# Group Messaging　(Different DHT)
###### tags: `Kizuna-architecture`

#### comments
- how to add/remove groups in different DHT
- TODO: sync/async invites flow
- TODO: workflow for when cloneDNA is not successful
- Since it's a separate DNA, is it safe to store messages in DHT

### GroupMessageEntry

// private entry commited in source chain
pub struct Invite {
    group_uui: String,
    initial_members: Vec<AgentPubKey>,
    timestamp: Timestamp
}
pub struct Groups {
    group_uuids: Vec<String>,
    blocked: Vec<String>
}

pub struct MessageEntry {
    author: AgentPubKey,
    receiver: Vec<AgentPubKey>,
    group_uuid: String,
    payload: String,
    time_sent: Timestamp,
    time_received: Option<Timestamp>
}

sequenceDiagram
    participant AUI as Alice_UI
    participant ALD as Alice_Lobby_DNA
    participant AC as Alice_Conductor
    participant BUI as Bobby_UI
    participant BLD as Bobby_Lobby_DNA
    participant CUI as Charlie_UI
    participant CLD as Charlie_Lobby_DNA
    participant LDHT as Lobby_DHT
    participant GDHT as Group_DHT
    
    ALD-->>AUI: fetch Groups entry
    BLD-->>BUI: fetch Groups entry
    CLD-->>CUI: fetch Groups entry
    
    AUI-->>AUI: choose participants in GC
    AUI-->>ALD: send usernames/agent pubkeys
    par alit to bob
    ALD-->>BLD: send invite
    and alice to clarice
    ALD-->>CLD: send invite
    end
    
    AC-->>AC: create the new group DNA from tempalte
    alt success
    AC-->>AUI: cloneDNA successful
    else fail
    note left of AC: TODO  
    end
    
    alt attempt synchronous messaging
        par sending to Bobby
            
            ALD-->>BLD: call_remote! receive_group_message
            BLD-->>BLD: check the group_id
            alt group is blocked
                BLD-->>BLD: do nothing
            else group is not blocked
                BLD-->>BLD: check the receivers
                alt someone is blocked in group
                    BLD-->>BUI: emit_signal the message along with warning that someone in group is blocked  
                else no one is blocked
                    BLD-->>BUI: emit_signal the message 
                end 
            end
            BUI-->>BUI: check whether it's the first message of the group by filtering against Groups entry
            alt first time
                BUI-->>BUI: show the accept, delete, block banner
            end
        and sending to Charlie
            note right of BUI: Same with Alice </br> to Bobby
        end
        ALD-->>AUI: return success
    else switch to asynchronous messaging for offline contacts
        ALD-->>LDHT: commit message in DHT
        LDHT-->>ALD: return message address
        ALD-->>LDHT: link message to Bobby's GroupChats entry
        LDHT-->>ALD: return success
        ALD-->>AUI: return success        
    end