better chat list view + anchor to bottom. sqlite db for chats + LIFO-ordered

Plugins/ZShell/Llm/llmclient.hpp

@@ -0,0 +1,103 @@
+#pragma once
+
+#include <QByteArray>
+#include <QNetworkAccessManager>
+#include <QObject>
+#include <QPointer>
+#include <QString>
+#include <QStringList>
+#include <functional>
+
+class QJsonObject;
+class QNetworkReply;
+
+namespace ZShell::llm {
+
+class ChatGeneration;
+class ChatSession;
+
+// The only component that talks to the LLM server: owns the network
+// manager, the in-flight streaming state and the SSE parsing.
+class LlmClient : public QObject {
+	Q_OBJECT
+
+	public:
+	explicit LlmClient(QObject* parent = nullptr);
+	~LlmClient() override;
+
+	[[nodiscard]] QString endpoint() const { return m_endpoint; }
+	[[nodiscard]] QString model() const { return m_model; }
+	[[nodiscard]] double temperature() const { return m_temperature; }
+	[[nodiscard]] QStringList availableModels() const {
+		return m_availableModels;
+	}
+	[[nodiscard]] int contextSize() const { return m_contextSize; }
+	void setEndpoint(const QString& value);
+	void setModel(const QString& value);
+	void setTemperature(double value);
+	void setContextSize(int size);
+	void probeContextSize();
+
+	[[nodiscard]] bool busy() const { return m_busy; }
+	[[nodiscard]] QString streamingChatId() const { return m_streamingChatId; }
+	[[nodiscard]] ChatSession* streamingSession() const { return m_active; }
+
+	// Streams a new assistant reply into `target` (the active generation of
+	// a message of `session`). The context sent to the model is every
+	// message of the session that is older than the target message.
+	void startGeneration(ChatSession* session, ChatGeneration* target);
+	void stop();
+	void endStream();
+	// Clears the session's conversation once the current stream ends.
+	void clearOnFinish(ChatSession* session);
+	// A session is about to be destroyed; drop any state pointing at it.
+	void sessionRemoved(ChatSession* session);
+
+	void refreshModels();
+	void requestTitle(ChatSession* session, const QString& userText);
+	void requestIcon(ChatSession* session, const QString& userText);
+
+	Q_SIGNALS:
+	void busyChanged();
+	void endpointChanged();
+	void modelChanged();
+	void availableModelsChanged();
+	void contextSizeChanged();
+	void streamingChatIdChanged();
+	void errorOccurred(const QString& message);
+	void titleSuggested(ZShell::llm::ChatSession* session, const QString& title);
+	void iconSuggested(ZShell::llm::ChatSession* session, const QString& icon);
+
+	private:
+	void finalize();
+	void fail(const QString& message);
+	void handleLine(const QByteArray& line);
+	void drainBuffer();
+	void updateTokenUsage(const QJsonObject& data);
+	void setBusy(bool value);
+	void setStreamingChatId(const QString& id);
+	void shortRequest(
+		const QString& tag,
+		const QString& systemPrompt,
+		const QString& userText,
+		std::function<void(QString result)> onResult);
+	static QString completionsPath(const QString& endpoint, const QString& subpath);
+	static QString serverErrorMessage(
+		const QByteArray& body, const QString& fallback);
+
+	QNetworkAccessManager m_manager;
+	QNetworkReply* m_reply = nullptr;
+	QByteArray m_buffer;
+	ChatSession* m_active = nullptr;
+	ChatGeneration* m_streaming = nullptr;
+	QPointer<ChatSession> m_pendingClear;
+	bool m_busy = false;
+	QString m_streamingChatId;
+	QString m_endpoint;
+	QString m_model;
+	QStringList m_availableModels;
+	double m_temperature = 0.7;
+	int m_contextSize = 0;
+};
+
+} // namespace ZShell::llm