package com.hehenian.manager.springsecurity;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.web.FilterInvocation;
import org.springframework.security.web.access.intercept.FilterInvocationSecurityMetadataSource;
import org.springframework.util.AntPathMatcher;
import org.springframework.util.PathMatcher;

import com.hehenian.manager.modules.sys.service.AuthorityService;

/**
 * 最核心的地方，就是提供某个资源对应的权限定义，即getAttributes方法返回的结果。 此类在初始化时，应该取到所有资源及其对应角色的定义。
 * 
 */
public class CustomInvocationSecurityMetadataSourceService implements
		FilterInvocationSecurityMetadataSource {

	protected AuthorityService authorityService;

	private PathMatcher urlMatcher = new AntPathMatcher();

	

	public CustomInvocationSecurityMetadataSourceService() {
	}

	private void loadResourceDefine() {
		// 在Web服务器启动时，提取系统中的所有权限。
		authorityService.getResourceMap();
	}

	@Override
	public Collection<ConfigAttribute> getAllConfigAttributes() {

		return null;
	}

	// 根据URL，找到相关的权限配置。
	@Override
	public Collection<ConfigAttribute> getAttributes(Object object)
			throws IllegalArgumentException {

		// object 是一个URL，被用户请求的url。
		String url = ((FilterInvocation) object).getRequestUrl();
		
        int firstQuestionMarkIndex = url.indexOf("?");

        if (firstQuestionMarkIndex != -1) {
            url = url.substring(0, firstQuestionMarkIndex);
        }

        Map<String, Collection<ConfigAttribute>> resourceMap=authorityService.getResourceMap();
		Iterator<String> ite = resourceMap.keySet().iterator();

		while (ite.hasNext()) {
			String resURL = ite.next();
			
			if (urlMatcher.matchStart(url, resURL)) {
				return resourceMap.get(resURL);
			}
		}
		return null;
	}

	@Override
	public boolean supports(Class<?> arg0) {

		return true;
	}


	@Autowired
	public void setAuthorityService(AuthorityService authorityService) {
		this.authorityService = authorityService;
		loadResourceDefine();
	}
}