feat: Add session layout

sources/Session/SystemPromptBuilder.cpp

@@ -0,0 +1,71 @@
+// Copyright (C) 2024-2026 Petr Mironychev
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "SystemPromptBuilder.hpp"
+
+namespace QodeAssist {
+
+SystemPromptBuilder::SystemPromptBuilder(QObject *parent)
+    : QObject(parent)
+{}
+
+void SystemPromptBuilder::setLayer(const QString &name, const QString &text)
+{
+    for (auto &pair : m_layers) {
+        if (pair.first == name) {
+            if (pair.second == text) return;
+            pair.second = text;
+            emit layersChanged();
+            return;
+        }
+    }
+    m_layers.append({name, text});
+    emit layersChanged();
+}
+
+void SystemPromptBuilder::clearLayer(const QString &name)
+{
+    for (auto it = m_layers.begin(); it != m_layers.end(); ++it) {
+        if (it->first == name) {
+            m_layers.erase(it);
+            emit layersChanged();
+            return;
+        }
+    }
+}
+
+void SystemPromptBuilder::clear()
+{
+    if (m_layers.isEmpty()) return;
+    m_layers.clear();
+    emit layersChanged();
+}
+
+QString SystemPromptBuilder::layer(const QString &name) const
+{
+    for (const auto &pair : m_layers) {
+        if (pair.first == name) return pair.second;
+    }
+    return {};
+}
+
+QStringList SystemPromptBuilder::layerNames() const
+{
+    QStringList out;
+    out.reserve(m_layers.size());
+    for (const auto &pair : m_layers) out.append(pair.first);
+    return out;
+}
+
+QString SystemPromptBuilder::compose(const QString &separator) const
+{
+    QStringList parts;
+    parts.reserve(m_layers.size());
+    for (const auto &pair : m_layers) {
+        if (!pair.second.isEmpty())
+            parts.append(pair.second);
+    }
+    return parts.join(separator);
+}
+
+} // namespace QodeAssist