#!/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
}

[ $# -gt 0 ] && fatal "This is not an autoconf script. Run it without any options and you will be prompted."

ask ()
{
   local A D

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

   echo -n "$BLACK$BOLD::$SGR0 $1 [$BOLD${D}$SGR0] "
   read A
   A=${A:-$D}

   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 $?
}

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
    ok
}

begin_options ()
{
    # get the old values
    extract_options

    echo > make.conf
    append "# This file was automatically generated on `date`. Any changes may be lost!"
    append "## options"

    echo "--- Configuration required ---"
}

begin_tests ()
{
    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 ()
{
    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

    append "${1}_LIBS=`pkg-config --libs $3`"
    append "${1}_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`"
}