From 4cd6faec69167ef46e73b909e3d234d2f9cd1d28 Mon Sep 17 00:00:00 2001
From: Rekai Musuka <musukarekai@gmail.com>
Date: Wed, 5 Sep 2018 17:19:21 +0100
Subject: [PATCH] File Transfer Code kinda completed :/

---
 app/javascript/packs/file_transfer.js | 122 ++++++++++++++++++++++++++
 app/javascript/packs/webrtc.js        |   3 +
 2 files changed, 125 insertions(+)
 create mode 100644 app/javascript/packs/file_transfer.js

diff --git a/app/javascript/packs/file_transfer.js b/app/javascript/packs/file_transfer.js
new file mode 100644
index 0000000..37f782b
--- /dev/null
+++ b/app/javascript/packs/file_transfer.js
@@ -0,0 +1,122 @@
+export default class FileTransfer {
+  constructor() {
+    this.local = document.querySelector("#remote-video-container #local-video");
+    this.remote = document.querySelector(`#remote-video-container>video`);
+    this.sendChannel = null;
+    this.recieveChannel = null;
+    this.files = null;
+
+    this.recieveBuffer = [];
+    this.recievedSize = 0;
+
+
+    this.listen();
+  }
+
+  listen() {
+    this.remote.addEventListener('dragover', (e) => {
+      e.preventDefault();
+    })
+    this.remote.addEventListener('drop', (e) => {
+      e.preventDefault();
+      this.files = e.dataTransfer.files;
+
+      fetch("chat_room_sessions", {
+          method: "POST",
+          body: JSON.stringify({
+            type: "FILE_METADATA",
+            size: this.files[0].size,
+            name: this.files[0].name
+          }),
+          headers: { "content-type": "application/json", "X-CSRF-Token": document.querySelector('meta[name=csrf-token]').content }
+        });
+    }, false);
+  }
+
+  addPeer(connection) {
+    this.sendChannel = connection.createDataChannel('sendDataChannel');
+    this.sendChannel.binaryType = 'arraybuffer';
+    console.log("Created Send Channel.");
+
+    this.sendChannel.addEventListener('open', this.onSendOpen);
+    this.sendChannel.addEventListener('close', this.onSendClose);
+    this.sendChannel.addEventListener('error', this.onSendError);
+
+    connection.addEventListener('datachannel', this.onRecieveChannel);
+  }
+
+  onSendOpen() {
+    const state = this.sendChannel.readyState;
+    if (state === "open") this.send();
+  }
+
+  onSendClose() {
+    console.log("Send Channel is Closed.");
+  }
+
+  send() {
+    const file = this.files[0];
+    console.log("Sending File: " + file.name);
+
+    if (file.size === 0) {
+      throw new Error("0 is an invalid size...");
+    }
+
+    const chunkSize = 16384; //Why is this?
+    const reader = new FileReader();
+    let offset = 0;
+
+    reader.addEventListener('error', console.error);
+    reader.addEventListener('abort', console.info);
+    reader.addEventListener('load', (e) => {
+      console.log("Loading File...", e);
+      this.sendChannel.send(e.target.result);
+      offset += e.target.result.byteLength;
+
+      if (offset < file.size) readSlice(offset);
+    });
+
+    const readSlice = offset => {
+      reader.readAsArrayBuffer(file.slice(offset, offset + chunkSize));
+    }
+    readSlice(0);
+  }
+
+  end() {
+    this.sendChannel.close();
+    if (this.recieveChannel) this.recieveChannel.close();
+  }
+
+  onRecieveChannel(e) {
+    this.recieveChannel = e.channel;
+    this.recieveChannel.binaryType = 'arraybuffer';
+    this.recieveChannel.onmessage = this.onMessageRecieve;
+    this.recieveChannel.onopen = this.onOpenRecieve;
+    this.recieveChannel.onclose = this.onCloseRecieve;
+  }
+
+  onOpenRecieve() {
+    console.log("Recieve Channel is Open");
+  }
+
+  onCloseRecieve() {
+    console.log("Recieve Channel is Closed.");
+  }
+
+  onMessageRecieve(e) {
+    this.recieveBuffer.push(e.data);
+    this.recievedSize += e.data.byteLength;
+
+    //File Size needs to be recieved from ActionCable
+    if (this.recievedSize === file.size) {
+      const recieved = new Blob(this.recieveBuffer);
+      this.recieveBuffer = [];
+
+
+      const url = URL.createObjectURL(recieved);
+      //Get File Name Through ActionCable
+
+      this.end();
+    }
+  }
+}
diff --git a/app/javascript/packs/webrtc.js b/app/javascript/packs/webrtc.js
index fd787df..4507751 100644
--- a/app/javascript/packs/webrtc.js
+++ b/app/javascript/packs/webrtc.js
@@ -1,4 +1,5 @@
 // Broadcast Types
+import FileTransfer from './file_transfer';
 
 const JOIN_ROOM = "JOIN_ROOM";
 const EXCHANGE = "EXCHANGE";
@@ -12,11 +13,13 @@ let remoteVideoContainer;
 // Objects
 let pcPeers = {}; // peer connection
 let localstream;
+let ft;
 
 window.onload = () => {
   currentUser = document.getElementById("current-user").innerHTML;
   localVideo = document.getElementById("local-video");
   remoteVideoContainer = document.getElementById("remote-video-container");
+  ft = new FileTransfer();
 };
 
 // Ice Credentials