var express = require('express');
var bodyParser = require('body-parser');
var assert = require('assert');
var MongoClient = require('mongodb').MongoClient;
var ObjectID = require('mongodb').ObjectID;
var createHash = require('./hash.js').createHash;
var createRandomBytes = require('./hash.js').createRandomBytes;

var http = require('http');
var fs = require('fs');
var mkdirp = require('mkdirp');
var zlib = require('zlib');
var download = require('download');
var readline = require('readline');

// Global vars
var app = express();
var mongoUrl = 'mongodb://miyava.de:27017/Miyava';

// Session object
var sessions = {};

// Middleware
app.use(bodyParser.json());

// Authorize middleware
app.use(function(req, res, next) {
    req.is_authorized = false;
    if(req.body.session_id == null) {
        req.authorized_error = { error: 'Not logged in' };
    }
    else {
        var user = sessions[req.body.session_id];
        if(user == null) {
            req.authorized_error = { error: 'Session invalid' };
        }
        else {
            req.is_authorized = true;
        }
    }
    next();
});

// Used to register a user
app.post('/register', function(req, res) {
    assert.notEqual(req.body.username, undefined);
    assert.notEqual(req.body.password, undefined);

    MongoClient.connect(mongoUrl, function(err, db) {
        assert.equal(err, null);

        db.collection('users', function(err, collection) {
            assert.equal(err, null);

            var hash = createHash(req.body.password);
            collection.insertOne({username: req.body.username, password: hash, firstname: req.body.firstname, lastname: req.body.lastname, roles: ['user'] }, function(err, result) {
                assert.equal(err, null);
                res.send(result);
                db.close();
            });
        });
    });
});

// Used to login as a specified user
app.post('/login', function(req, res) {
    assert.notEqual(req.body.username, undefined);
    assert.notEqual(req.body.password, undefined);

    MongoClient.connect(mongoUrl, function(err, db) {
        assert.equal(err, null);

        db.collection('users', function(err, collection) {
            assert.equal(err, null);

            var sessionBase = req.body.username + '_' + Date.now() + '_' + createRandomBytes();
            var sessionId = createHash(sessionBase);

            collection.findOneAndUpdate({username: req.body.username}, { '$set': { 'session_id': sessionId } }, { upsert: false }, function(err, document) {
                assert.equal(err, null);

                if(document.value == null) {
                    res.send('{"error":"Username does not exist"}');
                }
                else {
                    var hash = createHash(req.body.password);
                    if(document.value.password == hash) {
                        var user = {
                            id: document.value._id,
                            username: document.value.username,
                            session_id: document.value.session_id,
                            firstname: document.value.firstname,
                            lastname: document.value.lastname,
                            roles: document.value.roles
                        };

                        sessions[user.session_id] = user;
                        res.send(user);
                    }
                    else {
                        res.send({success: false, error: 'Password is wrong'});
                    }
                }
                db.close();
            });
        });
    });
});

app.post('/logout', function(req, res) {
    if(!req.is_authorized) {
        res.send(req.authorized_error);
    }
    else {
        MongoClient.connect(mongoUrl, function(err, db) {
            assert.equal(err, null);

            db.collection('users', function(err, collection) {
                assert.equal(err, null);

                var user = sessions[req.body.session_id];
                collection.findOneAndUpdate({_id: user.id}, { '$unset': { 'session_id': '' } }, { upsert: false }, function(err, document) {
                    assert.equal(err, null);

                    if(document.value == null) {
                        res.send({success: false, error: 'Unknown error'});
                    }
                    else {
                        res.send({success: true});
                    }
                    db.close();
                });
            });
        });
    }
});

// List all users (if logged in atleast :D)
app.post('/users', function(req, res) {
    if(!req.is_authorized) {
        res.send(req.authorized_error);
    }
    else {
        var user = sessions[req.body.session_id];
        if(user.roles === undefined || !user.roles.includes('user')) {
            res.send('{"error":"User does not have enough roles"}');
        }
        else {
            MongoClient.connect(mongoUrl, function(err, db) {
                assert.equal(err, null);

                db.collection('users', function(err, collection) {
                    assert.equal(err, null);

                    collection.find({}).toArray(function(err, documents) {
                        assert.equal(err, null);

                        res.send(documents);
                        db.close();
                    });
                });
            });
        }
    }
});

// DEV ONLY :D
app.get('/users', function(req, res) {
    MongoClient.connect(mongoUrl, function(err, db) {
        assert.equal(err, null);

        db.collection('users', function(err, collection) {
            assert.equal(err, null);

            collection.find({}).toArray(function(err, documents) {
                assert.equal(err, null);

                res.send(documents);
                db.close();
            });
        });
    });
});

app.get('/movies', function(req, res){
    MongoClient.connect(mongoUrl, function(err, db) {
        assert.equal(err, null);

        db.collection('movies', function(err, collection) {
            assert.equal(err, null);

            collection.find({}).toArray(function(err, documents) {
                assert.equal(err, null);

                res.send(documents);
                db.close();
            });
        });
    });
});

app.get('/movies_ids', function(req, res){
    MongoClient.connect(mongoUrl, function(err, db) {
        assert.equal(err, null);

        db.collection('movies_ids', function(err, collection) {
            assert.equal(err, null);

            collection.find({}).toArray(function(err, documents) {
                assert.equal(err, null);

                res.send(documents);
                db.close();
            });
        });
    });
});

app.get('/movies/:id/delete', function(req, res) {
    MongoClient.connect(mongoUrl, function(err, db) {
        assert.equal(err, null);

        db.collection('movies', function(err, collection) {
            assert.equal(err, null);

            collection.remove({_id: ObjectID(req.params.id)}, function(err, result) {
                if (err) {
                    console.log(err);
                }
                console.log(result);
                db.close();
            });
        });
    });
});


app.get('/movies/startDownload',function(req,res){
    var downloadDir ='./download';
    mkdirSync(downloadDir);
    var movieDir = './download/movie';
    mkdirSync(movieDir);

    if (!fs.existsSync('download/movie/movie_ids_04_28_2017.json.gz')) {
        downloadFile("http://files.tmdb.org/p/exports/movie_ids_04_28_2017.json.gz","download/movie/");
    }

    if (!fs.existsSync('movie_ids_04_28_2017.json')) {
        unzipFile(dest + "/movie_ids_04_28_2017.json.gz", "movie_ids_04_28_2017.json");

    }

    var myInterface = readline.createInterface({
        input: fs.createReadStream("movie_ids_04_28_2017.json")
    });

    myInterface.on('line', function (line) {
        var fileLine = JSON.parse(line);
        var notFind = false;
        MongoClient.connect(mongoUrl, function(err, db) {
            if (err) throw err;
            var query = { id: fileLine.id };

            db.collection("movies_ids").find(query).toArray(function(err, result) {
                if (err) throw err;
                if(result == null || result.length == 0){
                    notFind = true;
                } else {
                    notFind = false;
                }
            });
        });

        setTimeout(function() {
            if(notFind){
                MongoClient.connect(mongoUrl, function(err, db) {
                    if (err) throw err;
                    var query = { id: fileLine.id };
                    console.log(query);
                    db.collection('movies_ids', function(err, collection) {
                        assert.equal(err, null);
                        collection.insertOne({
                            adult:fileLine.adult,
                            id:fileLine.id,
                            original_title:fileLine.original_title,
                            popularity:fileLine.popularity,
                            video:fileLine.video
                        }, function(err, result) {
                            assert.equal(err, null);
                            res.send(result);
                        });
                    });
                    db.close();
                });
            }
        }, 3000);
        //process.exit();
    });
});

  function mkdirSync (dirPath) {
      if (!fs.existsSync(dirPath)){
          fs.mkdirSync(dirPath);
      }
  }

  function downloadFile(url, dest) {
      console.log("start Download");
      // for download more then one file
      Promise.all([
          url
      ].map(x => download(x, dest))).then(() => {
          console.log('files downloaded!');
          unzipFile(dest + "/movie_ids_04_28_2017.json.gz", "movie_ids_04_28_2017.json");
          readFileLineByLine(dest + "/movie_ids_04_28_2017.json");
      });

  }

  function unzipFile(dir, name) {
      const gzip = zlib.Unzip();

      const inp = fs.createReadStream(dir);
      const out = fs.createWriteStream(name);

      inp.pipe(gzip).pipe(out);
  }

app.listen(3500, '0.0.0.0');