refactor

4 files changed, 251 insertions, 203 deletions

diff --git a/index.js b/index.js
index d9d14df..5e39bf9 100644
--- a/index.js
+++ b/index.js
@@ -22,212 +22,19 @@
 //   _error.apply(null, args)
 // }
 
-var $ = require('jquery')
-var async = require('async')
-var bncode = require('bncode')
-var DHT = require('bittorrent-dht')
-var hat = require('hat')
-var magnet = require('magnet-uri')
-var portfinder = require('chrome-portfinder')
-var Swarm = require('bittorrent-swarm')
-
-var MAX_PEERS = 200
-var WIRE_TIMEOUT = 10000
-var METADATA_BLOCK_SIZE = 16 * 1024
+var TorrentManager = require('./lib/TorrentManager')
 
 var isChromeApp = !!(typeof window !== 'undefined' && window.chrome &&
     window.chrome.app && window.chrome.app.runtime)
 if (isChromeApp)
   console.log('This is a chrome app.')
 
-var peerId = '-WW0001-' + hat(48)
-
-function magnetToInfoHash (uri) {
-  try {
-    return magnet(uri).xt.split('urn:btih:')[1]
-  } catch (e) {
-    return null
-  }
-}
-
-function magnetToDisplayName (uri) {
-  try {
-    return magnet(uri).dn
-  } catch (e) {
-    return null
-  }
-}
-
-var magnetUri = 'magnet:?xt=urn:btih:d2474e86c95b19b8bcfdb92bc12c9d44667cfa36&dn=Leaves+of+Grass+by+Walt+Whitman.epub'
-var infoHash = magnetToInfoHash(magnetUri)
-var displayName = magnetToDisplayName(magnetUri)
-
-$('.infoHash span').text(infoHash)
-$('.displayName span').text(displayName)
-
-var dht
-var swarm
-
-async.auto({
-  dhtPort: function (cb) {
-    portfinder.getPort(cb)
-  },
-  swarmPort: function (cb) {
-    portfinder.getPort(cb)
-  },
-  dht: ['dhtPort', function (cb, r) {
-    dht = new DHT(infoHash)
-
-    dht.on('node', function (node, infoHash) {
-      var num = Number($('.dhtNodes span').text())
-      $('.dhtNodes span').text(num + 1)
-    })
-
-    dht.on('peer', function (peer, infoHash) {
-      var num = Number($('.dhtPeers span').text())
-      $('.dhtPeers span').text(num + 1)
-      // console.log('peer: ' + peer)
-
-      swarm.add(peer)
-    })
-
-    dht.findPeers(MAX_PEERS) // TODO: should the DHT be concerned with max peers?
-
-    // TODO: DHT should listen
-    // dht.listen(r.dhtPort)
-  }],
-  swarm: ['swarmPort', function (cb, r) {
-    swarm = new Swarm(infoHash, peerId, { dht: true })
-
-    // TODO: add swarm listen and add ourselves to the DHT
-
-    swarm.on('wire', function (wire) {
-      $('.connectedPeers span').text(swarm.wires.length)
-
-      // Send KEEP-ALIVE (every 60s) so peers will not disconnect the wire
-      wire.setKeepAlive(true)
-
-      // If peer supports DHT, send PORT message to report what port our DHT node
-      // is listening on
-      if (wire.peerExtensions.dht) {
-        // TODO: DHT doesn't support listening yet
-        // wire.port(dht.port)
-      }
-
-      // When peer sends PORT, add them to the routing table
-      wire.on('port', function (port) {
-        console.log('PORT', port)
-        // TODO: DHT doesn't have a routing table
-        // dht.add(wire.remoteAddress, port)
-      })
-
-      // Time to wait before considering requests timed out
-      wire.setTimeout(WIRE_TIMEOUT)
-
-      // Support extended messages:
-      // - ut_metadata (metadata fetching, trackerless torrents)
-      if (wire.peerExtensions) {
-        console.log('Wire ' + wire.remoteAddress + ' supports extended messages', wire.peerExtensions)
-        wire.extended(0, {
-          m: {
-            ut_metadata: 1
-          }
-          // TODO - this should be set once we have metadata
-          // metadata_size: xx
-        })
-      }
-
-      wire.on('extended', function (ext, buf) {
-        var dict
-        console.log('Received extended message ' + ext + ' from ' + wire.remoteAddress)
-
-        if (ext === 0) { // handshake
-
-          try {
-            console.log('decoding ' + buf.toString())
-            dict = bncode.decode(buf.toString())
-            console.log('got extended handshake: ' + JSON.stringify(dict))
-          } catch (e) {
-            console.error('Error decoding extended message: ' + e.message)
-          }
-
-          if (dict.m.ut_metadata && dict.metadata_size) {
-            var metadataSize = dict.metadata_size
-            var numPieces = Math.ceil(metadataSize / METADATA_BLOCK_SIZE)
-            console.log('metadata size: ' + metadataSize)
-            console.log(numPieces + ' pieces')
-
-            wire.metadata = new Buffer(metadataSize)
-
-            // request all pieces
-            for (var piece = 0; piece < numPieces; piece++) {
-              wire.extended(dict.m.ut_metadata, {
-                msg_type: 0,
-                piece: piece
-              })
-            }
-          }
-
-        } else if (ext === 1) { // ut_metadata
-
-          // 0 - request
-          // 1 - data
-          // 2 - reject
-
-          var str
-          var dataIndex
-          var data
-          try {
-            str = buf.toString()
-            console.log('decoding ' + str)
-            dataIndex = str.indexOf('ee') + 2
-            var msg = str.substring(0, dataIndex)
-            console.log('using ' + msg)
-            dict = bncode.decode(msg)
-            data = buf.slice(dataIndex)
-            console.log('got metadata: ' + JSON.stringify(dict))
-            console.log('got metadata data: ' + data.length + ' bytes')
-          } catch (e) {
-            console.error('Error decoding extended message: ' + e.message)
-          }
-
-          // {'msg_type': 1, 'piece': 0, 'total_size': 3425}
-          if (dict.msg_type === 1) { // data
-            console.log('total_size: ' + dict.total_size)
-            data.copy(wire.metadata, dict.piece * METADATA_BLOCK_SIZE)
-
-            var errorHandler = function (err) {
-              console.error('error' + err.toString())
-            }
-
-            chrome.fileSystem.chooseEntry({
-              type: 'saveFile',
-              suggestedName: displayName
-            }, function (writableFileEntry) {
-              writableFileEntry.createWriter(function (writer) {
-                writer.onerror = errorHandler
-                writer.onwriteend = function (e) {
-                  console.log('write complete')
-                }
-                writer.write(new Blob([wire.metadata]), { type: 'text/plain' })
-              }, errorHandler)
-            })
-          }
-        }
-      })
-
-    })
 
-    swarm.on('error', function (err) {
-      console.error(err.message)
-    })
+var manager = new TorrentManager()
 
-    // swarm.listen(r.dhtPort, function () {
-    //   console.log('Swarm listening on port ' + r.dhtPort)
-    // })
-  }]
-}, function (err) {
-  if (err) console.error(err.message)
-  else console.log('Setup complete')
-})
+manager.add('magnet:?xt=urn:btih:d2474e86c95b19b8bcfdb92bc12c9d44667cfa36&dn=Leaves+of+Grass+by+Walt+Whitman.epub')
 
+manager.on('error', function (err) {
+  console.error(err)
+  // TODO: Show error in UI somehow
+})
\ No newline at end of file
diff --git a/lib/Torrent.js b/lib/Torrent.js
new file mode 100644
index 0000000..cb1a5f9
--- /dev/null
+++ b/lib/Torrent.js
@@ -0,0 +1,179 @@
+module.exports = Torrent
+
+var bncode = require('bncode')
+var EventEmitter = require('events').EventEmitter
+var inherits = require('inherits')
+var magnet = require('magnet-uri')
+var Swarm = require('bittorrent-swarm')
+
+var METADATA_BLOCK_SIZE = 16 * 1024
+var WIRE_TIMEOUT = 10000
+
+inherits(Torrent, EventEmitter)
+
+function Torrent (uri, opts) {
+  if (!(this instanceof Torrent)) return new Torrent(uri, opts)
+  EventEmitter.call(this)
+
+  var info = this._parseMagnetUri(uri)
+  if (!info.infoHash)
+    throw new Error('invalid torrent uri')
+
+  this.infoHash = info.infoHash
+  this.displayName = info.displayName
+
+  this.swarm = new Swarm(this.infoHash, opts.peerId, { dht: true })
+
+  // TODO: swarm pooling should be smart about picking port
+  // this.swarm.listen(function (port) {
+  //   console.log('Swarm listening on port ' + port)
+  //   this.emit('listening', port)
+  // }.bind(this))
+
+  this.swarm.on('wire', function (wire) {
+    $('.connectedPeers span').text(this.swarm.wires.length)
+
+    // Send KEEP-ALIVE (every 60s) so peers will not disconnect the wire
+    wire.setKeepAlive(true)
+
+    // If peer supports DHT, send PORT message to report what port our DHT node
+    // is listening on
+    if (wire.peerExtensions.dht) {
+      console.log('peer supports DHT')
+      // TODO: DHT doesn't support listening yet
+      // wire.port(dht.port)
+    }
+
+    // When peer sends PORT, add them to the routing table
+    wire.on('port', function (port) {
+      console.log('received PORT: ', port)
+      // TODO: DHT doesn't have a routing table yet
+      // dht.add(wire.remoteAddress, port)
+    })
+
+    // Timeout for wire requests to this peer
+    wire.setTimeout(WIRE_TIMEOUT)
+
+    // Support extended messages:
+    // - ut_metadata (metadata fetching, trackerless torrents)
+    if (wire.peerExtensions) {
+      console.log('Wire ' + wire.remoteAddress + ' supports extended messages', wire.peerExtensions)
+      wire.extended(0, {
+        m: {
+          ut_metadata: 1
+        }
+        // TODO - this should be set once we have metadata
+        // metadata_size: xx
+      })
+    }
+
+    wire.on('extended', function (ext, buf) {
+      var dict
+      console.log('Received extended message ' + ext + ' from ' + wire.remoteAddress)
+
+      if (ext === 0) { // handshake
+
+        try {
+          console.log('decoding ' + buf.toString())
+          dict = bncode.decode(buf.toString())
+          console.log('got extended handshake: ' + JSON.stringify(dict))
+        } catch (e) {
+          console.error('Error decoding extended message: ' + e.message)
+        }
+
+        if (dict.m.ut_metadata && dict.metadata_size) {
+          var metadataSize = dict.metadata_size
+          var numPieces = Math.ceil(metadataSize / METADATA_BLOCK_SIZE)
+          console.log('metadata size: ' + metadataSize)
+          console.log(numPieces + ' pieces')
+
+          wire.metadata = new Buffer(metadataSize)
+
+          // request all pieces
+          for (var piece = 0; piece < numPieces; piece++) {
+            wire.extended(dict.m.ut_metadata, {
+              msg_type: 0,
+              piece: piece
+            })
+          }
+        }
+
+      } else if (ext === 1) { // ut_metadata
+
+        // 0 - request
+        // 1 - data
+        // 2 - reject
+
+        var str
+        var dataIndex
+        var data
+        try {
+          str = buf.toString()
+          console.log('decoding ' + str)
+          dataIndex = str.indexOf('ee') + 2
+          var msg = str.substring(0, dataIndex)
+          console.log('using ' + msg)
+          dict = bncode.decode(msg)
+          data = buf.slice(dataIndex)
+          console.log('got metadata: ' + JSON.stringify(dict))
+          console.log('got metadata data: ' + data.length + ' bytes')
+        } catch (e) {
+          console.error('Error decoding extended message: ' + e.message)
+        }
+
+        // {'msg_type': 1, 'piece': 0, 'total_size': 3425}
+        if (dict.msg_type === 1) { // data
+          console.log('total_size: ' + dict.total_size)
+          data.copy(wire.metadata, dict.piece * METADATA_BLOCK_SIZE)
+
+          var errorHandler = function (err) {
+            console.error('error' + err.toString())
+          }
+
+          chrome.fileSystem.chooseEntry({
+            type: 'saveFile',
+            suggestedName: this.displayName + '.torrent'
+          }, function (writableFileEntry) {
+            writableFileEntry.createWriter(function (writer) {
+              writer.onerror = errorHandler
+              writer.onwriteend = function (e) {
+                console.log('write complete')
+              }
+              writer.write(new Blob([wire.metadata]), { type: 'text/plain' })
+            }, errorHandler)
+          })
+        }
+      }
+    }.bind(this))
+
+  }.bind(this))
+
+  this.swarm.on('error', function (err) {
+    console.error(err.message)
+  })
+}
+
+/**
+ * Add a peer to the swarm
+ * @param {string} addr
+ */
+Torrent.prototype.addPeer = function (addr) {
+  this.swarm.add(addr)
+}
+
+//
+// HELPER METHODS
+//
+
+/**
+ * Given a magnet URI, return infoHash and displayName
+ * @param  {string} uri
+ * @return {Object}
+ */
+Torrent.prototype._parseMagnetUri = function (uri) {
+  var parsed = magnet(uri)
+  return {
+    displayName: parsed.dn,
+    infoHash: parsed.xt && parsed.xt.split('urn:btih:')[1]
+  }
+}
diff --git a/lib/TorrentManager.js b/lib/TorrentManager.js
new file mode 100644
index 0000000..bc9c4eb
--- /dev/null
+++ b/lib/TorrentManager.js
@@ -0,0 +1,63 @@
+module.exports = TorrentManager
+
+var $ = require('jquery')
+var DHT = require('bittorrent-dht')
+var EventEmitter = require('events').EventEmitter
+var hat = require('hat')
+var inherits = require('inherits')
+var Torrent = require('./Torrent')
+
+var MAX_PEERS = 200
+
+inherits(TorrentManager, EventEmitter)
+
+function TorrentManager () {
+  if (!(this instanceof TorrentManager)) return new TorrentManager()
+  EventEmitter.call(this)
+
+  // TODO: should these ids be consistent between restarts?
+  this.peerId = new Buffer('-WW0001-' + hat(48), 'utf8')
+  this.nodeId = new Buffer(hat(160), 'hex')
+
+  this.torrents = {}
+
+  this.dht = new DHT({ nodeId: this.nodeId })
+
+  this.dht.on('node', this.updateUI.bind(this))
+  this.dht.on('peer', this.updateUI.bind(this))
+
+  this.dht.on('peer', function (addr, infoHash) {
+    var torrent = this.torrents[infoHash]
+    torrent.addPeer(addr)
+  }.bind(this))
+
+  // this.dht.listen()
+
+}
+
+TorrentManager.prototype.add = function (uri) {
+  var torrent = new Torrent(uri, { peerId: this.peerId })
+  this.torrents[torrent.infoHash] = torrent
+
+  torrent.on('listening', function (port) {
+    // TODO: Add the torrent to the public DHT so peers know to find up
+  })
+
+  // TODO: DHT should support multiple infoHashes
+  this.dht.setInfoHash(torrent.infoHash)
+  this.dht.findPeers(MAX_PEERS) // TODO: should the DHT be concerned with max peers?
+
+  this.updateUI()
+}
+
+// TODO: show multiple torrents
+TorrentManager.prototype.updateUI = function () {
+  // console.log('Peer ID: ' + this.peerId.toString('utf8'))
+  // console.log('Node ID: ' + this.nodeId.toString('hex'))
+  $('.infoHash span').text(this.torrents['d2474e86c95b19b8bcfdb92bc12c9d44667cfa36'].infoHash)
+  $('.displayName span').text(this.torrents['d2474e86c95b19b8bcfdb92bc12c9d44667cfa36'].displayName)
+
+  $('.dhtNodes span').text(Object.keys(this.dht.nodes).length)
+  $('.dhtPeers span').text(Object.keys(this.dht.peers).length)
+}
+
diff --git a/package.json b/package.json
index 0fe2472..88770e8 100644
--- a/package.json
+++ b/package.json
@@ -22,17 +22,16 @@
     "url": "https://github.com/feross/webtorrent/issues"
   },
   "dependencies": {
-    "async": "~0.2.10",
     "bittorrent-dht": "0.x",
     "bittorrent-protocol": "0.x",
     "bittorrent-swarm": "0.x",
     "bncode": "~0.5.2",
     "browserify": "3.x",
     "browserify-shim": "~3.2.2",
-    "chrome-portfinder": "~0.2.2",
     "hat": "0.0.3",
+    "inherits": "~2.0.1",
     "jquery": "~2.1.0",
-    "magnet-uri": "0.x",
+    "magnet-uri": "1.x",
     "portfinder": "~0.2.1",
     "read-torrent": "~0.2.0",
     "speedometer": "~0.1.2"