#!/bin/bash

# Steve Redler IV <steve@sr-tech.com>
# Carl Worth <cworth@east.isi.edu>
# Robert E. Anderson <rea@sr.unh.edu>

# Modified by picons.eu

set -e

version=1.1

ipkg_extract_value() {
    sed -e "s/^[^:]*:[[:space:]]*//"
}

required_field() {
    field=$1

    value=$(grep "^$field:" < $CONTROL/control | ipkg_extract_value)
    if [[ -z $value ]]; then
        echo "*** Error: $CONTROL/control is missing field $field" >&2
        return 1
    fi
    echo $value
    return 0
}

disallowed_field() {
    field=$1

    value=$(grep "^$field:" < $CONTROL/control | ipkg_extract_value)
    if [[ -n $value ]]; then
        echo "*** Error: $CONTROL/control contains disallowed field $field" >&2
        return 1
    fi
    echo $value
    return 0
}

pkg_appears_sane() {
    local pkg_dir=$1

    local owd=$PWD
    cd $pkg_dir

    PKG_ERROR=0

    tilde_files=$(find . -name '*~')
    if [[ -n $tilde_files ]]; then
        if [[ $noclean = "1" ]]; then
            echo "*** Warning: The following files have names ending in '~'.
You probably want to remove them: " >&2
            ls -ld $tilde_files
            echo >&2
            else
            echo "*** Removing the following files: $tilde_files"
            rm -f "$tilde_files"
        fi
    fi

    large_uid_files=$(find . -uid +99 || true)

    if [[ $ogargs = "" ]]  && [[ -n $large_uid_files ]]; then
        echo "*** Warning: The following files have a UID greater than 99.
You probably want to chown these to a system user: " >&2
        ls -ld $large_uid_files
        echo >&2
    fi

    if [[ ! -f $CONTROL/control ]]; then
        echo "*** Error: Control file $pkg_dir/$CONTROL/control not found." >&2
        cd $owd
        return 1
    fi

    pkg=$(required_field Package)
    [ "$?" -ne 0 ] && PKG_ERROR=1

    version=$(required_field Version | sed 's/Version://; s/^.://g;')
    [ "$?" -ne 0 ] && PKG_ERROR=1

    arch=$(required_field Architecture)
    [ "$?" -ne 0 ] && PKG_ERROR=1

    required_field Maintainer >/dev/null
    [ "$?" -ne 0 ] && PKG_ERROR=1

    required_field Description >/dev/null
    [ "$?" -ne 0 ] && PKG_ERROR=1

    section=$(required_field Section)
    [ "$?" -ne 0 ] && PKG_ERROR=1
    if [[ -z $section ]]; then
        echo "The Section field should have one of the following values:" >&2
        echo "admin, base, comm, editors, extras, games, graphics, kernel, libs, misc, net, text, web, x11" >&2
    fi

    priority=$(required_field Priority)
    [ "$?" -ne 0 ] && PKG_ERROR=1
    if [[ -z $priority ]]; then
        echo "The Priority field should have one of the following values:" >&2
        echo "required, important, standard, optional, extra." >&2
        echo "If you don't know which priority value you should be using, then use \`optional'" >&2
    fi

    source=$(required_field Source)
    [ "$?" -ne 0 ] && PKG_ERROR=1
    if [[ -z $source ]]; then
        echo "The Source field contains the URL's or filenames of the source code and any patches"
        echo "used to build this package. Either gnu-style tarballs or Debian source packages"
        echo "are acceptable. Relative filenames may be used if they are distributed in the same"
        echo "directory as the .ipk file."
    fi

    disallowed_filename=$(disallowed_field Filename)
    [ "$?" -ne 0 ] && PKG_ERROR=1

    if echo $pkg | grep '[^a-z0-9.+-]'; then
        echo "*** Error: Package name $name contains illegal characters, (other than [a-z0-9.+-])" >&2
        PKG_ERROR=1;
    fi

    local bad_fields=$(sed -ne 's/^\([^[:space:]][^:[:space:]]\+[[:space:]]\+\)[^:].*/\1/p' < $CONTROL/control | sed -e 's/\\n//')
    if [[ -n $bad_fields ]]; then
        bad_fields=$(echo $bad_fields)
        echo "*** Error: The following fields in $CONTROL/control are missing a ':'" >&2
        echo "$bad_fields" >&2
        echo "ipkg-build: This may be due to a missing initial space for a multi-line field value" >&2
        PKG_ERROR=1
    fi

    for script in $CONTROL/preinst $CONTROL/postinst $CONTROL/prerm $CONTROL/postrm; do
        if [[ -f $script ]] && [[ ! -x $script ]]; then
            echo "*** Error: package script $script is not executable" >&2
            PKG_ERROR=1
        fi
    done

    if [[ -f $CONTROL/conffiles ]]; then
        for cf in $(cat $CONTROL/conffiles); do
            if [[ ! -f ./$cf ]]; then
                echo "*** Error: $CONTROL/conffiles mentions conffile $cf which does not exist" >&2
                PKG_ERROR=1
            fi
        done
    fi

    cd $owd
    return $PKG_ERROR
}

#######################
## ipkg-build "main" ##
#######################
ogargs=""
outer=ar
noclean=0
usage="Usage: $0 [-c] [-C] [-o owner] [-g group] <pkg_directory> [<destination_directory>]"

while getopts "cg:ho:v" opt; do
    case $opt in
        o)  owner=$OPTARG
            ogargs="--owner=$owner"
            ;;
        g)  group=$OPTARG
            ogargs="$ogargs --group=$group"
            ;;
        c)  outer=tar
            ;;
        C)  noclean=1
            ;;
        v)  echo $version
            exit 0
            ;;
        h)  echo $usage  >&2
            ;;
       \?)  echo $usage  >&2
            ;;
    esac
done

shift $(($OPTIND - 1))

# Continue on to process additional arguments

case $# in
    1)  dest_dir=$PWD
        ;;
    2)  dest_dir=$2
        if [[ $dest_dir = "." ]] || [[ $dest_dir = "./" ]]; then dest_dir=$PWD; fi
        ;;
    *)  echo $usage >&2
        exit 1
        ;;
esac

pkg_dir=$1

if [[ ! -d $pkg_dir ]]; then
    echo "*** Error: Directory $pkg_dir does not exist" >&2
    exit 1
fi

# CONTROL is second so that it takes precedence

CONTROL=""
if [[ -d $pkg_dir/DEBIAN ]]; then CONTROL="DEBIAN"; fi
if [[ -d $pkg_dir/CONTROL ]]; then CONTROL="CONTROL"; fi

if [[ -z $CONTROL ]]; then
    echo "*** Error: Directory $pkg_dir has no CONTROL subdirectory." >&2
    exit 1
fi

if ! pkg_appears_sane $pkg_dir; then
    echo >&2
    echo "ipkg-build: Please fix the above errors and try again." >&2
    exit 1
fi

tmp_dir=$dest_dir/IPKG_BUILD.$$
mkdir $tmp_dir

echo $CONTROL > $tmp_dir/tarX
( cd $pkg_dir && tar $ogargs -czf $tmp_dir/data.tar.gz -X $tmp_dir/tarX . )
( cd $pkg_dir/$CONTROL && tar $ogargs -czf $tmp_dir/control.tar.gz . )
rm $tmp_dir/tarX

echo "2.0" > $tmp_dir/debian-binary

find "$tmp_dir" -exec touch --reference="$pkg_dir/CONTROL/control" {} \;

pkg_file=$dest_dir/${pkg}_${version}_${arch}.ipk
rm -f $pkg_file
if [[ $outer = "ar" ]] ; then
    ( cd $tmp_dir && ar -crf $pkg_file ./debian-binary ./data.tar.gz ./control.tar.gz )
else
    ( cd $tmp_dir && tar $ogargs -zcf $pkg_file ./debian-binary ./data.tar.gz ./control.tar.gz )
fi

rm $tmp_dir/debian-binary $tmp_dir/data.tar.gz $tmp_dir/control.tar.gz
rmdir $tmp_dir

echo "Packaged contents of $pkg_dir into $pkg_file"