package com.common.security.configure;

import com.common.annotation.NoAuthorize;
import com.common.annotation.NoToken;
import com.common.core.utils.SpringContextUtils;
import org.aopalliance.intercept.MethodInvocation;
import org.springframework.security.access.AccessDecisionVoter;
import org.springframework.security.access.ConfigAttribute;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.GrantedAuthority;
import org.springframework.security.web.FilterInvocation;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.mvc.condition.PatternsRequestCondition;
import org.springframework.web.servlet.mvc.method.RequestMappingInfo;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;

import javax.servlet.http.HttpServletRequest;
import java.util.*;
import java.util.stream.Collectors;


public class RoleBasedVoter implements AccessDecisionVoter<Object> {

    @Override
    public boolean supports(ConfigAttribute attribute) {
        return true;
    }

    @Override
    public int vote(Authentication authentication, Object object, Collection<ConfigAttribute> attributes) {
        FilterInvocation fi = (FilterInvocation) object;
        HttpServletRequest fiRequest = fi.getRequest();
        String requestURI = fiRequest.getRequestURI();
        Map<RequestMappingInfo, HandlerMethod> handlerMethods = ((RequestMappingHandlerMapping)SpringContextUtils.getBean("requestMappingHandlerMapping")).getHandlerMethods();
        Set<String> anonymousUrls = new HashSet<>();
        for (Map.Entry<RequestMappingInfo, HandlerMethod> infoEntry : handlerMethods.entrySet()) {
            // 获取所有接口的方法
            HandlerMethod handlerMethod = infoEntry.getValue();
            if ( handlerMethod.hasMethodAnnotation(NoAuthorize.class)) {
                PatternsRequestCondition requestCondition = infoEntry.getKey().getPatternsCondition();
                Optional.ofNullable(requestCondition).orElseThrow(RuntimeException::new);
                anonymousUrls.addAll(requestCondition.getPatterns().stream().map(m -> SpringContextUtils.getEnvParam("server.servlet.context-path")+m).collect(Collectors.toList()));
            }
            if ( handlerMethod.hasMethodAnnotation(NoToken.class)) {
                PatternsRequestCondition requestCondition = infoEntry.getKey().getPatternsCondition();
                Optional.ofNullable(requestCondition).orElseThrow(RuntimeException::new);
                anonymousUrls.addAll(requestCondition.getPatterns().stream().map(m -> SpringContextUtils.getEnvParam("server.servlet.context-path")+m).collect(Collectors.toList()));
            }
        }

        for(String item : Arrays.asList(new String[]{
                ".html",
                ".css",
                ".js",
                ".png",
                ".ttf",
                ".ico",
                ".woff",
                "/swagger-resources",
                "/v2/api-docs",
                "/druid"
        })){
            if(requestURI.contains(item)){
                return ACCESS_GRANTED;
            }
        }

        if(anonymousUrls.contains(requestURI)){
            return ACCESS_GRANTED;
        }
        if(authentication == null) {
            return ACCESS_DENIED;
        }
        int result = ACCESS_ABSTAIN;
        Collection<? extends GrantedAuthority> authorities = extractAuthorities(authentication);
        for (ConfigAttribute attribute : attributes) {
            if (this.supports(attribute)) {
                //TODO 目前是所有请求都要判断权限，如后续有不需要判断的，可以启动时从数据库加载到缓存
                result = ACCESS_DENIED;
                // Attempt to find a matching granted authority
                for (GrantedAuthority authority : authorities) {
                    if (requestURI.equals(authority.getAuthority())) {
                        return ACCESS_GRANTED;
                    }
                }
            }
        }
        return result;
    }

    Collection<? extends GrantedAuthority> extractAuthorities(
        Authentication authentication) {
        return authentication.getAuthorities();
    }

    @Override
    public boolean supports(Class clazz) {
        return true;
    }
}