(function () {

    Rakka.showLoginPanel = function () {
        var $area = Rakka.switchScreen();

        $area.append($.H1({}, "Login"));

        var fldUserID
            = $.INPUT({type: "text"});

        var fldPassword
            = $.INPUT({type: "password"});

        var btnLogin
            = $.INPUT({type: "button", value: "Login"});

        $(btnLogin)
            .click(function () {
                       login(fldUserID.value, fldPassword.value);
                   });

        var fldHandler = function (ev) {
                             if (ev.keyCode == 27) { // ESC
                                 Rakka.restoreScreen();
                                 return false;
                             }
                             else if (ev.keyCode == 13) { // CR
                                 login(fldUserID.value, fldPassword.value);
                                 return false;
                             }
                             else {
                                 return true;
                             }
        };
        $(fldUserID).keypress(fldHandler);
        $(fldPassword).keypress(fldHandler);

        var btnCancel
            = $.INPUT({type: "button", value: "Cancel"});

        $(btnCancel).click(function () {
            Rakka.restoreScreen();
        });

        var loginPanel
            = $.TABLE({className: "loginPanel"},
                      $.TBODY({},
                              $.TR({},
                                   $.TH({}, "User ID"),
                                   $.TD({}, fldUserID)
                                  ),
                              $.TR({},
                                   $.TH({}, "Password"),
                                   $.TD({}, fldPassword)
                                  ),
                              $.TR({},
                                   $.TH({}),
                                   $.TD({}, btnLogin, btnCancel)
                                  )
                             )
                     );

        $area.append(loginPanel);
        $(fldUserID).focus();
    };

    var login = function (userID, password) {
        $.ajax({
            type      : "GET",
            url       : Rakka.baseURI + "checkAuth",
            beforeSend: function (req) {
                req.setRequestHeader(
                    "Authorization",
                    "Basic " + Rakka.encodeBase64(userID + ":" + password));
            },
            success   : function () {
                document.cookie
                    = "rakkaLoginInfo="
                    + Rakka.encodeBase64(userID + ":" + password)
                    + ";max-age=31536000";
                updateLoginState();
                Rakka.restoreScreen();
            },
            error     : function (req) {
                if (req.status == 403) {
                    alert("Login failed: wrong ID or password");
                }
                else {
                    alert("Error: " + req.status + " " + req.statusText);
                }
            }
        });
    };

    var logout = function () {
        document.cookie = "rakkaLoginInfo=;max-age=0";
        updateLoginState();
        Rakka.restoreScreen();
    };

    var currentUserID;
    var currentPassword;

    var updateLoginState = function () {
        currentUserID   = null;
        currentPassword = null;

        var cookies = document.cookie.split(/;\s*/);
        $.each(cookies, function () {
            var m = this.match(/^([^=]*)=(.*)$/);
            if (m) {
                var key   = m[1];
                var value = m[2];

                if (key == "rakkaLoginInfo") {
                    m = Rakka.decodeBase64(value).match(/^([^:]*):(.*)$/);
                    if (m) {
                        currentUserID   = m[1];
                        currentPassword = m[2];
                    }
                }
            }
        });

        if (currentUserID != null) {
            /* ログイン中 */
            $("input.loginButton")
                .val("Logout [" + currentUserID + "]")
                .unbind("click")
                .click(function () {
                    logout();
                });

            $("input.newButton").attr({disabled: ""});

            $("input.editButton").attr({
                disabled: (Rakka.isSpecialPage ? "disabled" : "")
            });

            $("input.configButton").attr({
              disabled: ""
            });
        }
        else {
            /* ログインしてゐない */
            $("input.loginButton")
                .val("Login")
                .unbind("click")
                .click(Rakka.showLoginPanel);

            $("input.newButton").attr({
                disabled: (Rakka.isGlobalLocked ? "disabled" : "")
            });

            $("input.editButton").attr({
                disabled: (Rakka.isLocked || Rakka.isGlobalLocked || Rakka.isSpecialPage ? "disabled" : "")
            });

            $("input.configButton").attr({
                disabled: "disabled"
            });
        }
    };

    Rakka.setAuthorization = function (req) {
        if (Rakka.isLoggedIn()) {
            req.setRequestHeader(
                "Authorization",
                    "Basic " + Rakka.encodeBase64(currentUserID + ":" + currentPassword));
        }
    };

    Rakka.isLoggedIn = function () {
        return currentUserID != null;
    };

    $(document).ready(function () {
        updateLoginState();
    });

})();