package javaxt.azure.graph;

import java.util.*;

import java.net.http.HttpClient;

import java.net.http.HttpRequest;

import java.net.http.HttpResponse;

import static java.nio.charset.StandardCharsets.*;

import javaxt.json.*;

import static javaxt.utils.Console.console;

public class Connection {

//Azure end-points

private String loginURL = "https://login.microsoftonline.com/{tenant}/oauth2/v2.0/token";

private String graphURL = "https://graph.microsoft.com/v1.0";

//Static properties

private String tenantID;

private String clientID;

private String clientSecret;

//Transient properties

private String tokenType;

private String accessToken;

private javaxt.utils.Date expirationDate;

//**************************************************************************

//** Constructor

//**************************************************************************

public Connection(String tenantID, String clientID, String clientSecret) throws Exception {

this.tenantID = tenantID;

this.clientID = clientID;

this.clientSecret = clientSecret;

connect();

}

//**************************************************************************

//** connect

//**************************************************************************

private void connect() throws Exception {

console.log("connecting...");

String loginURL = this.loginURL.replace("{tenant}", tenantID);

javaxt.http.Request request = new javaxt.http.Request(loginURL);

request.setNumRedirects(0);

String payload = "client_id=" +clientID +

"&scope=https%3A%2F%2Fgraph.microsoft.com%2F.default" +

"&client_secret=" + clientSecret +

"&grant_type=client_credentials";

//request.setHeader(); application/x-www-form-urlencoded

request.write(payload);

javaxt.http.Response response = request.getResponse();

JSONObject json = response.getJSONObject();

if (response.getStatus()==200){

tokenType = json.get("token_type").toString();

accessToken = json.get("access_token").toString();

Integer expiresIn = json.get("expires_in").toInteger();

expirationDate = new javaxt.utils.Date().add(expiresIn, "seconds");

console.log("Connected! token expires " + expirationDate);

}

else{

System.out.println(response.toString());

System.out.println(json.toString(4));

throw new Exception();

}

}

//**************************************************************************

//** getExpiration

//**************************************************************************

public javaxt.utils.Date getExpirationDate(){

return expirationDate;

}

//**************************************************************************

//** getResponse

//**************************************************************************

public JSONObject getResponse(String url) throws Exception {

return getResponse(url, null);

}

//**************************************************************************

//** getResponse

//**************************************************************************

public JSONObject getResponse(String url, JSONObject payload) throws Exception {

return getResponse(url, payload, null);

}

//**************************************************************************

//** getResponse

//**************************************************************************

public JSONObject getResponse(String url, JSONObject payload, String method) throws Exception {

//Get request builder

HttpRequest.Builder request = getRequest(url);

//Set payload and method as needed

if (payload!=null){

if (method==null) method = "POST";

else method = method.toUpperCase();

request.header("Content-Type", "application/json;charset=UTF-8");

request.method(method, HttpRequest.BodyPublishers.ofByteArray(

payload.toString().getBytes(UTF_8))

);

}

//Get response

HttpResponse<String> response = HttpClient.newBuilder()

.followRedirects(HttpClient.Redirect.NEVER)

.build()

.send(request.build(), HttpResponse.BodyHandlers.ofString(UTF_8));

//Parse and return response

JSONObject json = new JSONObject(response.body());

int status = response.statusCode();

if (status==200){

return json;

}

else if (status==429){

Thread.sleep(1500);

return getResponse(url);

}

else{

//console.log(response.headers().map());

//System.out.println(response.toString());

System.out.println(json.toString(4));

throw new Exception();

}

}

//**************************************************************************

//** getRequest

//**************************************************************************

private synchronized HttpRequest.Builder getRequest(String url) throws Exception {

//Update url as needed

if (!url.startsWith(graphURL) && !url.startsWith("http")){

if (!url.startsWith("/")) url = "/" + url;

url = graphURL + url;

}

//Refresh tokens as needed

var timeRemaining = expirationDate.compareTo(new javaxt.utils.Date(), "seconds");

//console.log("timeRemaining: " + timeRemaining + " seconds");

if (timeRemaining<60) connect();

//Execute http request and return response

return HttpRequest.newBuilder()

.uri(java.net.URI.create(url))

.header("Authorization", tokenType + " " + accessToken);

}

}