/**
 * ============LICENSE_START====================================================
 * org.onap.aaf
 * ===========================================================================
 * Copyright (c) 2018 AT&T Intellectual Property. All rights reserved.
 * ===========================================================================
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * ============LICENSE_END====================================================
 *
 */

package org.onap.aaf.cadi.enduser.test;

import java.io.IOException;
import java.net.ConnectException;
import java.security.GeneralSecurityException;
import java.util.Date;
import java.util.GregorianCalendar;

import org.onap.aaf.cadi.Access.Level;
import org.onap.aaf.cadi.CadiException;
import org.onap.aaf.cadi.LocatorException;
import org.onap.aaf.cadi.PropAccess;
import org.onap.aaf.cadi.aaf.Defaults;
import org.onap.aaf.cadi.client.Future;
import org.onap.aaf.cadi.client.Rcli;
import org.onap.aaf.cadi.client.Result;
import org.onap.aaf.cadi.client.Retryable;
import org.onap.aaf.cadi.config.Config;
import org.onap.aaf.cadi.oauth.TimedToken;
import org.onap.aaf.cadi.oauth.TokenClient;
import org.onap.aaf.cadi.oauth.TokenClientFactory;
import org.onap.aaf.cadi.oauth.TzClient;
import org.onap.aaf.cadi.util.FQI;
import org.onap.aaf.misc.env.APIException;
import org.onap.aaf.misc.env.util.Chrono;

import aafoauth.v2_0.Introspect;
import aafoauth.v2_0.Token;


public class OnapClientExample {
	private static TokenClientFactory tcf;
	private static PropAccess access;

	public final static void main(final String args[]) {
		// These Objects are expected to be Long-Lived... Construct once
		
		// Property Access
		// This method will allow you to set "cadi_prop_files" (or any other property) on Command line 
		access = new PropAccess(args);
		
		// access = PropAccess();
		// Note: This style will load "cadi_prop_files" from VM Args
		
		// Token aware Client Factory
		try {
			tcf = TokenClientFactory.instance(access);
		} catch (APIException | GeneralSecurityException | IOException | CadiException e1) {
			access.log(e1, "Unable to setup OAuth Client Factory, Fail Fast");
			System.exit(1);
		}
		
		final int CALL_TIMEOUT = Integer.parseInt(access.getProperty(Config.AAF_CALL_TIMEOUT,Config.AAF_CALL_TIMEOUT_DEF));
		
		try {
			//////////////////////////////////////////////////////////////////////
			// Scenario 1:
			// Get and use an OAuth Client, which understands Token Management
			//////////////////////////////////////////////////////////////////////
			// Create a Token Client, that gets its tokens from expected OAuth Server
			//   In this example, it is AAF, but it can be the Alternate OAuth

			TokenClient tc = tcf.newClient(Config.AAF_OAUTH2_TOKEN_URL); // can set your own timeout here (url, timeoutMilliseconds)
			
			// Here's a trick to get the namespace out of a Fully Qualified AAF Identity (your MechID)
			String ns = FQI.reverseDomain(tc.client_id());
			System.out.printf("\nNote: The AAF Namespace of FQI (Fully Qualified Identity) %s is %s\n\n",tc.client_id(), ns);

			// Now, we can get a Token.  Note: for "scope", use AAF Namespaces to get AAF Permissions embedded in
			// Note: getToken checks if Token is expired, if so, then refreshes before handing back.
			Result<TimedToken> rtt = tc.getToken(ns,"org.onap.test"); // get multiple scopes
			
			// Note: you can clear a Token's Disk/Memory presence by
			//  1) removing the Token from the "token/outgoing" directory on the O/S
			//  2) programmatically by calling "clearToken" with exact params as "getToken", when it has the same credentials set
			//       tc.clearToken("org.onap.aaf","org.onap.test");
			
			// Result Object can be queried for success
			if(rtt.isOK()) {
				TimedToken token = rtt.value;
				print(token); // Take a look at what's in a Token
				
				// Use this Token in your client calls with "Tokenized Client" (TzClient)
				// These should NOT be used cross thread.
				// Get Hello Service URL... roll your own in your own world.
				final String endServicesURL = access.getProperty(Config.AAF_OAUTH2_HELLO_URL,Defaults.HELLO_URL);


				TzClient helloClient = tcf.newTzClient(endServicesURL);
				helloClient.setToken(tc.client_id(), token);
				
				// This client call style, "best" call with "Retryable" inner class covers finding an available Service 
				// (when Multi-services exist) for the best service, based (currently) on distance.
				//
				// the "Generic" in Type gives a Return Value for the Code, which you can set on the "best" method
				// Note that variables used in the inner class from this part of the code must be "final", see "CALL_TIMEOUT"
				String rv = helloClient.best(new Retryable<String>() {
					@Override
					public String code(Rcli<?> client) throws CadiException, ConnectException, APIException {
						Future<String> future = client.read("hello","text/plain");
						// The "future" calling method allows you to do other processing, such as call more than one backend
						// client before picking up the result
						// If "get" matches the HTTP Code for the method (i.e. read HTTP Return value is 200), then 
						if(future.get(CALL_TIMEOUT)) {
							// Client Returned expected value
							return future.value;
						} else {
							throw new APIException(future.code()  + future.body());
						}					
					}
				});
				
				// You want to do something with returned value.  Here, we say "hello"
				System.out.printf("\nPositive Response from Hello: %s\n",rv);
				
				
				//////////////////////////////////////////////////////////////////////
				// Scenario 2:
				// As a Service, read Introspection information as proof of Authenticated Authorization
				//////////////////////////////////////////////////////////////////////
				// CADI Framework (i.e. CadiFilter) works with the Introspection to drive the J2EE interfaces (
				// i.e. if(isUserInRole("ns.perm|instance|action")) {...
				//
				// Here, however, is a way to introspect via Java
				//
				// now, call Introspect (making sure right URLs are set in properties)
				// We need a Different Introspect TokenClient, because different Endpoint (and usually different Services)
				TokenClient tci = tcf.newClient(Config.AAF_OAUTH2_INTROSPECT_URL);
				Result<Introspect> is = tci.introspect(token.getAccessToken());
				if(is.isOK()) {
					// Note that AAF will add JSON set of Permissions as part of "Content:", legitimate extension of OAuth Structure
					print(is.value); // do something with Introspect Object
				} else {
					access.printf(Level.ERROR, "Unable to introspect OAuth Token %s: %d %s\n",
							token.getAccessToken(),rtt.code,rtt.error);
				}
			} else {
				access.printf(Level.ERROR, "Unable to obtain OAuth Token: %d %s\n",rtt.code,rtt.error);
			}
			
		} catch (CadiException | LocatorException | APIException | IOException e) {
			e.printStackTrace();
		}
	}
	
	/////////////////////////////////////////////////////////////
	// Examples of Object Access
	/////////////////////////////////////////////////////////////
	private static void print(Token t) {
		GregorianCalendar exp_date = new GregorianCalendar();
		exp_date.add(GregorianCalendar.SECOND, t.getExpiresIn());
		System.out.printf("Access Token\n\tToken:\t\t%s\n\tToken Type:\t%s\n\tExpires In:\t%d (%s)\n\tScope:\t\t%s\n\tRefresh Token:\t%s\n",
		t.getAccessToken(),
		t.getTokenType(),
		t.getExpiresIn(),
		Chrono.timeStamp(new Date(System.currentTimeMillis()+(t.getExpiresIn()*1000))),
		t.getScope(),
		t.getRefreshToken());
	}
	
	private static void print(Introspect ti) {
		if(ti==null || ti.getClientId()==null) {
			System.out.println("Empty Introspect");
			return;
		}
		Date exp = new Date(ti.getExp()*1000); // seconds
		System.out.printf("Introspect\n"
				+ "\tAccessToken:\t%s\n"
				+ "\tClient-id:\t%s\n"
				+ "\tClient Type:\t%s\n"
				+ "\tActive:  \t%s\n"
				+ "\tUserName:\t%s\n"
				+ "\tExpires: \t%d (%s)\n"
				+ "\tScope:\t\t%s\n"
				+ "\tContent:\t%s\n",
		ti.getAccessToken(),
		ti.getClientId(),
		ti.getClientType(),
		ti.isActive()?Boolean.TRUE.toString():Boolean.FALSE.toString(),
		ti.getUsername(),
		ti.getExp(),
		Chrono.timeStamp(exp),
		ti.getScope(),
		ti.getContent()==null?"":ti.getContent());
		
		System.out.println();
	}

}