#pragma once

#include <QByteArray>
#include <QString>

// Turns a picked image into a file the gallery's upload API accepts.
//
// Three things must be true of the result: no EXIF (the gallery publishes the
// uploaded file verbatim as its full-size download, so embedded GPS would be
// public), a .jpg or .png extension (server.go rejects anything else, HEIC
// included), and under nginx's 20M body cap.
//
// JPEG and PNG take a lossless route — whole metadata segments are dropped
// without touching the compressed image data — so the published file keeps the
// original sensor pixels. Anything else, or a file whose EXIF orientation must
// be baked in, is decoded and re-encoded as JPEG (HEIC via Qt's qtimageformats
// plugin). The strippers are a direct port of the Android app's.
class ImagePrep
{
public:
    struct Prepared {
        QString filePath;
        QString note; // non-empty when the app departed from a byte-exact copy
        QString error;
        bool ok() const { return error.isEmpty(); }
    };

    // Writes the upload-ready file into cacheDir as baseName.(jpg|png).
    static Prepared prepare(const QString &sourcePath, const QString &cacheDir,
                            const QString &baseName);

private:
    static QByteArray stripJpegSegments(const QByteArray &src); // empty on parse failure
    static QByteArray stripPngChunks(const QByteArray &src);
    static bool isJpeg(const QByteArray &b);
    static bool isPng(const QByteArray &b);
};