package au.id.zancanaro.javacheck.statem;

import java.util.Map;
import java.util.NoSuchElementException;

public abstract class CommandValue<T> {
    private final int id;

    public CommandValue(int id) {
        this.id = id;
    }

    public abstract boolean isAbstract();

    public abstract T get();

    public int getId() {
        return id;
    }

    static class AbstractValue<T> extends CommandValue<T> {
        public AbstractValue(int id) {
            super(id);
        }

        @Override
        public boolean isAbstract() {
            return true;
        }

        @Override
        public T get() {
            throw new NoSuchElementException("Abstract values cannot be supplied");
        }
    }

    static class ConcreteValue<T> extends CommandValue<T> {
        private final Map<Integer, Object> values;

        public ConcreteValue(int id, Map<Integer, Object> values) {
            super(id);
            this.values = values;
        }

        @Override
        public boolean isAbstract() {
            return true;
        }

        @Override
        @SuppressWarnings("unchecked")
        public T get() {
            if (values.containsKey(getId())) {
                return (T) values.get(getId());
            } else {
                throw new NoSuchElementException("Concrete values cannot be supplied prior to being calculated");
            }
        }
    }
}