package net.tomatentum.cutin.method;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.security.InvalidParameterException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import net.tomatentum.cutin.util.ReflectionUtil;

public abstract class ReflectedMethod<I extends Object, C extends Object> {

    private Logger logger = LoggerFactory.getLogger(getClass());

    protected Method method;
    protected Object containingObject;

    protected ReflectedMethod(Method method, Object containingObject) {
        if (!Arrays.asList(containingObject.getClass().getDeclaredMethods()).contains(method))
            throw new InvalidParameterException("Method does not apply to specified handler");
        this.method = method;
        this.containingObject = containingObject;
    }

    public abstract Object getParameter(C context, int index);

    public abstract I identifier();

    public Object run(C context) {
        method.setAccessible(true);
        try {
            return method.invoke(containingObject, getParameters(context));
        }catch (IllegalAccessException | InvocationTargetException ex) {
            logger.error("ReflectedMethod failed to run", ex);
            return null;
        }
    }

    public Method method() {
        return this.method;
    }

    public Object containingObject() {
        return this.containingObject;
    }

    @Override
    public String toString() {
        return identifier().toString();
    }

    private Object[] getParameters(C context) {
        int parameterCount = method.getParameterCount();
        List<Object> parameters = new ArrayList<>();
        
        for (int i = 0; i < parameterCount; i++) {
            Object parameter = getParameter(context, i);
            logger.trace("Found parameter {}={} for method {}", parameter != null ? parameter.getClass().toString() : " ", parameter, ReflectionUtil.getFullMethodName(method));
            parameters.add(parameter);   
        }
        return parameters.toArray();
    }
    
}