pwweb/src/graph_engine.h

#pragma once

#include "graph_types.h"
#include <functional>
#include <mutex>
#include <vector>
#include <unordered_map>
#include <thread>
#include <atomic>

#include <pipewire/utils.h>     // pw_thread_loop, etc.
#include <spa/utils/list.h>     // spa_list
#include <spa/utils/hook.h>     // spa_hook

struct pw_thread_loop;
struct pw_context;
struct pw_core;
struct pw_registry;

namespace pwgraph {

class GraphEngine {
public:
    using ChangeCallback = std::function<void()>;

    GraphEngine();
    ~GraphEngine();

    bool open();
    void close();

    // Set callback invoked when graph changes
    void setOnChange(ChangeCallback cb);

    // Thread-safe snapshot of the current graph state
    struct Snapshot {
        std::vector<Node> nodes;
        std::vector<Port> ports;
        std::vector<Link> links;
    };
    Snapshot snapshot() const;

    // Connect/disconnect two ports (thread-safe, blocks until done)
    bool connectPorts(uint32_t output_port_id, uint32_t input_port_id);
    bool disconnectPorts(uint32_t output_port_id, uint32_t input_port_id);

    // Volume control
    bool setNodeVolume(uint32_t node_id, float volume);
    bool setNodeMute(uint32_t node_id, bool mute);

    // Module loading (virtual devices)
    uint32_t loadModule(const char *name, const char *args);
    bool unloadModule(uint32_t module_id);

    // PipeWire internal data (exposed for C callbacks)
    struct PwData {
        pw_thread_loop *loop;
        pw_context      *context;
        pw_core         *core;
        spa_hook         core_listener;
        pw_registry     *registry;
        spa_hook         registry_listener;
        int              pending_seq;
        spa_list         pending;   // doubly-linked list head for pending syncs
        int              last_seq;
        int              last_res;
        bool             error;
    };

    PwData& pwData() { return m_pw; }

    // Object management (called from C callbacks)
    struct Object {
        enum Type { ObjNode, ObjPort, ObjLink };
        uint32_t     id;
        Type         type;
        void        *proxy;
        void        *info;
        void       (*destroy_info)(void*);
        spa_hook     proxy_listener;
        spa_hook     object_listener;
        int          pending_seq;
        spa_list     pending_link;
        GraphEngine *engine_ref;  // back-pointer set in create_proxy_for_object

        Object(uint32_t id, Type type);
        virtual ~Object();
    };

    struct NodeObj : Object {
        NodeObj(uint32_t id) : Object(id, ObjNode) {}
        Node node;
    };

    struct PortObj : Object {
        PortObj(uint32_t id) : Object(id, ObjPort) {}
        Port port;
    };

    struct LinkObj : Object {
        LinkObj(uint32_t id) : Object(id, ObjLink) {}
        Link link;
    };

    void    addObject(uint32_t id, Object *obj);
    Object *findObject(uint32_t id) const;
    void    removeObject(uint32_t id);
    void    clearObjects();

    NodeObj *findNode(uint32_t node_id) const;
    PortObj *findPort(uint32_t port_id) const;
    LinkObj *findLink(uint32_t link_id) const;

    void notifyChanged();

private:
    PwData m_pw;

    mutable std::mutex m_mutex;  // protects m_objects and graph data
    std::unordered_map<uint32_t, Object*> m_objects_by_id;
    std::vector<Object*> m_objects;

    ChangeCallback m_on_change;
    std::atomic<bool> m_running;

    // Port type hashes
    uint32_t m_audio_type;
    uint32_t m_midi_type;
    uint32_t m_midi2_type;
    uint32_t m_video_type;
    uint32_t m_other_type;

public:
    uint32_t audioPortType() const { return m_audio_type; }
    uint32_t midiPortType()  const { return m_midi_type; }
    uint32_t videoPortType() const { return m_video_type; }
    uint32_t otherPortType() const { return m_other_type; }
};

} // namespace pwgraph