'use strict';

let Cookies = require('cookies');
let express = require('express');
let bodyParser = require('body-parser');
let Error = require('http-errors');
let Path = require('path');
let Middleware = require('./middleware');
let Notify = require('./notify');
let Utils = require('./utils');
let expect_json = Middleware.expect_json;
let match = Middleware.match;
let media = Middleware.media;
let validate_name = Middleware.validate_name;
let validate_pkg = Middleware.validate_package;

module.exports = function(config, auth, storage) {
  let app = express.Router();
  let can = Middleware.allow(auth);
  let notify = Notify.notify;

  // validate all of these params as a package name
  // this might be too harsh, so ask if it causes trouble
  app.param('package', validate_pkg);
  app.param('filename', validate_name);
  app.param('tag', validate_name);
  app.param('version', validate_name);
  app.param('revision', validate_name);
  app.param('token', validate_name);

  // these can't be safely put into express url for some reason
  app.param('_rev', match(/^-rev$/));
  app.param('org_couchdb_user', match(/^org\.couchdb\.user:/));
  app.param('anything', match(/.*/));

  app.use(auth.basic_middleware());
  // app.use(auth.bearer_middleware())
  app.use(bodyParser.json({strict: false, limit: config.max_body_size || '10mb'}));
  app.use(Middleware.anti_loop(config));

  // encode / in a scoped package name to be matched as a single parameter in routes
  app.use(function(req, res, next) {
    if (req.url.indexOf('@') != -1) {
      // e.g.: /@org/pkg/1.2.3 -> /@org%2Fpkg/1.2.3, /@org%2Fpkg/1.2.3 -> /@org%2Fpkg/1.2.3
      req.url = req.url.replace(/^(\/@[^\/%]+)\/(?!$)/, '$1%2F');
    }
    next();
  });

  // for "npm whoami"
  app.get('/whoami', function(req, res, next) {
    if (req.headers.referer === 'whoami') {
      next({username: req.remote_user.name});
    } else {
      next('route');
    }
  });
  app.get('/-/whoami', function(req, res, next) {
    next({username: req.remote_user.name});
  });

  // TODO: anonymous user?
  app.get('/:package/:version?', can('access'), function(req, res, next) {
    storage.get_package(req.params.package, {req: req}, function(err, info) {
      if (err) return next(err);
      info = Utils.filter_tarball_urls(info, req, config);

      let version = req.params.version;
      if (!version) return next(info);

      let t = Utils.get_version(info, version);
      if (t != null) return next(t);

      if (info['dist-tags'] != null) {
        if (info['dist-tags'][version] != null) {
          version = info['dist-tags'][version];
          t = Utils.get_version(info, version);
          if (t != null) return next(t);
        }
      }

      return next( Error[404]('version not found: ' + req.params.version) );
    });
  });

  app.get('/:package/-/:filename', can('access'), function(req, res, next) {
    let stream = storage.get_tarball(req.params.package, req.params.filename);
    stream.on('content-length', function(v) {
      res.header('Content-Length', v);
    });
    stream.on('error', function(err) {
      return res.report_error(err);
    });
    res.header('Content-Type', 'application/octet-stream');
    stream.pipe(res);
  });

  // searching packages
  app.get('/-/all(\/since)?', function(req, res, next) {
    let received_end = false;
    let response_finished = false;
    let processing_pkgs = 0;
    let firstPackage = true;

    res.status(200);

    /*
     * Offical NPM registry (registry.npmjs.org) no longer return whole database,
     * They only return packages matched with keyword in `referer: search pkg-name`,
     * And NPM client will request server in every search.
     *
     * The magic number 99999 was sent by NPM registry. Modify it may caused strange
     * behaviour in the future.
     *
     * BTW: NPM will not return result if user-agent does not contain string 'npm',
     * See: method 'request' in up-storage.js
     *
     * If there is no cache in local, NPM will request /-/all, then get response with
     * _updated: 99999, 'Date' in response header was Mon, 10 Oct 1983 00:12:48 GMT,
     * this will make NPM always query from server
     *
     * Data structure also different, whel request /-/all, response is an object, but
     * when request /-/all/since, response is an array
    */
    const respShouldBeArray = req.path.endsWith('/since');
    res.set('Date', 'Mon, 10 Oct 1983 00:12:48 GMT');

    if (respShouldBeArray) {
      res.write('[');
    } else {
      res.write('{"_updated":' + 99999);
    }

    let stream = storage.search(req.query.startkey || 0, {req: req});

    stream.on('data', function each(pkg) {
      processing_pkgs++;

      auth.allow_access(pkg.name, req.remote_user, function(err, allowed) {
        processing_pkgs--;

        if (err) {
          if (err.status && String(err.status).match(/^4\d\d$/)) {
            // auth plugin returns 4xx user error,
            // that's equivalent of !allowed basically
            allowed = false;
          } else {
            stream.abort(err);
          }
        }

        if (allowed) {
          if (respShouldBeArray) {
            res.write(`${firstPackage ? '' : ','}${JSON.stringify(pkg)}\n`);
            if (firstPackage) {
              firstPackage = false;
            }
          } else {
            res.write(',\n' + JSON.stringify(pkg.name) + ':' + JSON.stringify(pkg));
          }
        }

        check_finish();
      });
    });

    stream.on('error', function(_err) {
      res.socket.destroy();
    });

    stream.on('end', function() {
      received_end = true;
      check_finish();
    });

    function check_finish() {
      if (!received_end) return;
      if (processing_pkgs) return;
      if (response_finished) return;

      response_finished = true;
      if (respShouldBeArray) {
        res.end(']\n');
      } else {
        res.end('}\n');
      }
    }
  });

  // placeholder 'cause npm require to be authenticated to publish
  // we do not do any real authentication yet
  app.post('/_session', Cookies.express(), function(req, res, next) {
    res.cookies.set('AuthSession', String(Math.random()), {
      // npmjs.org sets 10h expire
      expires: new Date(Date.now() + 10*60*60*1000),
    });
    next({ok: true, name: 'somebody', roles: []});
  });

  app.get('/-/user/:org_couchdb_user', function(req, res, next) {
    res.status(200);
    next({
      ok: 'you are authenticated as "' + req.remote_user.name + '"',
    });
  });

  app.put('/-/user/:org_couchdb_user/:_rev?/:revision?', function(req, res, next) {
    let token = (req.body.name && req.body.password)
              ? auth.aes_encrypt(req.body.name + ':' + req.body.password).toString('base64')
              : undefined;
    if (req.remote_user.name != null) {
      res.status(201);
      return next({
        ok: 'you are authenticated as \'' + req.remote_user.name + '\'',
        // token: auth.issue_token(req.remote_user),
        token: token,
      });
    } else {
      if (typeof(req.body.name) !== 'string' || typeof(req.body.password) !== 'string') {
        if (typeof(req.body.password_sha)) {
          return next( Error[422]('your npm version is outdated\nPlease update to npm@1.4.5 or greater.\nSee https://github.com/rlidwka/sinopia/issues/93 for details.') );
        } else {
          return next( Error[422]('user/password is not found in request (npm issue?)') );
        }
      }
      auth.add_user(req.body.name, req.body.password, function(err, user) {
        if (err) {
          if (err.status >= 400 && err.status < 500) {
            // With npm registering is the same as logging in,
            // and npm accepts only an 409 error.
            // So, changing status code here.
            return next( Error[409](err.message) );
          }
          return next(err);
        }

        req.remote_user = user;
        res.status(201);
        return next({
          ok: 'user \'' + req.body.name + '\' created',
          // token: auth.issue_token(req.remote_user),
          token: token,
        });
      });
    }
  });

  app.delete('/-/user/token/*', function(req, res, next) {
    res.status(200);
    next({
      ok: 'Logged out',
    });
  });

  function tag_package_version(req, res, next) {
    if (typeof(req.body) !== 'string') return next('route');

    let tags = {};
    tags[req.params.tag] = req.body;
    storage.merge_tags(req.params.package, tags, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'package tagged'});
    });
  }

  // tagging a package
  app.put('/:package/:tag',
      can('publish'), media('application/json'), tag_package_version);

  app.post('/-/package/:package/dist-tags/:tag',
      can('publish'), media('application/json'), tag_package_version);

  app.put('/-/package/:package/dist-tags/:tag',
      can('publish'), media('application/json'), tag_package_version);

  app.delete('/-/package/:package/dist-tags/:tag', can('publish'), function(req, res, next) {
    let tags = {};
    tags[req.params.tag] = null;
    storage.merge_tags(req.params.package, tags, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'tag removed'});
    });
  });

  app.get('/-/package/:package/dist-tags', can('access'), function(req, res, next) {
    storage.get_package(req.params.package, {req: req}, function(err, info) {
      if (err) return next(err);

      next(info['dist-tags']);
    });
  });

  app.post('/-/package/:package/dist-tags',
      can('publish'), media('application/json'), expect_json,
      function(req, res, next) {
    storage.merge_tags(req.params.package, req.body, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'tags updated'});
    });
  });

  app.put('/-/package/:package/dist-tags',
      can('publish'), media('application/json'), expect_json,
      function(req, res, next) {
    storage.replace_tags(req.params.package, req.body, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'tags updated'});
    });
  });

  app.delete('/-/package/:package/dist-tags',
      can('publish'), media('application/json'),
      function(req, res, next) {
    storage.replace_tags(req.params.package, {}, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'tags removed'});
    });
  });

  // publishing a package
  app.put('/:package/:_rev?/:revision?', can('publish'), media('application/json'), expect_json, function(req, res, next) {
    let name = req.params.package;

    if (Object.keys(req.body).length == 1 && Utils.is_object(req.body.users)) {
      // 501 status is more meaningful, but npm doesn't show error message for 5xx
      return next( Error[404]('npm star|unstar calls are not implemented') );
    }

    try {
      var metadata = Utils.validate_metadata(req.body, name);
    } catch(err) {
      return next( Error[422]('bad incoming package data') );
    }

    if (req.params._rev) {
      storage.change_package(name, metadata, req.params.revision, function(err) {
        after_change(err, 'package changed');
      });
    } else {
      storage.add_package(name, metadata, function(err) {
        after_change(err, 'created new package');
      });
    }

    function after_change(err, ok_message) {
      // old npm behaviour
      if (metadata._attachments == null) {
        if (err) return next(err);
        res.status(201);
        return next({ok: ok_message});
      }

      // npm-registry-client 0.3+ embeds tarball into the json upload
      // https://github.com/isaacs/npm-registry-client/commit/e9fbeb8b67f249394f735c74ef11fe4720d46ca0
      // issue #31, dealing with it here:

      if (typeof(metadata._attachments) !== 'object'
      || Object.keys(metadata._attachments).length !== 1
      || typeof(metadata.versions) !== 'object'
      || Object.keys(metadata.versions).length !== 1) {
        // npm is doing something strange again
        // if this happens in normal circumstances, report it as a bug
        return next( Error[400]('unsupported registry call') );
      }

      if (err && err.status != 409) return next(err);

      // at this point document is either created or existed before
      let t1 = Object.keys(metadata._attachments)[0];
      create_tarball(Path.basename(t1), metadata._attachments[t1], function(err) {
        if (err) return next(err);

        let t2 = Object.keys(metadata.versions)[0];
        metadata.versions[t2].readme = metadata.readme != null ? String(metadata.readme) : '';
        create_version(t2, metadata.versions[t2], function(err) {
          if (err) return next(err);

          add_tags(metadata['dist-tags'], function(err) {
            if (err) return next(err);
            notify(metadata, config);
            res.status(201);
            return next({ok: ok_message});
          });
        });
      });
    }

    function create_tarball(filename, data, cb) {
      let stream = storage.add_tarball(name, filename);
      stream.on('error', function(err) {
        cb(err);
      });
      stream.on('success', function() {
        cb();
      });

      // this is dumb and memory-consuming, but what choices do we have?
      stream.end(new Buffer(data.data, 'base64'));
      stream.done();
    }

    function create_version(version, data, cb) {
      storage.add_version(name, version, data, null, cb);
    }

    function add_tags(tags, cb) {
      storage.merge_tags(name, tags, cb);
    }
  });

  // unpublishing an entire package
  app.delete('/:package/-rev/*', can('publish'), function(req, res, next) {
    storage.remove_package(req.params.package, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'package removed'});
    });
  });

  // removing a tarball
  app.delete('/:package/-/:filename/-rev/:revision', can('publish'), function(req, res, next) {
    storage.remove_tarball(req.params.package, req.params.filename, req.params.revision, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'tarball removed'});
    });
  });

  // uploading package tarball
  app.put('/:package/-/:filename/*', can('publish'), media('application/octet-stream'), function(req, res, next) {
    let name = req.params.package;

    let stream = storage.add_tarball(name, req.params.filename);
    req.pipe(stream);

    // checking if end event came before closing
    let complete = false;
    req.on('end', function() {
      complete = true;
      stream.done();
    });
    req.on('close', function() {
      if (!complete) {
        stream.abort();
      }
    });

    stream.on('error', function(err) {
      return res.report_error(err);
    });
    stream.on('success', function() {
      res.status(201);
      return next({
        ok: 'tarball uploaded successfully',
      });
    });
  });

  // adding a version
  app.put('/:package/:version/-tag/:tag', can('publish'), media('application/json'), expect_json, function(req, res, next) {
    let name = req.params.package;
    let version = req.params.version;
    let tag = req.params.tag;

    storage.add_version(name, version, req.body, tag, function(err) {
      if (err) return next(err);
      res.status(201);
      return next({ok: 'package published'});
    });
  });

  return app;
};