#!/bin/bash
# Based on the method described here:
# http://troubleshootingrange.blogspot.com/2012/09/hosting-simple-apt-repository-on-centos.html
# Please install 'dpkg' and 'dpkg-devel' packages before use.

set -e

ARCH=amd64
REPO_PATH=$1
SUITE=$2
SECTION=main

BINDIR=${REPO_PATH}/dists/${SUITE}/${SECTION}

# Validate structure of the repo
mkdir -p "${BINDIR}/binary-${ARCH}/"
mkdir -p "${REPO_PATH}/pool/${SECTION}"
RELEASE="${REPO_PATH}/dists/${SUITE}/Release"
touch ${RELEASE}

release_header=`sed '/MD5Sum:/,$d' ${RELEASE}`

override_main="indices/override.${SUITE}.${SECTION}"
override_udeb="indices/override.${SUITE}.${SECTION}.debian-installer"
override_extra="indices/override.${SUITE}.extra.${SECTION}"

if [ -f "${REPO_PATH}/${override_main}" ]; then
    binoverride="${override_main}"
else
    binoverride=""
fi
if [ -f "${REPO_PATH}/${override_udeb}" ]; then
    binoverride_udeb="${override_udeb}"
else
    binoverride_udeb=""
fi
if [ -f "${REPO_PATH}/${override_extra}" ]; then
    extraoverride="--extra-override ${override_extra}"
else
    extraoverride=""
fi

package_deb=${BINDIR}/binary-${ARCH}/Packages
package_udeb=${BINDIR}/debian-installer/binary-${ARCH}/Packages

cd ${REPO_PATH}

# Scan *.deb packages
dpkg-scanpackages  -m ${extraoverride} -a ${ARCH} pool/${SECTION} ${binoverride} > ${package_deb}.tmp 2>/dev/null

gzip -9c ${package_deb}.tmp > ${package_deb}.gz.tmp
bzip2 -ckz ${package_deb}.tmp > ${package_deb}.bz2.tmp

# Replace original files with new ones
mv --backup -f ${package_deb}.tmp ${package_deb}
mv --backup -f ${package_deb}.gz.tmp ${package_deb}.gz
mv --backup -f ${package_deb}.bz2.tmp ${package_deb}.bz2

# Scan *.udeb packages
if [ -d "${BINDIR}/debian-installer/binary-${ARCH}/" ]; then
    dpkg-scanpackages --udeb -m -a ${ARCH} pool/debian-installer ${binoverride_udeb}  > ${package_udeb}.tmp 2>/dev/null

    gzip -9c ${package_udeb}.tmp > ${package_udeb}.gz.tmp
    bzip2 -ckz ${package_udeb}.tmp > ${package_udeb}.bz2.tmp

    # Replace original files with new ones
    mv --backup -f ${package_udeb}.tmp ${package_udeb}
    mv --backup -f ${package_udeb}.gz.tmp ${package_udeb}.gz
    mv --backup -f ${package_udeb}.bz2.tmp ${package_udeb}.bz2
fi

# Generate release file
cd ${REPO_PATH}/dists/${SUITE}
echo "$release_header" > Release.tmp

# Generate hashes
c1=(MD5Sum: SHA1: SHA256: SHA512:)
c2=(md5 sha1 sha256 sha512)

i=0
while [ $i -lt ${#c1[*]} ]; do
    echo ${c1[i]}
        for hashme in `find ${SECTION} -type f \( -not -name "*~" -name "Package*" -o -name "Release*" \)`; do
        ohash=`openssl dgst -${c2[$i]} ${hashme}`
        chash="${ohash##* }"
        size=`stat -c %s ${hashme}`
        echo " ${chash} ${size} ${hashme}"
    done
    i=$(( $i + 1));
done >> Release.tmp

mv --backup -f Release.tmp Release