package util;

import io.netty.handler.codec.http.HttpMethod;

public class Constants {
	public enum OAUTH2_CLIENT {
		NAVER(
			/* auth uri     */ "https://nid.naver.com/oauth2.0/authorize"
			/* auth method  */, HttpMethod.POST
			/* token uri    */, "https://nid.naver.com/oauth2.0/token"
			/* token method */, HttpMethod.POST
			/* resource uri           */, "https://openapi.naver.com/v1/nid/me"
			/* resource method        */, HttpMethod.POST
			/* resource header keys   */, new String[] {"Authorization"}
			/* resource header values */, new String[] {"Bearer "}
			/* client id     */, "MY_CLIENT_ID"
			/* client secret */, "MY_CLIENT_SECRET"
			/* callback uri  */, "MY_CALLBACK_URL"
		),
		;
		private String authUri;
		private HttpMethod authPreferedMethod;
		private String tokenUri;
		private HttpMethod tokenPreferedMethod;
		private String resourceServerUrl;
		private HttpMethod resourceServerPreferedMethod;
		private String[] resourceHeaderKey;
		private String[] resourceHeaderValue;
		private String clientId;
		private String clientSecret;
		private String callbackUri;
		public String getAuthUri() { return this.authUri; }
		public HttpMethod getAuthPreferedMethod() { return this.authPreferedMethod; }
		public String getTokenUri() { return this.tokenUri; }
		public HttpMethod getTokenPreferedMethod() { return this.tokenPreferedMethod; }
		public String getResourceServerUrl() { return this.resourceServerUrl; }
		public HttpMethod getResourceServerPreferedMethod() { return this.resourceServerPreferedMethod; }
		public String[] getResourceHeaderKeys() { return this.resourceHeaderKey; }
		public String[] getResourceHeaderValues() { return this.resourceHeaderValue; }
		public String getClientId() {return this.clientId; }
		public String getClientSecret() { return this.clientSecret; }
		public String getCallbackUri() { return this.callbackUri; }
		@Override
		public String toString() { return "DO NOT USE DEFAULT TOSTRING"; }
		private OAUTH2_CLIENT(
				String authUri
				, HttpMethod authPreferedMethod
				, String tokenUri
				, HttpMethod tokenPreferedMethod
				, String resourceServerUrl
				, HttpMethod resourceServerPreferedMethod
				, String[] resourceHeaderKey
				, String[] resourceHeaderValue
				, String clientId
				, String clientSecret
				, String callbackUri
		) {
			this.authUri = authUri;
			this.authPreferedMethod = authPreferedMethod;

			this.tokenUri = tokenUri;
			this.tokenPreferedMethod = tokenPreferedMethod;

			this.resourceServerUrl = resourceServerUrl;
			this.resourceServerPreferedMethod = resourceServerPreferedMethod;
			this.resourceHeaderKey = resourceHeaderKey;
			this.resourceHeaderValue = resourceHeaderValue;

			this.clientId = clientId;
			this.clientSecret = clientSecret;
			this.callbackUri = callbackUri;
		}
	}//END OF ENUM
}//END OF CLASS

package controller;

import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.net.URLEncoder;
import java.nio.charset.Charset;
import java.security.SecureRandom;
import java.util.Map;

import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

import com.fasterxml.jackson.databind.ObjectMapper;

import util.Constants.OAUTH2_CLIENT;
import util.HttpUtils;

@Controller
public class TestAuthFacebookController {

	private static final Logger logger = LoggerFactory.getLogger(TestAuthFacebookController.class);
	public static String storedState = "";

	@RequestMapping(value="oauth/facebook/init", method=RequestMethod.GET)
	public ModelAndView oAuth2TestFacebookInit(HttpServletResponse httpServletResponse) throws UnsupportedEncodingException {
	    String stateToken = new BigInteger(130, new SecureRandom()).toString(32);
	    logger.debug("stateToken : " + stateToken);
	    TestAuthFacebookController.storedState = stateToken;
	    String redirectUrl = OAUTH2_CLIENT.FACEBOOK.getAuthUri()
	    		+ "?client_id=" + OAUTH2_CLIENT.FACEBOOK.getClientId()
	    		+ "&response_type=code"
	    		+ "&redirect_uri=" + URLEncoder.encode(OAUTH2_CLIENT.FACEBOOK.getCallbackUri(), Charset.forName("UTF-8").toString())
	    		+ "&state=" + stateToken
	    		+ "&scope=public_profile email manage_pages";
	    return new ModelAndView("redirect:" + redirectUrl);
	}//END OF FUNCTION

	@RequestMapping(value="oauth/facebook/callback", method=RequestMethod.GET)
	public String oAuth2TestFacebookCallback(@RequestParam Map<String,Object> map) throws Exception {
		String recvState = (String) map.get("state");
		logger.debug("recv state : " + recvState);
		String recvCode = (String) map.get("code");
		logger.debug("oAuth2TestFacebookCallback recv code : " + recvCode);
		if(TestAuthFacebookController.storedState.equals(recvState)) {
			String paramStr = ""
				+ "client_id=" + OAUTH2_CLIENT.FACEBOOK.getClientId()
				+ "&client_secret=" + OAUTH2_CLIENT.FACEBOOK.getClientSecret()
				+ "&code=" + recvCode
				+ "&redirect_uri=" + OAUTH2_CLIENT.FACEBOOK.getCallbackUri();

			ObjectMapper mapper = new ObjectMapper();
			String jsonInString = HttpUtils.sendAndRecv(
				OAUTH2_CLIENT.FACEBOOK.getTokenUri()
				, OAUTH2_CLIENT.FACEBOOK.getTokenPreferedMethod()
				, paramStr
			);

			logger.debug("AuthorizationServer recv : " + jsonInString);

		} else {
			throw new Exception("");
			//401 unauthorized
		}
		return "main";
	}//END OF FUNCTION

}//END OF CLASS