/**
 * Backend Customers javasript namespace. Contains the main functionality 
 * of the backend customers page. If you need to use this namespace in a 
 * different page, do not bind the default event handlers during initialization.
 *
 * @namespace BackendCustomers
 */
var BackendCustomers = {
    /**
     * The page helper contains methods that implement each record type functionality 
     * (for now there is only the CustomersHelper).
     * 
     * @type {object{
     */
    helper: {},
            
	/**
	 * This method initializes the backend customers page. If you use this namespace
	 * in a different page do not use this method. 
	 * 
	 * @param {bool} defaultEventHandlers (OPTIONAL = false) Whether to bind the default 
	 * event handlers or not.  
	 */
	initialize: function(defaultEventHandlers) {
		if (defaultEventHandlers == undefined) defaultEventHandlers = false; 
		
        BackendCustomers.helper = new CustomersHelper();
		BackendCustomers.helper.resetForm();
		BackendCustomers.helper.filter('');
        
        $('#filter-customers .results').jScrollPane();
        $('#customer-appointments').jScrollPane();
        
		if (defaultEventHandlers) {
			BackendCustomers.bindEventHandlers();
		}
	},
    
    /**
     * Default event handlers declaration for backend customers page.
     */
	bindEventHandlers: function() {
        CustomersHelper.prototype.bindEventHandlers();
	}
};

/**
 * This class contains the methods that are used in the backend customers page.
 * 
 * @class CustomersHelper
 */
var CustomersHelper = function() {
    this.filterResults = {};
};

/**
 * Binds the default event handlers of the backend customers page.
 */
CustomersHelper.prototype.bindEventHandlers = function() {
    /**
     * Event: Filter Customers Form "Submit"
     */
    $('#filter-customers form').submit(function() {
        event.preventDefault();
        var key = $('#filter-customers .key').val();
        $('#filter-customers .selected-row').removeClass('selected-row');
        BackendCustomers.helper.resetForm();
        BackendCustomers.helper.filter(key);
    });
    
    /**
     * Event: Filter Customers Clear Button "Click"
     */
    $('#filter-customers .clear').click(function() {
        $('#filter-customers .key').val('');
        BackendCustomers.helper.filter('');
    });
    
    /**
     * Event: Customer Row "Click"
     * 
     * Display the customer data of the selected row.
     */
    $(document).on('click', '.customer-row', function() {
        if ($('#filter-customers .filter').prop('disabled')) {
            return; // Do nothing when user edits a customer record.
        }
        
        var customerId = $(this).attr('data-id');
        var customer = {};
        $.each(BackendCustomers.helper.filterResults, function(index, item) {
            if (item.id == customerId) {
                customer = item;
                return false;
            }
        });
        
        BackendCustomers.helper.display(customer);
        $('#filter-customers .selected-row').removeClass('selected-row');
        $(this).addClass('selected-row');
        $('#edit-customer, #delete-customer').prop('disabled', false);
    });

    /**
     * Event: Appointment Row "Click"
     * 
     * Display appointment data of the selected row.
     */
    $(document).on('click', '.appointment-row', function() {
        $('#customer-appointments .selected-row').removeClass('selected-row');
        $(this).addClass('selected-row');

        var customerId = $('#filter-customers .selected-row').attr('data-id');
        var appointmentId = $(this).attr('data-id');
        var appointment = {};

        $.each(BackendCustomers.helper.filterResults, function(index, c) {
            if (c.id === customerId) {
                $.each(c.appointments, function(index, a) {
                    if (a.id == appointmentId) {
                        appointment = a;
                        return false;
                    }
                });
                return false;
            }
        });

        BackendCustomers.helper.displayAppointment(appointment);
    });

    /**
     * Event: Add Customer Button "Click"
     */
    $('#add-customer').click(function() {
        BackendCustomers.helper.resetForm();
        $('#add-edit-delete-group').hide();
        $('#save-cancel-group').show();
        $('.details').find('input, textarea').prop('readonly', false);

        $('#filter-customers button').prop('disabled', true);
        $('#filter-customers .results').css('color', '#AAA');
    });

    /**
     * Event: Edit Customer Button "Click"
     */
    $('#edit-customer').click(function() {
        $('.details').find('input, textarea').prop('readonly', false);
        $('#add-edit-delete-group').hide();
        $('#save-cancel-group').show();

        $('#filter-customers button').prop('disabled', true);
        $('#filter-customers .results').css('color', '#AAA');
    });

    /**
     * Event: Cancel Customer Add/Edit Operation Button "Click"
     */
    $('#cancel-customer').click(function() {
        var id = $('#customer-id').val();
        BackendCustomers.helper.resetForm();
        if (id != '') {
            BackendCustomers.helper.select(id, true);
        }
    });

    /**
     * Event: Save Add/Edit Customer Operation "Click"
     */
    $('#save-customer').click(function() {
        var customer = {
            'first_name': $('#first-name').val(),
            'last_name': $('#last-name').val(),
            'email': $('#email').val(),
            'phone_number': $('#phone-number').val(),
            'address': $('#address').val(),
            'city': $('#city').val(),
            'zip_code': $('#zip-code').val(),
            'notes': $('#notes').val()
        };

        if ($('#customer-id').val() != '') {
            customer.id = $('#customer-id').val();
        }
        
        if (!BackendCustomers.helper.validate(customer)) return;
            
        BackendCustomers.helper.save(customer);
    });

    /**
     * Event: Delete Customer Button "Click"
     */
    $('#delete-customer').click(function() {
        var customerId = $('#customer-id').val();
        
        var messageBtns = {
            'Delete': function() {        
                BackendCustomers.helper.delete(customerId);
                $('#message_box').dialog('close');
            },

            'Cancel': function() {
                $('#message_box').dialog('close');
            }
        };

        GeneralFunctions.displayMessageBox('Delete Customer', 'Are you sure that you want '
                + 'to delete this customer? This action cannot be undone.', messageBtns);
    });
};

/**
 * Save a customer record to the database (via ajax post).
 * 
 * @param {object} customer Contains the customer data.
 */
CustomersHelper.prototype.save = function(customer) {
    var postUrl = GlobalVariables.baseUrl + 'backend_api/ajax_save_customer';
    var postData = { 'customer': JSON.stringify(customer) };
    
    $.post(postUrl, postData, function(response) {
        ///////////////////////////////////////////////////////////
        console.log('Save Customer Response:', response);
        ///////////////////////////////////////////////////////////
        
        if (!GeneralFunctions.handleAjaxExceptions(response)) return;
        
        Backend.displayNotification('Customer saved successfully!');
        BackendCustomers.helper.resetForm();
        $('#filter-customers .key').val('');
        BackendCustomers.helper.filter('', response.id, true);
    }, 'json');
};

/**
 * Delete a customer record from database.
 * 
 * @param {numeric} id Record id to be deleted. 
 */
CustomersHelper.prototype.delete = function(id) {
    var postUrl = GlobalVariables.baseUrl + 'backend_api/ajax_delete_customer';
    var postData = { 'customer_id': id };
    
    $.post(postUrl, postData, function(response) {
        ////////////////////////////////////////////////////
        //console.log('Delete customer response:', response);
        ////////////////////////////////////////////////////
        
        if (!GeneralFunctions.handleAjaxExceptions(response)) return;
        
        Backend.displayNotification('Customer deleted successfully!');
        BackendCustomers.helper.resetForm();
        BackendCustomers.helper.filter($('#filter-customers .key').val());
    }, 'json');
};

/**
 * Validate customer data before save (insert or update).
 * 
 * @param {object} customer Contains the customer data.
 */
CustomersHelper.prototype.validate = function(customer) {
    $('#form-message').hide();
    $('.required').css('border', '');
    
    try {
        // Validate required fields.
        var missingRequired = false;
        $('.required').each(function() {
            if ($(this).val() == '') {
                $(this).css('border', '2px solid red');
                missingRequired = true;
            }
        });
        if (missingRequired) {
            throw 'Fields with * are required!';
        }

        // Validate email address.
        if (!GeneralFunctions.validateEmail($('#email').val())) {
            $('#email').css('border', '2px solid red');
            throw 'Invalid email address!';
        }

        return true;

    } catch(exc) {
        $('#form-message').text(exc).show();
        return false;
    }
};

/**
 * Bring the customer form back to its initial state.
 */
CustomersHelper.prototype.resetForm = function() {
    $('.details').find('input, textarea').val(''); 
    $('.details').find('input, textarea').prop('readonly', true); 
    
    $('#customer-appointments').html('');
    $('#appointment-details').html('');
    $('#edit-customer, #delete-customer').prop('disabled', true);
    $('#add-edit-delete-group').show();
    $('#save-cancel-group').hide();
    
    $('.details .required').css('border', '');
    $('.details #form-message').hide();
    
    $('#filter-customers button').prop('disabled', false);
    $('#filter-customers .selected-row').removeClass('selected-row');
    $('#filter-customers .results').css('color', '');
};

/**
 * Display a customer record into the form.
 * 
 * @param {object} customer Contains the customer record data.
 */
CustomersHelper.prototype.display = function(customer) {
    $('#customer-id').val(customer.id);
    $('#first-name').val(customer.first_name);
    $('#last-name').val(customer.last_name);
    $('#email').val(customer.email);
    $('#phone-number').val(customer.phone_number);
    $('#address').val(customer.address);
    $('#city').val(customer.city);
    $('#zip-code').val(customer.zip_code);
    $('#notes').val(customer.notes);

    $('#customer-appointments').data('jsp').destroy();
    $('#customer-appointments').empty();
    $.each(customer.appointments, function(index, appointment) {
        var start = Date.parse(appointment.start_datetime).toString('dd/MM/yyyy HH:mm');
        var end = Date.parse(appointment.end_datetime).toString('dd/MM/yyyy HH:mm');
        var html = 
                '<div class="appointment-row" data-id="' + appointment.id + '">' + 
                    start + ' - ' + end + '<br>' +
                    appointment.service.name + ', ' + 
                    appointment.provider.first_name + ' ' + appointment.provider.last_name +
                '</div>';   
        $('#customer-appointments').append(html);
    });
    $('#customer-appointments').jScrollPane({ mouseWheelSpeed: 70 });
};

/**
 * Filter customer records.
 * 
 * @param {string} key This key string is used to filter the customer records.
 * @param {numeric} selectId (OPTIONAL = undefined) If set then after the filter 
 * operation the record with the given id will be selected (but not displayed).
 * @param {bool} display (OPTIONAL = false) If true then the selected record will
 * be displayed on the form.
 */
CustomersHelper.prototype.filter = function(key, selectId, display) {
    if (display == undefined) display = false;
    
    var postUrl = GlobalVariables.baseUrl + 'backend_api/ajax_filter_customers';
    var postData = { 'key': key };
    
    $.post(postUrl, postData, function(response) {
        ///////////////////////////////////////////////////////
        console.log('Filter Customers Response:', response);
        ///////////////////////////////////////////////////////
        
        if (!GeneralFunctions.handleAjaxExceptions(response)) return;
        
        BackendCustomers.helper.filterResults = response;
        
        $('#filter-customers .results').data('jsp').destroy(); 
        $('#filter-customers .results').html('');
        $.each(response, function(index, customer) {
           var html = BackendCustomers.helper.getFilterHtml(customer);
           $('#filter-customers .results').append(html);
        });
        $('#filter-customers .results').jScrollPane({ mouseWheelSpeed: 70 });
        
        if (response.length == 0) {
            $('#filter-customers .results').html('<em>No records found...</em>');
        }
        
        if (selectId != undefined) {
            BackendCustomers.helper.select(selectId, display);
        }
        
    }, 'json');
};

/**
 * Get the filter results row html code.
 * 
 * @param {object} customer Contains the customer data.
 * @return {string} Returns the record html code.
 */
CustomersHelper.prototype.getFilterHtml = function(customer) {
    var html = 
            '<div class="customer-row" data-id="' + customer.id + '">' +
                '<strong>' + 
                    customer.first_name + ' ' + customer.last_name + 
                '</strong><br>' + 
                '<span>' + customer.email + '</span> | ' + 
                '<span>' + customer.phone_number + '</span>' + 
            '</div><hr>';
    
    return html;
};
 
/**
 * Select a specific record from the current filter results. If the customer id does not exist 
 * in the list then no record will be selected. 
 * 
 * @param {numeric} id The record id to be selected from the filter results.
 * @param {bool} display (OPTIONAL = false) If true then the method will display the record
 * on the form.
 * 
 * @task The selected row must always be visible (even if a vertical scroll bar is used to 
 * navigate through the filter results).
 */
CustomersHelper.prototype.select = function(id, display) {
    if (display == undefined) display = false;
    
    $('#filter-customers .selected-row').removeClass('selected-row');
    
    $('#filter-customers .customer-row').each(function() {
        if ($(this).attr('data-id') == id) {
            $(this).addClass('selected-row');
            return false;
        }
    });
    
    if (display) { 
        $.each(BackendCustomers.helper.filterResults, function(index, customer) {
            if (customer.id == id) {
                BackendCustomers.helper.display(customer);
                $('#edit-customer, #delete-customer').prop('disabled', false);
                return false;
            }
        });
    }
}; 
 
/**
 * Display appointment details on customers backend page.
 * 
 * @param {object} appointment Appointment data
 */
CustomersHelper.prototype.displayAppointment = function(appointment) {
    var start = Date.parse(appointment.start_datetime).toString('dd/MM/yyyy HH:mm');
    var end = Date.parse(appointment.end_datetime).toString('dd/MM/yyyy HH:mm');

    var html = 
            '<div>' + 
                '<strong>' + appointment.service.name + '</strong><br>' + 
                appointment.provider.first_name + ' ' + appointment.provider.last_name + '<br>' +
                start + ' - ' + end + '<br>' +
            '</div>';

    $('#appointment-details').html(html);
};