/**
 * Copyright (c) 2010-2022 Contributors to the openHAB project
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0
 *
 * SPDX-License-Identifier: EPL-2.0
 */
package org.openhab.binding.surepetcare.internal.utils;

import java.lang.reflect.Type;
import java.time.LocalTime;
import java.time.format.DateTimeFormatter;

import org.eclipse.jdt.annotation.NonNullByDefault;
import org.eclipse.jdt.annotation.Nullable;

import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonParseException;
import com.google.gson.JsonPrimitive;
import com.google.gson.JsonSerializationContext;
import com.google.gson.JsonSerializer;

/**
 * GSON serialiser/deserialiser for converting {@link LocalTime} objects.
 *
 * @author Rene Scherer - Initial Contribution
 */
@NonNullByDefault
public class GsonLocalTimeTypeAdapter implements JsonSerializer<LocalTime>, JsonDeserializer<LocalTime> {

    private static final DateTimeFormatter TIME_FORMATTER = DateTimeFormatter.ofPattern("HH:mm");

    /**
     * Gson invokes this call-back method during serialization when it encounters a field of the
     * specified type.
     * <p>
     *
     * In the implementation of this call-back method, you should consider invoking
     * {@link JsonSerializationContext#serialize(Object, Type)} method to create JsonElements for any
     * non-trivial field of the {@code src} object. However, you should never invoke it on the
     * {@code src} object itself since that will cause an infinite loop (Gson will call your
     * call-back method again).
     *
     * @param src the object that needs to be converted to Json.
     * @param typeOfSrc the actual type (fully genericized version) of the source object.
     * @return a JsonElement corresponding to the specified object.
     */
    @Override
    public JsonElement serialize(LocalTime src, Type typeOfSrc, JsonSerializationContext context) {
        return new JsonPrimitive(TIME_FORMATTER.format(src));
    }

    /**
     * Gson invokes this call-back method during deserialization when it encounters a field of the
     * specified type.
     * <p>
     *
     * In the implementation of this call-back method, you should consider invoking
     * {@link JsonDeserializationContext#deserialize(JsonElement, Type)} method to create objects
     * for any non-trivial field of the returned object. However, you should never invoke it on the
     * the same type passing {@code json} since that will cause an infinite loop (Gson will call your
     * call-back method again).
     *
     * @param json The Json data being deserialized
     * @param typeOfT The type of the Object to deserialize to
     * @return a deserialized object of the specified type typeOfT which is a subclass of {@code T}
     * @throws JsonParseException if json is not in the expected format of {@code typeOfT}
     */
    @Override
    public @Nullable LocalTime deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
            throws JsonParseException {
        return TIME_FORMATTER.parse(json.getAsString(), LocalTime::from);
    }
}
