const axios = require('axios');
var express = require("express");
var bodyParser = require("body-parser");

var PropertiesReader = require('properties-reader');
var properties = PropertiesReader('./properties.file');
var app = express();
var http = null;

const ParserUtils = require("./parsers/ParserUtils");
let resolverAPI = properties.get('PIDMR_API_URL')
const url = require('url');
const utils = new ParserUtils();

// Properties
if (properties.get('ssl')) {
  http = require("https");
} else {
  http = require("http");
}

app.use(bodyParser.json());
app.use(bodyParser.urlencoded({extended: true}));


app.use(function (req, res, next) {
  res.header('Access-Control-Allow-Origin', req.headers.origin);
  res.header('Access-Control-Allow-Headers', 'Origin, X-Requested-With, Content-Type, Accept, x-xsrf-token');
  res.header('Access-Control-Allow-Credentials', "true");
  res.header('Access-Control-Allow-Methods', 'GET, OPTIONS, POST, DELETE');
  res.header('Access-Control-Max-Age', "1800");
  next();
});

app.get('/:pid', function (req, res) {
  const pid = req.params.pid;
  let requestUrl = resolverAPI + pid;
  console.log("PIDMR url : " + requestUrl);
  axios.get(requestUrl)
    .then(function (response) {
      // handle success
      // console.log("status:", response.status, response.data.error);
      if (response.status != 200 || response.data.error) {
        res.status(response.data.error ? 500 : response.status).json({
          code: response.data.error ? 500 : response.status,
          message: response.data.error ? response.data.error : ("An error occurred while resolving pid " + pid + ".  ")
        });
        return;
      }

      const finalUrl = response.request.res.responseUrl;
      // Parse the URL to extract the host
      const parsedUrl = new url.URL(finalUrl);
      const finalHost = parsedUrl.host;
      /*if(finalHost.indexOf("pidmr.") != -1 ){
        res.status(500).json({

          status: response.status,
          message: "An error occurred while resolving pid " + pid + (response.data ? " - " + JSON.stringify(response.data) :"")
        });
        return;
      }*/

      console.log('Final Redirected URL:', finalUrl);
      console.log('Final Host:', finalHost);
      if (utils.getSupportedParsers().indexOf(finalHost) == -1) {
        console.log(finalHost + ": This endpoint is not supported for parsing");
        res.status(404).json({
          code: 404,
          message: "This endpoint is not supported for parsing."
        });
        return;
      }
      if (utils.getXMLParsers().indexOf(finalHost) != -1) {
        utils.parseXML(pid, finalHost, response.data).then(entity => {
          res.status(200).json(entity);
        })
      } else {
        let entity = utils.parseJSON(pid, finalHost, response.data)
        if (entity) {
          res.status(200).json(entity);
        } else {
          console.log("An error occurred while parsing from " + finalHost + " pid " + pid);
          res.status(500).json({
            code: 500,
            message: "An error occurred while parsing from " + finalHost + " pid " + pid
          });
        }
      }

    })
    .catch(function (error) {
      console.log(error.response.status, error.response.data.errorCode)
      res.status(error.response.data.errorCode ? error.response.data.errorCode : error.response.status).json(
        (error.response.data ? error.response.data : {
          code: error.response.code,
          message: "An error occurred while resolving pid:" + pid
        }));
      return
    })
    .finally(function () {
      // always executed
    });

});
app.get('/supported-endpoints', function (req, res) {
  res.status(200).json(utils.getSupportedParsers());
});

const server = app.listen(properties.get('port'), function () {
  console.log("Listening on port %s...", server.address().port);
});