omikron/src/calls/call_manager.rs

use dashmap::DashMap;
use once_cell::sync::Lazy;
use std::sync::Arc;
use uuid::Uuid;

use crate::calls::{
    call_group::{CallGroup, CallSecretEnvelope},
    call_util,
    caller::Caller,
};

pub static CALL_GROUPS: Lazy<DashMap<Uuid, Arc<CallGroup>>> = Lazy::new(|| DashMap::new());
#[allow(dead_code)]
pub async fn get_call_invites(user_id: u64) -> Vec<Arc<Caller>> {
    let mut callers = Vec::new();
    for (_, cg) in CALL_GROUPS.clone().into_iter() {
        let members = cg.members.read().await;
        for member in members.iter() {
            if member.user_id == user_id {
                callers.push(member.clone());
            }
        }
    }
    callers
}

pub async fn get_call(call_id: Uuid) -> Option<Arc<CallGroup>> {
    if let Some(b) = CALL_GROUPS.get(&call_id) {
        Some(b.clone())
    } else {
        None
    }
}

pub async fn get_call_groups(user_id: u64) -> Vec<Arc<CallGroup>> {
    let mut call_groups = Vec::new();
    for (_, cg) in CALL_GROUPS.clone().into_iter() {
        let is_member = {
            let members = cg.members.read().await;
            members.iter().any(|m| m.user_id == user_id)
        };

        if is_member {
            call_groups.push(cg.clone());
        }
    }
    call_groups
}

pub async fn get_call_token(user_id: u64, call_id: Uuid) -> Option<String> {
    if let Some(cg) = CALL_GROUPS.get(&call_id) {
        let mut members = cg.members.write().await;

        if let Some(member) = members.iter().find(|m| m.user_id == user_id) {
            return Some(member.create_token());
        }

        let new_caller = Arc::new(Caller::new(user_id, call_id, false));
        let token = new_caller.create_token();

        members.push(new_caller);

        return Some(token);
    }

    let caller = Arc::new(Caller::new(user_id, call_id, true));
    let call_group = Arc::new(CallGroup::new(call_id, caller.clone()));

    CALL_GROUPS.insert(call_id, call_group.clone());

    let _ = call_util::create_room(call_id).await;
    call_group.update_admins().await;

    Some(caller.create_token())
}

pub async fn add_invite(
    call_id: Uuid,
    inviter_id: u64,
    invitee_id: u64,
    secret: CallSecretEnvelope,
) -> bool {
    if let Some(cg) = CALL_GROUPS.get(&call_id) {
        let mut members = cg.members.write().await;

        let is_inviter_member = members.iter().any(|m| m.user_id == inviter_id);

        if is_inviter_member {
            if !members.iter().any(|m| m.user_id == invitee_id) {
                members.push(Arc::new(Caller::new(invitee_id, call_id, false)));
            }

            let mut secrets = cg.secrets.write().await;
            secrets.insert(invitee_id, secret);

            return true;
        }
    }
    false
}

pub fn should_forward_invite(inviter_id: u64, invitee_id: u64) -> bool {
    inviter_id != invitee_id
}

#[cfg(test)]
mod tests {
    use super::*;

    fn envelope(label: &str) -> CallSecretEnvelope {
        CallSecretEnvelope {
            secret_id: format!("call:test:{label}"),
            version_number: 1,
            encrypted_secret: format!("encrypted:{label}").into_bytes(),
            kem_ciphertext: format!("kem:{label}").into_bytes(),
            wrapping_scheme: "mtp-call-secret-kem-chacha20poly1305-hkdf-sha256-v1".to_string(),
        }
    }

    #[tokio::test]
    async fn add_invite_stores_receiver_envelope_only_under_receiver_id() {
        let call_id = Uuid::new_v4();
        let sender_id = 11;
        let receiver_id = 22;
        let group = Arc::new(CallGroup::new(
            call_id,
            Arc::new(Caller::new(sender_id, call_id, true)),
        ));
        CALL_GROUPS.insert(call_id, group.clone());

        let receiver_secret = envelope("receiver");

        assert!(add_invite(call_id, sender_id, receiver_id, receiver_secret.clone(),).await);

        assert_eq!(
            group.get_secret_for_user(receiver_id).await,
            Some(receiver_secret.clone())
        );
        assert_eq!(group.get_secret_for_user(sender_id).await, None);

        CALL_GROUPS.remove(&call_id);
    }

    #[tokio::test]
    async fn self_invite_stores_secret_without_duplicating_member() {
        let call_id = Uuid::new_v4();
        let sender_id = 33;
        let group = Arc::new(CallGroup::new(
            call_id,
            Arc::new(Caller::new(sender_id, call_id, true)),
        ));
        CALL_GROUPS.insert(call_id, group.clone());

        let secret = envelope("self");

        assert!(add_invite(call_id, sender_id, sender_id, secret.clone()).await);

        assert_eq!(group.get_secret_for_user(sender_id).await, Some(secret));
        assert_eq!(
            group
                .members
                .read()
                .await
                .iter()
                .filter(|member| member.user_id == sender_id)
                .count(),
            1
        );

        CALL_GROUPS.remove(&call_id);
    }

    #[test]
    fn self_invites_are_not_forwarded() {
        assert!(!should_forward_invite(44, 44));
        assert!(should_forward_invite(44, 55));
    }
}