#include "ChatRoom.h"
#include "WebSocketChatSession.h"

void ChatRoom::join(WebSocketSession *session) {
    std::lock_guard<std::mutex> lock(m_mutex);
    m_sessions.insert(session);
}

void ChatRoom::leave(WebSocketSession *session) {
    std::lock_guard<std::mutex> lock(m_mutex);
    m_sessions.erase(session);
}

void ChatRoom::send(std::string message) {
    auto const ss = std::make_shared<std::string const>(std::move(message));

    // Make a local list of all the weak pointers representing
    // the sessions, so we can do the actual sending without
    // holding the mutex:
    std::vector<std::weak_ptr<WebSocketSession>> v;
    {
        std::lock_guard<std::mutex> lock(m_mutex);
        v.reserve(m_sessions.size());
        for (auto p : m_sessions) v.emplace_back(p->weak_from_this());
    }

    // For each session in our local list, try to acquire a strong
    // pointer. If successful, then send the message on that session.
    for (auto const &wp : v)
        if (auto sp = wp.lock()) sp->send(ss);
}