#!/bin/bash
set -e
set -x

if [ -z $1 ] || [ $1 == "--help" ] || [ $1 == "-h" ]
then cat <<EOF
usage : packager VERSION [BRANCH] [TAG]"
- VERSION is the version number of the package to create, we expect
    there is a tag named mathcomp-\$VERSION which archive we can
    download from github
- BRANCH is the name of a branch where we can find accurate local opam
    files. Actually, this may only matter for the Coq version dependencies
    located in the ssreflect package. Default value is "mathcomp-\$VERSION"
- TAG is the name of the tag used to build the archive, this is
    particularily useful for generating the package for the odd order
    theorem if we want to keep it separate from the rest of mathcomp
    e.g. "packager 1.6.1 mathcomp-odd-order.1.6.1 mathcomp-odd-order.1.6.1"
    Default value is "mathcomp-\$VERSION"
EOF
     exit 0
else
VERSION=$1
fi

if [ -z $2 ]
then BRANCH="mathcomp-$VERSION"
else BRANCH=$2
fi
# verify whether $BRANCH exists
git rev-parse --verify $BRANCH

if [ -z $3 ]
then TAG="mathcomp-$VERSION"
else TAG=$3
fi
# verify whether $TAG exists
git rev-parse --verify $TAG

ARCHIVEURL="http://github.com/math-comp/math-comp/archive/$TAG.tar.gz"

# we build the url file content and the list of packages, and where to put them
if [ $VERSION == "dev" ]
then
# variables useful for package construction
  URLLINE="git: \"https://github.com/math-comp/math-comp.git\""
  PKGS=$(sed -r "s/.*mathcomp\.([^\.]*)*.*/\1/" $(git root)/mathcomp/all/all.v \
        | paste -sd " " -)
  PKGPREFIX="$(git root)/opam/extra-dev/packages"
else
  ARCHIVE=$(mktemp)
  git archive --format=tgz --output=$ARCHIVE \
      --prefix=math-comp-$TAG/ $TAG # reproduce github archive
  SUM=$(md5sum $ARCHIVE | cut -d " " -f 1)
  EXTRACTED=$(mktemp -d)
  tar -C $EXTRACTED -zxvf $ARCHIVE
# variables useful for package construction
  URLLINE="http: \"$ARCHIVEURL\""
  CHECKSUMLINE="checksum: \"$SUM\""
  PKGS=$(ls -fs -d -1 $EXTRACTED/*/mathcomp/*/opam \
        | sed -r "s?.*mathcomp/([^/]+)/opam?\1?" \
        | paste -sd " " -)
  PKGPREFIX="$(git root)/opam/released/packages"
fi

# for each package, we pick the corresponding opam and descr file and
# rewrite them to adapt them to single package construction and
# version numbers
for pkg in $PKGS
do pkgdir="$PKGPREFIX/coq-mathcomp-$pkg/coq-mathcomp-$pkg.$VERSION"
   mkdir -p $pkgdir
   if [ $VERSION == "dev" ]
   then cp $(git root)/mathcomp/$pkg/opam $pkgdir/opam
        cp $(git root)/mathcomp/$pkg/descr $pkgdir/descr
   else git show "$BRANCH:mathcomp/$pkg/opam" > $pkgdir/opam
	git show "$BRANCH:mathcomp/$pkg/descr" > $pkgdir/descr
        sed -r "/^version/s?dev?$VERSION?" -i $pkgdir/opam
        sed -r "/^depends.*coq-mathcomp.*/s?dev?$VERSION?" -i $pkgdir/opam
   fi
   sed -r "/^(build|install)/s?make?make \"-C\" \"mathcomp/$pkg\"?" -i $pkgdir/opam
   echo $URLLINE > $pkgdir/url
   if [ $VERSION != "dev" ]
   then echo $CHECKSUMLINE >> $pkgdir/url
   fi
done

# finally test the existence of the archive
wget --spider $ARCHIVEURL