/**
 * @(#)LocalDateCombo.java	1.0 2015/02/19
 */
package darrylbu.component;

import java.awt.Component;
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
import java.time.format.FormatStyle;
import java.time.temporal.TemporalAccessor;
import javax.swing.DefaultComboBoxModel;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JComboBox;
import javax.swing.JList;
import javax.swing.JPopupMenu;
import javax.swing.SwingUtilities;
import javax.swing.event.PopupMenuEvent;
import javax.swing.event.PopupMenuListener;

/**
 * LocalDateCombo is a Swing date picker for selecting a java.time.LocalDate from a drop-down
 * {@link MonthView}.
 * <P>
 * <B>Note that compiling or using this class requires Java 8</B>
 *
 * @author Darryl
 * @see LocalDate
 */
public class LocalDateCombo extends JComboBox<LocalDate> {

  private final DefaultComboBoxModel<LocalDate> comboModel = new DefaultComboBoxModel<>();
  private LocalDate min;
  private LocalDate max;
  private final MonthView monthView;
  private final JPopupMenu popupMenu = new JPopupMenu();

  /**
   * Constructs a LocalDateCombo with today's date, no upper or lower limits, formatted in a medium
   * style.
   *
   * @see FormatStyle#MEDIUM
   */
  public LocalDateCombo() {
    this(DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM));
  }

  /**
   * Constructs a LocalDateCombo with today's date and no upper or lower limits, formatted according
   * to the provided formatter.
   *
   * @param formatter Formats the date for display
   *
   * @see DateTimeFormatter
   */
  public LocalDateCombo(DateTimeFormatter formatter) {
    this(LocalDate.now(), formatter);
  }

  /**
   * Constructs a LocalDateCombo with the date provided and no lower or upper limits, formatted in a
   * medium style.
   *
   * @param value The initial value
   *
   * @see FormatStyle#MEDIUM
   */
  public LocalDateCombo(LocalDate value) {
    this(value, DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM));
  }

  /**
   * Constructs a LocalDateCombo with the date provided and no lower or upper limits, formatted
   * according to the provided formatter.
   *
   * @param value The initial value
   * @param formatter Formats the date for display
   */
  public LocalDateCombo(LocalDate value, DateTimeFormatter formatter) {
    this(value, null, null, formatter);
  }

  /**
   * Constructs a LocalDateCombo with the date, lower (earliest) and upper (latest) limits provided,
   * formatted in a medium style.
   * <P>
   * Dates outside the specified range are not displayed.
   * <P>
   * This class does not attempt to verify that minDate <= value <= maxDate. It is the
   * responsibility of client code to supply sane values.
   *
   * @param value The initial value
   * @param minDate The minimum value (earliest date); <CODE>null</CODE> for no limit.
   * @param maxDate The maximum value (latest date); <CODE>null</CODE> for no limit.
   *
   * @see FormatStyle#MEDIUM
   */
  public LocalDateCombo(LocalDate value, LocalDate minDate, LocalDate maxDate) {
    this(value, minDate, maxDate, DateTimeFormatter.ofLocalizedDate(FormatStyle.MEDIUM));
  }

  /**
   * Constructs a LocalDateCombo with the date, lower (earliest) and upper (latest) limits provided,
   * formatted according to the provided formatter.
   * <P>
   * Dates outside the specified range are not displayed.
   * <P>
   * This class does not attempt to verify that minDate <= value <= maxDate. It is the
   * responsibility of client code to supply sane values.
   *
   * @param value The initial value
   * @param minDate The minimum value (earliest date); <CODE>null</CODE> for no limit.
   * @param maxDate The maximum value (latest date); <CODE>null</CODE> for no limit.
   * @param formatter Formats the date for display
   */
  public LocalDateCombo(LocalDate value, LocalDate minDate, LocalDate maxDate,
      DateTimeFormatter formatter) {
    // Thursday after 24 of September
    LocalDate longNameDate = LocalDate.now().withDayOfMonth(24).withMonth(9);
    longNameDate = longNameDate.plusDays(4 - longNameDate.getDayOfWeek().getValue());
    setPrototypeDisplayValue(longNameDate);

    monthView = new MonthView(value, minDate, maxDate);
    comboModel.addElement(value);
    setModel(comboModel);
    setRenderer(new DefaultListCellRenderer() {
      @Override
      public Component getListCellRendererComponent(JList<?> list, Object value,
          int index, boolean isSelected, boolean hasFocus) {
        super.getListCellRendererComponent(list, value, index, isSelected, hasFocus);
        setText(formatter.format((TemporalAccessor) value));
        return this;
      }
    });

    min = minDate;
    max = maxDate;
    popupMenu.add(monthView);

    addPopupMenuListener(new PopupMenuListener() {

      @Override
      public void popupMenuWillBecomeVisible(PopupMenuEvent pme) {
        final boolean popupShown = popupMenu.isShowing();
        SwingUtilities.invokeLater(() -> {
          hidePopup();
          if (popupShown) {
            popupMenu.setVisible(false);
          } else {
            monthView.setValue(getValue());
            popupMenu.show(LocalDateCombo.this, 0, getHeight());
          }
        });
      }

      @Override
      public void popupMenuWillBecomeInvisible(PopupMenuEvent pme) {
      }

      @Override
      public void popupMenuCanceled(PopupMenuEvent pme) {
      }
    });

    monthView.addPropertyChangeListener("Confirm", pce -> {
      popupMenu.setVisible(false);
    });
    monthView.addPropertyChangeListener("Value", pce -> {
      setValue((LocalDate) pce.getNewValue());
      firePropertyChange("Value", pce.getOldValue(), pce.getNewValue());
    });
  }

  /**
   * Returns the current value
   *
   * @return the current value
   */
  public LocalDate getValue() {
    return comboModel.getElementAt(0);//value;
  }

  /**
   * Sets the current value, adjusted to be within any specified min/max range.
   *
   * @param value The value to set
   */
  public void setValue(LocalDate value) {
    if (getSelectedItem().equals(value)) {
      return;
    }
    if (min != null && value.isBefore(min)) {
      value = min;
    }
    if (max != null && value.isAfter(max)) {
      value = max;
    }
    comboModel.removeAllElements();
    comboModel.addElement(value);
    if (!monthView.getValue().equals(value)) {
      monthView.setValue(value);
    }
  }

  /**
   * Returns the minimum value (earliest date), or <CODE>null</CODE> if no limit is set.
   *
   * @return The earliest date that can be selected.
   */
  public LocalDate getMin() {
    return min;
  }

  /**
   * Sets the minimum value (earliest date). Call this method with a <CODE>null</CODE> value for no
   * limit.
   * <P>
   * This class does not attempt to verify that min <= value <= max. It is the responsibility of
   * client code to supply a sane value.
   *
   * @param min The earliest date that can be selected, or <CODE>null</CODE> for no limit.
   */
  public void setMin(LocalDate min) {
    this.min = min;
    monthView.setMin(min);
  }

  /**
   * Returns the maximum value (latest date), or <CODE>null</CODE> if no limit is set.
   *
   * @return The latest date that can be selected.
   */
  public LocalDate getMax() {
    return max;
  }

  /**
   * Sets the maximum value (latest date). Call this method with a <CODE>null</CODE> value for no
   * limit.
   * <P>
   * This class does not attempt to verify that min <= value <= max. It is the responsibility of
   * client code to supply a sane value.
   *
   * @param max The latest date that can be selected, or <CODE>null</CODE> for no limit.
   */
  public void setMax(LocalDate max) {
    this.max = max;
    monthView.setMax(max);
  }
}