package dark.web.frame.form;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import dark.web.frame.Form;
import dark.web.frame.Helper;
import dark.web.frame.Message;
import dark.web.frame.Value;

import org.apache.log4j.Logger;

/**
 * <p>Title:            表單驗證抽象類</p>
 * <p>Description:      定義表單驗證程序所必需的接口方法和公用方法</p>
 * <p>Copyright:        Copyright (c) 2004</p>
 * <p>Company:          DIS</p>
 * <p>Create Time:      2004-12-6 0:17:20</p>
 * @author             <a href="mailto:dark_he@hotmail.com">darkhe</a>
 * @version            1.0
 */
public abstract class AbstractForm implements Form
{
	protected static Logger log = Logger.getLogger("DWF");	
	
	private ServletContext servletContext;
	private HttpServletRequest request;
	private HttpServletResponse response;
	private Message message;

	private String input;

	/**
	 * 設(shè)置初始化參數(shù)，用于獲取servlet上下文、請求和反饋
	 * @param context
	 * @param request
	 * @param response
	 */
	public void init(
		ServletContext servletContext,
		HttpServletRequest request,
		HttpServletResponse response,
		Message message)
	{
		this.servletContext = servletContext;
		this.request = request;
		this.response = response;
		this.message = message;
	}

	/**
	 * @throws ServletException
	 * @throws IOException
	 */
	public void forward() throws ServletException, IOException
	{
		RequestDispatcher dispathcer =
			servletContext.getRequestDispatcher(input);
		dispathcer.forward(request, response);
	}

	/**
	 * 命令類的檢證方法，default返回true，開發(fā)人員可根據(jù)具
	 * 體商來邏輯來重置當前方法的行為。只要當前返回true的情
	 * 況下，validate方法才被執(zhí)行
	 * @return 
	 * @throws ServletException
	 * @throws IOException
	 */
	public boolean isAuthentic() throws ServletException, IOException
	{
		return true;
	}

	/**
	 * 表單驗證方法，子類必須實現(xiàn)當前方法已實現(xiàn)子類已經(jīng)的具體的驗證邏輯
	 * 開發(fā)人員應(yīng)當將提示消息放入Message類。validate()方法返回的Message
	 * 對象的消息不為空則表明表單沒有通過，此時控制器將會將請求轉(zhuǎn)發(fā)到input
	 * 參數(shù)所指定的頁面
	 * @throws ServletException
	 * @throws IOException
	 */
	public abstract Message validate() throws ServletException, IOException;

	/**
	 * @return
	 */
	public HttpServletRequest getRequest()
	
	{
		return request;
	}

	/**
	 * @return
	 */
	public HttpServletResponse getResponse()
	{
		return response;
	}

	/**
	 * @return
	 */
	public ServletContext getServletContext()
	{
		return servletContext;
	}

	/**
	 * 返回請求轉(zhuǎn)發(fā)路徑
	 * @return 
	 */
	public String getInput()
	{
		return input;
	}

	/**
	 * 設(shè)定請求轉(zhuǎn)發(fā)路徑
	 * @param string
	 */
	public void setInput(String string)
	{
		input = string;
	}

	/**
	 * @return
	 */
	public Message getMessage()
	{
		return message;
	}

	/**
	 * @param request
	 * @return
	 */
	public static Message loadMessage(HttpServletRequest request)
	{
		return Helper.loadMessage(request);
	}

	/**
	 * @param session
	 * @return
	 */
	public static Message loadMessage(HttpSession session)
	{
		return Helper.loadMessage(session);
	}

	/**
	 * @param request
	 * @return
	 */
	public static Value loadValue(HttpServletRequest request)
	{
		return Helper.loadValue(request);
	}

	/**
	 * @param session
	 * @return
	 */
	public static Value loadValue(HttpSession session)
	{
		return Helper.loadValue(session);
	}

	/**
	 * @param m
	 * @param request
	 */
	public static void saveMessage(Message m, HttpServletRequest request)
	{
		Helper.saveMessage(m, request);
	}

	/**
	 * @param m
	 * @param session
	 */
	public static void saveMessage(Message m, HttpSession session)
	{
		Helper.saveMessage(m, session);
	}

	/**
	 * @param v
	 * @param request
	 */
	public static void saveValue(Value v, HttpServletRequest request)
	{
		Helper.saveValue(v, request);
	}

	/**
	 * @param v
	 * @param session
	 */
	public static void saveValue(Value v, HttpSession session)
	{
		Helper.saveValue(v, session);
	}

}