/* CodeQ: an online programming tutor.
   Copyright (C) 2015 UL FRI

This program is free software: you can redistribute it and/or modify it under
the terms of the GNU Affero General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option) any
later version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
details.

You should have received a copy of the GNU Affero General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */

/**
 * Created by robert on 9/15/15.
 *
 */

(function() {
    "use strict";
    codeq.makeStateMachine = function (def) {
        var currState = null;
        return {
            'transition': function (name) {
                var newState = def[name];
                if (!newState) {
                    codeq.log.error('Cannot transition to state ' + name + ': it is not defined');
                    return;
                }
                if (newState === currState) {
                    codeq.log.info('Will not transition between identical states: ' + name);
                    return;
                }
                if (currState !== null) currState.exit();
                currState = newState;
                currState.enter.apply(currState, Array.prototype.slice.apply(arguments, [1]));
            },
            'destroy': function () {
                if (currState !== null) currState.exit();
                currState = null;
            },
            'register': function (name, state) {
                if (name in def) codeq.log.error('The state ' + name + ' is already registered, overriding');
                def[name] = state;
            }
        }
    };


    //the global state machine is a bit different - so it'll be implemented here
    var makeGlobalStateMachine = function (def) {
        var currState = null,
            waitingState = null; // state hidden with a modal form
        var stateChangeFun = function historyStateChangeHandler() {
            var historyState = History.getState();
            codeq.globalStateMachine.actualTransition.apply(codeq.globalStateMachine, $.merge([historyState.data.state] ,historyState.data.params));
        };
        History.Adapter.bind(window, 'statechange', stateChangeFun);
        //prepare the history state change listener
        return {
            'transition': function (name) {
                var newState = def[name];
                if (!newState) {
                    codeq.log.error('Cannot transition to state ' + name + ': it is not defined');
                    return;
                }
                if (newState === currState) {
                    codeq.log.info('Will not transition between identical states: ' + name);
                    return;
                }

                if(History.getState().data.state === name) codeq.globalStateMachine.actualTransition.apply(codeq.globalStateMachine,Array.prototype.slice.apply(arguments, [0]));//special case which happens if the user refreshes while in the login screen (history state doesn't change because it goes from login to login and the above listener doesn't trigger)
                try {
                    History.pushState({'state': name, 'params': Array.prototype.slice.apply(arguments, [1])}, 'CodeQ', '?s=' + name);
                }
                catch (e) {
                    codeq.log.error('init: History.pushState() failed for new state ' + name+'. Error:'+e, e);
                }
            },
            'destroy': function () {
                var i;
                if (currState) currState.exit();
                currState = null;
                if (waitingState) waitingState.exit();
                waitingState = null;
                History.Adapter.unbind(window, 'statechange', stateChangeFun);
            },
            'register': function (name, state, props) {
                if (name in def) codeq.log.error('The state ' + name + ' is already registered, overriding');
                def[name] = state;
            },
            'actualTransition': function (name) {
                //check if we are logged in - if we aren't we will always transition to the login state
                if(!codeq.comms.getSid() && name !== "signup" && name !== "aailogin"){//we can of course enter the signup/aailogin state even if not logged in
                    name = 'login';//this will cause the following code to transition to the login state instead of the original one given
                }

                var newState = def[name];//if the newState is not the same as the old or if it doesn't exist at all is already checked at this point
                if (currState) {
                    if (newState.isModal) {
                        if (currState.isModal) currState.exit();
                        else {
                            waitingState = currState;
                            waitingState.jqScreen.css('display', 'none');
                        }
                        currState = newState;
                        currState.enter.apply(currState, Array.prototype.slice.apply(arguments, [1]));
                    }
                    else {
                        currState.exit();
                        currState = newState;
                        if (waitingState === newState) {
                            waitingState.jqScreen.css('display', '');
                            waitingState = null;
                        }
                        else {
                            if (waitingState) {
                                waitingState.exit();
                                waitingState = null;
                            }
                            currState.enter.apply(currState, Array.prototype.slice.apply(arguments, [1]));
                        }
                    }
                }
                else {
                    currState = newState;
                    currState.enter.apply(currState, Array.prototype.slice.apply(arguments, [1]));
                }
            }
        }
    };
    codeq.globalStateMachine = makeGlobalStateMachine({});

    //setup all the buttons in the banner
    $('#navigation-home').on('click', function(e){
        codeq.globalStateMachine.transition('language');
        e.preventDefault();
    });
    $('#navigation-problem_list').on('click', function(e){
        codeq.globalStateMachine.transition('problem_list');
        e.preventDefault();
    });
    $('#navigation-python').on('click', function(e){
        codeq.globalStateMachine.transition('python');
        e.preventDefault();
    });
    $('#navigation-prolog').on('click', function(e){
        codeq.globalStateMachine.transition('prolog');
        e.preventDefault();
    });
    $('#navigation-robot').on('click', function(e){
        codeq.globalStateMachine.transition('robot');
        e.preventDefault();
    });
    $('#navigation-logout').on('click', function(e){

        codeq.comms.logout()
            .then(function (data) {
                codeq.comms.disconnect();
            })
            .fail(function (reason) {
                codeq.log.error('Logout failed: ' + reason);
            })
            .done();

        /*leaving this here if we later decide to enable saml_logout
        if(codeq.samlLogin){
            codeq.comms.samlLogout()
                .then(function (data) {
                    console.log(data);
                    codeq.comms.disconnect();
                })
                .fail(function (reason) {
                    console.log(reason);
                })
                .done();
        }else{
            codeq.comms.logout()
                .then(function (data) {
                    console.log(data);
                    codeq.comms.disconnect();
                })
                .fail(function (reason) {
                    console.log(reason);
                })
                .done();
        }*/

        codeq.globalStateMachine.transition('login');

        //codeq.globalStateMachine.transition('login');
        e.preventDefault();//prevent this since we'll trigger a page reload otherwise
    });
    $('#navigation-profile').on('click', function(e){
        codeq.globalStateMachine.transition('profile');
        e.preventDefault();//prevent this since we'll trigger a page reload otherwise
    });
    $('#navigation-about').on('click', function(e){
        codeq.globalStateMachine.transition('about');
        e.preventDefault();//prevent this since we'll trigger a page reload otherwise
    });
    $('#navigation-change-password').on('click', function(e){
        codeq.globalStateMachine.transition('changePassword');
        e.preventDefault();//prevent this since we'll trigger a page reload otherwise
    });
    $('#navigation-settings').on('click',function(e){
        codeq.globalStateMachine.transition('settings');
        e.preventDefault();
    });

})();