#!/bin/bash

set -eu
set -o pipefail
# set -x

export which_pythons=""
export cleanup=True
export do_gtk=True
export do_numerical=True
export macos_openssl=openssl@3

# Turn up automake verbosity
export V=1
# Turn up cmake verbosity
export VERBOSE=1

initial_dir="$(pwd)"

PATH="$initial_dir/bin:$PATH"
export PATH

function usage
{
    retval="$1"
    (
        echo "Usage: $0 --which-pythons 'python-2.7 python-3.4'"
        echo "       $0 --which-pythons all"
        echo "          --skip-gtk"
        echo "          --skip-numerical"
        echo "          --skip-cleanup do not remove build temporaries"
    ) 1>&2
    exit "$retval"
}

while [ "$#" -ge 1 ]
do
    case "$1" in
        --which-pythons)
            which_pythons="$2"
            shift
            ;;
        --skip-gtk)
            do_gtk=False
            ;;
        --skip-numerical)
            do_numerical=False
            ;;
        --skip-cleanup)
            cleanup=False
            ;;
        -h|--help)
            usage 0
            ;;
        *)
            echo "$0: Unrecognized option: $1" 1>&2
            usage 1
            ;;
    esac
    shift
done

if [ "$(whoami)" != root ]
then
	echo "$0: You must run me as root" 1>&2
	exit 1
fi

(
    cd cobble
    make install
)

# shellcheck disable=SC2230
if ! which cobble > /dev/null 2>&1
then
    echo "$0: I require cobble. You can get cobble from http://stromberg.dnsalias.org/~strombrg/cobble.html" 1>&2
    exit 1
fi

if [ "${which_pythons:-}" = "" ]
then
    echo "$0: --which-pythons is a required option" 1>&2
    echo "Give it 'all' or a space-separated list like 'python-2.7 python-3.4'"
    usage 1
fi

# shellcheck disable=SC2155
export original_cwd=$(set -eu; set -o pipefail; pwd)

function all_pythons
{
    echo python-3.11
    echo python-3.10
    echo python-3.9
    echo python-3.8
    echo python-3.7
    echo python-3.6
    echo python-3.5
    echo python-3.4
    echo python-3.3
    echo python-3.2
    echo python-3.1
    echo python-3.0
    echo python-2.7
    echo python-2.6
    echo python-2.5
    echo python-2.4
    echo python-2.3
    echo python-2.2
    echo python-2.1
    echo python-2.0
    echo python-1.6
    echo python-1.5
    echo python-1.4
    echo python-1.3
    echo python-1.2
    echo python-1.1
    echo python-1.0
    echo python-0.9
}

case "$which_pythons" in
    all)
        which_pythons=$(all_pythons)
        ;;
    *)
        ;;
esac

# Intentionally not quoting $which_pythons
for python in $which_pythons
do
    case "$python" in
        c*)
            echo "$0: $python starts with a c, but must not" 1>&2
            usage 1
            ;;
    esac
    case "$python" in
        *-*)
            ;;
        *)
            echo "$0: $python does not contain a -, but must" 1>&2
            usage 1
            ;;
    esac
done

function getlogin
{
	python3 -c '
import os
print(os.getlogin())
'
}

if type apt-get > /dev/null 2>&1
then
    # gcc-multilib is to get a 32 bit build environment, since some of the older pythons segfault sometimes when
    # built for 64 bit.
    # Note that meson from apt-get was too old.  I had to build one myself. It's still listed here, hoping
    # one day that won't be necessary.
    # libbonobo2-dev \
    apt-get -y install \
        autoconf \
        automake \
        autopoint \
        bison \
        build-essential \
        clang \
        cmake \
        flex \
        g++ \
        gcc-multilib \
        gfortran \
        gir1.2-gtk-4.0 \
        git \
        gperf \
        gtk-doc-tools \
        intltool \
        libbz2-dev \
        libcairo2-dev \
        libdb-dev \
        libdbus-glib-1-dev \
        libegl1-mesa-dev \
        libepoxy-dev \
        libexpat1-dev \
        libffi-dev \
        libfribidi-dev \
        libgconf2-dev \
        libgdbm-dev \
        libgirepository1.0-dev \
        liblzma-dev \
        libmount-dev \
        libpng-dev \
        libreadline-dev \
        libsasl2-dev \
        libsqlite3-dev \
        libssl-dev \
        libtool \
        libwayland-dev \
        libxext-dev \
        libxinerama-dev \
        libxkbcommon-dev \
        libxml2-utils \
        libxrandr-dev \
        libxtst-dev \
        mesa-common-dev \
        meson \
        pkg-config \
        python3-dev \
        python3-setuptools \
        ragel \
        sqlite3 \
        swig
    # This is no longer available nor required in Mint 18
    apt-get install libXi-dev || true
    have_ragel=True
    have_xinput=True
elif type yum > /dev/null 2>&1
then
    # Worked with CentOS 7.
    yum -y groupinstall "Development Tools"
    yum -y install \
        openssl-devel \
        libffi-devel \
        cmake \
        expat-devel \
        libpng-devel \
        dbus-glib-devel \
        libXtst-devel \
        bzip2-devel \
        xz-devel \
        ncurses-devel \
        wget \
        libXi-devel \
        libmount-devel \
        colm-devel \
        libwayland-devel
    have_ragel=False
    have_xinput=False
elif type brew > /dev/null 2>&1
then
	su "$(getlogin)" -c "brew install $macos_openssl zlib readline xz meson"
	# cp /usr/local/opt/openssl@1.1/lib/pkgconfig/*.pc /usr/local/lib/pkgconfig/.
	# cp /usr/local/opt/zlib/lib/pkgconfig/*.pc /usr/local/lib/pkgconfig/.
else
    echo "$0: None of apt-get, yum or brew found" 1>&2
    exit 1
fi

#function get_includes
#(
#    find /usr/local/$which_python/include -type d -print | sed 's/^/-I/' | tr '\012' ' '
#)

function less_than
{
    x="$1"
    y="$2"
    if echo "$x"-"$y" | bc | grep -Eq '^-'
    then
        return 0
    else
        return 1
    fi
}

function autoconf_downrev
{
    autoconf_version=$(autoconf --version | head -1 | awk ' { print $NF }')
    if less_than "$autoconf_version" 2.64
    then
        return 0
    else
        return 1
    fi
}

function pygi
(
    set -eu
    set -o pipefail

    cd "$initial_dir"/pygi/meson
    cobble
    do-inst

    # This seems to help pkg-config find the newer files.
    cd "$initial_dir"/pygi/pkg-config
    cobble
    do-inst

    export PKG_CONFIG="/usr/local/c$which_python/bin/pkg-config"
    PKG_CONFIG_PATH="$(set -eu; build_pkg_config_path)"
    export PKG_CONFIG_PATH
    export PATH=/usr/local/c"$which_python"/bin:$PATH

    # build and install glib
    cd "$initial_dir"/pygi/glib
    cobble
    do-inst

    # build and install gobject-introspection
    cd "$initial_dir"/pygi/gobject-introspection
    cobble
    do-inst

    # According to:
    # https://www.linuxquestions.org/questions/linux-from-scratch-13/make-%2A%2A%2A-%5B-sources-blfs-freetype-2-6-3-objs-autofit-lo%5D-error-1-a-4175583724/
    # ...we need to install freetype twice, once before harfbuzz, once after.
    # build and install freetype2, seems to be needed by harfbuzz
    cd "$initial_dir"/pygi/freetype2
    cobble
    do-inst

    # This too appears to be included in GTK+ now - but do we benefit from it?
    # On zareason-strata7440, I have it in /usr/local/lib, but on dell-inspiron-3530 I do not.
    # And the build succeeds on zs7 but not di3.
    # build and install harfbuzz, cairo seems to need it
    cd "$initial_dir"/pygi/harfbuzz
    cobble
    do-inst

    # build and install freetype2, seems to be needed by cairo
    cd "$initial_dir"/pygi/freetype2
    cobble
    do-inst

    # build and install atk
    # GTK+ uses this, and it has a typelib, so we probably need it to come after gobject-introspection
    # Also, pixman uses it, and we do not want pixman trying to get the OS-provided ATK
    cd "$initial_dir"/pygi/atk
    cobble
    do-inst

    # build and install pixman, seems to be needed by cairo (?)
    cd "$initial_dir"/pygi/pixman
    cobble
    do-inst

    # build and install fontconfig, building this after cairo gave an unresolved external
    # cairo_ft_font_options_substitute
    cd "$initial_dir"/pygi/fontconfig
    cobble
    do-inst

    # build and install cairo
    # pango seems to need cairo, so we build cairo before pango
    cd "$initial_dir"/pygi/cairo
    cobble
    do-inst

    # build and install pango
    # This was griping about not having gobject-introspection...
    # Pango appears to be included in GTK+'s source distribution now; let's use that.
    cd "$initial_dir"/pygi/pango
    cobble
    do-inst

    # We redo this, because pango appears to be putting things in a different spot
    PKG_CONFIG_PATH="$(set -eu; build_pkg_config_path)"
    export PKG_CONFIG_PATH

    case "$have_ragel" in
        True)
            ;;
        False)
            # build and install ragel; we were unable to get it from a package manager
            cd "$initial_dir"/pygi/ragel
            cobble
            do-inst
            ;;
        *)
            echo "$0: Internal error: \$have_ragel is neither True nor False" 1>&2
            exit 1
            ;;
    esac

    case "$have_xinput" in
        True)
            ;;
        False)
            # build and install ragel; we were unable to get it from a package manager
            cd "$initial_dir"/pygi/xinput
            cobble
            do-inst
            ;;
        *)
            echo "$0: Internal error: \$have_xinput is neither True nor False" 1>&2
            exit 1
            ;;
    esac

    # If autoconf is too old, install that too
    # Actually, autoconf hasn't changed in years, but I want to try building it into the cpython hierarchy
    # to see if that'll help with a "error: HAVE_INTROSPECTION does not appear in AM_CONDITIONAL" I am
    # getting.
    # if autoconf_downrev
    # then
    cd "$initial_dir"/pygi/autoconf
    cobble
    do-inst
    # fi

    # build and install libtiff
    cd "$initial_dir"/pygi/libtiff
    cobble
    do-inst

    # build and install libjpeg
    cd "$initial_dir"/pygi/libjpeg
    cobble
    do-inst

    # build and install gdk-pixbuf
    cd "$initial_dir"/pygi/gdk-pixbuf
    cobble
    do-inst

    # Build and install at-spi - GTK+ requires this.  We need it for
    # atk-bridge, perhaps more.  Oddly, this requires GTK+-2.0!
    # cd "$initial_dir"/pygi/at-spi
    # cobble
    # do-inst

    # Build and install at-spi2-core
    cd "$initial_dir"/pygi/at-spi2-core
    cobble
    do-inst

    # Build and install spi2-atk - GTK+ requires this (?) for atk-bridge (?)
    cd "$initial_dir"/pygi/at-spi2-atk
    cobble
    do-inst

    # Build and install graphene - GTK+ appears to require this
    cd "$initial_dir"/pygi/graphene
    cobble
    do-inst

    # We redo this, because pango appears to be putting things in a different spot
    PKG_CONFIG_PATH="$(set -eu; build_pkg_config_path)"
    export PKG_CONFIG_PATH

    # build and install gtk+
    cd "$initial_dir"/pygi/gtk+
    cobble
    do-inst

    # This seems to want Gnome, which is more than I want to build
    # Build and install bonobo
    #cd "$initial_dir"/pygi/bonobo2
    #cobble
    #do-inst

    # Build and install pycairo.
    # Apparently these folks are going dual-codebase.
    case "$which_python" in
        python-2.*)
            # We no longer build py2cairo for python 2.x.
            ;;
        python-3.*) cd "$initial_dir"/pygi/pycairo ;;
        *)
            echo "Neither 2.x nor 3.x.  Has a lot of time passed, or is \$which_python misdefined?"
            exit 1
            ;;
    esac
    cobble
    'do-inst'

    # build and install pygi
    cd "$initial_dir"/pygi
    cobble
    do-inst

    # Clean up
    case "$cleanup" in
        True)
            rm -rf "$initial_dir"/pygi/*/src
            rm -rf "$initial_dir"/pygi/src
            ;;
        False)
            ;;
        *)
            echo "$0: Internal error 1: Invalid \$cleanup: $cleanup" 1>&2
            exit 1
            ;;
    esac
)

function pygobject_via_pip
{
    apt install 'libgirepository1.0-dev' 'gcc' 'libcairo2-dev' 'pkg-config' 'python3-dev' 'gir1.2-gtk-4.0'

    "$PIP" install pycairo

    "$PIP" install PyGObject
}

function install_setuptools
{
    set -x
    # pylint needs setuptools
    case "$which_python" in
        python-0.*|python-1.*|python-2.[0123456]|python-3.[01234567])
            # 3.[012] and python 2.[456] don't appear to have pip accessible via get-pip.py .
            # We pretend we have pip in a manner sometimes used successfully for ranlib.
            # 
            # ensurepip segfaults (!) on CPython 3.7 now (2023-07-04)
            PIP=true
            export PIP
            return
            ;;
        *)
            # 3.5 come with a pip installer - use that
            #
            # 2.7.9 also has the pip installer: ensurepip
            /usr/local/c"$which_python"/bin/python -m ensurepip
			export PIP="/usr/local/c$which_python/bin/python -m pip"
            # pip install virtualenv
            ;;
    esac

    # Make sure we have the latest version
    eval "$PIP install --upgrade pip"
}

function install_pylint
{
    case "$which_python" in
        python-3.[0123]|python-2.[0123456]|python-1.*|python-0.*)
            # pylint fails on cpython 3.[012]
            # pylint fails to install due to an isort issue in cpython 3.3
            # recent pylint (1.0) fails to build on 2.[45]
            :
            ;;
        *)
            # setup_py_install_pylint
            pip_install_pylint
            ;;
    esac
}

function install_pygments
{
    case "$which_python" in
        python-3.[0123456]|python-2.*|python-1.*|python-0.*)
            ;;
        *)
            eval "$PIP install pygments"
            ;;
    esac
}

function install_mypy
{
    case "$which_python" in
        @python-3.10)
            # 3.10 is apparently too-new for mypy
            ;;
        python-3.[012]|python-2.*|python-1.*|python-0.*)
            # mypy is not available for older cpythons
            :
            ;;
        *)
            # mypy-lang was renamed to just "mypy".
            # $PIP install mypy-lang
            eval "$PIP install mypy"
            ;;
    esac
}

function install_six
{
    # six is a compatibility module for python 2.x and 3.x
    case "$which_python" in
        python-2.[012345]|python-1.*|python-0.*)
            # six is not available for cpython 2.[45]
            :
            ;;
        *)
            eval "$PIP install six"
            ;;
    esac
}

function pip_install_pylint
{
    case "$which_python" in
        python-2.7)
            # Pylint is moving on from Python 2.x, but the older versions still work:
            # https://stackoverflow.com/questions/51746255/how-can-i-install-the-pylint-for-python2-7
            eval "$PIP install pylint==1.9.5"
            ;;
        *)
            eval "$PIP install pylint"
            ;;
    esac
}

function pip_install_flake8
{
    eval "$PIP install flake8"
}

function pip_install_pyflakes
{
    eval "$PIP install pyflakes"
}

function pip_install_pycodestyle
{
    eval "$PIP install pycodestyle"
}

function setup_py_install_pylint
{
    case "$which_python" in
        python-2.5)
            # install stringformat for str.format functionality
            (
                set -eu
                set -o pipefail
                cd pylint/stringformat
                cobble || true
                cd src
                /usr/local/c"$which_python"/bin/python setup.py install --no-compile
            )
            ;;
    esac

    # install logilab common
    (
        set -eu
        set -o pipefail
        cd pylint/common
        cobble || true
        cd src
        /usr/local/c"$which_python"/bin/python setup.py install --no-compile
    )

    # install logilab astroid
    (
        set -eu
        set -o pipefail
        cd pylint/astroid
        cobble || true
        cd src
        /usr/local/c"$which_python"/bin/python setup.py install --no-compile
    )

    # install pylint proper
    (
        set -eu
        set -o pipefail
        cd pylint
        cobble || true
        cd src
        /usr/local/c"$which_python"/bin/python setup.py install --no-compile
    )

    permissions_workaround
}

function python3_symlink
{
    # symlink python3 to python, if python3 present - for making scripts nice and consistent
    if ls /usr/local/c"$which_python"/bin/python3* > /dev/null 2>&1
    then
        (
            set -eu
            set -o pipefail
            cd /usr/local/c"$which_python"/bin
            # shellcheck disable=SC2010
            first=$(ls -f | grep -E '^python3[0-9\.]*$' | sort | head -1)
            ln -sf "$first" python
            # I had a case statement for this, but vim did not like it
            if echo "$which_python" | grep -Eq '^python-3'
            then
                if ! [ -e python3 ]
                then
                    ln -sf "$first" python3
                fi
            fi
            if ! [ -e pip ]
            then
                ln -sf pip3 pip
            fi
        )
    fi
}

function permissions_workaround
{
    # a workaround for a permissions issue
    # /usr/local/cpython-2.5/lib/python2.5/site-packages/logilab/astng/brain
    # shellcheck disable=SC2001
    sans_dash=$(set -eu; set -o pipefail; echo "$which_python" | sed -e 's/-//g')
    #sans_dash=${which_python//-/}
    dir="/usr/local/$which_python/lib/$sans_dash/site-packages/logilab/astng/brain"
    if [ -e "$dir" ]
    then
       chmod -v 644 "$dir"/*
    fi
}

function install_cython
{
    # install cython
    case "$which_python" in
        @python-3.9)
            # 3.9 alpha 3 is too new for cython
			return
			;;
	esac
    # shellcheck disable=SC2194
    case 2 in
        1)
            # This is the old way, with downloading, commiting and cobble'ing
            (
                set -eu
                set -o pipefail
                cd cython
                cobble
                cd src
				# shellcheck disable=SC2030
                export LDFLAGS="-L/usr/local/c$which_python/lib -Wl,-rpath -Wl,/usr/local/c$which_python/lib"
                /usr/local/c"$which_python"/bin/python setup.py build install
            )
            ;;
        2)
            # Cython doesn't appear to offer .tar.whatever downloads anymore.
            # So we get it from pypi.
            eval "$PIP install cython"
            ;;
    esac
}

function numerical_build
{
    (
    cd numerical
    directory=/usr/local/c"$which_python"
    export directory

    # shellcheck disable=SC2194
    case 1 in
        1)
            # build lapack using cmake
                (
                cd lapack
                cobble
                cd src
                cmake '-DCMAKE_INSTALL_PREFIX:PATH'="$directory" "$(pwd)"
                make
                cd ..
                'do-inst'
                rm -rf src
                )
            ;;
        2)
            # build lapack using make
                (
                cd lapack
                # This errors out on the lack of a make.inc - 'local-script' creates one
                cobble || true
                cd src
                # This assumes 'local-script.nopers' is 'local-script'
                sh -x '../local-script'
                cd ..
                'do-inst'
                rm -rf src
                )
            ;;
    esac

    # Build a BLAS
    # shellcheck disable=SC2194
    case openblas in
        openblas)
            # This uses traditional make, sans autoconf, sans cmake
            # This is a blas replacement, as well as a replacement for parts of lapack.
            # However, we tell it not to build any portions of lapack, instead relying on the real lapack, built above.
            (
                cd openblas
                cobble
                'do-inst'
                rm -rf src
            )
            ;;
        atlas)
            # This wants to build lapack, but I'm attempting to tell it not to so we can build lapack with cmake
            # build blas and atlas
            # This may not be working :), but we're relying on openblas anyway.
                (
                # atlas is a replacement for blas and parts of lapack
                cd atlas
                # This errors out about a make thing; we rely on that
                cobble || true
                'do-inst'
                cd ..
                rm -rf src
                )
            ;;
        *)
            echo "$0: Internal error: blas selection invalid" 1>&2
            exit 1
    esac

    # build suitesparse
        (
        cd suitesparse
        tar xvfp SuiteSparse-*.tar.xz

        cd SuiteSparse

        #INSTALL_LIB = /usr/local/lib
        #INSTALL_INCLUDE = /usr/local/include
        FILE=SuiteSparse_config/SuiteSparse_config.mk
        sed -i "s#^INSTALL_LIB = .*\$#INSTALL_LIB = $directory/lib#" "$FILE"
        sed -i "s#^INSTALL_INCLUDE = .*\$#INSTALL_INCLUDE = $directory/include#" "$FILE"
        sed -i "s%^  BLAS = -lopenblas\$%  BLAS = -L$directory/lib -Wl,-rpath -Wl,$directory/lib -lopenblas -lgfortran%" "$FILE"
        sed -i "s%^  LAPACK = -llapack\$%  LAPACK = -L$directory/lib -Wl,-rpath -Wl,$directory/lib -llapack%" "$FILE"
        
        make
        make install

        cd ..
        rm -rf SuiteSparse
        )

    # build numpy
    # shellcheck disable=SC2194
    case "1" in
        1)
            # This was working fine on 32 bit, but was having problems on 64 bit
            (
            cd numpy
            # This fails, but we depend on that
            cobble || true
            cd src
            cp site.cfg.example site.cfg
            #library_dirs = /home/sam/local/lib
            #include_dirs = /home/sam/local/include
            # We change all directories, rather than trying to focus on "the right" ones
            #sed -i "s%^[# ]*library_dirs = .*\$%library_dirs = $directory/lib%" site.cfg
            #sed -i "s%^[# ]*include_dirs = .*\$%include_dirs = $directory/include%" site.cfg

            # there's related stuff in site.cfg.example (now site.cfg) for uncommenting, but appending like this is easier
            (
            echo "[openblas]"
            echo "libraries = openblas"
            echo "library_dirs = $directory/lib"
            echo "include_dirs = $directory/include"
            ) >> site.cfg

            # there may be more to change in site.cfg.
            # http://www.scipy.org/scipylib/building/linux.html#building-everything-from-source-with-gfortran-on-ubuntu-nov-2010
            # ...talks about uncommenting some things that no longer appear in site.cfg.example .

            "$directory"/bin/python setup.py build
            "$directory"/bin/python setup.py install --prefix="$directory"

            cd ..
            rm -rf src
            )
            ;;
        2)
            "$directory"/bin/pip install numpy
            ;;
    esac

    # build scipy
        (
        cd scipy
        cobble || true
        cd src
        "$directory"/bin/python setup.py build
        "$directory"/bin/python setup.py install --prefix="$directory"

        cd ..
        rm -rf src
        )
    )

    case "$which_python" in
        3.[678])
            # Install tensorflow
            install_tensorflow
            ;;
    esac
}

function install_tensorflow
{
    eval "$PIP install tensorflow"
}

# intentionally not quoting $which_pythons - we need to split on whitespace
for which_python in $which_pythons
do
    set -eu
    set -o pipefail

    export which_python

    # shellcheck disable=SC2001
    which_python_sans_dash=$(echo "$which_python" | sed 's/-//')
    mkdir -p /usr/local/lib/"$which_python_sans_dash"/dist-packages/

    export which_python_sans_dash

    # -Wformat works around a bug in CPython's autoconf
    case "$(uname -m)-$which_python" in
        i686-*)
            export CFLAGS=-Wformat
            ;;
		# CPython 1.4 doesn't appear to like this.
        *-python-1.[01235]|*-python-3.[0123])
            # The older python's need to be built as a 32 bit executable.  We could port to 64 bit, but that's
            # too much of a departure from history.
			#
			# CPython 3.3 needed this on Debian 11, so I assumed 3.[012] would as well.
            export CFLAGS="-m32 -fPIC -Wformat"
            export CXXFLAGS="-m32 -fPIC"
            export CPPFLAGS="$CXXFLAGS"
            export FFLAGS="-m32 -fPIC"
            export CC="gcc -m32 -fPIC"
            export CXX="g++ -m32 -fPIC"
            export FC="gfortran -m32 -fPIC"
            ;;
        x86_64-*)
            export CFLAGS="-m64 -fPIC -Wformat"
            export CXXFLAGS="-m64 -fPIC"
            export CPPFLAGS="$CXXFLAGS"
            export FFLAGS="-m64 -fPIC"
            export CC="gcc -m64 -fPIC"
            export CXX="g++ -m64 -fPIC"
            export FC="gfortran -m64 -fPIC"
            ;;
        *)
            echo "$0: Unrecognized architecture" 1>&2
            exit 1
    esac

	case "$(uname -s)" in
		Darwin)
			i=include
			CFLAGS="$CFLAGS -I$(brew --prefix $macos_openssl)/$i -I$(brew --prefix zlib)/$i -I$(brew --prefix readline)/$i"
			CPPFLAGS="$CFLAGS"
			LDFLAGS="$CFLAGS -L$(brew --prefix $macos_openssl)/lib -L$(brew --prefix zlib)/lib -L$(brew --prefix readline)/lib"
			export CFLAGS CPPFLAGS LDFLAGS
			;;
	esac
	# This didn't help.
	# export CFLAGS="$CFLAGS -Wno-implicit-function-declaration"

    # shellcheck disable=SC2155,SC2001
    export python_dir=$(set -eu; set -o pipefail; echo "$which_python" | sed -e 's/-//')
    #export python_dir=${which_python//-/}

    # clean up the old python
    rm -rf /usr/local/c"$which_python"

    (
        # install python
        set -eu
        set -o pipefail
        cd "$python_dir"
        cobble
        'do-inst'
    )

    python3_symlink

    # symlink python3-config to python-config, if python3-config present - for making scripts nice and consistent
    if ls /usr/local/c"$which_python"/bin/python3-config > /dev/null 2>&1
    then
        (
            set -eu
            set -o pipefail
            cd /usr/local/c"$which_python"/bin
            first=python3-config
            ln -sf "$first" python-config
        )
    fi

    # This has the side-effect of setting $PIP
    install_setuptools

    install_pygments

    install_pylint

    pip_install_flake8
    pip_install_pyflakes
    pip_install_pycodestyle

    install_mypy

    install_six

    case "$which_python" in
        # python-2.[67]|python-3.[23456789])
        python-3.[3456789])
            install_cython
            ;;
    esac

    case "$do_gtk" in
        True)
            pygobject_via_pip || true
            ;;
        False)
            echo "$0: Skipping gtk by request of user" 1>&2
            ;;
        *)
            echo "$0: Invalid value of \$do_gtk: $do_gtk" 1>&2
            exit 1
            ;;
    esac

    case "$do_numerical" in
        True)
            case "$which_python" in
                python-0.*|python-1.*|python-2.[01234567]|python-3.[0123456])
                    echo "$0: Skipping numerical build because this cpython is too old" 1>&2
                    ;;
                python-3.1[12])
                    echo "$0: Skipping numerical build because this cpython is too new" 1>&2
                    ;;
                python-3.*)
                    # Actually, 3.1 appeared to build OK when I tried it, but the warning from openblas (?) says 2.6, 2.7 and >= 3.2

                    # We used to do this, but it was a big headache.  Sun Dec 10 18:24:24 PST 2017
                    # numerical_build

                    # So now, instead, we just pip install it
                    eval "$PIP install numpy scipy"
                    ;;
                *)
                    echo "$0: Unrecognized cpython version" 1>&2
                    exit 1
            esac
            ;;
        False)
            echo "$0: Skipping numerical by request of user" 1>&2
            ;;
        *)
            echo "$0: Invalid value of \$do_numerical: $do_numerical" 1>&2
            exit 1
            ;;
    esac

    # Clean up the CPython and Cython source code and temporaries - we don't need them any longer, and they're not tiny.
    # Also clean up the last-archives files - they lead to too many merge conflicts.
    case "$cleanup" in
        True)
            rm -rf "$python_dir"/src
            rm -rf cython/src
            find . -name last-archives -print0 | xargs -0 rm -f
            ;;
        False)
            ;;
        *)
            echo "$0: Internal error 2: Invalid \$cleanup: $cleanup" 1>&2
            exit 1
            ;;
    esac

done

echo
echo 'done'