#!/usr/bin/env bash

########################################################################
# Regenerate auto-generated files (e.g. configure)
#
# If the -s option is given, save the autogenerated scripts in
# $SAGE_ROOT/upstream/configure-$CONFVERSION.tar.gz where CONFVERSION
# is the sha1 of HEAD `git rev-parse HEAD`
#
# If optional argument -d is given and bootstrapping failed, instead
# extract the files from a local configure tarball, downloading it if
# needed. If -D is given, don't try to bootstrap and always extract or
# download.
#
# If optional argument -u <URL> is given download the configure
# tarball from that base url. That is, "bootstrap -u http://host/path"
# will download http://host/path/configure-$CONFVERSION.tar.gz to
# upstream/configure-$CONFVERSION.tar.gz. This is used by the buildbot
# to download tarballs that are not published.
########################################################################

# Set SAGE_ROOT to the path to this file and then cd into it
SAGE_ROOT="$(cd "$(dirname "$0")" && pwd -P)"
cd "$SAGE_ROOT"

export PATH="$SAGE_ROOT/build/bin:$PATH"

PKG=build/pkgs/configure
MAKE="${MAKE:-make}"
CONFVERSION=$(cat $PKG/package-version.txt)

install_config_rpath() {
    # The file config.rpath which comes from gettext is supposed to be
    # installed by automake, but due to a bug in most distros it is not;
    # see https://trac.sagemath.org/ticket/27823#comment:17
    #
    # Here we need to determine where gettext stores its data files and
    # copy config.rpath from there to config/
    gettextize="$(command -v gettextize)"
    if [ -z "$gettextize" ]; then
        echo >&2 "gettext and the gettextize program must be installed and be in"
        echo >&2 "your PATH. E.g. Homebrew installs them in /usr/local/opt/gettext/bin."
        return 179
    fi
    eval `sed -n '/^prefix=.*$/p' $gettextize`
    eval `sed -n '/^datarootdir=.*$/p' $gettextize`
    eval `sed -n '/^: \${gettext_datadir=.*$/p' $gettextize`

    if [ -z "$gettext_datadir" ]; then
        eval `sed -n '/^gettext_dir=.*$/p' $gettextize`
        # In older versions (before 2014) this is spelled gettext_dir
        # See https://github.com/autotools-mirror/gettext/commit/ff18897068486560e2bb421004cfbd42b7cdd0f8
        gettext_datadir="$gettext_dir"
    fi

    if [ -z "$gettext_datadir" ]; then
        echo >&2 "Failed to read the gettext_datadir directory from $gettextize"
        echo >&2 "The config.rpath file must manually be copied into config/"
        echo >&2 "This file is installed with gettext typically in /usr/share/gettext"
        return 179
    fi

    config_rpath="$gettext_datadir/config.rpath"
    if [ ! -f "$config_rpath" ]; then
        echo >&2 "Missing $config_rpath file; this indicates a broken gettext install."
        return 179
    fi

    echo "bootstrap:$LINENO: installing 'config/config.rpath'"
    cp "$config_rpath" config/
}



bootstrap () {
    rm -f m4/sage_spkg_configures.m4
    spkg_configures=""
    for filename in $(find build/pkgs -type f -name spkg-configure.m4); do
        pkgname="$(echo $filename | cut -d/ -f3)"
        echo "m4_sinclude([$filename])" >> m4/sage_spkg_configures.m4
        spkg_configures="$spkg_configures
SAGE_SPKG_CONFIGURE_$(echo ${pkgname} | tr '[a-z]' '[A-Z]')"
    done
    echo "$spkg_configures" >> m4/sage_spkg_configures.m4

    install_config_rpath && \
    aclocal -I m4 && \
    automake --add-missing --copy build/make/Makefile-auto && \
    autoconf

    st=$?
    case $st in
        0) true;; # Success

        179|16|63|127)  # install_config_rpath failed|no m4 for pkg-config|autotools not installed|or version too old
            if [ $DOWNLOAD = yes ]; then
                echo >&2 "Bootstrap failed, downloading required files instead."
                bootstrap-download || exit $?
            else
                if [ $st -eq 127 ]; then
                    verb="install"
                elif [ $st -eq 16 ]; then
                    verb="install pkg-config m4 macros for"
                else
                    verb="upgrade"
                fi
                echo >&2 "Bootstrap failed. Either $verb autotools or run bootstrap with"
                echo >&2 "the -d option to download the auto-generated files instead."
                exit $st
            fi;;

        *) exit $st;; # Failure
    esac
}

# Bootstrap by downloading the auto-generated files
bootstrap-download () {
    sage-download-file configure-$CONFVERSION.tar.gz
    if [ $? -ne 0 ]; then
        echo >&2 "Error: downloading configure-$CONFVERSION.tar.gz failed"
        exit 1
    fi

    # The "m" option to tar ensures that timestamps are set to the
    # current time, not taken from the tarball.
    # We need these files to be more recent than the input files
    # like configure.ac, otherwise "make" gets confused.
    tar xzmf $CONFBALL || exit $?
}

save () {
    set -e

    # Check that config.guess is sufficiently recent
    if ! grep '^timestamp=.*201[5-9]' config/config.guess >/dev/null; then
        echo >&2 "Error: config.guess is outdated:"
        grep >&2 '^timestamp=' config/config.guess
        echo >&2 "You should update the 'gnuconfig' or 'automake' package and try again"
        exit 63
    fi

    NEWCONFVERSION=`git rev-parse HEAD`
    NEWCONFBALL="upstream/configure-$NEWCONFVERSION.tar.gz"
    
    # Create configure tarball
    echo "Creating $NEWCONFBALL..."
    mkdir -p upstream
    tar zcf "$NEWCONFBALL" configure config/* build/make/Makefile-auto.in
    
    # Update version
    echo "$NEWCONFVERSION" >$PKG/package-version.txt
    
    # Compute checksum
    ./sage --package fix-checksum configure
}


usage () {
    echo >&2 "Usage: $0 [-d|-D|-s] [-u <URL>] [-h]"
}


# Parse options
SAVE=no
DOWNLOAD=no
ALWAYSDOWNLOAD=no
CONFTARBALL_URL=""
while getopts "Ddshu:" OPTION
do
     case "$OPTION" in
         D) ALWAYSDOWNLOAD=yes; DOWNLOAD=yes;;
         d) DOWNLOAD=yes;;
         s) SAVE=yes;;
         u) CONFTARBALL_URL="$OPTARG"; ALWAYSDOWNLOAD=yes; DOWNLOAD=yes;;
         h) usage; exit 0;;
         ?) usage; exit 2;;
     esac
done
CONFBALL="upstream/configure-$CONFVERSION.tar.gz"

if [ $DOWNLOAD$SAVE = yesyes ]; then
    echo >&2 "$0: refusing to download and save."
    usage
    exit 2
fi

# Start cleanly (it's not a problem if this fails)
$MAKE bootstrap-clean 2>/dev/null
mkdir config 2>/dev/null

# Get autotools from our own package into PATH (Trac #21214).
# If Sage has not been built yet, this will fail due to a missing
# sage-env-config. We just ignore that error.
source src/bin/sage-env 2>/dev/null


if [ $ALWAYSDOWNLOAD = yes ]; then
    if [ -n "$CONFTARBALL_URL" ]; then
        URL="$CONFTARBALL_URL"/configure-$CONFVERSION.tar.gz
        sage-download-file "$URL" upstream/configure-$CONFVERSION.tar.gz
        if [ $? -ne 0 ]; then
            echo >&2 "Error: downloading configure-$CONFVERSION.tar.gz from $CONFTARBALL_URL failed"
            exit 1
        fi
        echo >&2 "Downloaded configure-$CONFVERSION.tar.gz from $CONFTARBALL_URL "
    else
        bootstrap-download || exit $?
    fi
else
    bootstrap
fi

if [ $SAVE = yes ]; then
    save
fi
