Gamelib/src/main/java/uulm/teamname/marvelous/gamelibrary/json/JSON.java

package uulm.teamname.marvelous.gamelibrary.json;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.InjectableValues;
import com.fasterxml.jackson.databind.ObjectMapper;
import uulm.teamname.marvelous.gamelibrary.config.CharacterConfig;
import uulm.teamname.marvelous.gamelibrary.messages.BasicMessage;
import uulm.teamname.marvelous.gamelibrary.messages.server.EventMessage;

import java.util.Optional;

/**
 * Class that contains JSON encoding and decoding. It is initiated with the Character configuration.
 */
public class JSON {

    private final ObjectMapper mapper = new ObjectMapper();

    public JSON (CharacterConfig config) {
        // add the config to the mappers InjectableValues, where it is later accessed by the EntityDeserializer
        this.mapper.setInjectableValues(new InjectableValues
                .Std()
                .addValue("CharacterConfig", config));
    }

    /** Deserializes an incoming network message into a {@link EventMessage}.
     * @param input The JSON to deserialize
     * @return An {@link Optional} containing the parsed message (as {@link BasicMessage}, so typecasting is necessary)
     *         or an empty {@link Optional} if the deserialization failed
     */
    public Optional<BasicMessage> parse(String input) {
        try {
            return Optional.of(mapper.readValue(input, BasicMessage.class));
        } catch (JsonProcessingException e) {
            e.printStackTrace();
            return Optional.empty();
        }
    }

    /** Serializes a {@link EventMessage} into a JSON string.
     * @param input The message to serialize
     * @return An {@link Optional}<{@link String}> of the message as JSON or
     *         an empty {@link Optional} if the serialization failed
     */
    public Optional<String> stringify(BasicMessage input) {
        try {
            return Optional.of(mapper.writeValueAsString(input));
        } catch (JsonProcessingException e) {
            e.printStackTrace();
            return Optional.empty();
        }
    }
}