#!/bin/bash

set -u
set -e
set -o pipefail

if [ $# -lt 5 ]; then
	echo "Usage: $0 filename version arch changes_file suite"
	exit 1
fi

TARBALL="$1"	# Tarball to read, compressed with gzip
VERSION="$2"
ARCH="$3"
CHANGES="$4"	# Changes file for the upload
SUITE="$5"

error() {
	echo "$*"
	exit 1
}

# Check validity of version number
# Expected are: YYYYMMDD, YYYYMMDD.x, YYYYMMDD<suite>x, YYYYMMDD+<suite>x,
# YYYYMMDD+debXuZ and the +b[0-9] on the end
if ! echo "$VERSION" | grep -Eq "^[0-9]{8}((\.|\+?[a-z]+|\+deb[0-9]+u|\+kbsd[0-9]+u)[0-9]+)?(\+b[0-9])?$"; then
	error "Invalid version: '$VERSION'"
fi

case $SUITE in
    unstable|sid|*proposed-updates)
	: # nothing to do
	;;
    *)
	SUITE="${SUITE}-proposed-updates"
	;;
esac

# This must end with /
TARGET="/srv/ftp-master.debian.org/ftp/dists/$SUITE/main/installer-$ARCH/"

# Check validity of the target directory
# This could fail, for example for new architectures; doing
# a regular BYHAND is safer in that case
if [ ! -d "$TARGET" ]; then
	mkdir -p "$TARGET"
fi
# Check that there isn't already a directory for this version
if [ -d "$TARGET/$VERSION" ]; then
	error "Directory already exists: $TARGET/$VERSION"
fi

# We know the VERSION is sane by here, we just need to make sure we escape the + in +b1 (if any)
# It needs 'g' as well as we may have +$DIST+b[0-9] or +debXuZ+bY
VERSIONREGEXP="$(echo $VERSION | sed 's@+@\\\+@g')"

# We know all data to be in ./installer-<arch>/<version>; see if there's
# anything else in the tarball except that and the 'current' symlink
if tar tzf "$TARBALL" | \
   grep -Eqv "^\./(installer-$ARCH/($VERSIONREGEXP/.*|current|)|)$"; then
	error "Tarball contains unexpected contents"
fi

# Create a temporary directory where to store the images
umask 002
TMPDIR="$(mktemp -td byhand-di.XXXXXX)"

# If we fail somewhere, cleanup the temporary directory
cleanup() {
        rm -rf "$TMPDIR"
}
trap cleanup EXIT

# Extract the data into the temporary directory
tar xzf "$TARBALL" --directory="$TMPDIR" "./installer-$ARCH/"

# Check the 'current' symlink
if [ ! -L $TMPDIR/installer-$ARCH/current ]; then
	error "Missing 'current' symlink"
elif [ X"$(readlink "$TMPDIR/installer-$ARCH/current")" != X"$VERSION" ]; then
	error "Incorrect 'current' symlink"
fi

# We should have an MD5SUMS file; use that for a final check
if [ -r "$TMPDIR/installer-$ARCH/$VERSION/images/MD5SUMS" ]; then
	(
		cd "$TMPDIR/installer-$ARCH/$VERSION/images"
		md5sum -c --status MD5SUMS || error "Error while checking MD5SUMS"
	)
else
	error "Missing MD5SUMS file"
fi

# Move the data to the final location
mv "$TMPDIR/installer-$ARCH/$VERSION" "$TARGET"
mv "$TMPDIR/installer-$ARCH/current"  "$TARGET"

# Fixup permissions
find "$TARGET/$VERSION" -type d -exec chmod 755 {} +
find "$TARGET/$VERSION" -type f -exec chmod 644 {} +

# Make sure nothing symlinks outside of the ftpdir
# Shouldnt happen, but better be sure.
symlinks -d -r /srv/ftp-master.debian.org/ftp

trap - EXIT
cleanup

exit 0