'use strict';

module.exports.dependencies = [ 'OAUTH3', 'storage.owners', 'options.device' ];
module.exports.create = function (deps, conf) {
  var scmp = require('scmp');
  var crypto = require('crypto');
  var jwt = require('jsonwebtoken');
  var bodyParser = require('body-parser');
  var jsonParser = bodyParser.json({
    inflate: true, limit: '100kb', reviver: null, strict: true /* type, verify */
  });

  var api = deps.api;

  /*
  var owners;
  deps.storage.owners.on('set', function (_owners) {
    owners = _owners;
  });
  */

  function handleCors(req, res, methods) {
    if (!methods) {
      methods = ['GET', 'POST'];
    }
    if (!Array.isArray(methods)) {
      methods = [ methods ];
    }

    res.setHeader('Access-Control-Allow-Origin', req.headers.origin || '*');
    res.setHeader('Access-Control-Allow-Methods', methods.join(', '));
    res.setHeader('Access-Control-Allow-Headers', 'Content-Type, Authorization');

    if (req.method.toUpperCase() !== 'OPTIONS') {
      return false;
    }

    res.setHeader('Allow', methods.join(', '));
    res.end();
    return true;
  }

  function isAuthorized(req, res, fn) {
    var auth = jwt.decode((req.headers.authorization||'').replace(/^bearer\s+/i, ''));
    if (!auth) {
      res.statusCode = 401;
      res.setHeader('Content-Type', 'application/json;');
      res.end(JSON.stringify({ error: { message: "no token", code: 'E_NO_TOKEN', uri: undefined } }));
      return;
    }

    var id = crypto.createHash('sha256').update(auth.sub).digest('hex');
    return deps.storage.owners.exists(id).then(function (exists) {
      if (!exists) {
        res.statusCode = 401;
        res.setHeader('Content-Type', 'application/json;');
        res.end(JSON.stringify({ error: { message: "not authorized", code: 'E_NO_AUTHZ', uri: undefined } }));
        return;
      }

      req.userId = id;
      fn();
    });
  }

  return {
    init: function (req, res) {
      if (handleCors(req, res, 'POST')) {
        return;
      }
      if (req.method !== 'POST') {
        res.statusCode = 405;
        res.setHeader('Content-Type', 'application/json');
        res.end(JSON.stringify({ error: { message: 'method '+req.method+' not allowed'}}));
        return;
      }

      jsonParser(req, res, function () {

      return deps.PromiseA.resolve().then(function () {
        console.log('init POST body', req.body);

        var auth = jwt.decode((req.headers.authorization||'').replace(/^bearer\s+/i, ''));
        var token = jwt.decode(req.body.access_token);
        var refresh = jwt.decode(req.body.refresh_token);
        auth.sub = auth.sub || auth.acx.id;
        token.sub = token.sub || token.acx.id;
        refresh.sub = refresh.sub || refresh.acx.id;

        // TODO validate token with issuer, but as-is the sub is already a secret
        var id = crypto.createHash('sha256').update(auth.sub).digest('hex');
        var tid = crypto.createHash('sha256').update(token.sub).digest('hex');
        var rid = crypto.createHash('sha256').update(refresh.sub).digest('hex');
        var session = {
          access_token: req.body.access_token
        , token: token
        , refresh_token: req.body.refresh_token
        , refresh: refresh
        };

        console.log('ids', id, tid, rid);

        if (req.body.ip_url) {
          // TODO set options / GunDB
          conf.ip_url = req.body.ip_url;
        }

        return deps.storage.owners.all().then(function (results) {
          console.log('results', results);
          var err;

          // There is no owner yet. First come, first serve.
          if (!results || !results.length) {
            if (tid !== id || rid !== id) {
              err = new Error(
                "When creating an owner the Authorization Bearer and Token and Refresh must all match"
              );
              err.statusCode = 400;
              return deps.PromiseA.reject(err);
            }
            console.log('no owner, creating');
            return deps.storage.owners.set(id, session);
          }
          console.log('has results');

          // There are onwers. Is this one of them?
          if (!results.some(function (token) {
            return scmp(id, token.id);
          })) {
            err = new Error("Authorization token does not belong to an existing owner.");
            err.statusCode = 401;
            return deps.PromiseA.reject(err);
          }
          console.log('has correct owner');

          // We're adding an owner, unless it already exists
          if (!results.some(function (token) {
            return scmp(tid, token.id);
          })) {
            console.log('adds new owner with existing owner');
            return deps.storage.owners.set(tid, session);
          }
        }).then(function () {
          res.setHeader('Content-Type', 'application/json;');
          res.end(JSON.stringify({ success: true }));
        });
      })
      .catch(function (err) {
        res.setHeader('Content-Type', 'application/json;');
        res.statusCode = err.statusCode || 500;
        res.end(JSON.stringify({ error: { message: err.message, code: err.code, uri: err.uri } }));
      });

      });
    }
  , tunnel: function (req, res) {
      if (handleCors(req, res)) {
        return;
      }
      isAuthorized(req, res, function () {
        if ('POST' !== req.method) {
          res.setHeader('Content-Type', 'application/json');
          return deps.tunnelClients.get(req.userId).then(function (result) {
            res.end(JSON.stringify(result));
          }, function (err) {
            res.statusCode = 500;
            res.end(JSON.stringify({ error: { message: err.message, code: err.code, uri: err.uri } }));
          });
        }

        return deps.storage.owners.get(req.userId).then(function (session) {
          return deps.tunnelClients.start(session).then(function () {
            res.setHeader('Content-Type', 'application/json;');
            res.end(JSON.stringify({ success: true }));
          }, function (err) {
            res.setHeader('Content-Type', 'application/json;');
            res.statusCode = 500;
            res.end(JSON.stringify({ error: { message: err.message, code: err.code, uri: err.uri } }));
          });
        });
      });
    }
  , config: function (req, res) {
      if (handleCors(req, res)) {
        return;
      }
      isAuthorized(req, res, function () {
        if ('POST' !== req.method) {
          res.setHeader('Content-Type', 'application/json;');
          res.end(JSON.stringify(deps.recase.snakeCopy(conf)));
          return;
        }

        jsonParser(req, res, function () {
          console.log('config POST body', req.body);

          // Since we are sending the changes to another process we don't really
          // have a good way of seeing if it worked, so always report success
          deps.storage.config.save(req.body);
          res.setHeader('Content-Type', 'application/json;');
          res.end('{"success":true}');
        });
      });
    }
  , request: function (req, res) {
      if (handleCors(req, res, '*')) {
        return;
      }
      isAuthorized(req, res, function () {
      jsonParser(req, res, function () {

        deps.request({
          method: req.body.method || 'GET'
        , url: req.body.url
        , headers: req.body.headers
        , body: req.body.data
        }).then(function (resp) {
          if (resp.body instanceof Buffer || 'string' === typeof resp.body) {
            resp.body = JSON.parse(resp.body);
          }

          return {
            statusCode: resp.statusCode
          , status: resp.status
          , headers: resp.headers
          , body: resp.body
          , data: resp.data
          };
        }).then(function (result) {
          res.send(result);
        });

      });
      });
    }
  , _api: api
  };
};