AccentModifier.java

package org.geogebra.keyboard.base.model.impl;

import org.geogebra.keyboard.base.Accents;
import org.geogebra.keyboard.base.Action;
import org.geogebra.keyboard.base.ActionType;
import org.geogebra.keyboard.base.Background;
import org.geogebra.keyboard.base.ResourceType;
import org.geogebra.keyboard.base.model.KeyModifier;

public class AccentModifier implements KeyModifier {

    private static final byte GRAVE_ACCENT = 0b0001;
    private static final byte CIRCUMFLEX_ACCENT = 0b0010;
    private static final byte CARON_ACCENT = 0b0100;
    private static final byte ACUTE_ACCENT = 0b1000;

    private int currentAccent = 0;

    private Accents accents = new Accents();

    public boolean toggleAccent(String accent) {
        boolean changed = true;
        if (accent != null) {
            switch (accent) {
                case Accents.ACCENT_ACUTE:
                    currentAccent = ~currentAccent & ACUTE_ACCENT;
                    break;
                case Accents.ACCENT_CARON:
                    currentAccent = ~currentAccent & CARON_ACCENT;
                    break;
                case Accents.ACCENT_CIRCUMFLEX:
                    currentAccent = ~currentAccent & CIRCUMFLEX_ACCENT;
                    break;
                case Accents.ACCENT_GRAVE:
                    currentAccent = ~currentAccent & GRAVE_ACCENT;
                    break;
                default:
                    changed = false;
            }
        } else {
            changed = currentAccent != (currentAccent = 0);
        }
        return changed;
    }

    @Override
    public String modifyResourceName(String resourceName, ResourceType resourceType) {
        if (resourceType == ResourceType.TEXT && resourceName.length() == 1) {
            return getAccent(resourceName);
        }
        return resourceName;
    }

    @Override
    public String modifyActionName(String actionName, ActionType actionType) {
        if (actionType == ActionType.INPUT && actionName.length() == 1) {
            return getAccent(actionName);
        }
        return actionName;
    }

    @Override
    public Background modifyBackground(Background background, ActionType actionType, String actionName) {
        if (actionType == ActionType.CUSTOM && (
                (actionName.equals(Action.TOGGLE_ACCENT_ACUTE.name()) && hasAccent(ACUTE_ACCENT)) ||
                (actionName.equals(Action.TOGGLE_ACCENT_CARON.name()) && hasAccent(CARON_ACCENT)) ||
                (actionName.equals(Action.TOGGLE_ACCENT_GRAVE.name()) && hasAccent(GRAVE_ACCENT)) ||
                (actionName.equals(Action.TOGGLE_ACCENT_CIRCUMFLEX.name()) && hasAccent(CIRCUMFLEX_ACCENT)))) {
            return Background.STANDARD_PRESSED;
        }
        return background;
    }

    private String getAccent(String letter) {
        String returnValue = null;
        if (hasAccent(GRAVE_ACCENT)) {
            returnValue = accents.getGraveAccent(letter);
        } else if (hasAccent(ACUTE_ACCENT)) {
            returnValue = accents.getAcuteLetter(letter);
        } else if (hasAccent(CARON_ACCENT)) {
            returnValue = accents.getCaronLetter(letter);
        } else if (hasAccent(CIRCUMFLEX_ACCENT)) {
            returnValue = accents.getCircumflexLetter(letter);
        }
        return returnValue != null ? returnValue : letter;
    }

    private boolean hasAccent(byte accent) {
        return (currentAccent & accent) != 0;
    }
}