#!/bin/bash

CPIOCONFIG="$(pwd)/archiso-mkinitcpio.conf"
DEF_CONFIG_DIR="$(pwd)/overlay"
PKGFILE="$(pwd)/packages.list"
PKGLIST=""
QUIET="y"
FORCE="n"
ADDON_DIR=""

command_name=""
work_dir=""
imgname=""

APPNAME=$(basename "${0}")

# usage: usage <exitvalue>
usage ()
{
    echo "usage ${APPNAME} [options] command <command options>"
    echo " general options:"
    echo "    -f               Force overwrite of working files/squashfs image/bootable image"
    echo "    -i CPIO_CONFIG   Use CONFIG file for mkinitcpio. default: ${CPIOCONFIG}"
    echo "    -P PKGFILE       File with list of packages to install. default: ${PKGFILE}"
    echo "    -p PACKAGE       Additional package to install, can be used multiple times"
    echo "    -a ADDON_DIR     Use addons from DIR. default: none"
    echo "    -t <iso,disk>    Type of image to create. Defaults to iso."
    echo "    -v               Enable verbose output."
    echo "    -h               This message."
    echo " commands:"
    echo " install <working dir>          : where to build the image root"
    echo " squash <working dir>           : generate a squashfs image of the installed root"
    echo " img <working dir> <image name> : build an image from the working directory"
    echo " all <working dir> <image name> : perform all of the above, in order"
    exit $1
}

while getopts 'i:P:p:a:t:fvh' arg; do
    case "${arg}" in
        i) CPIOCONFIG="${OPTARG}" ;;
        P) PKGFILE="${OPTARG}" ;;
        p) PKGLIST="${PKGLIST} ${OPTARG}" ;;
        a) ADDON_DIR="${OPTARG}" ;;
        t) IMG_TYPE="${OPTARG}" ;;
        f) FORCE="y" ;;
        v) QUIET="n" ;;
        h|?) usage 0 ;;
        *) echo "invalid argument '${arg}'"; usage 1 ;;
    esac
done

shift $(($OPTIND - 1))
echo "ARGS: $@"

[ $# -le 1 ] && usage 1

# do UID checking here so someone can at least get usage instructions
if [ "$EUID" != "0" ]; then
    echo "error: This script must be run as root."
    exit 1
fi

command_name="${1}"
case "${command_name}" in
    install) work_dir="${2}" ;;
    squash) work_dir="${2}" ;;
    img) work_dir="${2}"; imgname="${3}" ;;
    all) work_dir="${2}"; imgname="${3}" ;;
    *) echo "invalid command name '${command_name}'"; usage 1 ;;
esac

[ "x${work_dir}" = "x" ] && (echo "please specify a working directory" && usage 1)

imgroot="${work_dir}/img"
instroot="${work_dir}/install"

_kversion ()
{
    source ${instroot}/etc/mkinitcpio.d/kernel26.kver
    echo ${ALL_kver}
}

# usage: _pacman <packages>...
_pacman ()
{
    local ret
    if [ "${QUIET}" = "y" ]; then
        mkarchroot -f ${instroot} $* 2>&1 >/dev/null
        ret=$?
    else
        mkarchroot -f ${instroot} $*
        ret=$?
    fi
    if [ $ret -ne 0 ]; then
        exit 1
    fi
}

# usage: install_pkgfile <packagesfile>
install_pkgfile ()
{
    if [ -e "${1}" ]; then
        toinstall=""
        while read pkg; do
            toinstall="${toinstall} ${pkg}"
        done < ${1}
        _pacman "${toinstall}"
    else
        echo "error: Package file '${1}' does not exist, aborting."
        exit 1
    fi
}

# Go through the main commands in order. If 'all' was specified, then we want
# to do everything. Start with 'install'.
if [ "${command_name}" = "install" -o "${command_name}" = "all" ]; then
    echo "====> Installing/building image root"
    if [ -e "${work_dir}" -a "${FORCE}" = "n" ]; then
        echo "error: Working dir '${work_dir}' already exists, aborting."
        exit 1
    fi

    mkdir -p "${imgroot}"
    mkdir -p "${instroot}"

    echo "Installing packages..."
    echo " Installing packages from '${PKGFILE}'"
    install_pkgfile "${PKGFILE}"

    for pkg in ${PKGLIST}; do
        echo "   Installing package '${pkg}'"
        _pacman "${pkg}"
    done

    echo "Updating kernel module dependencies"
    kernelver=$(_kversion)
    depmod -a -b "${instroot}" "${kernelver}"
    # remove the initcpio images that were generated for the host system
    find "${instroot}/boot" -name *.img -delete

    echo "Creating default home directory"
    install -d -o1000 -g100 -m0755 "${instroot}/home/arch"

    # Cleanup
    echo "Cleaning up image root files..."
    find "${instroot}" -name *.pacnew -name *.pacsave -name *.pacorig -delete

    # delete a lot of unnecessary cache/log files
    kill_dirs="var/abs var/cache/man var/cache/pacman var/log/* var/mail tmp/* initrd"
    for x in ${kill_dirs}; do
        if [ -e "${instroot}/${x}" ]; then
            rm -rf "${instroot}/${x}"
        fi
    done

    # pacman DBs are big, delete all sync dbs
    rm -rf "${instroot}/var/lib/pacman/sync"

    # copy over kernel and grub configs for boot
    if [ -e "${instroot}/boot" -a -e "${DEF_CONFIG_DIR}/boot" ]; then
        rm -rf "${imgroot}/boot"
        cp -r "${instroot}/boot" "${imgroot}"
        cp -rf "${DEF_CONFIG_DIR}/boot" "${imgroot}"
    fi

    # TODO: this might belong somewhere else
    mkdir -p "${imgroot}/addons"
    if [ -d "${ADDON_DIR}" ]; then
        echo "Copying addons from ${ADDON_DIR}..."
        cp -r ${ADDON_DIR}/* "${imgroot}/addons"
    fi

    # always make an addon out of DEF_CONFIG_DIR
    echo "Creating default overlay..."
    if [ "${QUIET}" = "y" ]; then
        mksquashfs "${DEF_CONFIG_DIR}" "${imgroot}/addons/overlay.sqfs" -noappend >/dev/null
    else
        mksquashfs "${DEF_CONFIG_DIR}" "${imgroot}/addons/overlay.sqfs" -noappend
    fi
fi

# Squash is the next step.
if [ "${command_name}" = "squash" -o "${command_name}" = "all" ]; then
    echo "====> Generating SquashFS image"
    imagename="${imgroot}/archlive.sqfs"
    if [ -e "${imagename}" ]; then
        if [ "${FORCE}" = "y" ]; then
            echo -n "Removing old SquashFS image..."
            rm "${imagename}"
            echo "done."
        else
            echo "error: SquashFS image '${imagename}' already exists, aborting."
            exit 1
        fi
    fi

    echo "Creating squashfs image. This may take some time..."
    start=$(date +%s)
    if [ "${QUIET}" = "y" ]; then
        mksquashfs "${instroot}" "${imagename}" -noappend >/dev/null
    else
        mksquashfs "${instroot}" "${imagename}" -noappend
    fi
    minutes=$(echo $start $(date +%s) | awk '{ printf "%0.2f",($2-$1)/60 }')
    echo "Image creation done in $minutes minutes."
fi

# Finally, make the image.
if [ "${command_name}" = "img" -o "${command_name}" = "all" ]; then
    echo "====> Making bootable image"
    [ "x${imgname}" = "x" ] && (echo "Bootable image name must be specified" && usage 1)
    if [ -e "${imgname}" ]; then
        if [ "${FORCE}" = "y" ]; then
            echo "Removing existing bootable image..."
            rm -rf "${imgname}"
        else
            echo "error: Image '${imgname}' already exists, aborting."
            exit 1
        fi
    fi
    if [ ! -e "${CPIOCONFIG}" ]; then
        echo "error: mkinitcpio config '${CPIOCONFIG}' does not exist, aborting."
        exit 1
    fi

    kernelver=$(_kversion)
    basedir=${instroot}
    [ "${instroot:0:1}" != "/" ] && basedir="$(pwd)/${instroot}"
    echo "Generating initcpio for image..."
    if [ "${QUIET}" = "y" ]; then
        mkinitcpio -c "${CPIOCONFIG}" -b "${basedir}" -k "${kernelver}" -g "${imgroot}/boot/archlive.img" >/dev/null
        ret=$?
    else
        mkinitcpio -c "${CPIOCONFIG}" -b "${basedir}" -k "${kernelver}" -g "${imgroot}/boot/archlive.img"
        ret=$?
    fi
    if [ $ret -ne 0 ]; then
        echo "error: initcpio image creation failed..."
        exit 1
    fi

    cp ${instroot}/usr/lib/grub/i386-pc/* "${imgroot}/boot/grub"

    if [ "x$IMG_TYPE" == "xdisk" ]; then
        echo "Creating DISK image..."
        mkusbimg "${imgroot}" "${imgname}"
    else
        echo "Creating ISO image..."
        q=""
        [ "${QUIET}" = "y" ] && qflag="-q"
        mkisofs ${qflag} -r -l -b "boot/grub/stage2_eltorito" -uid 0 -gid 0 \
            -no-emul-boot -boot-load-size 4 -boot-info-table \
            -publisher "Arch Linux <archlinux.org>" \
            -input-charset=UTF-8 -p "prepared by $NAME" \
            -A "Arch Linux Live/Rescue CD" \
            -o "${imgname}" "${imgroot}"
    fi
fi

# vim:ts=4:sw=4:et: