MainView.java

    /*
     * Program developed by Hassan Althaf.
     * Copyright © 2015, Hassan Althaf.
     * Website: http://hassanalthaf.com
     */
    package com.HassanAlthaf.StockControlSystem.View;

    import com.HassanAlthaf.StockControlSystem.Stocks.StockController;
    import com.HassanAlthaf.StockControlSystem.Stocks.StockItem;
    import com.HassanAlthaf.StockControlSystem.Users.User;
    import com.HassanAlthaf.StockControlSystem.Users.UserController;
    import java.io.IOException;
    import java.net.URL;
    import java.sql.SQLException;
    import java.util.ArrayList;
    import java.util.ResourceBundle;
    import javafx.collections.FXCollections;
    import javafx.collections.ObservableList;
    import javafx.event.ActionEvent;
    import javafx.fxml.FXML;
    import javafx.fxml.FXMLLoader;
    import javafx.fxml.Initializable;
    import javafx.scene.Parent;
    import javafx.scene.Scene;
    import javafx.scene.control.Button;
    import javafx.scene.control.Label;
    import javafx.scene.control.Menu;
    import javafx.scene.control.MenuItem;
    import javafx.scene.control.TableColumn;
    import javafx.scene.control.TableView;
    import javafx.scene.control.TextField;
    import javafx.scene.control.cell.PropertyValueFactory;
    import javafx.scene.layout.AnchorPane;
    import javafx.scene.text.Text;
    import javafx.stage.Stage;

    /**
     *
     * @author hassan
     */
    public class MainView implements Initializable {

        @FXML
        private Parent mainWindow;

        @FXML
        private AnchorPane main;

        @FXML
        private AnchorPane about;

        @FXML
        private AnchorPane addInventoryItem;

        @FXML
        private AnchorPane listInventory;

        @FXML
        private AnchorPane listUsers;

        private AnchorPane activePage;

        @FXML
        private TextField productNameField;

        @FXML
        private TextField availableQuantityField;

        @FXML
        private TextField unitPriceField;

        @FXML
        private TextField reorderLevelField;

        private final StockController stockController;

        @FXML
        private Text addItemErrors;

        @FXML
        private TableView<StockItem> stockList;

        @FXML
        private TableColumn productNameColumn;

        @FXML
        private TableColumn unitPriceColumn;

        @FXML
        private TableColumn availableQuantityColumn;

        @FXML
        private TableColumn reorderLevelColumn;

        @FXML
        private TableColumn totalValueColumn;

        @FXML
        private TableView<User> usersList;

        @FXML
        private TableColumn usernameColumn;

        @FXML
        private TableColumn rankColumn;

        @FXML
        private Label totalStockValueLabel;

        private ObservableList<StockItem> stockItemData;

        private ObservableList<User> userListData;

        private UserController userController;

        @FXML
        private Menu userMenu;

        @FXML
        private MenuItem addStockMenuItem;

        @FXML
        private Button deleteStockItemButton;

        public MainView() {
            this.stockController = new StockController();
        }

        public void setUserController(UserController userController) {
            this.userController = userController;
        }

        public void show(Parent loginWindow) throws IOException, SQLException {
            Scene scene  = new Scene(this.mainWindow);

            Stage stage = new Stage();

            stage.setScene(scene);
            stage.setTitle("Stock Control System");
            stage.setResizable(false);
            stage.show();

            this.updateViewForUser();
            this.initializeStats();

            Stage loginStage = (Stage) loginWindow.getScene().getWindow();
            loginStage.close();

            this.activePage = this.main;
        }

        public void menuClick(ActionEvent event) throws SQLException, IOException {
            Object source = event.getSource();

            String id = null;

            if (source instanceof MenuItem) {
                MenuItem clickedItem = (MenuItem) source;
                id = clickedItem.getId();
            }

            this.authenticateAccess();
            this.updateViewForUser();

            if (id.equals("aboutMenuItem")) {
                this.activePage.setOpacity(0);
                this.about.toFront();
                this.about.setOpacity(1);
                this.activePage = this.about;
            } else if (id.equals("homeMenuItem")) {
                this.activePage.setOpacity(0);
                this.main.toFront();
                this.main.setOpacity(1);
                this.activePage = this.main;
            } else if (id.equals("addStockMenuItem")) {
                this.authenticateAdminRights();
                this.activePage.setOpacity(0);
                this.addInventoryItem.toFront();
                this.addInventoryItem.setOpacity(1);
                this.activePage = this.addInventoryItem;
            } else if (id.equals("listStocksMenuItem")) {
                this.activePage.setOpacity(0);
                this.listInventory.toFront();
                this.populateStocksList();
                this.listInventory.setOpacity(1);
                this.activePage = this.listInventory;
            } else if (id.equals("loadUsersList")) {
                this.authenticateAdminRights();
                this.activePage.setOpacity(0);
                this.listUsers.toFront();
                this.populateUsersList();
                this.listUsers.setOpacity(1);
                this.activePage = this.listUsers;
            }
        }

        public void authenticateAccess() throws IOException, SQLException {
            this.userController.updateLoggedInUser();

            if(this.userController.userIsDisabled()) {
                this.logUserOut();
            }
        }

        public void authenticateAdminRights() throws IOException, SQLException {
            this.userController.updateLoggedInUser();

            if(!this.userController.isAdmin()) {
                this.logUserOut();
            }
        }

        public void addStockItem(ActionEvent event) throws SQLException, IOException {
            this.authenticateAdminRights();

            boolean response = this.stockController.addStockItem(
                    this.productNameField.getText(),
                    this.availableQuantityField.getText(),
                    this.unitPriceField.getText(),
                    this.reorderLevelField.getText()
            );

            if (response == false) {
                ArrayList<String> errors = this.stockController.getReturnMessages();
                String text = "";

                for (String line : errors) {
                    text = text + line + "\n";
                }

                text = text.substring(0, text.length() - 1);

                this.addItemErrors.setText(text);
            } else {
                this.initializeStats();
                this.addItemErrors.setText("Successfully added!");
            }
        }

        public void populateStocksList() throws IOException, SQLException {
            ArrayList<StockItem> stockItems = null;

            this.authenticateAccess();

            try {
                stockItems = this.stockController.fetchAllStockItems();
            } catch(SQLException exception) {
                System.out.println("Failed");
            }

            this.stockItemData = FXCollections.observableArrayList(stockItems);

            this.productNameColumn.setCellValueFactory(
                    new PropertyValueFactory<>("productName")
            );

            this.availableQuantityColumn.setCellValueFactory(
                    new PropertyValueFactory<>("availableQuantity")
            );

            this.unitPriceColumn.setCellValueFactory(
                    new PropertyValueFactory<>("unitPrice")
            );

            this.reorderLevelColumn.setCellValueFactory(
                    new PropertyValueFactory<>("reorderLevel")
            );

            this.totalValueColumn.setCellValueFactory(
                    new PropertyValueFactory<>("totalValue")
            );

            this.stockList.setItems(this.stockItemData);
        }

        public void populateUsersList() throws IOException, SQLException {
            this.authenticateAdminRights();

            ArrayList<User> usersList = null;

            try {
                usersList = this.userController.fetchAllUsers();
            } catch(SQLException exception) {
                System.out.println("Failed");
            }

            this.userListData = FXCollections.observableArrayList(usersList);

            this.usernameColumn.setCellValueFactory(
                    new PropertyValueFactory<>("username")
            );

            this.rankColumn.setCellValueFactory(
                    new PropertyValueFactory<>("rank")
            );

            this.usersList.setItems(this.userListData);
        }

        public void initializeStats() throws IOException, SQLException {
            this.authenticateAccess();
            this.setTotalStockValueLabel();
        }

        public void setTotalStockValueLabel() {
            ArrayList<StockItem> stockItems = null;

            try {
                stockItems = this.stockController.fetchAllStockItems();
            } catch(Exception exception) {
                System.out.println(exception);
            }

            Double totalStockValue = 0.0;

            for(StockItem stockItem : stockItems) {
                totalStockValue = totalStockValue + Double.parseDouble(stockItem.getTotalValue());
            }

            this.totalStockValueLabel.setText(String.format("%.2f", totalStockValue));
        }

        public void editStockItem(ActionEvent event) throws IOException, SQLException {
            this.authenticateAccess();
            if(this.stockList.getSelectionModel().getSelectedItem() != null) {
                FXMLLoader loader = new FXMLLoader(getClass().getResource("EditStockItemDialog.fxml"));
                Parent editStockItemDialog = loader.load();
                EditStockItemDialogView editStockItemDialogView = loader.getController();

                editStockItemDialogView.setStockItemObject(this.stockList.getSelectionModel().getSelectedItem());
                editStockItemDialogView.setStockController(this.stockController);
                editStockItemDialogView.setMainView(this);
                editStockItemDialogView.show();
            }

        }

        public void deleteStockItem(ActionEvent event) throws SQLException, IOException {
            this.authenticateAdminRights();

            if(this.stockList.getSelectionModel().getSelectedItem() != null) {
                this.stockController.removeStockItem(this.stockList.getSelectionModel().getSelectedItem().getID());
            }

            this.initializeStats();
            this.populateStocksList();
        }

        public void logoutUser(ActionEvent event) throws IOException {
            this.logUserOut();
        }

        public void logUserOut() throws IOException {
            this.userController.logout();

            FXMLLoader loader = new FXMLLoader(getClass().getResource("LoginWindow.fxml"));
            Parent loginWindow = loader.load();
            LoginWindowView  loginWindowView = loader.getController();

            loginWindowView.show(this.mainWindow);
        }

        public void addUser(ActionEvent event) throws IOException, SQLException {
            this.authenticateAdminRights();

            FXMLLoader loader = new FXMLLoader(getClass().getResource("AddUserDialog.fxml"));
            Parent addUserDialog = loader.load();
            AddUserDialogView addUserDialogView = loader.getController();

            addUserDialogView.setMainView(this);
            addUserDialogView.setUserController(this.userController);
            addUserDialogView.show();
        }

        public void editUser(ActionEvent event) throws IOException, SQLException {
            this.authenticateAdminRights();

            if(this.usersList.getSelectionModel().getSelectedItem() != null) {
                FXMLLoader loader = new FXMLLoader(getClass().getResource("EditUserDialog.fxml"));
                Parent editUserDialog = loader.load();
                EditUserDialogView editUserDialogView = loader.getController();

                editUserDialogView.setMainView(this);
                editUserDialogView.setUserController(this.userController);
                editUserDialogView.setUserEntity(this.usersList.getSelectionModel().getSelectedItem());
                editUserDialogView.show();
            }
        }

        public void deleteUser(ActionEvent event) throws SQLException, IOException {
            this.authenticateAdminRights();

            if(this.usersList.getSelectionModel().getSelectedItem() != null) {
                this.userController.deleteUser(this.usersList.getSelectionModel().getSelectedItem().getID());
            }

            this.populateUsersList();
        }

        public void updateViewForUser() throws IOException, SQLException {
            this.userController.updateLoggedInUser();

            int rank = userController.getLoggedInUser().getRank();

            if(rank == UserController.RANK_DISABLED_USER) {
                this.logUserOut();
            } else if(rank == UserController.RANK_REGULAR_USER) {
                this.userMenu.setDisable(true);
                this.addStockMenuItem.setDisable(true);
                this.deleteStockItemButton.setDisable(true);
            } else if(rank == UserController.RANK_ADMINISTRATOR) {
                this.userMenu.setDisable(false);
                this.addStockMenuItem.setDisable(false);
                this.deleteStockItemButton.setDisable(false);
            }
        }

        @Override
        public void initialize(URL url, ResourceBundle rb) {

        }
    }