build_megasync_qt6.sh

#!/usr/bin/env bash
set -euo pipefail

# ============================ config ============================
SRC_DIR="$HOME/MEGAsync"            # where to clone the app
VCPKG_ROOT="$HOME/mega/vcpkg"                     # your existing vcpkg
QT_PREFIX="/usr/lib64/qt6"                        # Gentoo Qt6
BUILD_DIR="$SRC_DIR/build_release"
INSTALL_PREFIX="/opt/megasync-qt6"               # self-contained install dir
BRANCH="feature/qt6-migration"
APP_FORK="git@github.com:dakk/MEGAsync.git"
SDK_FORK="git@github.com:dakk/mega-sdk.git"
JOBS="$(nproc)"

# ===================== 0. vcpkg (clone if missing) =====================
if [ ! -e "$VCPKG_ROOT/bootstrap-vcpkg.sh" ]; then
    echo ">> vcpkg not found at $VCPKG_ROOT — cloning"
    git clone https://github.com/microsoft/vcpkg "$VCPKG_ROOT"
fi

# ===================== 1. clone your MEGAsync qt6 branch (idempotent) =====================
if [ ! -e "$SRC_DIR/CMakeLists.txt" ]; then
    rm -rf "$SRC_DIR"
    git clone -b "$BRANCH" "$APP_FORK" "$SRC_DIR"
fi
cd "$SRC_DIR"

# ===================== 2. SDK from YOUR fork's qt6 branch (idempotent) =====================
# (.gitmodules points at upstream meganz/sdk, which lacks the Qt6 binding fix.)
if [ ! -e src/MEGASync/mega/CMakeLists.txt ]; then
    rm -rf src/MEGASync/mega
    git clone --recursive -b "$BRANCH" "$SDK_FORK" src/MEGASync/mega
fi

# ===================== 3. configure (Release, relocatable RPATH) =====================
cmake -DVCPKG_ROOT="$VCPKG_ROOT" \
      -DCMAKE_PREFIX_PATH="$QT_PREFIX" \
      -DCMAKE_BUILD_TYPE=Release \
      -DCMAKE_INSTALL_LIBDIR=lib \
      -DCMAKE_INSTALL_RPATH='$ORIGIN/../lib' \
      -S "$SRC_DIR" -B "$BUILD_DIR"

# ===================== 4. build (app + isolated gfxworker + resources) =====================
cmake --build "$BUILD_DIR" --target MEGAsync -j"$JOBS"

# ===================== 5. install to /opt (needs root) =====================
sudo cmake --install "$BUILD_DIR" --prefix "$INSTALL_PREFIX"

# ===================== 6. discover where the binary and libs actually landed =====================
# (GNUInstallDirs may put libs in lib/ or lib64/; don't assume.)
BIN_PATH="$(sudo find "$INSTALL_PREFIX" -type f -name megasync -print -quit)"
LIB_PATH="$(sudo find "$INSTALL_PREFIX" -type f -name 'libavutil.so*' -print -quit)"
if [ -z "$BIN_PATH" ] || [ -z "$LIB_PATH" ]; then
    echo "ERROR: could not locate installed binary or libs under $INSTALL_PREFIX:" >&2
    echo "  binary='$BIN_PATH'  lib='$LIB_PATH'" >&2
    sudo find "$INSTALL_PREFIX" -maxdepth 2 | sort >&2
    exit 1
fi
LIB_DIR="$(dirname "$LIB_PATH")"
echo ">> binary: $BIN_PATH"
echo ">> libs:   $LIB_DIR"

# make the bundled vcpkg libs resolve each other relative to themselves
sudo find "$LIB_DIR" -maxdepth 1 -name '*.so*' -type f \
     -exec patchelf --set-rpath '$ORIGIN' {} \;

# ===================== 7. launcher + PATH symlink =====================
# The launcher points LD_LIBRARY_PATH at the real lib dir, so it works no matter
# whether the libs landed in lib/ or lib64/.
sudo tee "$INSTALL_PREFIX/run-megasync.sh" >/dev/null <<EOF
#!/usr/bin/env bash
export LD_LIBRARY_PATH="$LIB_DIR\${LD_LIBRARY_PATH:+:\$LD_LIBRARY_PATH}"
exec "$BIN_PATH" "\$@"
EOF
sudo chmod +x "$INSTALL_PREFIX/run-megasync.sh"
sudo ln -sf "$INSTALL_PREFIX/run-megasync.sh" /usr/local/bin/megasync-qt6

echo
echo "Installed to $INSTALL_PREFIX"
echo "  binary:    $BIN_PATH"
echo "  libs:      $LIB_DIR"
echo "  resources: $INSTALL_PREFIX/share/megasync/resources/*.rcc"
echo "Run:  megasync-qt6        (or  $INSTALL_PREFIX/run-megasync.sh)"