#!/bin/bash

set -e
shopt -s extglob

# Set defaults from the running kernel
arch="$(dpkg --print-architecture)"
kernelabi="$(uname -r)"
ff="${kernelabi#+([^-])-@(trunk|+([0-9]))-}"
if [ "x$ff" != "x$kernelabi" ]; then
    flavour="${ff#@(openvz|vserver|xen)-}"
    if [ "x$flavour" != "x$ff" ]; then
	featureset="${ff%-$flavour}"
    else
	featureset=none
    fi
else
    flavour=
    featureset=none
fi

eval "set -- $(getopt -n "$0" -- "f:j:s:" "$@")"
while true; do
    case "$1" in
	-f) flavour="$2"; shift 2 ;;
	-j) export DEBIAN_KERNEL_JOBS="$2"; shift 2 ;;
	-s) featureset="$2"; shift 2 ;;
	--) shift 1; break ;;
    esac
done
	    
if [ $# -lt 1 ]; then
    echo >&2 "Usage: $0 [<options>] <patch>..."
    cat >&2 <<EOF
Options:
     -f <flavour>     specify the 'flavour' of kernel to build, e.g. 686
     -j <jobs>        specify number of compiler jobs to run in parallel
     -s <featureset>  specify an optional featureset to apply, e.g. xen
EOF
    exit 2
fi

if [ -z "$flavour" ]; then
    echo >&2 "You must specify a flavour to build with the -f option"
    exit 2
fi

dpkg-checkbuilddeps -B

# Append 'a~test' to Debian version; this should be less than any official
# successor and easily recognisable
version="$(dpkg-parsechangelog | sed 's/^Version: //; t; d')"
if [ "${version%a~test}" = "$version" ]; then
    version="$version"a~test
    dch -v "$version" --distribution UNRELEASED "Testing patches $*"
fi

restrictfeature=
series="${version##*-}"
if [ "$featureset" != none ]; then
    restrictfeature=" featureset=$featureset"
    series="${series}-extra"
fi

# Copy all patches into a new directory
rm -rf debian/patches/test/
mkdir debian/patches/test
cp -t debian/patches/test/ "$@"

# Generate patch series for the new version
>debian/patches/series/"$series"
for patch in "$@"; do
    echo "+ test/$(basename "$patch")${restrictfeature}" >>debian/patches/series/"$series"
done

# Regenerate control and included rules
rm debian/control debian/rules.gen
debian/rules debian/control-real && exit 1 || true
test -f debian/control
test -f debian/rules.gen

# Clean and patch source
debian/rules clean
debian/rules source

# Build selected binaries
fakeroot make -f debian/rules.gen binary-arch_"$arch"_"$featureset"_"$flavour"