollVisible) {
                    scrollChat = true;
                }

                var frag = document.createDocumentFragment();
                for (var i = 0, n = recvMsgs.length; i < n; i++) {
                    var msg = recvMsgs[i];
                    if (cfg.IDMessage < msg.IDMessage) {
                        cfg.IDMessage = msg.IDMessage;
                        var elemMessage = CreateMessageDOM(msg,
                            msg.UserName === cfg.UserName,
                            cfg.LastUser !== msg.UserName);
                        cfg.LastUser = msg.UserName;
                        frag.appendChild(elemMessage);
                        msgCount++;
                    }
                }
                cfg.divChat.appendChild(frag);
                if (scrollChat) {
                    cfg.divChat.scrollTop = cfg.divChat.scrollHeight;
                }
                if (cfg.Minimized && cfg.FirstMessages === false && msgCount > 0) {
                    cfg.lblTitle.innerHTML = cfg.Texts.NewMessages;
                    cfg.lblTitle.className = "titleChatAlert";
                }
            }

            cfg.FirstMessages = false;

            // Reset pool
            window.setTimeout(function () {
                RequestChatData();
            }, 20);
        };
        var ErrorChatData = function () {
            // Mark as disconnected
            cfg.lblTitle.innerHTML = cfg.Texts.Disconnected;
            cfg.lblTitle.className = "titleChatDisconnected";
            cfg.txtText.disabled = true;
            cfg.btnSend.disabled = true;
            cfg.Connected = false;

            cfg.FirstMessages = false;

            // Retry
            window.setTimeout(function () {
                RequestChatData();
            }, 5000);
        };

        // Pool data
        var isImmediate = cfg.FirstMessages || cfg.Connected === false;
        var data = {
            "IDMessageBoard": cfg.IDMessageBoard,
            "IDMessage": cfg.IDMessage,
            "TimePoolData": isImmediate ? "0" : String(cfg.TimePoolData),
            "TimeStamp": new Date().getTime()
        };
        SendRequest(cfg.ServiceUrl, data, ReciveChatData, ErrorChatData);
    };
    RequestChatData();
}

function SendChat(cfg) {
    cfg.txtText = GetElement(cfg.txtText);

    if (cfg.txtText.value.trim() === "") {
        return;
    }

    // Send data
    var data = {
        "Text": cfg.txtText.value,
        "IDMessageBoard": cfg.IDMessageBoard,
        "UserName": cfg.UserName,
        "TimeStamp": new Date().getTime()
    };
    SendData(cfg.ServiceUrl, data, null, null);

    cfg.txtText.value = "";
    cfg.txtText.focus();
}