/**
 * Copyright (C) 2021 Adrien Hopkins
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
package sevenUnits.newGUI;

import java.util.List;
import java.util.Optional;
import java.util.OptionalDouble;

import sevenUnits.unit.BaseDimension;
import sevenUnits.unit.Unit;
import sevenUnits.unit.UnitValue;
import sevenUnits.utils.NamedObjectProduct;
import sevenUnits.utils.ObjectProduct;

/**
 * A View that supports single unit-based conversion
 * 
 * @author Adrien Hopkins
 * @since 2021-12-15
 */
public interface UnitConversionView extends View {
	/**
	 * @return unit to convert <em>from</em>
	 * @since 2021-12-15
	 */
	Optional<Unit> getFromSelection();
	
	/**
	 * @return value to convert between the units
	 * @since 2021-12-15
	 */
	OptionalDouble getInputValue();
	
	/**
	 * @return selected dimension
	 * @since 2021-12-15
	 */
	Optional<ObjectProduct<BaseDimension>> getSelectedDimension();
	
	/**
	 * @return unit to convert <em>to</em>
	 * @since 2021-12-15
	 */
	Optional<Unit> getToSelection();
	
	/**
	 * Sets the available dimensions for filtering.
	 *
	 * @param dimensions dimensions to use
	 * @since 2021-12-15
	 */
	void setDimensions(List<NamedObjectProduct<BaseDimension>> dimensions);
	
	/**
	 * Sets the available units to convert from. {@link #getFromSelection} is not
	 * required to use one of these units; this method is to be used for views
	 * that allow the user to select units from a list.
	 *
	 * @param units units to convert from
	 * @since 2021-12-15
	 */
	void setFromUnits(List<? extends Unit> units);
	
	/**
	 * Sets the available units to convert to. {@link #getToSelection} is not
	 * required to use one of these units; this method is to be used for views
	 * that allow the user to select units from a list.
	 *
	 * @param units units to convert to
	 * @since 2021-12-15
	 */
	void setToUnits(List<? extends Unit> units);
	
	/**
	 * Shows the output of a unit conversion.
	 * 
	 * @param input  unit value before conversion, as obtained from the view
	 * @param output unit value after conversion
	 * @throws NullPointerException if either argument is null
	 * @since 2021-12-15
	 */
	void showUnitConversionOutput(UnitValue input, UnitValue output);
}