#!/bin/sh
#
# Copyright © 2006-2009 Jonas Smedegaard <dr@jones.dk>
# Description: Create QEMU environment
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
# 02111-1307 USA.
#
# Depends: qemu, sudo

set -e

PRG=$(basename "$0")

showhelp() {
	cat <<EOF
Usage:   $PRG POOL [ DISTRIBUTION [ OTHERMIRROR] ]

Examples:
    $PRG sid
    $PRG sid+mm sid 'deb http://debian-multimedia.org/ sid main'
    $PRG sid-ia32 sid --arch i386
EOF
}

exit1() {
	echo "ERROR: $1"
	exit 1
}

ask() {
	echo -n "$1 (y/N)? "
	read response
	case "$response" in
	    y|Y)
		:
		;;
	    *)
		return 1
		;;
	esac
	return
}

if [ $# -eq 0 ]; then
	showhelp
	exit1 "not enough parameters"
fi

pool=
distro=
arch=
newline='
'
while [ $# -gt 0 ]; do
	case $1 in
		-h|--help)
			showhelp
			exit 0
			;;
		--arch|-a)
			arch="$2"
			shift 2 || exit1 "option \"--arg\" requires an argument"
			;;
		--)
			shift
			break
			;;
		--*|-*)
#			opts="$opts $1"
#			shift
			exit1 "options (apart from --arch) are curently unsupported"
			;;
		*)
			if [ -z "$pool" ]; then
				pool="$1"
			elif [ -z "$distro" ]; then
				distro="$1"
			else
				othermirrors="${othermirrors:+$othermirrors$newline}$1"
			fi
			shift
			;;
	esac
done

if [ -z "$pool" ]; then
	exit1 "no pool provided"
fi
if [ -z "$distro" ]; then
	distro="$pool"
fi

case $arch in
	armel)
#		kernelurl="http://yoush.homelinux.org:8079/nikita/armel-qemubuilder/vmlinuz-2.6.26-versatile-qemu"
#		kernelref="http://yoush.homelinux.org:8079/tech/setting-up-armel-qemubuilder"
		kernelurl="http://people.debian.org/~aurel32/qemu/armel/vmlinuz-2.6.26-1-versatile"
		initrdurl="http://people.debian.org/~aurel32/qemu/armel/initrd.img-2.6.26-1-versatile"
		kernelref="http://people.debian.org/~aurel32/qemu/armel/"
	;;
	mipsel)
		kernelurl="http://people.debian.org/~aurel32/qemu/mipsel/vmlinux-2.6.26-1-4kc-malta"
		kernelref="http://people.debian.org/~aurel32/qemu/mipsel/"
	;;
	*)
		exit1 "unsupported architecture: \"$arch\""
	;;
esac

basepath="/var/cache/pbuilder/base-$pool.qemu"
aptcache=""
buildresult="$HOME/src/pbuild-$pool/"
qemudir="/var/cache/pbuilder/qemu-$pool/"

makepaths=''
for path in "$buildresult" "$qemudir"; do
	if [ ! -d "$path" ]; then
		echo "W: Needed path \"$path\" does not exist"
		makepaths='yes'
	fi
done
if [ "$makepaths" = 'yes' ]; then
	[ "$force" = 'yes' ] \
		|| ask 'Create the missing path(s)' \
		|| exit1 "Cannot continue without those missing paths"
	mkdir -p "$buildresult"
	sudo mkdir -p "$qemudir"
fi

if [ -f "$basepath" ]; then
	echo "W: Needed path \"$basepath\" already exists"
	[ "$force" = 'yes' ] \
		|| ask 'Remove the path' \
		|| exit1 "Cannot continue with that path already there"
	sudo rm "$basepath"
fi

for url in $kernelurl $initrdurl; do
	file="$qemudir/$(basename $url)"
	if [ -f "$file" ]; then
		echo "W: file  \"$file\" already exists"
		if [ "$force" = 'yes' ] || ask 'Replace old file'; then
			sudo rm "$file"
		fi
	fi
done
for url in $kernelurl $initrdurl; do
	file="$qemudir/$(basename $url)"
	if ! [ -f "$qemudir/$kernel" ]; then
		sudo wget -O "$file" "$kernelurl"
	fi
done

if [ -f "$qemudir/cfg" ]; then
	echo "W: Configfile  \"$qemydir/cfg\" already exists"
	if [ "$force" = 'yes' ] || ask 'Overwrite old config'; then
		sudo rm "$qemudir/cfg"
	fi
fi

if ! [ -f "$qemudir/cfg" ]; then
	sudo sh -c "cat >\"$qemudir/cfg\"" <<EOF
# kernel origin: $kernelurl
# more info: $kernelref
ARCH=$arch
MEMORY_MEGS=256
${kernelurl:+KERNEL_IMAGE=$qemudir/$(basename $kernelurl)}
${initrdurl:+INITRD=$qemudir/$(basename $initrdurl)}
MIRRORSITE=http://auryn:9999/debian
#ARCH_DISKDEVICE=sd
EOF
fi

if [ -n "$othermirrors" ]; then
echo "$othermirrors" | perl -e "while (<>) {/\w/ and unshift @m, '--othermirror', \$_};"\
"exec 'sudo', 'qemubuilder', '--create', '--buildresult', '$buildresult', '--distribution', '$distro', '--basepath', '$basepath', '--aptcache', '$aptcache', '--configfile', '$qemudir/cfg', @m"
else
perl -e "exec 'sudo', 'qemubuilder', '--create', '--buildresult', '$buildresult', '--distribution', '$distro', '--basepath', '$basepath', '--aptcache', '$aptcache', '--configfile', '$qemudir/cfg'"
fi