/**

 * Created by Irving on 2014/11/24.

 * OAuth2 客户端实现

 */

@Controller

@RequestMapping("/client")

public class ClientController {

    private static Logger logger = LoggerFactory.getLogger(ClientController.class);

    /*

        response_type：表示授权类型，必选项，此处的值固定为"code"

        client_id：表示客户端的ID，必选项

        redirect_uri：表示重定向URI，可选项

        scope：表示申请的权限范围，可选项

        state：表示客户端的当前状态，可以指定任意值，认证服务器会原封不动地返回这个值

    */

    /**

     * 获得授权码

     * @return

     */

    @RequestMapping(method = RequestMethod.GET)

    public String client() {

        try {

            OAuthClientRequest oauthResponse = OAuthClientRequest

                                               .authorizationLocation(ConstantKey.OAUTH_CLIENT_AUTHORIZE)

                                               .setResponseType(OAuth.OAUTH_CODE)

                                               .setClientId(ConstantKey.OAUTH_CLIENT_ID)

                                               .setRedirectURI(ConstantKey.OAUTH_CLIENT_CALLBACK)

                                               .setScope(ConstantKey.OAUTH_CLIENT_SCOPE)

                                               .buildQueryMessage();

            return "redirect:"+oauthResponse.getLocationUri();

        } catch (OAuthSystemException e) {

            e.printStackTrace();

        }

        return "redirect:/home";

    }

    /*

        grant_type：表示使用的授权模式，必选项，此处的值固定为"authorization_code"

        code：表示上一步获得的授权码，必选项。

        redirect_uri：表示重定向URI，必选项，且必须与A步骤中的该参数值保持一致

        client_id：表示客户端ID，必选项

    */

    /**

     * 获得令牌

     * @return oauth_callback?code=1234

     */

    @RequestMapping(value = "/oauth_callback" ,method = RequestMethod.GET)

    public String getToken(HttpServletRequest request,Model model) throws OAuthProblemException {

        OAuthAuthzResponse oauthAuthzResponse = null;

        try {

            oauthAuthzResponse = OAuthAuthzResponse.oauthCodeAuthzResponse(request);

            String code = oauthAuthzResponse.getCode();

            OAuthClientRequest oauthClientRequest = OAuthClientRequest

                                                    .tokenLocation(ConstantKey.OAUTH_CLIENT_ACCESS_TOKEN)

                                                    .setGrantType(GrantType.AUTHORIZATION_CODE)

                                                    .setClientId(ConstantKey.OAUTH_CLIENT_ID)

                                                    .setClientSecret(ConstantKey.OAUTH_CLIENT_SECRET)

                                                    .setRedirectURI(ConstantKey.OAUTH_CLIENT_CALLBACK)

                                                    .setCode(code)

                                                    .buildQueryMessage();

            OAuthClient oAuthClient = new OAuthClient(new URLConnectionClient());

            //Facebook is not fully compatible with OAuth 2.0 draft 10, access token response is

            //application/x-www-form-urlencoded, not json encoded so we use dedicated response class for that

            //Custom response classes are an easy way to deal with oauth providers that introduce modifications to

            //OAuth 2.0 specification

            //获取access token

            OAuthJSONAccessTokenResponse oAuthResponse = oAuthClient.accessToken(oauthClientRequest, OAuth.HttpMethod.POST);

            String accessToken = oAuthResponse.getAccessToken();

            String refreshToken= oAuthResponse.getRefreshToken();

            Long expiresIn = oAuthResponse.getExpiresIn();

            //获得资源服务

            OAuthClientRequest bearerClientRequest = new OAuthBearerClientRequest(ConstantKey.OAUTH_CLIENT_GET_RESOURCE)

                                                     .setAccessToken(accessToken).buildQueryMessage();

            OAuthResourceResponse resourceResponse = oAuthClient.resource(bearerClientRequest, OAuth.HttpMethod.GET, OAuthResourceResponse.class);

            String resBody = resourceResponse.getBody();

            logger.info("accessToken: "+accessToken +" refreshToken: "+refreshToken +" expiresIn: "+expiresIn +" resBody: "+resBody);

            model.addAttribute("accessToken",  "accessToken: "+accessToken + " resBody: "+resBody);

            return "oauth2/token";

        } catch (OAuthSystemException ex) {

            logger.error("getToken OAuthSystemException : " + ex.getMessage());

            model.addAttribute("errorMsg",  ex.getMessage());

            return  "/oauth2/error";

        }

    }

}