#!/bin/sh
#
# Copyright (C) 2008 Jonathan Moore Liles
# This file is licensed under version 2 of the GPL.

. scripts/colors

# support functions for 'configure' scripts.


fatal ()
{
    echo "$BOLD$RED$*$SGR0" > /dev/stderr
    exit 255
}

UPDATE=no
HELP=no

split ()
{
    while [ $# -gt 0 ]
    do
        echo $1
        shift 1
    done
}

if [ $# -gt 0 ]
then
    case "$1" in
        --update)
            UPDATE=yes
            shift 1
            ;;
        --help)
            HELP=yes
            shift 1
            ;;
        *)
#            fatal "This is not an autoconf script. Run it without any options and you will be prompted."
            ;;
    esac

    if [ $# -gt 0 ]
    then
        echo "## options" > make.conf

        split "$@" | sed '
s/--\(enable\|disable\)-\([^ =]\+\)/--\1-\U\2/g;
s/--enable-\([^ =]\+\)=\(.*\)/USE_\1=\2/g;
s/--enable-\([^ =]\+\)/USE_\1=yes/g;
s/--disable-\([^ =]\+\)/USE_\1=no/g;
s/--\([^ =]\+\)/\1/g;
' | sed -n '/^[^ =]\+=./p' >> make.conf
        UPDATE=yes;
    fi
fi

ask ()
{
    local A D O

    D="`eval echo \\$$2`"
    D=${D:-$3}

    if [ $HELP = yes ]
    then
        if [ "$3" = yes ] || [ "$3" = no ]
        then
            O=`echo -n "$2" | sed s/^USE_/--enable-/ | tr '[[:upper:]]' '[[:lower:]]'`
        else
            O=`echo -n "--$2" | tr '[[:upper:]]' '[[:lower:]]'`
        fi

        printf "    ${BOLD}${GREEN}%-15s${SGR0}\t%-40s (currently: ${BOLD}%s${SGR0})\n" "$O" "$1" "$D"

        return
    fi

    echo -n "$BLACK$BOLD::$SGR0 ${1}? [$BOLD${D}$SGR0] "

    if [ $UPDATE = yes ]
    then
        A="$D"
        echo
    else
        read A
        A=${A:-$D}
    fi

    if [ "$3" = yes ] || [ "$3" = no ]
    then
        case "$A" in
            no | n | N) A=no ;;
            yes | y | Y) A=yes ;;
            * ) fatal "Invalid response. Must be 'yes' or 'no'" ;;
        esac
    fi

    append "${2}=${A:-$D}"
}

ok ()
{
    echo "$BOLD${GREEN}ok${SGR0}"
}

failed ()
{
    echo "$BOLD${RED}failed!${SGR0}" > /dev/stderr
    rm -f make.conf
}

using ()
{
    [ "`eval echo \\$USE_$1`" = yes ]

    return $?
}

upcase ()
{
    echo "$*" | tr '[[:lower:]]' '[[:upper:]]'
}

extract_options ()
{
    local line name value

    if [ -f make.conf ]
    then
        {
            while read line
            do
                [ "$line" = "## options" ] && break
            done

            while read line
            do
                if [ "$line" = "## libs" ]
                then
                    break
                else
                    name=${line%=*}
                    value=${line#*=}
                    eval "$name='$value'"
                fi
            done
        } < make.conf
    fi
}

begin ()
{
    echo -n "Checking sanity..."
    require_command pkg-config pkg-config > /dev/null
    require_command sed sed > /dev/null
    ok
}

warn ()
{
    echo " ${BOLD}${YELLOW}* ${SGR0}$*"
}

begin_options ()
{
    # get the old values
    extract_options

    if [ $HELP = yes ]
    then
        echo
        warn "This is not an autoconf script! Run without any arguments and you will be prompted."
        warn "Alternatively, you may use the following autoconf style arguments for"
        warn "non-interactive configuration."
        echo
        echo " Available options:"
        echo
    else
        echo > make.conf
        append "# This file was automatically generated on `date`. Any changes may be lost!"
        append "## options"

        if [ $UPDATE = yes ]
        then
            echo "--- Updating configuration ---"
        else
            echo "--- Configuration required ---"
        fi
    fi
}

begin_tests ()
{
    [ $HELP = yes ] && exit 0

    append "## libs"
    extract_options
}

append ()
{
    echo "$1" >> make.conf
}

end ()
{
    echo "--- Configuration complete ---"
    touch make.conf
}

require_command ()
{
    echo -n "Checking for ${BOLD}$1${SGR0}..."

    if ! [ -x "`which $2`" ]
    then
	failed
	fatal "Command $1 not found."
    else
	ok
    fi
}

require_package ()
{
    local name

    echo -n "Checking for $BOLD$1$SGR0..."
    if ! pkg-config --exists $3
    then
    	failed
	fatal "Required package $1 doesn't appear to be installed."
    elif ! pkg-config --atleast-version $2 $3
    then
        failed
        fatal "The installed version of $1 (`pkg-config --mod-version $3`) is too old."
    fi

    name="`upcase \"$1\"`"
    append "${name}_LIBS=`pkg-config --libs $3`"
    append "${name}_CFLAGS=-DHAVE_${1} `pkg-config --cflags $3`"

    ok
    return 0
}

_test_version ()
{
    [ $1 $4 $5 ] && [ $2 $4 $6 ] && [ $3 $4 $7 ]
}

test_version ()
{
    local IFS
    IFS='.'

    if  [ $2 != -ge ] && [ $2 != -le ]
    then
        fatal "Syntax error"
    fi

    _test_version $1 $2 $3
}

version_of ()
{
    echo `pkg-config --modversion $1`
}

require_FLTK ()
{
    local use

    echo -n "Checking for ${BOLD}FLTK${SGR0}..."

    FLTK_VERSION=`fltk-config --version`

    if ! test_version $FLTK_VERSION -ge $1
    then
        failed
        fatal "The installed FLTK version ($FLTK_VERSION) is too old."
    else
        ok
    fi

    use=

    while [ $# -gt 1 ]
    do
        shift 1
        use="$use --use-$1"
    done

    append "FLTK_LIBS=`fltk-config $use --ldflags`"
    append "FLTK_CFLAGS=`fltk-config $use --cflags`"
}