#!/bin/bash

set -e

unmount_virtual()
{
    umount "$1/proc" || true
    umount "$1/sys" || true
    umount "$1/tree/proc" || true
    umount "$1/tree/sys" || true
}

pass_snapshot()
{
    echo -n "$snapshotdir/$1-snapshot.tar.gz"
}

has_pass()
{
    if [ -e $(pass_snapshot "$1") ]
    then
        return 0
    else
        return 1
    fi
}

update_morph()
{
    local dir="$1"
    cp baserock-bootstrap "$dir/." # update bootstrap script
    rm -rf "$dir/tree/baserock/gits/morph"
    mkdir -p "$dir/tree/baserock/gits/morph"
    cp -r . "$dir/tree/baserock/gits/morph/."
}

run_pass()
{
    local dir="$1"
    local passname="$2"
    local tarball=$(pass_snapshot "$passname")

    if "$snapshot" && has_pass "$passname"
    then
        tar -C "$dir" -xf "$tarball"
        update_morph "$dir"
    else
        update_morph "$dir"
        "./do-squeeze-chroot" bash -x baserock-bootstrap "$passname" || exit 1
        if "$snapshot"
        then
            tar -C "$dir" -caf "$tarball" .
        fi
    fi
}

export LC_ALL=C

if [ "x$1" = x ]
then
    echo "Usage: $0 chroot-dir" 1>&2
    exit 1
fi

mkdir -p "$1"
dir="$1/squeeze-chroot"
: ${snapshot:=true}
snapshotdir="$1"

cat >"./do-squeeze-chroot" <<EOF
#!/bin/sh

# clear the temporary directory used outisde the chroot
export TMPDIR=

if mount -t proc proc "$dir/proc"; then
  trap "umount \"$dir/proc\"" INT TERM EXIT
  if mount -t sysfs sysfs "$dir/sys"; then
    trap "umount \"$dir/proc\" \"$dir/sys\"" INT TERM EXIT
    chroot "$dir" "\$@"
  fi
fi
EOF
chmod +x "./do-squeeze-chroot"

if ([ "x$DEBIAN_MIRROR" = x ] && echo DEBIAN_MIRROR is unspecified >&2) ||
    ([ "x$GIT_BUNDLES" = x ] && echo GIT_BUNDLES is unspecified >&2) ||
    ([ "x$LFS_MIRROR" = x ] && echo LFS_MIRROR is unspecified >&2)
then
    echo You have to set DEBIAN_MIRROR and other environment variables 1>&2
    exit 1
fi
#DEBIAN_MIRROR="http://192.168.1.185/debian"
#LFS_MIRROR=http://192.168.1.185/lfs/

unmount_virtual "$dir"
rm -rf "$dir"
mkdir "$dir"

chrootsnapshot="$snapshotdir/squeeze.tar.gz"
if "$snapshot" && [ -e "$chrootsnapshot" ]
then
    tar -C "$dir" -xf "$chrootsnapshot"
else
    debootstrap \
    --include=build-essential,\
gawk,bison,python,autoconf,autopoint,automake,gettext,libtool,\
help2man,texinfo,sudo,qemu-utils,parted,kpartx,mbr,extlinux \
squeeze "$dir" "$DEBIAN_MIRROR"

    # We need a backport of tar 1.26. On ARM, older versions (possibly
    # prior to 1.25) have a bug unpacking things onto an NFS filesystem.
    # code.liw.fi has the backport, so we'll add that to apt's sources.list
    # and install tar manually.
    cat <<EOF >> "$dir/etc/apt/sources.list"
deb http://code.liw.fi/debian squeeze main
EOF
    ./do-squeeze-chroot apt-get update
    ./do-squeeze-chroot apt-get install --allow-unauthenticated tar
    
    if "$snapshot"
    then
        tar -caf "$chrootsnapshot" -C "$dir" .
    fi
fi

hostname > "$dir/etc/hostname"
cat <<EOF > "$dir/etc/hosts"
127.0.0.1   localhost
127.0.1.1   `hostname`
EOF

if [ "x$LFS_MIRROR" = x ]; then
    cp wget-list "$dir/wget-list"
else
    perl -M'Env' -lpe 's|^.*/|$LFS_MIRROR|' wget-list >"$dir/wget-list"
fi


# Unpack existing snapshot, or run pass1 of bootstrap and then make snapshot.


if ! "$snapshot" || ! has_pass pass2a
then
    run_pass "$dir" pass1
fi


if ! "$snapshot" || ! has_pass pass2b
then
    run_pass "$dir" pass2a
fi

run_pass "$dir" pass2b
snapshot=false run_pass "$dir" pass3

echo "Passes 1, 2, and 3 of bootstrap done (possibly cached)."