// SPDX-FileCopyrightText: 2025 Filip Leonarski, Paul Scherrer Institute <filip.leonarski@psi.ch>
// SPDX-License-Identifier: GPL-3.0-only

#include "JFJochSimpleImage.h"
#include <QGraphicsScene>
#include <QGraphicsPixmapItem>
#include <QMouseEvent>
#include <QtMath>
#include <cstring>
#include <algorithm>

#include "../../common/JFJochException.h"

JFJochSimpleImage::JFJochSimpleImage(QWidget *parent)
    : JFJochImage(parent) {
    auto *scn = new QGraphicsScene(this);
    setScene(scn);

    // Keep overlays in pixel units independent of zoom (for labels font sizing)
    setViewportUpdateMode(QGraphicsView::FullViewportUpdate);
}

void JFJochSimpleImage::setImage(std::shared_ptr<const SimpleImage> img) {
    if (img) {
        image_ = std::move(img);
        loadImageInternal();
        GeneratePixmap();
        Redraw();
        CalcROI();
    } else {
        image_.reset();
        W = 0; H = 0;
        if (scene())
            scene()->clear();
        CalcROI();
    }
}

void JFJochSimpleImage::mouseHover(QMouseEvent *event) {
    if (image_) {
        const QPointF scenePos = mapToScene(event->pos());
        // Hover feedback / status bar display
        if ((scenePos.x() >= 0)
            && (scenePos.x() < image_->image.GetWidth())
            && (scenePos.y() >= 0)
            && (scenePos.y() < image_->image.GetHeight())) {
            const auto ix = int(scenePos.x());
            const auto iy = int(scenePos.y());
            const auto idx = iy * int(image_->image.GetWidth()) + ix;
            if (idx >= 0 && idx < int(image_fp.size()))
                emit writeStatusBar(QString("x=%1 y=%2 I=%3")
                                    .arg(scenePos.x(), 0, 'f', 1)
                                    .arg(scenePos.y(), 0, 'f', 1)
                                    .arg(image_fp[size_t(idx)]), 3000);
        } else {
            emit writeStatusBar("", 1000);
        }
    }
}

template<class T>
void JFJochSimpleImage::loadImageInternal(const uint8_t *input) {
    const size_t W = image_->image.GetWidth();
    const size_t H = image_->image.GetHeight();

    auto ptr = reinterpret_cast<const T *>(input);
    
    for (int i = 0; i < W * H; i++)
        image_fp[i] = static_cast<float>(ptr[i]);
}

void JFJochSimpleImage::loadImageInternal() {
    W = image_->image.GetWidth();
    H = image_->image.GetHeight();
    if (W == 0 || H == 0) return;

    image_fp.resize(W * H);

    std::vector<uint8_t> image_buffer;

    // Access uncompressed data
    const uint8_t *src = image_->image.GetUncompressedPtr(image_buffer);
    const auto mode = image_->image.GetMode();

    switch (mode) {
        case CompressedImageMode::Uint8:
            loadImageInternal<uint8_t>(src);
            break;
        case CompressedImageMode::Int8:
            loadImageInternal<int8_t>(src);
            break;
        case CompressedImageMode::Uint16:
            loadImageInternal<uint16_t>(src);
            break;
        case CompressedImageMode::Int16:
            loadImageInternal<int16_t>(src);
            break;
        case CompressedImageMode::Uint32:
            loadImageInternal<uint32_t>(src);
            break;
        case CompressedImageMode::Int32:
            loadImageInternal<int32_t>(src);
            break;
        case CompressedImageMode::Float32:
            loadImageInternal<float>(src);
            break;
        case CompressedImageMode::Float64:
            loadImageInternal<double>(src);
            break;
        default:
            throw JFJochException(JFJochExceptionCategory::InputParameterInvalid, "Image format not supported");
    }
}