feat: Add session layout

sources/Session/SessionManager.cpp

@@ -0,0 +1,105 @@
+// Copyright (C) 2024-2026 Petr Mironychev
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "SessionManager.hpp"
+
+#include "Agent.hpp"
+#include "AgentFactory.hpp"
+#include "Session.hpp"
+
+namespace QodeAssist {
+
+SessionManager::SessionManager(QObject *parent)
+    : QObject(parent)
+{}
+
+SessionManager::SessionManager(AgentFactory *agentFactory, QObject *parent)
+    : QObject(parent)
+    , m_agentFactory(agentFactory)
+{}
+
+SessionManager::~SessionManager() = default;
+
+Session *SessionManager::createSession()
+{
+    auto *session = new Session(this);
+    m_sessions.append(session);
+    emit sessionCreated(session);
+    return session;
+}
+
+Session *SessionManager::createSession(const QString &agentName, QString *errorOut)
+{
+    return createSession(agentName, /*externalHistory=*/nullptr, errorOut);
+}
+
+Session *SessionManager::createSession(
+    const QString &agentName, ConversationHistory *externalHistory, QString *errorOut)
+{
+    if (!m_agentFactory) {
+        if (errorOut)
+            *errorOut = QStringLiteral("SessionManager: no AgentFactory bound");
+        return nullptr;
+    }
+
+    QString agentErr;
+    Agent *agent = m_agentFactory->create(agentName, /*parent=*/nullptr, &agentErr);
+    if (!agent) {
+        if (errorOut)
+            *errorOut = agentErr.isEmpty()
+                            ? QStringLiteral("SessionManager: agent '%1' not found").arg(agentName)
+                            : agentErr;
+        return nullptr;
+    }
+
+    auto *session = new Session(agent, externalHistory, this);
+    if (!session->isValid()) {
+        if (errorOut)
+            *errorOut = session->invalidReason();
+        delete session; // also deletes the reparented agent
+        return nullptr;
+    }
+
+    m_sessions.append(session);
+    emit sessionCreated(session);
+    return session;
+}
+
+void SessionManager::removeSession(Session *session)
+{
+    if (!session)
+        return;
+
+    const int idx = m_sessions.indexOf(session);
+    if (idx < 0)
+        return;
+
+    if (session->isInFlight())
+        session->cancel();
+
+    m_sessions.removeAt(idx);
+    emit sessionRemoved(session);
+    session->deleteLater();
+}
+
+QList<Session *> SessionManager::sessions() const
+{
+    QList<Session *> out;
+    out.reserve(m_sessions.size());
+    for (const auto &p : m_sessions) {
+        if (p)
+            out.append(p.data());
+    }
+    return out;
+}
+
+void SessionManager::cancelAll()
+{
+    const auto snapshot = m_sessions;
+    for (const auto &p : snapshot) {
+        if (p && p->isInFlight())
+            p->cancel();
+    }
+}
+
+} // namespace QodeAssist