package de.uniluebeck.mi.projmi6.controller;


import de.uniluebeck.mi.projmi6.db.DBHandler;
import de.uniluebeck.mi.projmi6.model.DiagArt;
import de.uniluebeck.mi.projmi6.model.Diagnose;
import de.uniluebeck.mi.projmi6.model.Icd10Code;
import de.uniluebeck.mi.projmi6.model.Mitarbeiter;
import de.uniluebeck.mi.projmi6.view.SelectKeyComboBoxListener;
import javafx.beans.property.ReadOnlyObjectProperty;
import javafx.beans.property.SimpleObjectProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.collections.transformation.FilteredList;
import javafx.fxml.FXML;
import javafx.scene.control.*;
import javafx.scene.layout.GridPane;

/**
 * Controller that mantains the diagnosis assigned to a case in the UI.
 *
 * @author Johannes
 *         Created by 631806 on 12.11.15.
 */
public class DiagnoseController {

    private final SimpleObjectProperty<ObservableList<Diagnose>> diagnosen = new SimpleObjectProperty<>();

    /**
     * Controller state definitions
     */
    public enum State {
        CREATE, EDIT, VIEW
    }

    /**
     * Current controllers state
     */
    private final SimpleObjectProperty<State> state = new SimpleObjectProperty<>(State.VIEW);

    @FXML
    private Button btnDiagAbort, btnDiagEdit, btnDiagSave, btnDiagCreate, btnDiagCancel;

    @FXML
    private final MainController mainController;

    @FXML
    private ListView<Diagnose> diagnoseList;
    @FXML
    private GridPane fields;
    @FXML
    private ComboBox<Mitarbeiter> diagDiagnoseArzt;
    @FXML
    private Label diagCreator, diagCreateTime, diagChanger, diagChangeTime;
    @FXML
    private TextArea diagFreitext;
    @FXML
    private ComboBox<DiagArt> diagDiagnoseArt;
    @FXML
    private ComboBox<Icd10Code> diagDiagnose;

    /**
     * Contructor.
     *
     * @param mainController The main controller that creates this instance.
     */
    public DiagnoseController(MainController mainController) {
        this.mainController = mainController;
    }

    /**
     * Getter for the {@link #diagnosenProperty()}.
     *
     * @return The list of diagnosis shown in the GUI. Might be null.
     */
    public ObservableList<Diagnose> getDiagnosen() {
        return diagnosen.get();
    }


    /**
     * Setter for the {@link #diagnosenProperty()}.
     *
     * @param diagnosen A observable list of diagnosis to be set.
     */
    public void setDiagnosen(ObservableList<Diagnose> diagnosen) {
        this.diagnosen.set(diagnosen);
    }

    /**
     * The diagnosis in this controller.
     *
     * @return A simple object property.
     */
    public SimpleObjectProperty<ObservableList<Diagnose>> diagnosenProperty() {
        return diagnosen;
    }

    /**
     * Getter for the state of this controller
     *
     * @return State.VIEW, State.EDIT or State.CREATE
     */
    public State getState() {
        return state.get();
    }

    /**
     * A property for the controllers state.
     */
    public ReadOnlyObjectProperty<State> stateProperty() {
        return state;
    }

    /**
     * FXMLLoaders initialize()-method.
     * See <a href="https://docs.oracle.com/javase/8/javafx/api/javafx/fxml/doc-files/introduction_to_fxml.html#controllers">Oracle FXML Introduction</a>
     */
    @FXML
    private void initialize() {
        initButtons();

        //Init diagnosis list view
        diagDiagnose.itemsProperty().bind(mainController.getStammdaten().icd10CodesProperty());
        new SelectKeyComboBoxListener(diagDiagnose);

        //init fields on the right
        diagDiagnoseArt.setItems(FXCollections.observableArrayList(DiagArt.values()));

        FilteredList<Mitarbeiter> mitarbeiterFilteredList = new FilteredList<Mitarbeiter>(mainController.getStammdaten().getMitarbeiter());
        mitarbeiterFilteredList.setPredicate(m -> !m.getNachname().equalsIgnoreCase("SYSTEM"));
        diagDiagnoseArzt.setItems(mitarbeiterFilteredList);

        diagnoseList.itemsProperty().bind(diagnosen);
        fields.disableProperty().bind(state.isEqualTo(State.VIEW));

        //Init the list view on the left.
        diagnoseList.getSelectionModel().setSelectionMode(SelectionMode.SINGLE);
        diagnoseList.disableProperty().bind(state.isNotEqualTo(State.VIEW));
        diagnoseList.getSelectionModel().selectedItemProperty().addListener((observable, oldValue, newValue) -> {
            if (newValue == null) {
                clearFields();
            } else {
                copyDiagnoseDataIntoFields(newValue);
            }
        });

        //React on state changes.
        state.addListener((observable, oldValue, newValue) -> {
            if (newValue == State.VIEW) {
                mainController.unlockFromEdit();
                Diagnose diagnose = diagnoseList.getSelectionModel().getSelectedItem();
                if (diagnose == null) {
                    clearFields();
                } else {
                    copyDiagnoseDataIntoFields(diagnose);
                }
            } else {
                mainController.lockForEdit(MainController.TabName.DIAGNOSE);
                if (newValue == State.CREATE) {
                    clearFields();
                    diagDiagnoseArzt.setValue(mainController.getCurrentMitarbeiter());
                }
            }
        });


    }

    /**
     * Bind button visibility to application state.
     */
    private void initButtons() {
        btnDiagCreate.disableProperty().bind(mainController.fallProperty().isNull());

        btnDiagEdit.disableProperty().bind(diagnoseList.getSelectionModel().selectedItemProperty().isNull());

        //btnDiagEdit.managedProperty().bind(state.isEqualTo(State.VIEW));
        //btnDiagEdit.visibleProperty().bind(btnDiagEdit.managedProperty());
        btnDiagEdit.setManaged(false);
        btnDiagEdit.setVisible(false);

        btnDiagSave.managedProperty().bind(state.isNotEqualTo(State.VIEW));
        btnDiagSave.visibleProperty().bind(btnDiagSave.managedProperty());

        btnDiagAbort.managedProperty().bind(btnDiagSave.managedProperty());
        btnDiagAbort.visibleProperty().bind(btnDiagSave.managedProperty());

    }

    /**
     * EventHandler for {@link #btnDiagEdit}.
     */
    @FXML
    private void clickedEdit() {
        state.set(State.EDIT);
    }

    /**
     * EventHandler for {@link #btnDiagAbort}.
     */
    @FXML
    private void clickedAbort() {
        state.set(State.VIEW);
    }

    /**
     * EventHandler for the {@link #btnDiagCreate}.
     */
    @FXML
    private void clickedDiagCreate() {
        this.state.set(State.CREATE);
    }

    /**
     * EventHandler for the {@link #btnDiagCancel}.
     */
    @FXML
    private void clickedDiagCancel() {

    }

    /**
     * EventHandler method for {@link #btnDiagSave}
     */
    @FXML
    void clickedDiagSave() {
        if (state.get() == State.CREATE) {
            //Create new diagnosis
            Diagnose diagnose = new Diagnose();
            copyFieldDataIntoDiagnose(diagnose);
            try {
                DBHandler.setDiagnose(diagnose);
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
        mainController.refreshCaseData();
        state.set(State.VIEW);
    }

    /**
     * Copy the object data into the fields.
     *
     * @param diagnose The object with the data.
     */
    private void copyDiagnoseDataIntoFields(Diagnose diagnose) {
        //Find the DiagnoseArzt by id.
        for (Mitarbeiter current : diagDiagnoseArzt.getItems()) {
            if (current.getMitarbID() == diagnose.getMitarbid()) {
                diagDiagnoseArzt.setValue(current);
                break;
            }
        }

        diagFreitext.setText(diagnose.getFreiText());
        diagDiagnoseArt.setValue(diagnose.getDiagArt());
        diagDiagnose.setValue(diagnose.getIcd10code());

        diagCreator.setText(Integer.toString(diagnose.getErsteller()));
        diagCreateTime.setText(diagnose.getErstellDatumZeit().toString());
        diagChanger.setText(Integer.toString(diagnose.getBearbeiter()));
        diagChangeTime.setText(diagnose.getBearbeitetDatumZeit().toString());
    }

    /**
     * Copy the data from the ComboBoxes into data model object
     *
     * @param diagnose The object to copy the data into
     */
    private void copyFieldDataIntoDiagnose(Diagnose diagnose) {
        diagnose.setIcd10code(diagDiagnose.getValue());
        diagnose.setArzt(diagDiagnoseArzt.getValue());
        diagnose.setFreiText(diagFreitext.getText());
        diagnose.setDiagArt(diagDiagnoseArt.getValue());
        diagnose.setFall(mainController.getFall());

        diagnose.setErsteller(mainController.getCurrentMitarbeiter().getMitarbID());
        diagnose.setBearbeiter(mainController.getCurrentMitarbeiter().getMitarbID());
    }

    /**
     * Clear the fields in case no diagnosis is selcted, or
     * creating a new one is started.
     */
    public void clearFields() {
        diagDiagnoseArzt.setValue(null);
        diagDiagnose.setValue(null);
        diagFreitext.setText("");
        diagDiagnoseArt.setValue(null);

        diagCreator.setText("");
        diagCreateTime.setText("");
        diagChanger.setText("");
        diagChangeTime.setText("");
    }

}