package org.nutz.mvc.adaptor;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;
import java.lang.reflect.Type;
import javax.servlet.ServletContext;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.nutz.ioc.Ioc;
import org.nutz.lang.Lang;
import org.nutz.log.Log;
import org.nutz.log.Logs;
import org.nutz.mvc.HttpAdaptor;
import org.nutz.mvc.Scope;
import org.nutz.mvc.adaptor.injector.AllAttrInjector;
import org.nutz.mvc.adaptor.injector.AppAttrInjector;
import org.nutz.mvc.adaptor.injector.ErrorInjector;
import org.nutz.mvc.adaptor.injector.IocInjector;
import org.nutz.mvc.adaptor.injector.IocObjInjector;
import org.nutz.mvc.adaptor.injector.RequestAttrInjector;
import org.nutz.mvc.adaptor.injector.RequestInjector;
import org.nutz.mvc.adaptor.injector.ResponseInjector;
import org.nutz.mvc.adaptor.injector.ServletContextInjector;
import org.nutz.mvc.adaptor.injector.SessionAttrInjector;
import org.nutz.mvc.adaptor.injector.SessionInjector;
import org.nutz.mvc.annotation.Attr;
import org.nutz.mvc.annotation.IocObj;
import org.nutz.mvc.annotation.Param;
/**
*
* @author zozoh(zozohtnt@gmail.com)
* @author wendal(wendal1985@gmail.com)
*/
public abstract class AbstractAdaptor implements HttpAdaptor {
private static final Log log = Logs.get();
protected ParamInjector[] injs;
protected Method method;
public void init(Method method) {
this.method = method;
Class<?>[] argTypes = method.getParameterTypes();
injs = new ParamInjector[argTypes.length];
Annotation[][] annss = method.getParameterAnnotations();
Type[] types = method.getGenericParameterTypes();
for (int i = 0; i < annss.length; i++) {
Annotation[] anns = annss[i];
Param param = null;
Attr attr = null;
IocObj iocObj = null;
// find @Param & @Attr & @IocObj in current annotations
for (int x = 0; x < anns.length; x++)
if (anns[x] instanceof Param) {
param = (Param) anns[x];
break;
} else if (anns[x] instanceof Attr) {
attr = (Attr) anns[x];
break;
} else if (anns[x] instanceof IocObj) {
iocObj = (IocObj) anns[x];
break;
}
// If has @Attr
if (null != attr) {
injs[i] = evalInjectorByAttrScope(attr);
continue;
}
// If has @IocObj
if (null != iocObj) {
injs[i] = new IocObjInjector(method.getParameterTypes()[i], iocObj.value());
continue;
}
// And eval as default suport types
injs[i] = evalInjectorByParamType(argTypes[i]);
if (null != injs[i])
continue;
// Eval by sub-classes
injs[i] = evalInjector(types[i], param);
// 子类也不能确定，如何适配这个参数，那么做一个标记，如果
// 这个参数被 ParamInjector 适配到，就会抛错。
// 这个设计是因为了 "路径参数"
if (null == injs[i])
injs[i] = new ErrorInjector(method, i);
}
}
private static ParamInjector evalInjectorByAttrScope(Attr attr) {
if (attr.scope() == Scope.APP)
return new AppAttrInjector(attr.value());
if (attr.scope() == Scope.SESSION)
return new SessionAttrInjector(attr.value());
if (attr.scope() == Scope.REQUEST)
return new RequestAttrInjector(attr.value());
return new AllAttrInjector(attr.value());
}
private static ParamInjector evalInjectorByParamType(Class<?> type) {
// Request
if (ServletRequest.class.isAssignableFrom(type)) {
return new RequestInjector();
}
// Response
else if (ServletResponse.class.isAssignableFrom(type)) {
return new ResponseInjector();
}
// Session
else if (HttpSession.class.isAssignableFrom(type)) {
return new SessionInjector();
}
// ServletContext
else if (ServletContext.class.isAssignableFrom(type)) {
return new ServletContextInjector();
}
// Ioc
else if (Ioc.class.isAssignableFrom(type)) {
return new IocInjector();
}
return null;
}
protected ParamInjector evalInjector(Type type, Param param) {
Class<?> clazz = Lang.getTypeClass(type);
if( clazz == null) {
if(log.isWarnEnabled())
log.warnf("!!Fail to get Type Class : type=%s , param=%s",type,param);
return null;
}
return evalInjector(clazz, param);
}
/**
* 子类应该覆盖这个方法或者evalInjector(Type,Param)方法.
*/
protected ParamInjector evalInjector(Class<?> type, Param param) {
return null;
}
public Object[] adapt( ServletContext sc,
HttpServletRequest req,
HttpServletResponse resp,
String[] pathArgs) {
Object[] args = new Object[injs.length];
int len = Math.min(args.length, null == pathArgs ? 0 : pathArgs.length);
int i = 0;//确保路径参数不会被覆盖
// Inject another params
for (; i < len; i++) {
args[i] = injs[i].get(sc, req, resp, null == pathArgs ? null : pathArgs[i]);
}
Class<?>[] argTypes = method.getParameterTypes();
Object obj = getReferObject(sc, req, resp, pathArgs);
for (; i < injs.length; i++) {
args[i] = injs[i].get(sc, req, resp, obj);
if(args[i] == null && argTypes[i].isPrimitive()) {
args[i] = Lang.getPrimitiveDefaultValue(argTypes[i]);
}
}
return args;
}
protected Object getReferObject(ServletContext sc,
HttpServletRequest req,
HttpServletResponse resp,
String[] pathArgs) {
return null;
}
}