/**
 * Created by robert on 9/18/15.
 */

(function(){
    codeq.globalStateMachine.register('language',{
        'enter': function(){
            $('#disabled').css('display', '');
            $('#disabled').css('cursor', 'wait');
            codeq.comms.send({'action': 'list_problems'})//currently problem list and the actual login are still in the same state
                .then(
                function success(data) {
                    var i, groups, group, problems, problem, first_group,
                        jqGroup = $('#problem_group'),
                        jqProblems = $('#problems'),
                        html = [],
                        mapping = {},
                        onGroupChange = function () {
                            var problems = mapping[jqGroup.val()],
                                html = [],
                                i, p;
                            if (problems) {
                                for (i = 0; i < problems.length; i++) {
                                    p = problems[i];
                                    html.push('<option value="', p.identifier, '">', p.name, '</option>\n')
                                }
                            }
                            jqProblems.html(html.join(''));
                        };

                    if (data && (data.code === 0)) {
                        $('#disabled').css('display', 'none');
                        groups = data.problems;
                        for (i = 0; i < groups.length; i++) {
                            group = groups[i];
                            var identifier = group.identifier.language + '/' + group.identifier.group;
                            var name = group.name.language + ': ' + group.name.group;
                            html.push('<option value="', identifier, '">', name, '</option>\n');
                            mapping[identifier] = group.problems;
                        }
                        jqGroup.html(html.join(''));
                        first_group = html[1];
                        html = null;

                        jqGroup.on('click', onGroupChange);
                        jqGroup.val(first_group);
                        onGroupChange();

                        $("#submit_problem").on('click', function(){
                            var identifier = $('#problem_group').val().split('/'),
                                problem = $('#problems').val();
                            if (identifier.length < 2) alert('Choose a problem group');
                            else if (!problem) alert('Choose a problem');
                            else {
                                $('#disabled').css('display', '');
                                codeq.comms.getProblem(identifier[0], identifier[1], problem)
                                    .then(function (data) {
                                        if (data.code !== 0) throw new Error('Failed to obtain problem data, code: ' + data.code + ', message: ' + data.message);
                                        $('#disabled').css('display', 'none');
                                        switch (identifier[0]) {
                                            case 'prolog':
                                                codeq.globalStateMachine.transition('prolog', data);
                                                break;
                                            case 'python':
                                                codeq.globalStateMachine.transition('python', data);
                                                break;
                                            default:
                                                alert('Unknown language: ' + identifier[0]);
                                                break;
                                        }
                                    })
                                    .fail(function (reason) {
                                        $('#disabled').css('display', 'none');
                                        codeq.log.error('Getting problem definitions failed: ' + reason, reason);
                                        alert('Getting problem definitions failed: ' + reason);
                                    })
                                    .done();
                            }
                        });
                        $('#screen_language').css('display', '');
                    }
                    else {
                        $('#disabled').css('cursor', '');
                        alert('Obtaining list of problems failed: code=' + data.code + ', reason=' + data.message);
                    }
                },

                function failure(reason) {
                    $('#disabled').css('cursor', '');
                    alert('Request to obtain list of problems failed: ' + reason);
                }
            ).done();
        },
        'exit' : function(){
            $('#problem_group').off();
            $("#submit_problem").off();
            $("#problem_group option").remove();//empty the selects
            $("#problems option").remove();
            $("#screen_language").css('display', 'none');
        }
    });
})();