#pragma once

#include "fgc/CameraProfile.h"
#include "fgc/RawImage.h"
#include "fgc/SettleRule.h"

#include <cstdint>
#include <functional>
#include <string>
#include <vector>

namespace fgc {

// One captured frame, owning a copy of its pixel buffer (was image_store_8bit).
struct Frame {
    std::vector<uint8_t> data;   // as delivered: BayerRG12p stays packed
    uint32_t  width  = 0;
    uint32_t  height = 0;
    int       channels = 0;     // values per pixel as delivered: 3 (RGB) or 1 (mono, Bayer mosaic)
    // How `data` is laid out. Unknown only for a format the program does not
    // handle; `channels` then says what it holds, as before layouts existed.
    PixelLayout layout = PixelLayout::Unknown;
    long long timestamp_ms = 0; // Unix epoch ms
    int       cam_id = 0;       // index into the configured camera list

    // What the camera says it exposed this frame with (its per-frame chunk
    // data). Negative when the profile does not turn chunk data on.
    double exposure_us = -1.0;
    double gain_db     = -1.0;
    double wb_red      = -1.0;  // BalanceRatio, red against green
    double wb_blue     = -1.0;
    // Sampled from `data` on arrival (see RawImage.h); invalid when the layout
    // is Unknown.
    BrightnessSample brightness;
};

// Live per-camera identity, sensor telemetry, and acquisition stats, for the
// expanded camera view. Populated by deviceInfo(); fields the source can't read
// are left at their defaults.
struct CameraDeviceInfo {
    std::string id;
    std::string model;
    std::string serial;
    bool        streaming = false;

    // Current frame geometry as delivered.
    uint32_t  width         = 0;
    uint32_t  height        = 0;
    long long payload_bytes = 0;

    // Live sensor telemetry (read from the camera, throttled).
    double exposure_us    = 0.0;
    double gain_db        = 0.0;
    double temperature_c  = 0.0;
    double actual_fps     = 0.0;

    // Cumulative acquisition stats since the source was created.
    long long frames_delivered = 0;
    long long frames_dropped   = 0;  // incomplete/invalid deliveries
    long long restarts         = 0;  // stream restarts (restart-on-stall)
};

// Abstraction over the camera array. Implemented by VimbaCameraSource (Allied
// Vision Vimba X) and MockCameraSource (synthetic frames, no hardware).
//
// Completed frames are delivered to the callback set via setFrameCallback();
// the consumer (ImagePipeline) encodes and stores them.
class ICameraSource {
public:
    using FrameCallback = std::function<void(const Frame&)>;

    virtual ~ICameraSource() = default;

    virtual void open()  = 0;   // acquire/open cameras
    virtual void close() = 0;
    virtual void start() = 0;   // begin acquisition
    virtual void stop()  = 0;

    // Capture one image and deliver it to the frame callback. Returns true on
    // success. The camera free-runs, so this hands over the freshest complete
    // frame; it returns false when no frame newer than the last one is available
    // yet, and the caller simply retries.
    virtual bool trigger() = 0;

    // Apply a profile to one camera, identified by its index in the order the
    // source opened them (the same index Frame::cam_id carries). The backend
    // loads the profile's settings XML through its SDK - see CameraProfile.h.
    // Default: no-op, for sources with nothing to configure.
    virtual bool setProfile(int /*camera_index*/, const CameraProfile& /*profile*/) {
        return false;
    }

    virtual void setFrameCallback(FrameCallback cb) = 0;

    // ---- For the keep rule (SettleRule.h) ---------------------------------------
    // The most recent frames camera 0 delivered, with their brightness, exposure
    // and gain. Sequence numbers count up for the session; framesSince(n) returns
    // the frames after n, oldest first (only the last few dozen are kept).
    // frameSeq() is the newest sequence number. Default: no frames, and the scan
    // keeps its fixed settle wait.
    virtual uint64_t                frameSeq() { return 0; }
    virtual std::vector<FrameStats> framesSince(uint64_t /*after*/) { return {}; }
    // A numeric camera feature (IntensityControllerTarget, ExposureAutoMax...).
    // False if the camera has no such feature.
    virtual bool readFeature(int /*camera_index*/, const std::string& /*name*/, double& /*value*/) {
        return false;
    }

    // Number of cameras this source manages.
    virtual int cameraCount() const = 0;

    // Live identity/telemetry/stats per camera, for the expanded camera view.
    // Default: none. Implementations may refresh a throttled cache, so non-const.
    virtual std::vector<CameraDeviceInfo> deviceInfo() { return {}; }

    // ---- For `test camera` only ------------------------------------------------
    // The camera's configuration otherwise changes through setProfile() and
    // nothing else; these let the self-test drive a camera to known extremes and
    // then put it back. Defaults: unsupported, which the test reports as "not
    // checked" rather than as a fault.

    // The next complete frame from one camera that arrives after this call, into
    // `out`. False if none arrives within `timeout_ms`. The stream must be
    // running (start()); this does not start it.
    virtual bool grabFrame(int /*camera_index*/, Frame& /*out*/, int /*timeout_ms*/) {
        return false;
    }

    // Set one camera feature by its GenICam name, the value given as text ("Off",
    // "66.4", "true"). False if the camera has no such feature or refuses it.
    virtual bool setFeature(int /*camera_index*/, const std::string& /*name*/,
                            const std::string& /*value*/) {
        return false;
    }

    // A numeric feature's range. False if absent or not numeric.
    virtual bool featureRange(int /*camera_index*/, const std::string& /*name*/,
                              double& /*min*/, double& /*max*/) {
        return false;
    }

    // Put a camera back on the profile it was configured with, undoing every
    // setFeature() since. False if that failed - which leaves the camera on
    // settings nobody chose, so callers must say so loudly.
    virtual bool restoreProfile(int /*camera_index*/) { return false; }

    // Reboot one camera (GenICam DeviceReset), reopen it and put it back on its
    // profile. The last resort for a stream that nothing else will restart - and
    // the operator's `camera reset`. Blocks while the camera comes back (seconds).
    virtual bool resetCamera(int /*camera_index*/) { return false; }
};

}  // namespace fgc