#!/bin/bash
# Build a packaged crate.
#
# This script is not run directly, but linked into ./build/ when running one of
# the other scripts, so you should do that instead of running this directly.
#
# Usage: [REALVER=<EXACTVER>] ./build.sh <CRATE> [<SEMVER>] [<EXTRA DEPENDENCY DEB> ...]
#
# Envvars:
# IGNORE_MISSING_BUILD_DEPS=1
#     Don't abort on missing build deps. You'll need
#     this when giving extra dependency debs.
# DISTRIBUTION=$suite
#     Release to something other than unstable, e.g. experimental
# CHROOT=$chroot
#     Build using another schroot than debcargo-unstable-amd64-sbuild
set -e

SCRIPTDIR="$(dirname $(readlink -f "$0"))"

abort() { local x=$1; shift; for i in "$@"; do echo >&2 "$0: abort: $i"; done; exit "$x"; }
report() { for i in "$@"; do echo >&2 "debcargo-conf builder: $i"; done; }

if [ "$(basename "$PWD")" != "build" ]; then
	abort 1 "This script is only meant to be run from the build/ directory."
fi

if [ -n "$DEBCARGO" ]; then
	true
elif which debcargo >/dev/null; then
	DEBCARGO=$(which debcargo)
elif [ -f "$HOME/.cargo/bin/debcargo" ]; then
	DEBCARGO="$HOME/.cargo/bin/debcargo"
else
	abort 1 "debcargo not found, run \`cargo install debcargo\` or set DEBCARGO to point to it"
fi

CRATE="$1"
VER="$2"
if test -z "$VER" -o -f "$VER"; then
	VER=""
	shift
else
	shift 2
fi
DISTRIBUTION="${DISTRIBUTION:-unstable}"

PKGNAME=$($DEBCARGO deb-src-name "$CRATE" $VER || abort 1 "couldn't find crate $CRATE")
DEBVER=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SVersion)
DEBSRC=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SSource)
DEBDIST=$(dpkg-parsechangelog -l $PKGNAME/debian/changelog -SDistribution)
DEB_HOST_ARCH=$(dpkg-architecture -q DEB_HOST_ARCH)
SRCNAME="${DEBSRC}_${DEBVER}"
BUILDNAME="${DEBSRC}_${DEBVER}_${DEB_HOST_ARCH}"
if [ -z "$CHROOT" ]; then
	if schroot -i -c "debcargo-unstable-${DEB_HOST_ARCH}-sbuild" >/dev/null 2>&1; then
		CHROOT="debcargo-unstable-${DEB_HOST_ARCH}-sbuild"
	elif schroot -i -c "unstable-${DEB_HOST_ARCH}-sbuild" >/dev/null 2>&1; then
		CHROOT="unstable-${DEB_HOST_ARCH}-sbuild"
		echo >&2 "Automatically using sbuild chroot unstable-${DEB_HOST_ARCH}-sbuild; however it's"
		echo >&2 "strongly recommended to create a separate chroot debcargo-unstable-${DEB_HOST_ARCH}-sbuild"
		echo >&2 "so your builds won't have to re-download & re-install cargo, rustc, and llvm every time."
		echo >&2 "See README.rst section \"Build environment\" for details."
		sleep 1
	elif [ "$SOURCEONLY" != 1 ]; then
		abort 1 "could not automatically find a suitable chroot; set CHROOT"
	fi
fi

shouldbuild() {
	local dst="$1"
	local src="$2"
	test ! -e "$dst" -o "$src" -nt "$dst"
}

if shouldbuild "$SRCNAME.dsc" "$PKGNAME/debian/changelog" ]; then
	if [ "$REUSE_EXISTING_ORIG_TARBALL" = 1 ]; then
		UPSVER="${DEBVER%-*}"
		mv "${DEBSRC}_${UPSVER}.orig.tar.gz" "${DEBSRC}_${UPSVER}.orig.tar.gz.new"
		apt-get -t unstable source --download-only "${DEBSRC}" # "=${DEBVER}"
		# check that old tarball contains same contents as new tarball
		if ! diff -ru \
			  --label "${DEBSRC}_${UPSVER}.orig.tar.gz.new" \
			  <(zcat  "${DEBSRC}_${UPSVER}.orig.tar.gz.new" | tar -tvvf-) \
			  --label "${DEBSRC}_${UPSVER}.orig.tar.gz" \
			  <(zcat  "${DEBSRC}_${UPSVER}.orig.tar.gz" | tar -tvvf-); then
			read -p "contents differ, continue with old tarball or abort? [y/N] " x
			if [ "$x" != "y" ]; then exit 1; fi
		fi
		# extract old tarball into new directory, to avoid "modified files" problems with dpkg-source later
		( cd "$PKGNAME" && dpkg-source --after-build . && tar --strip-components=1 -xf "../${DEBSRC}_${UPSVER}.orig.tar.gz" )
	fi
	( cd "$PKGNAME" && dpkg-buildpackage -d -S --no-sign )
	# sign if not UNRELEASED
	if echo "$DEBDIST" | grep -qv UNRELEASED-FIXME-AUTOGENERATED-DEBCARGO; then
		debsign "${SRCNAME}_source.changes"
	fi
fi

EXTRA_DEBS=( "$@" )

check_build_deps() {
	mkdir -p dpkg-dummy
	if shouldbuild dpkg-dummy/status /var/cache/apt/pkgcache.bin; then
		# pretend dpkg status file that marks all packages as installed
		# this is because dpkg-checkbuilddeps only works on installed pkgs
		( apt-cache dumpavail -o APT::Default-Release=unstable && \
			for i in ${EXTRA_DEBS[*]}; do apt-cache show $(echo $i | cut -d_ -f1); done ) | \
		sed -e 's/Package: .*/\0\nStatus: install ok installed/g' > dpkg-dummy/status
		if ! test -s dpkg-dummy/status; then
			abort 1 "couldn't generate dpkg-dummy/status, is Debian unstable in your APT sources?"
		fi
	fi
	( cd "$PKGNAME" && dpkg-checkbuilddeps --admindir=../dpkg-dummy )
}

if ! check_build_deps; then
	if [ "$IGNORE_MISSING_BUILD_DEPS" != 1 ]; then
		abort 1 "Missing build-dependencies, but maybe try '{apt,cargo} update'"
	fi
fi

if [ "$SOURCEONLY" = 1 ]; then
	exit
fi

if [ -n "${EXTRA_DEBS[*]}" ]; then
    EXTRA_DEBS_SBUILD=("${EXTRA_DEBS[@]/#/--extra-package=}")
    EXTRA_DEBS_REPO_TMP=$(mktemp -d "${SRCNAME}_REPO_XXXXXXXX")
    # trap cleans up even if user does Ctrl-C
    # https://stackoverflow.com/a/14812383 inside "trap" avoids running handler twice
    trap 'excode=$?; rm -rf "'"$EXTRA_DEBS_REPO_TMP"'"; trap - EXIT' EXIT HUP INT QUIT PIPE TERM
    # symlinks don't work here
    ln -f "${EXTRA_DEBS[@]}" "$EXTRA_DEBS_REPO_TMP/"
    ( cd "$EXTRA_DEBS_REPO_TMP"; apt-ftparchive packages . > Packages )
    EXTRA_DEBS_AUTOPKGTEST_OPTS=([0]=--autopkgtest-opt=--copy="$PWD/$EXTRA_DEBS_REPO_TMP/:/tmp/$EXTRA_DEBS_REPO_TMP/" [1]=--autopkgtest-opt=--add-apt-source="deb [trusted=yes] file:///tmp/$EXTRA_DEBS_REPO_TMP ./")
fi

AUTOPKGTEST_OPTS=("--run-autopkgtest" "--autopkgtest-root-arg=" "--autopkgtest-opts=-- schroot ${CHROOT}")
if [ "$SKIP_AUTOPKGTEST" = 1 ]; then
	AUTOPKGTEST_OPTS=()
	EXTRA_DEBS_AUTOPKGTEST_OPTS=()
fi

LINTIAN_OPTS=()
if echo "$DEBDIST" | grep -q UNRELEASED-FIXME-AUTOGENERATED-DEBCARGO; then
	LINTIAN_OPTS=([0]="--lintian-opt=--suppress-tags" [1]="--lintian-opt=bad-distribution-in-changes-file")
fi

SBUILD_CONFIG="$SCRIPTDIR/dev/sbuildrc" sbuild --no-source --arch-any --arch-all \
  ${CHROOT:+-c $CHROOT} \
  ${DISTRIBUTION:+-d $DISTRIBUTION} \
  "${EXTRA_DEBS_SBUILD[@]}" \
  "${EXTRA_DEBS_AUTOPKGTEST_OPTS[@]}" \
  "${AUTOPKGTEST_OPTS[@]}" \
  "${LINTIAN_OPTS[@]}" \
  "$SRCNAME.dsc"
if [ "$SKIP_AUTOPKGTEST" != 1 ]; then
	report "analyzing autopkgtest log: $BUILDNAME.test.log"
	# this is a bit of a hack but works OK for now, until sbuild supports %SBUILD_BUILD_DIR in --autopkgtest-opt
	sed -ne '/autopkgtest .*: testing package .* version .*/,$p' "$BUILDNAME.build" > "$BUILDNAME.test.log"
	"$SCRIPTDIR/dev/rust-regressions.sh" "$BUILDNAME.test.log"
fi

changestool "$BUILDNAME.changes" adddsc "$SRCNAME.dsc"
report "build complete: $BUILDNAME.changes"

# sign if not UNRELEASED
if echo "$DEBDIST" | grep -qv UNRELEASED-FIXME-AUTOGENERATED-DEBCARGO; then
	debsign ${DEBSIGN_KEYID:+-k $DEBSIGN_KEYID }--no-re-sign "$BUILDNAME.changes"
fi