From 72c4115c95947597c4de089d4ab616d2bb1539fc Mon Sep 17 00:00:00 2001
From: Dmitriy Ryajov <dryajov@gmail.com>
Date: Thu, 12 Sep 2019 15:54:12 -0600
Subject: [PATCH] wip: native libp2p chat sample

---
 examples/nativechat.nim | 153 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 153 insertions(+)
 create mode 100644 examples/nativechat.nim

diff --git a/examples/nativechat.nim b/examples/nativechat.nim
new file mode 100644
index 000000000..6d5b84bdc
--- /dev/null
+++ b/examples/nativechat.nim
@@ -0,0 +1,153 @@
+import tables, options, sequtils, algorithm, strformat, os, strutils
+import chronos, chronicles
+import ../libp2p/switch,
+       ../libp2p/multistream,
+       ../libp2p/crypto/crypto,
+       ../libp2p/protocols/identify,
+       ../libp2p/connection,
+       ../libp2p/transports/[transport, tcptransport],
+       ../libp2p/multiaddress,
+       ../libp2p/peerinfo,
+       ../libp2p/peer,
+       ../libp2p/protocols/protocol,
+       ../libp2p/protocols/secure/secure,
+       ../libp2p/protocols/secure/secio,
+       ../libp2p/protocols/pubsub/pubsub,
+       ../libp2p/protocols/pubsub/floodsub,
+       ../libp2p/muxers/muxer,
+       ../libp2p/muxers/mplex/mplex,
+       ../libp2p/muxers/mplex/types
+
+when not(compileOption("threads")):
+  {.fatal: "Please, compile this program with the --threads:on option!".}
+
+const ChatCodec = "/nim-libp2p/chat/1.0.0"
+type
+  CustomData = ref object
+    consoleFd: AsyncFD
+    serveFut: Future[void]
+
+  ChatProto = ref object of LPProtocol
+    customData*: CustomData
+    switch: Switch
+    transp: StreamTransport
+    isConnected: AsyncEvent
+    conn: Connection
+    client: bool
+    connected: bool
+
+# forward declaration
+proc readWriteLoop(p: ChatProto) {.async, gcsafe.}
+proc readAndPrint(p: ChatProto) {.async, gcsafe.} =
+  while true:
+    while p.connected:
+      echo cast[string](await p.conn.readLp())
+    await sleepAsync(100)
+
+proc dialPeer(p: ChatProto, address: string) {.async, gcsafe.} =
+  var parts = address.split("/")
+  if parts.len == 11 and parts[^2] != "ipfs" and parts[^2] != "p2p":
+    quit("invalid or incompelete peerId")
+
+  var remotePeer: PeerInfo
+  remotePeer.peerId = some(PeerID.init(parts[^1]))
+  remotePeer.addrs.add(MultiAddress.init(address))
+
+  echo &"dialing peer: {address}"
+  p.conn = await p.switch.dial(remotePeer, ChatCodec)
+  p.connected = true
+
+proc writeAndPrint(p: ChatProto) {.async, gcsafe.} = 
+  while true:
+    if p.connected:
+      echo "type your message:"
+    else:
+      echo "type an address or wait for a connection:"
+
+    var line = await p.transp.readLine()
+    if p.connected:
+      await p.conn.writeLp(line)
+    else:
+      try:
+        await p.dialPeer(line)
+      except:
+        echo &"unable to dial {line}"
+        echo getCurrentExceptionMsg()
+
+proc readWriteLoop(p: ChatProto) {.async, gcsafe.} =
+    asyncCheck p.writeAndPrint()
+    asyncCheck p.readAndPrint()
+
+method init(p: ChatProto) {.gcsafe.} =
+  proc handle(stream: Connection, proto: string) {.async, gcsafe.} = 
+    p.conn = stream
+    p.connected = true
+
+  p.codec = ChatCodec
+  p.handler = handle
+
+proc newChatProto(switch: Switch, transp: StreamTransport): ChatProto = 
+  new result
+  result.switch = switch
+  result.transp = transp
+  result.init()
+
+proc threadMain(wfd: AsyncFD) {.thread.} =
+  ## This procedure performs reading from `stdin` and sends data over
+  ## pipe to main thread.
+  var transp = fromPipe(wfd)
+ 
+  while true:
+    var line = stdin.readLine()
+    echo line
+    let res = waitFor transp.write(line & "\r\n")
+
+proc serveThread(customData: CustomData) {.async.} =
+  var transp = fromPipe(customData.consoleFd)
+
+  let seckey = PrivateKey.random(RSA)
+  var peerInfo: PeerInfo
+  peerInfo.peerId = some(PeerID.init(seckey))
+  var localAddress = "/ip4/127.0.0.1/tcp/55505"
+  echo "Type an address to bind to or Enter use the default /ip4/127.0.0.1/tcp/55505"
+  let a = await transp.readLine()
+  if a.len > 0:
+    localAddress = a
+ 
+  peerInfo.addrs.add(Multiaddress.init(localAddress))
+  proc createMplex(conn: Connection): Muxer =
+    result = newMplex(conn)
+
+  var mplexProvider = newMuxerProvider(createMplex, MplexCodec)
+  var transports = @[Transport(newTransport(TcpTransport))]
+  var muxers = [(MplexCodec, mplexProvider)].toTable()
+  var identify = newIdentify(peerInfo)
+  # var secureManagers = @[Secure(newSecIo(seckey.getKey()))]
+  var switch = newSwitch(peerInfo, transports, identify, muxers)
+
+  var libp2pFuts = await switch.start()
+  var chatProto = newChatProto(switch, transp)
+  switch.mount(chatProto)
+  echo "PeerID: " & peerInfo.peerId.get().pretty
+  echo "listening on: "
+  for a in switch.peerInfo.addrs:
+    echo a
+
+  await chatProto.readWriteLoop()
+  await allFutures(libp2pFuts)
+
+proc main() {.async.} =
+  var data = new CustomData
+
+  var (rfd, wfd) = createAsyncPipe()
+  if rfd == asyncInvalidPipe or wfd == asyncInvalidPipe:
+    raise newException(ValueError, "Could not initialize pipe!")
+  
+  data.consoleFd = rfd
+  data.serveFut = serveThread(data)
+  var thread: Thread[AsyncFD]
+  thread.createThread(threadMain, wfd)
+  await data.serveFut
+
+when isMainModule:
+  waitFor(main())