Firebase Chat.md

archiving will be handled in server, so no push to offline necessary. This will make client more light.

NOTE always set ts to current time when you push or set the data.

##Chat Apps with Firebase :

To create a chat, necessary firebase components :

####USER

User url location is used to monitor online/offline status of users :

var userListRef = new Firebase('https://test-app.firebaseio.com/users');

#####Online When user online, push into the userListRef

  {
    id: "187154", 
    code_id: "TSDQWERY", 
    name: "Jhon", 
    gender : "Male",
    filename_thumb : "thumb_68304308153044aad82a33.jpg"
    on: 'connect' ,
    status: "online", 
    ts: 1399880861, 
  }

ts is current timestamp in epoch format when user online

#####Idle when user is idle (there is no activity in chat after 5 minutes, can be detected by timing the last time user tap, click or type something in screen), set current user ref into

  {
    id: "187154", 
    code_id: "TSDQWERY", 
    name: "Jhon", 
    gender : "Male",
    filename_thumb : "thumb_68304308153044aad82a33.jpg",
    on: 'connect' ,
    status: "idle", 
    ts: 1399880861
  }

ts is current timestamp in epoch format when user idle

#####Away User is away if no activity in chat after 5 minutes from status idle, can be detected by timing the last time user tap, click or type something in screen, set current user ref into

  {
    id: "187154", 
    code_id: "TSDQWERY", 
    name: "Jhon", 
    gender : "Male",
    filename_thumb : "thumb_68304308153044aad82a33.jpg",
    on: 'connect' ,
    status: "away", 
    ts: 1399880861
  }

ts is current timestamp in epoch format when user away

#####Offline When app closed, tab closed (on browser) or refresh page. update userListRef on: "disconnect" but user status still status : "online"

 {
    id: "187154", 
    code_id: "TSDQWERY", 
    name: "Jhon", 
    gender : "Male",
    filename_thumb : "thumb_68304308153044aad82a33.jpg",
    on: 'disconnect',
    status: "online", 
    ts: 1399880861
  }

For 10 second if user on:"disconnect" not back online then update userListRef status: "offline"

  {
    id: "187154", 
    code_id: "TSDQWERY", 
    name: "Jhon", 
    gender : "Male",
    filename_thumb : "thumb_68304308153044aad82a33.jpg",
    on: 'disconnect',
    status: "offline", 
    ts: 1399880861
  }

#####Listing to Firebase event

Application only need to listen to userListRef events.

When child_added event received, add user to online list.
When child_removed event received, remove user from online user and update his status to offline.
When child_update event received, update user status to idle or online.

####CHANNEL

var userChannelListRef = new Firebase('https://test-app.firebaseio.com/channel');

Channel url is used to monitor who want to talk to specific user-id from another-user-id. Each user will have his/her own channel url. Data in channel is used to connect origin and destination in one chat ref

For example, lets say we have two users with id : John and Jane. John wants to chat to Jane.

When John click Jane chat button, we need create and push two reference :

var jhonChannelRef = new Firebase('https://test-app.firebaseio.com/channel/John/Jane');
var janeChannelRef = new Firebase('https://test-app.firebaseio.com/channel/Jane/Jhon');

Push to jhonChannelRef :

  {
  	box_chat: "open"
    to: "Jane",
    ts: 1396838766
  }

And push to janeChannelRef :

  {
    box_chat: "ready"
    from: "Jhon",
    ts: 1396838766
  }

#####box_chat Specific box_chat property used for indicator chatbox on web with any position :

box_chat :"ready" that means channel has create but chat box not yet open.
box_chat :"open" that means chat box open position so wherever the web page chat box still open.
box_chat :"close" that means chat box has close position.

####CHAT

Chat reference always formed by Channel reference, in case :

When John want to talk with Jane, The firebase ref would be:

var chatRef = new Firebase('https://test-app.firebaseio.com/chat/John-Jane);

We need to sort the string of the username involved, so it would be in correct order.

var part = ['John','Jane'].sort();
var chatRef = new Firebase('https://test-app.firebaseio.com/chat/'+ part[0] +'-' + part[1]);

Even though Jane wants talk to Jhon keep using the same reference chatRef that is always connected

for example Jhon Want to Chat with Jane :

var chatRef = new Firebase('https://test-app.firebaseio.com/chat/Jhon-Jane)'

then push data to chatRef :

  {
  	filename_thumb: "thumb_68304308153044aad82a33.jpg",
  	from: "Jhon",
  	to: "Jane",
  	message: "Hi !",
  	status: "read",
  	ts: 1396838766
  }

and when Jane want to chat with Jhon, then push with same reference chatRef :

  {
  	filename_thumb: "thumb_68304308153044aad82a33.jpg",
  	from: "Jane",
  	to: "Jhon",
  	message: "yeah, how u doing ?",
  	status: "read",
  	ts: 1396838766
  }

On process chating, if Jhon send or push chat message to Jane we have to change channel Reference : from -> to || to -> from

example : Jhon chat to Jane, push this reference :

var ref = new Firebase('https://test-app.firebaseio.com/channel/John/Jane');

following data :

  {
    box_chat: "open"
    to: "Jane",
    ts: 1396838766
  }

and if Jane chat with Jhon, push this reference :

var ref = new Firebase('https://test-app.firebaseio.com/channel/Jane/Jhon');

following data :

  {
    box_chat: "open"
    from: "Jane",
    ts: 1396838766
  }

and continues like that, so we can use channel reference to take the last conversation from & to

khalifah86/Firebase Chat.md