_setup_env() {
    echo "Setting up the environment..."
    WD=$(cd `dirname "$1"` && pwd)
    SOURCEDIR=$(realpath "${WD}/../..")
    BUILDROOT=$(realpath "${WD}/../../$2-build")
    DESKTOPROOT=${BUILDROOT}/desktop
    METAROOT=${BUILDROOT}/meta
    SERVERROOT=${BUILDROOT}/server
    WEBROOT=${BUILDROOT}/web
    DISTROOT=$(realpath "${WD}/../../dist")
    APP_RELEASE=`grep "^APP_RELEASE" web/config.py | cut -d"=" -f2 | sed 's/ //g'`
    APP_REVISION=`grep "^APP_REVISION" web/config.py | cut -d"=" -f2 | sed 's/ //g'`
    APP_NAME=`grep "^APP_NAME" web/config.py | cut -d"=" -f2 | sed "s/'//g" | sed 's/^ //' | sed 's/ //g' | tr '[:upper:]' '[:lower:]'`
    APP_LONG_VERSION=${APP_RELEASE}.${APP_REVISION}
    APP_SHORT_VERSION=`echo ${APP_LONG_VERSION} | cut -d . -f1,2`
    APP_SUFFIX=`grep "^APP_SUFFIX" web/config.py | cut -d"=" -f2 | sed 's/ //g' | sed "s/'//g"`
    if [ ! -z ${APP_SUFFIX} ]; then
        APP_LONG_VERSION=${APP_LONG_VERSION}-${APP_SUFFIX}
    fi
}

_cleanup() {
    echo "Cleaning up the old environment and app..."
    if test -f ${SOURCEDIR}/runtime/pgAdmin4; then
        rm -rf ${SOURCEDIR}/runtime/pgAdmin4
    fi
    if test -d ${BUILDROOT}; then
        rm -rf ${BUILDROOT}
    fi
    rm -f ${DISTROOT}/pgadmin4*.$1
}

_setup_dirs() {
    echo "Creating output directories..."
    test -d ${BUILDROOT} || mkdir ${BUILDROOT}
    test -d ${DESKTOPROOT} || mkdir ${DESKTOPROOT}
    test -d ${METAROOT} || mkdir ${METAROOT}
    test -d ${SERVERROOT} || mkdir ${SERVERROOT}
    test -d ${WEBROOT} || mkdir ${WEBROOT}
    test -d ${DISTROOT} || mkdir ${DISTROOT}
}

_create_python_virtualenv() {
    echo "Creating the virtual environment..."

    cd ${SERVERROOT}

    # Create the required directories
    mkdir -p "usr/${APP_NAME}"
    cd "usr/${APP_NAME}"

    # Create the blank venv
    python3 -m venv venv
    source venv/bin/activate

    # Make sure we have the wheel package present, as well as the latest pip
    pip3 install --upgrade pip
    pip3 install wheel

    # Install the requirements
    pip3 install --no-cache-dir --no-binary psycopg2 -r ${SOURCEDIR}/requirements.txt

    # Fixup the paths in the venv activation scripts
    sed -i 's/VIRTUAL_ENV=.*/VIRTUAL_ENV="\/usr\/pgadmin4\/venv"/g' venv/bin/activate
    sed -i 's/setenv VIRTUAL_ENV .*/setenv VIRTUAL_ENV "\/usr\/pgadmin4\/venv"/g' venv/bin/activate.csh
    sed -i 's/set -gx VIRTUAL_ENV .*/set -gx VIRTUAL_ENV "\/usr\/pgadmin4\/venv"/g' venv/bin/activate.fish

    # Remove __pycache__
    find . -name "__pycache__" -type d -print0 | xargs -0 rm -rf

    # Fixup hash bangs
    sed -i 's/#!.*\/python3/#\!\/usr\/pgadmin4\/venv\/bin\/python3/g' venv/bin/*

    # Figure out some paths for use when completing the venv
    # Use "python3" here as we want the venv path
    PYMODULES_PATH=$(python3 -c "from distutils.sysconfig import get_python_lib; print(get_python_lib())")
    DIR_PYMODULES_PATH=`dirname ${PYMODULES_PATH}`

    # Use /usr/bin/python3 here as we want the system path
    if [ $1 == "debian" ]; then
        PYSYSLIB_PATH=$(/usr/bin/python3 -c "import sys; print('%s/lib/python%d.%.d' % (sys.prefix, sys.version_info.major, sys.version_info.minor))")
    else
        PYSYSLIB_PATH=$(/usr/bin/python3 -c "import sys; print('%s/lib64/python%d.%.d' % (sys.prefix, sys.version_info.major, sys.version_info.minor))")
    fi

    # Symlink in the rest of the Python libs. This is required because the runtime
    # will clear PYTHONHOME for safety, which has the side-effect of preventing
    # it from finding modules that are not explicitly included in the venv
    cd ${DIR_PYMODULES_PATH}

    # Files
    for FULLPATH in ${PYSYSLIB_PATH}/*.py; do
        FILE=${FULLPATH##*/}
        if [ ! -e ${FILE} ]; then
           ln -s ${FULLPATH} ${FILE}
        fi
    done

    # Paths
    for FULLPATH in ${PYSYSLIB_PATH}/*/; do
        FULLPATH=${FULLPATH%*/}
        FILE=${FULLPATH##*/}
        if [ ! -e ${FILE} ]; then
            ln -s ${FULLPATH} ${FILE}
        fi
    done

    # Remove tests
    cd site-packages
    find . -name "test" -type d -print0 | xargs -0 rm -rf
    find . -name "tests" -type d -print0 | xargs -0 rm -rf

    # Link the python<version> directory to python so that the private environment path is found by the application.
    if test -d ${DIR_PYMODULES_PATH}; then
        ln -s $(basename ${DIR_PYMODULES_PATH}) ${DIR_PYMODULES_PATH}/../python
    fi
}

_build_runtime() {
    echo "Assembling the desktop runtime..."

    # Get a fresh copy of nwjs.
    # NOTE: The nw download servers seem to be very unreliable, so at the moment we're using wget
    #       in a retry loop as Yarn/Npm don't seem to like that.

    # YARN:
    # yarn add --cwd "${BUILDROOT}" nw
    # YARN END

    # WGET:
    NW_VERSION=$(yarn info nw | grep latest | awk -F "'" '{ print $2}')

    pushd "${BUILDROOT}" > /dev/null
        while true;do
            wget https://dl.nwjs.io/v${NW_VERSION}/nwjs-v${NW_VERSION}-linux-x64.tar.gz && break
            rm nwjs-v${NW_VERSION}-linux-x64.tar.gz
        done
        tar -zxvf nwjs-v${NW_VERSION}-linux-x64.tar.gz
    popd > /dev/null
    # WGET END

    # Copy nwjs into the staging directory
    mkdir -p "${DESKTOPROOT}/usr/${APP_NAME}/bin"

    # YARN:
    # cp -r "${BUILDROOT}/node_modules/nw/nwjs"/* "${DESKTOPROOT}/usr/${APP_NAME}/bin"
    #  YARN END

    # WGET:
    cp -r "${BUILDROOT}/nwjs-v${NW_VERSION}-linux-x64"/* "${DESKTOPROOT}/usr/${APP_NAME}/bin"
    # WGET END

    mv "${DESKTOPROOT}/usr/${APP_NAME}/bin/nw" "${DESKTOPROOT}/usr/${APP_NAME}/bin/${APP_NAME}"

    cp -r "${SOURCEDIR}/runtime/assets" "${DESKTOPROOT}/usr/${APP_NAME}/bin/assets"
    cp -r "${SOURCEDIR}/runtime/src" "${DESKTOPROOT}/usr/${APP_NAME}/bin/src"

    cp "${SOURCEDIR}/runtime/package.json" "${DESKTOPROOT}/usr/${APP_NAME}/bin/"
    yarn --cwd "${DESKTOPROOT}/usr/${APP_NAME}/bin" install --production=true

    # Create the icon
    mkdir -p "${DESKTOPROOT}/usr/share/icons/hicolor/128x128/apps/"
    cp "${SOURCEDIR}/pkg/linux/pgadmin4-128x128.png" "${DESKTOPROOT}/usr/share/icons/hicolor/128x128/apps/${APP_NAME}.png"
    mkdir -p "${DESKTOPROOT}/usr/share/icons/hicolor/64x64/apps/"
    cp "${SOURCEDIR}/pkg/linux/pgadmin4-64x64.png" "${DESKTOPROOT}/usr/share/icons/hicolor/64x64/apps/${APP_NAME}.png"
    mkdir -p "${DESKTOPROOT}/usr/share/icons/hicolor/48x48/apps/"
    cp "${SOURCEDIR}/pkg/linux/pgadmin4-48x48.png" "${DESKTOPROOT}/usr/share/icons/hicolor/48x48/apps/${APP_NAME}.png"
    mkdir -p "${DESKTOPROOT}/usr/share/icons/hicolor/32x32/apps/"
    cp "${SOURCEDIR}/pkg/linux/pgadmin4-32x32.png" "${DESKTOPROOT}/usr/share/icons/hicolor/32x32/apps/${APP_NAME}.png"
    mkdir -p "${DESKTOPROOT}/usr/share/icons/hicolor/16x16/apps/"
    cp "${SOURCEDIR}/pkg/linux/pgadmin4-16x16.png" "${DESKTOPROOT}/usr/share/icons/hicolor/16x16/apps/${APP_NAME}.png"

    mkdir -p "${DESKTOPROOT}/usr/share/applications"
    cp "${SOURCEDIR}/pkg/linux/pgadmin4.desktop" "${DESKTOPROOT}/usr/share/applications"
}

_build_docs() {
    echo "Building the documentation..."
    cd "${SERVERROOT}" && mkdir -p "usr/${APP_NAME}/share/docs/en_US/html"
    cd "${SOURCEDIR}/docs/en_US"
    python3 build_code_snippet.py
    SYS_PYTHONPATH=$(/usr/bin/python3 -c "import sys; print(':'.join([p for p in sys.path if p]))")
    if [ $1 == "redhat" -a "${OS_VERSION}" == "7" ]; then
            PYTHONPATH=$PYTHONPATH:${SYS_PYTHONPATH} python3 /usr/local/bin/sphinx-build . "${SERVERROOT}/usr/${APP_NAME}/share/docs/en_US/html"
    else
        PYTHONPATH=$PYTHONPATH:${SYS_PYTHONPATH} python3 -msphinx . "${SERVERROOT}/usr/${APP_NAME}/share/docs/en_US/html"
    fi
}

_copy_code() {
    echo "Copying the server code..."

    # Remove any TCL-related files that may cause us problems
    find "${SERVERROOT}/usr/${APP_NAME}/venv/" -name "_tkinter*" -print0 | xargs -0 rm -rf

    pushd ${SOURCEDIR}/web > /dev/null
        yarn install
        yarn run bundle
    popd > /dev/null

    # copy the web directory to the bundle as it is required by runtime
    cp -r "${SOURCEDIR}/web" "${SERVERROOT}/usr/${APP_NAME}/web/"
    cp "${SOURCEDIR}/pkg/linux/config_distro.py" "${SERVERROOT}/usr/${APP_NAME}/web/"
    cd "${SERVERROOT}/usr/${APP_NAME}/web/"
    rm -f pgadmin4.db config_local.*
    rm -rf karma.conf.js package.json node_modules/ regression/ tools/ pgadmin/static/js/generated/.cache
    find . -name "tests" -type d -print0 | xargs -0 rm -rf
    find . -name "feature_tests" -type d -print0 | xargs -0 rm -rf
    find . -name "__pycache__" -type d -print0 | xargs -0 rm -rf

    # License files
    cp "${SOURCEDIR}/LICENSE" "${SERVERROOT}/usr/${APP_NAME}/"
    cp "${SOURCEDIR}/DEPENDENCIES" "${SERVERROOT}/usr/${APP_NAME}/"

    # Web setup script
    mkdir -p "${WEBROOT}/usr/${APP_NAME}/bin/"
    cp "${SOURCEDIR}/pkg/linux/setup-web.sh" "${WEBROOT}/usr/${APP_NAME}/bin/"

    # Ensure our venv will use the correct Python interpreter, even if the
    # user has configured an alternative default.
    # DO THIS LAST!
    cd "${SERVERROOT}/usr/${APP_NAME}/venv/bin"
    PYTHON_INTERPRETER=$(/usr/bin/python3 -c "import os, sys; print(os.path.realpath(sys.executable))")
    PYTHON_VERSION=$(/usr/bin/python3 -c "import sys; print('%d.%d' % (sys.version_info.major, sys.version_info.minor))")
    rm python && ln -s python3 python
    rm python${PYTHON_VERSION} && ln -s python3 python${PYTHON_VERSION}
    rm python3 && ln -s "${PYTHON_INTERPRETER}" python3
}