#!/bin/bash
# debian/repack - Produce DFSG compliant orig.tar.xz from upstream tarball.
#  1) Unpack upstream tarball.
#  2) Check for DSFG compliance (no PDFs, SF3s or precompiled binaries).
#  3) Set revision number in mscore/revision.h to match Git commit number.
#  4) Pack into orig.tar.xz

set -e # exit on error

watchfile=$(dirname "$0")/watch
if [[ ! -e $watchfile ]]; then
  printf >&2 '%s: Error! File %s not found.\n' "$0" "$watchfile"
  exit 1
fi
apipath=$(grep -o '\<https://api.github.com/[^ \n]*' "$watchfile")
if [[ -z $apipath ]]; then
  printf >&2 '%s: Error! github.com repository not found in %s!\n' "$0" "$watchfile"
  exit 1
fi

function usage() {
cat >&2 <<EOF
debian/repack - set MuseScore revision number and check for DFSG compliance.

Usage:    debian/repack  --upstream-version  VERSION  [UPSTREAM-TARBALL]
Example:  debian/repack  --upstream-version  "2.0.1+dfsg1"
EOF
}

if [[ $1 = --usage || $1 = --help || $1 = -[h?] ]]; then
  usage
  exit 0
fi

if [[ $1 != --upstream-version || -z $2 ]]; then
  printf >&2 '%s: Error! Upstream version was not specified.\n\n' "$0"
  usage
  exit 1
fi

baseversion=$2
debversion=${baseversion//'%'/'~'}
if [[ $baseversion = *'+dfsg'* ]]; then
  baseversion=${baseversion%+dfsg*}
fi
gitversion=v${baseversion//'~'/'%'}
baseversion=${baseversion//'%'/'~'}

printf >&2 'D: baseversion<%s> debversion<%s> gitversion<%s>\n' \
  "$baseversion" "$debversion" "$gitversion"

tarpath=${3:-../musescore3_$2.orig.tar.gz}
printf >&2 '%s\n' "$0: Repacking upstream tarball '$tarpath'."

if [[ ! -f $tarpath ]]; then
  printf >&2 '%s: Error! Upstream tarball not found.\n\n' "$0"
  usage
  exit 1
fi

tarball="$(basename "$tarpath")"
outdir="$(dirname "$tarpath")" # send output files to input directory

if [[ -n $(which realpath) ]]; then
  outdir="$(realpath --relative-to="$PWD" "$outdir")"
fi

cd "$outdir"

symlink=""
if [[ -L $tarball ]]; then
  # If $tarball was actually a symlink then resolve it
  symlink="$tarball"
  tarball="$(readlink "$symlink")"
fi

tempdir="tmp-musescore-$debversion"

# 1) Unpack upstream tarball
printf >&2 '%s\n' "Unpacking upstream tarball into '$tempdir'."
rm -rf "$tempdir"
mkdir "$tempdir"
tar -xaf "$tarball" -C "$tempdir"
cd "$tempdir"
mv *use*ore* "musescore3-$debversion.orig"
cd "musescore3-$debversion.orig"

# 2) Check for DSFG compliance (no precompiled binaries or PDFs, etc).
cat >&2 <<EOF
Checking for DFSG compliance. If any non compliant files are discovered then
they will be printed on the Terminal and then this script will exit. The non-
compliant files must be added to the Files-Excluded list within debian/copyright
and then you will need to run 'uscan' again. See uscan(1).
EOF

dfsg_compliant="TRUE"

echo >&2 "Searching for PDF, SF3 and object files..."
pdfs=$(find . -iname \*.pdf -o -iname \*.sf3 -o -iname \*.dll -o \
    -iname \*.o -o -iname \*.a -o -iname \*.so -o -iname \*.so.\*)
if [[ -n $pdfs ]]; then
  printf >&2 '%s\n' \
   "$pdfs" \
   "PDF, SF3 or other object files, which are not DFSG-free, were discovered." \
   "Please add them to Files-Excluded in debian/copyright."
  dfsg_compliant="FALSE"
fi

echo >&2 "Searching for precompiled binaries..."
binaries="$(find . -type f -executable -exec sh -c "file -i '{}' | grep -q 'x-executable; charset=binary'" \; -print)"
if [[ -n $binaries ]]; then
  printf >&2 '%s\n' \
   "$binaries" \
   "Binary files were discovered. Binaries are non DFSG-free." \
   "Please add them to Files-Excluded in debian/copyright."
  dfsg_compliant="FALSE"
fi

if [[ $dfsg_compliant != TRUE ]]; then
  echo >&2 "You will need to run 'uscan' again afterwards."
  exit 1
fi

# 3) Set revision number in mscore/revision.h to match upstream Git commit
# Note: upstream has a Makefile target "make revision" to set the revision, but
# it only works inside a Git repo so we have to get the revision another way.
echo >&2 "Determining upstream revision (first 7 characters of Git commit SHA)."

if ! apires=$(wget -S --content-on-error -O - "$apipath"); then
  printf >&2 '%s: Error! Could not read from GitHub API:\n%s\n' "$0" "$apires"
  exit 1
fi

commit="$( \
  printf '%s\n' "$apires" \
   | tr -d '[:space:]' | sed -r 's/("name":)/\n\1/g' \
   | grep -F "\"name\":\"$gitversion\"" \
   | sed -nr 's/.*"sha":"([[:alnum:]]{7})[[:alnum:]]{33}".*/\1\n/p' \
)"

if [[ -z $commit ]]; then
  printf >&2 '%s: Error! Could not get upstream commit. Data:\n%s\n' "$0" "$apires"
  exit 1
fi

printf >&2 '%s\n' "Upstream revision is '$commit'."

printf >&2 '%s\n' "Setting revision number in 'mscore/revision.h' to '$commit'."
mtime="$(stat -c %y "mscore/revision.h")" # preserve modification time
printf '%s\n' "$commit" >"mscore/revision.h"
touch -d "$mtime" "mscore/revision.h"

# 4) Pack into orig.tar.xz
cd .. # now inside $tempdir
printf >&2 '%s\n' "Creating musescore3_$debversion.orig.tar; this may take a while"
tar -cf "../musescore3_$debversion.orig.tar" \
    -Hustar -b1 \
    --numeric-owner --owner=0 --group=0 \
    --mode='u=rwX,go=rX' \
    "musescore3-$debversion.orig"
cd .. # now back to output directory (outside $tempdir)

# Tidy up (must do this before compressing tar incase tarball has same name)
echo >&2 "Removing temporary files."
rm -rf "$tempdir" "$tarball" "$symlink"

# Compress new orig.tar
printf >&2 '%s\n' "Compressing musescore3_$debversion.orig.tar; this will take long"
xz -7e "musescore3_$debversion.orig.tar"

cat >&2 <<EOF
Finished!
The upstream code is in "$outdir/musescore3_$debversion.orig.tar.xz".
Check this in with pristine-tar after committing it to the upstream-stable branch:
 \$ pristine-tar commit '$outdir/musescore3_$debversion.orig.tar.xz' upstream-stable
Then tag the upstream-stable branch and merge it into master.
EOF