/**
date: 2013-11-25
author: Limind
 */
package com.zjht.util;

import java.io.IOException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.jsp.JspException;
import javax.servlet.jsp.JspWriter;
import javax.servlet.jsp.tagext.TagSupport;

import com.zjht.common.Page;

/**
 * doStartTag()和doEndTag()返回值处理: SKIP_BODY (0) ：跳过了开始和结束标签之间的代码。
 * EVAL_BODY_INCLUDE(1)：将body的内容输出到存在的输出流中 SKIP_PAGE(5)： 忽略剩下的页面。
 * EVAL_PAGE隐含(6)：继续执行下面的页
 * 
 * @author Limind
 * @date 2013-11-25下午5:35:42
 */
public class PageTag extends TagSupport {

	private String url;

	public String getUrl() {
		return this.url;
	}

	public void setUrl(String url) {
		this.url = url;
	}

	public int doEndTag() throws JspException {
		return EVAL_PAGE;
	}

	public int doStartTag() throws JspException {
		HttpServletRequest request = (HttpServletRequest) this.pageContext
				.getRequest();
		// 获取分页bean
		Page page = (Page) request.getAttribute("page");

		JspWriter out = this.pageContext.getOut();
		// 拼接分页信息
		StringBuilder s = new StringBuilder();
		// 设置分页样式
		s = PageCss.getStyle();
		s.append("<div class=pageCss>");
		s.append("共<span>" + ((page.getTotal() - 1) / page.getPageSize() + 1)
				+ "</span>页 &nbsp; ");

		// 设置当前页第一条记录索引
		String pageJspNumber = request.getParameter("pageJspNumber");
		if (pageJspNumber != null && !"".equals(pageJspNumber)) {
			page.getPageable()
					.setPageJspNumber(Integer.parseInt(pageJspNumber));
		}
		if (page.getTotal() > page.getPageSize()) {
			// 获取连接符pref
			String pref;
			if (this.url.indexOf("?") > -1) {
				pref = "&";
			} else {
				pref = "?";
			}
			this.doStart(s, page, pref);
			this.doBody(s, page, pref);
			this.doEnd(s, page, pref);
		} else {
			s.append("&nbsp;&nbsp;&nbsp;&nbsp;");
		}
		s.append("&nbsp;共<span>" + page.getTotal() + "</span>条记录");
		s.append("&nbsp;&nbsp;&nbsp;&nbsp;跳转到 <input style='background:#d9c5a4; border: 1px solid #be9b64;width:50px;'>页 ");
		s.append("<a href='javascript:;' style='background:#d9c5a4; border: 1px solid #a8792f;' onClick='jumpNext()'>GO</a>\n");
		s.append("</div>");
		try {
			out.println(s.toString());
		} catch (IOException e) {
			e.printStackTrace();
		}

		return SKIP_BODY;
	}

/** 
	  * //拼接"首页"和"<" 
	  * @param s 
	  * @param page 
	  * @param pref 
	  */
	public void doStart(StringBuilder s, Page page, String pref) {
		if (page.getPageJspNumber() > 0) {
			s.append("<a href='javascript:;' style='background:#d9c5a4; border: 1px solid #a8792f;'  onClick='shouye()'>首页</a>\n"
					+ "<a href='javascript:;' style='background:#d9c5a4; border: 1px solid #a8792f;'  onClick='shangyiye("
					+ page.getLastOffset() + ")'>上页</a>\n");
		} else {
			s.append("<a href='javascript:;' style='background:#d9c5a4; border: 1px solid #a8792f;' onClick='shouye()'>首页</a>\n");
		}
	}

	/**
	 * 拼接"尾页"和">"
	 * 
	 * @param s
	 * @param page
	 * @param pref
	 */
	public void doEnd(StringBuilder s, Page page, String pref) {
		if (page.getPageJspNumber() < page.getTotal() - page.getPageSize()) {
			s.append("<a href='javascript:;' style='background:#d9c5a4; border: 1px solid #a8792f;' onClick='xiayiye("
					+ page.getNextOffset()
					+ ")'>下页</a>\n"
					+ "<a href='javascript:;' style='background:#d9c5a4; border: 1px solid #a8792f;' onClick='weiye("
					+ page.lastPageOffset() + ")'>尾页</a>\n");
		} else {
			s.append("\n"
					+ "<a href='javascript:;' style='background:#be9b64; border: 1px solid #be9b64; color:#fff;' onClick='weiye("
					+ page.lastPageOffset() + ")'>尾页</a>\n");
		}
	}

	/**
	 * 数字连接
	 * 
	 * @param s
	 * @param page
	 * @param pref
	 */
	public void doBody(StringBuilder s, Page page, String pref) {
		// 显示半径
		int radius = page.getPageable().MAX_PAGE_INDEX / 2 * page.getPageSize();

		// 显示数字的连接从第几条开始
		int startOffset;
		if ((page.getPageJspNumber() < radius)
				|| (page.getTotalPages() <= page.getPageable().MAX_PAGE_INDEX)) {
			startOffset = 0;
		} else {
			if (page.getPageJspNumber() < page.getTotal() - radius) {
				startOffset = page.getPageJspNumber() - radius;
			} else {
				startOffset = (int) ((page.getTotal() / page.getPageSize() - page
						.getPageable().MAX_PAGE_INDEX) * page.getPageSize());
			}
		}
		for (int i = startOffset; (i < page.getTotal())
				&& (i < startOffset + page.getPageable().MAX_PAGE_INDEX
						* page.getPageSize());) {
			if (i == page.getPageJspNumber()) {
				s.append("<b style='background:#be9b64; border: 1px solid #be9b64;'>"
						+ (i / page.getPageSize() + 1) + "</b>\n");
			} else {
				s.append("<a href='javascript:;' style='background:#d9c5a4; border: 1px solid #a8792f;' onClick='page("
						+ i + ")'>" + (i / page.getPageSize() + 1) + "</a>\n");
			}
			i += page.getPageSize();
		}
	}

}