package foundation.route;

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

import foundation.handler.Handler;
import foundation.handler.IHandler;
import foundation.handler.SingletonHandler;
import foundation.util.Util;

public class VirtualPath {

	private RouteType type;
	private String path;
	private String resourceTarget;
	private Class<? extends Handler> instanceObjectClass;
	private Class<? extends SingletonHandler> singletonObjectClass;
	private Method getSingletonInstanceMethod;
	private String[] resourceSegments;
	private String[] pathSegments;
	

	public VirtualPath(String path, String target, String className) throws Exception {
		this.path = path;
		
		if (!Util.isEmpty(className)) {
			this.type = RouteType.Controller;
			this.resourceTarget = target;
			setCallableClassName(className);
		}
		else {
			this.type = RouteType.Resource;
			this.resourceTarget = target.startsWith("/") ? target : "root/"  + target;
		}
		
		resourceSegments = resourceTarget == null ? new String[0] : resourceTarget.split("/");
		pathSegments = path == null ? new String[0] : path.split("/");
	}

	public IHandler getHttpObject() throws InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
		if (instanceObjectClass != null) {
			return instanceObjectClass.newInstance();
		}
		
		if (singletonObjectClass != null) {
			return (IHandler) getSingletonInstanceMethod.invoke(null);
		}
		
		return null;
	}

	@SuppressWarnings({ "rawtypes", "unchecked" })
	public void setCallableClassName(String classname) throws Exception {
		//1.
		Class clazz = Class.forName(classname);
		
		if (Handler.class.isAssignableFrom(clazz)) {
			//1.1. 如果是可以多实例化的HttpObject
			instanceObjectClass = (Class<? extends Handler>) clazz;
		}
		else if (SingletonHandler.class.isAssignableFrom(clazz)) {
			//1.2. 如果是只能单例的HttpObject
			singletonObjectClass = (Class<? extends SingletonHandler>) clazz;
			getSingletonInstanceMethod = clazz.getDeclaredMethod("getInstance");
		}
		else {
			throw new Exception("error callable class: " + clazz);
		}
	}

	public RouteType getType() {
		return type;
	}

	public String getResourceTarget() {
		return resourceTarget;
	}

	@Override
	public String toString() {
		if (instanceObjectClass != null) {
			return instanceObjectClass.getName();
		}
		
		if (singletonObjectClass != null) {
			return singletonObjectClass.getName();
		}
		
		return resourceTarget;
	}
	
	public String getPath() {
		return path;
	}

	public String[] getResourceSegments() {
		return resourceSegments;
	}

	public String[] getPathSegments() {
		return pathSegments;
	}

}