package foundation.action;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

import foundation.dao.DataReader;
import foundation.dao.DataWriter;
import foundation.dao.bizlogic.IActionProvider;
import foundation.handler.DataPool;
import foundation.handler.ResultPool;
import foundation.handler.SingletonHandler;
import foundation.route.Operation;

public abstract class SingletonActionProvider extends SingletonHandler implements IActionProvider {

	@Override
	public void exec(ActionContext context, String methodName) throws Exception {
		Method method = getMethod(methodName);
		
		if (method == null) {
			logger.error("method exec error: {} not exists", methodName);
			return;
		}
		
		try {
			method.invoke(this, context);
		}
		catch (InvocationTargetException e) {
			e.printStackTrace();
			Throwable throwable = e.getTargetException();

			if (throwable == null) {
				throw e;
			}
			else {
				throw (Exception) throwable;
			}
		}		
	}
	
	public void test(ActionContext context, String methodName) throws Exception {
		logger.info("action provider {}.{} test", context.getActionName(), methodName);
	}

	@Override
	protected void invokeMethod(Method method, DataPool dataPool, ResultPool resultPool) throws Exception {
		//1. 
		Operation operation = dataPool.getOperation();
		DataReader dataReader = new DataReader(operation, dataPool);
		
		DataWriter dataWriter = new DataWriter(resultPool, dataReader.getDomain());
		resultPool.setLetterWriter(dataWriter);
		
		String dataName = dataReader.getDomain().getDataName();
		WorkStep step = new WorkStep(dataName, operation.getOperator());
		ActionContext context = new ActionContext(dataReader, dataWriter, step);
		
		//2. 
		try {
			method.invoke(this, context);
		}
		catch (InvocationTargetException e) {
			e.printStackTrace();
			Throwable throwable = e.getTargetException();

			if (throwable == null) {
				throw e;
			}
			else {
				throw (Exception) throwable;
			}
		}		
	}

	public void terminateTask(ActionContext context) {
		IWorkflowRuntime task = context.getWorkFlow();
		
		if (task != null) {
			task.terminate();
		}
	}
	
	@Override
	protected boolean validateMethodParameter(Class<?>[] parameters) {
		if (parameters == null || parameters.length != 1) {
			return false;
		}
		
		Class<?> type = parameters[0];
		return type.isAssignableFrom(ActionContext.class);
	}
}