#!/bin/bash

set -e -u

# misc constants
readonly ALL_ARCHES='i686 x86_64'
readonly EFI_IMG_KBYTES=40000
readonly LOG_COLOR='\033[01;34m'
readonly ERR_COLOR='\033[00;31m'
readonly END_COLOR='\033[00m'

# edition-specific data
declare -ar VALID_INITS=('openrc' 'systemd')
declare -ar VALID_WMDES=('cli' 'lxde' 'mate' 'mini')

# environment
data_dir=/usr/share/parabolaiso/data
releng_dir=$(readlink -f ${0%/*})
initcpio_dir=${releng_dir}/../../parabolaiso/initcpio
packages_dir=${releng_dir}/packages
[ "`which mkparabolaiso 2> /dev/null`" ] || export PATH=$PATH:"${releng_dir}/../../parabolaiso"

# CLI option defaults
iso_arch='x86_64'
iso_init='systemd'
iso_wmde='cli'
enable_tts_brltty='false'
enable_offline_install='false'
iso_version=$(date +%Y.%m.%d)
iso_label="PARA_$(date +%Y%m)"
iso_dirname='parabola'
pacman_conf_in=${releng_dir}/pacman.conf
work_dir=./work
out_dir=./out
verbose=''

# computed vars, pending CLI options
edition_init='' # deferred
edition_wmde='' # deferred
iso_edition=''  # deferred
archs=''        # deferred
launch_msg=''   # deferred
iso_title=''    # deferred
release_id=''   # deferred
iso_filename='' # deferred
arch=''         # deferred
pacman_conf=''  # deferred


_usage ()
{
    echo "usage ${0} [options]"
    echo
    echo " General options:"
    echo "    -A <iso_arch>      Target architecture - one of: [ 'dual' , 'i686' , 'x86_64' ]"
    echo "                        Default: ${iso_arch}"
    echo "    -I <iso_init>      Init system - one of: [ 'openrc' , 'systemd' ]"
    echo "                        Default: ${iso_init}"
    echo "    -W <iso_wmde>      Graphical environment - one of: [ 'cli' , 'lxde' , 'mini' ]"
    echo "                        Default: ${iso_wmde}"
    echo "    -S                 Enable speech and braille."
    echo "                        Default: '${enable_tts_brltty}'"
    echo "    -O                 Enable offline install."
    echo "                        Default: '' (net-install only)"
    echo "    -V <iso_version>   Release version string"
    echo "                        Default: ${iso_version}"
    echo "    -L <iso_label>     Set the iso volume label"
    echo "                        Default: ${iso_label}"
    echo "    -D <iso_dirname>   Set the name of the directory inside the ISO"
    echo "                        Default: ${iso_dirname}"
    echo "    -C                 Specify the pacman.conf file used for chroot install."
    echo "                        Default: '${pacman_conf_in}'"
    echo "    -w <work_dir>      Set the working directory"
    echo "                        Default: ${work_dir}"
    echo "    -o <out_dir>       Set the output directory"
    echo "                        Default: ${out_dir}"
    echo "    -v                 Enable verbose output"
    echo "    -h                 This help message"
    exit ${1}
}

LOG_STEP()  { printf "${LOG_COLOR}%s${END_COLOR}\n" "$(echo -e $*)" ; }
LOG_ERROR() { printf "${ERR_COLOR}%s${END_COLOR}\n" "$(echo -e $*)" ; }


# Helper function to run make_*() only one time per architecture.
run_once() {
    local buid_stamp="build.${1}_${arch}"

    if [[ ! -e ${work_dir}/${buid_stamp} ]]; then
        LOG_STEP "runnning build step: '${buid_stamp}'"
        $1
        touch ${work_dir}/${buid_stamp}
    fi
}

# Setup custom pacman.conf to cache packages on the target filesystem.
make_pacman_conf() {
    local stash_dir=${work_dir}/isorepo-${arch}
    local isorepo_dir=${work_dir}/${arch}/root-image/isorepo/

    # restore package cache from previous build
    if [[ -d ${stash_dir} ]]; then
        echo "restoring package cache from ${stash_dir}"
        mkdir -p ${isorepo_dir}
        mv ${stash_dir}/* ${isorepo_dir} || true
    fi

    cp ${pacman_conf_in} ${pacman_conf}

    # enable [isorepo]
    sed -i -E 's|^#?\s*CacheDir.+|CacheDir = '${isorepo_dir}'|g' ${pacman_conf}

    # enable [nonsystemd] for openrc ISOs
    if [[ "${iso_init}" == 'openrc' ]]
    then sed -i 'N ; s|^#\[nonsystemd\].*#Include|\[nonsystemd\]\nInclude|' ${pacman_conf}
    fi
}

# Base installation, plus needed packages (root-image)
make_basefs() {
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/${arch} -C ${pacman_conf} -D ${iso_dirname} init
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/${arch} -C ${pacman_conf} -D ${iso_dirname} -p "memtest86+ mkinitcpio-nfs-utils nbd" install
}

# Additional packages (root-image)
make_packages() {
    local _base_packages_msg="standard packages as declared in the following files:"
    local _extra_packages_msg="non-graphical packages as declared in the following files:"
    # standard package lists
    local _install_base_lists=$( ls ${packages_dir}/packages-{all,${iso_init}}.{all,${arch}} 2> /dev/null || true)
    local _cache_base_lists=$(   ls ${packages_dir}/cache-{all,${iso_init}}.{all,${arch}}    2> /dev/null || true)
    # extra package lists
    local _install_extra_lists=$(ls ${packages_dir}/packages-gui.{all,${arch}}               2> /dev/null || true)
    local _cache_extra_lists=$(  ls ${packages_dir}/cache-gui.{all,${arch}}                  2> /dev/null || true)
    # init-specific extra package lists
    local _install_init_lists=$( ls ${packages_dir}/packages-${iso_init}-gui.{all,${arch}}   2> /dev/null || true)
    local _cache_init_lists=$(   ls ${packages_dir}/cache-${iso_init}-gui.{all,${arch}}      2> /dev/null || true)
    # wmde-specific extra package lists
    local _install_wmde_lists=$( ls ${packages_dir}/packages-${iso_wmde}.{all,${arch}}       2> /dev/null || true)
    local _cache_wmde_lists=$(   ls ${packages_dir}/cache-${iso_wmde}.{all,${arch}}          2> /dev/null || true)
    _install_base_lists=${_install_base_lists// /}
    _cache_base_lists=${_cache_base_lists// /}
    _install_extra_lists=${_install_extra_lists// /}
    _cache_extra_lists=${_cache_extra_lists// /}
    _install_init_lists=${_install_init_lists// /}
    _cache_init_lists=${_cache_init_lists// /}
    _install_wmde_lists=${_install_wmde_lists// /}
    _cache_wmde_lists=${_cache_wmde_lists// /}
    # collect standard packages
    local _install_base_packages=$(   [ "${_install_base_lists}"  ] && grep -hv ^# ${_install_base_lists})
    local _cache_base_packages=$(     [ "${_cache_base_lists}"    ] && grep -hv ^# ${_cache_base_lists})
    # collect extra packages
    local _install_basegui_packages=$([ "${_install_extra_lists}" ] && grep -hv ^# ${_install_extra_lists})
    local _cache_basegui_packages=$(  [ "${_cache_extra_lists}"   ] && grep -hv ^# ${_cache_extra_lists})
    # collect init-specific extra packages
    local _install_init_packages=$(   [ "${_install_init_lists}"  ] && grep -hv ^# ${_install_init_lists})
    local _cache_init_packages=$(     [ "${_cache_init_lists}"    ] && grep -hv ^# ${_cache_init_lists})
    # collect wmde-specific extra packages
    local _install_wmde_packages=$(   [ "${_install_wmde_lists}"  ] && grep -hv ^# ${_install_wmde_lists})
    local _cache_wmde_packages=$(     [ "${_cache_wmde_lists}"    ] && grep -hv ^# ${_cache_wmde_lists})
    if [[ "${iso_wmde}" != 'cli' && "${iso_wmde}" != 'mini' ]]; then
        _install_wmde_lists="${_install_extra_lists} ${_install_init_lists} ${_install_wmde_lists}"
        _cache_wmde_lists="${_cache_extra_lists} ${_cache_init_lists} ${_cache_wmde_lists}"
        _install_wmde_packages="${_install_basegui_packages} ${_install_init_packages} ${_install_wmde_packages}"
        _cache_wmde_packages="${_cache_basegui_packages} ${_cache_init_packages} ${_cache_wmde_packages}"
    fi
    _install_wmde_lists=${_install_wmde_lists// /}
    _cache_wmde_lists=${_cache_wmde_lists// /}
    _install_base_packages=${_install_base_packages// /}
    _cache_base_packages=${_cache_base_packages// /}
    _install_wmde_packages=${_install_wmde_packages// /}
    _cache_wmde_packages=${_cache_wmde_packages// /}

    # display results
    local _install_packages="${_install_base_packages} ${_install_wmde_packages}"
    local _cache_packages="${_cache_base_packages} ${_cache_wmde_packages}"
    _install_packages=${_install_packages// /}
    _cache_packages=${_cache_packages// /}
    [ "${_install_base_packages}" ] && echo "Installing ${_base_packages_msg}"  && echo "${_install_base_lists}"  | sed "s/.*\//\t/"
    [ "${_cache_base_packages}"   ] && echo "Caching ${_base_packages_msg}"     && echo "${_cache_base_lists}"    | sed "s/.*\//\t/"
    [ "${_install_wmde_packages}" ] && echo "Installing ${_extra_packages_msg}" && echo "${_install_wmde_lists}"  | sed "s/.*\//\t/"
    [ "${_cache_wmde_packages}"   ] && echo "Caching ${_extra_packages_msg}"    && echo "${_cache_wmde_lists}"    | sed "s/.*\//\t/"

    # install packages
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/${arch} -C ${pacman_conf} -D ${iso_dirname} -p "${_install_packages}" install

    # create live environment local repo or stash package cache
    if [[ "$enable_offline_install" == 'true' ]]; then
        if [[ -n "${_cache_packages}" ]]; then
            # download any cache packages and prune obsolete packages
            echo 'downloading "cache-only" packages'
            setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/${arch} -C ${pacman_conf} -D ${iso_dirname} -p "${_cache_packages}" cache
        fi

        # create 'isorepo' for offline install
        echo "creating 'isorepo' for offline install"
        pushd ${work_dir}/${arch}/root-image/isorepo > /dev/null
        setarch ${arch} repo-add --new isorepo.db.tar.gz ./*
        popd                                         > /dev/null
    else
        # stash package cache for next build
        echo "stashing package cache to ${work_dir}/isorepo-${arch}"
        mkdir -p ${work_dir}/isorepo-${arch}/
        mv       ${work_dir}/${arch}/root-image/isorepo/* ${work_dir}/isorepo-${arch}/
        rmdir    ${work_dir}/${arch}/root-image/isorepo
    fi
}

# Copy mkinitcpio parabolaiso hooks and build initramfs (root-image)
make_setup_mkinitcpio() {
    local _hook

    for _hook in parabolaiso parabolaiso_shutdown parabolaiso_pxe_common parabolaiso_pxe_nbd parabolaiso_pxe_http parabolaiso_pxe_nfs parabolaiso_loop_mnt; do
        cp ${initcpio_dir}/hooks/${_hook} ${work_dir}/${arch}/root-image/usr/lib/initcpio/hooks
        cp ${initcpio_dir}/install/${_hook} ${work_dir}/${arch}/root-image/usr/lib/initcpio/install
    done
    cp ${initcpio_dir}/install/parabolaiso_kms ${work_dir}/${arch}/root-image/usr/lib/initcpio/install
    cp ${initcpio_dir}/hooks/parabolaiso_shutdown ${work_dir}/${arch}/root-image/usr/lib/initcpio
    cp ${releng_dir}/mkinitcpio.conf ${work_dir}/${arch}/root-image/etc/mkinitcpio-parabolaiso.conf
    [[ "${arch}" != 'i686' ]] && sed -i 's|pcmcia||' ${work_dir}/${arch}/root-image/etc/mkinitcpio-parabolaiso.conf
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/${arch} -C ${pacman_conf} -D ${iso_dirname} -r 'mkinitcpio -c /etc/mkinitcpio-parabolaiso.conf -k /boot/vmlinuz-linux-libre -g /boot/parabolaiso.img' run
}

# Customize installation (root-image)
make_customize_root_image() {
    cp -af ${releng_dir}/root-image ${work_dir}/${arch}

    echo "Customizing root image"
    ISO_TITLE="${iso_title}"                                                                  \
    ISO_INIT="${iso_init}"                                                                    \
    ISO_WMDE="${iso_wmde}"                                                                     \
    ISO_ARCH="${iso_arch}"                                                                    \
    ENABLE_OFFLINE_INSTALL="${enable_offline_install}"                                        \
    ENABLE_TTS_BRLTTY="${enable_tts_brltty}"                                                  \
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/${arch}                           \
                                             -C ${pacman_conf}                                \
                                             -D ${iso_dirname}                                \
                                             -r /root/customize_root_image.sh                 \
                                             run
    rm ${work_dir}/${arch}/root-image/root/customize_root_image*
}

# Prepare kernel/initramfs ${iso_dirname}/boot/
make_boot() {
    mkdir -p ${work_dir}/iso/${iso_dirname}/boot/${arch}
    cp ${work_dir}/${arch}/root-image/boot/parabolaiso.img ${work_dir}/iso/${iso_dirname}/boot/${arch}/parabolaiso.img
    cp ${work_dir}/${arch}/root-image/boot/vmlinuz-linux-libre ${work_dir}/iso/${iso_dirname}/boot/${arch}/vmlinuz
}

# Add other aditional/extra files to ${iso_dirname}/boot/
make_boot_extra() {
    cp ${work_dir}/${arch}/root-image/boot/memtest86+/memtest.bin ${work_dir}/iso/${iso_dirname}/boot/memtest
    cp ${work_dir}/${arch}/root-image/usr/share/licenses/common/GPL2/license.txt ${work_dir}/iso/${iso_dirname}/boot/memtest.COPYING
}

# Prepare /${iso_dirname}/boot/syslinux
make_syslinux() {
    mkdir -p ${work_dir}/iso/${iso_dirname}/boot/syslinux
    for _cfg in ${releng_dir}/syslinux/*.cfg; do
        sed "s|%PARABOLAISO_LABEL%|${iso_label}|g;
             s|%INSTALL_DIR%|${iso_dirname}|g" ${_cfg} > ${work_dir}/iso/${iso_dirname}/boot/syslinux/${_cfg##*/}
    done
    cp ${releng_dir}/syslinux/syslinux-splash-${iso_init}.png ${work_dir}/iso/${iso_dirname}/boot/syslinux/splash.png
    cp ${work_dir}/${arch}/root-image/usr/lib/syslinux/bios/*.c32 ${work_dir}/iso/${iso_dirname}/boot/syslinux
    cp ${work_dir}/${arch}/root-image/usr/lib/syslinux/bios/lpxelinux.0 ${work_dir}/iso/${iso_dirname}/boot/syslinux
    cp ${work_dir}/${arch}/root-image/usr/lib/syslinux/bios/memdisk ${work_dir}/iso/${iso_dirname}/boot/syslinux
    mkdir -p ${work_dir}/iso/${iso_dirname}/boot/syslinux/hdt
    gzip -c -9 ${work_dir}/${arch}/root-image/usr/share/hwdata/pci.ids > ${work_dir}/iso/${iso_dirname}/boot/syslinux/hdt/pciids.gz
    gzip -c -9 ${work_dir}/${arch}/root-image/usr/lib/modules/*-gnu-*/modules.alias > ${work_dir}/iso/${iso_dirname}/boot/syslinux/hdt/modalias.gz

    # inject edition title into boot menu
    sed -i "s|_EDITION_TITLE_|${iso_title}|" ${work_dir}/iso/${iso_dirname}/boot/syslinux/parabolaiso_head.cfg

    # prune orphan boot entries for single-architecture ISO
    if [[ "${archs}" == 'i686' ]]; then
        rm ${work_dir}/iso/${iso_dirname}/boot/syslinux/parabolaiso_*64*.cfg
    elif [[ "${archs}" == 'x86_64' ]]; then
        rm ${work_dir}/iso/${iso_dirname}/boot/syslinux/parabolaiso_*32*.cfg
    fi
}

# Prepare /isolinux
make_isolinux() {
    mkdir -p ${work_dir}/iso/isolinux
    sed "s|%INSTALL_DIR%|${iso_dirname}|g" ${releng_dir}/isolinux/isolinux.cfg > ${work_dir}/iso/isolinux/isolinux.cfg
    cp ${work_dir}/${arch}/root-image/usr/lib/syslinux/bios/isolinux.bin         ${work_dir}/iso/isolinux/
    cp ${work_dir}/${arch}/root-image/usr/lib/syslinux/bios/isohdpfx.bin         ${work_dir}/iso/isolinux/
    cp ${work_dir}/${arch}/root-image/usr/lib/syslinux/bios/ldlinux.c32          ${work_dir}/iso/isolinux/
}

# Prepare /EFI
make_efi() {
    mkdir -p ${work_dir}/iso/EFI/boot
    if [[ "${iso_init}" == 'systemd' ]]; then
        cp ${work_dir}/x86_64/root-image/usr/lib/systemd/boot/efi/systemd-bootx64.efi ${work_dir}/iso/EFI/boot/bootx64.efi
    fi

    mkdir -p ${work_dir}/iso/loader/entries
    cp ${releng_dir}/efiboot/loader/loader.conf                       ${work_dir}/iso/loader/
    cp ${releng_dir}/efiboot/loader/entries/uefi-shell-v2-x86_64.conf ${work_dir}/iso/loader/entries/
    cp ${releng_dir}/efiboot/loader/entries/uefi-shell-v1-x86_64.conf ${work_dir}/iso/loader/entries/

    sed "s|%PARABOLAISO_LABEL%|${iso_label}|g;
         s|%INSTALL_DIR%|${iso_dirname}|g" \
        ${releng_dir}/efiboot/loader/entries/parabolaiso-x86_64-usb.conf > ${work_dir}/iso/loader/entries/parabolaiso-x86_64.conf

    # EFI Shell 2.0 for UEFI 2.3+ ( http://sourceforge.net/apps/mediawiki/tianocore/index.php?title=UEFI_Shell )
    cp ${data_dir}/Shell.efi ${work_dir}/iso/EFI/shellx64_v2.efi
    # EFI Shell 1.0 for non UEFI 2.3+ ( http://sourceforge.net/apps/mediawiki/tianocore/index.php?title=Efi-shell )
    cp ${data_dir}/Shell_Full.efi ${work_dir}/iso/EFI/shellx64_v1.efi
}

# Prepare efiboot.img::/EFI for "El Torito" EFI boot mode
make_efiboot() {
    # Cleanup in case of previous aborted run
    while mount | grep ${work_dir}/efiboot > /dev/null; do umount ${work_dir}/efiboot; sleep 1; done;
    rm ${work_dir}/iso/EFI/parabolaiso/efiboot.img 2> /dev/null || true

    # create EFI image
    mkdir -p ${work_dir}/iso/EFI/parabolaiso
    truncate -s ${EFI_IMG_KBYTES}K ${work_dir}/iso/EFI/parabolaiso/efiboot.img
    mkfs.vfat -n PARABOLAISO_EFI ${work_dir}/iso/EFI/parabolaiso/efiboot.img

    mkdir -p ${work_dir}/efiboot
    mkdir -p ${work_dir}/efiboot-staging
    mount ${work_dir}/iso/EFI/parabolaiso/efiboot.img ${work_dir}/efiboot

    mkdir -p ${work_dir}/efiboot-staging/EFI/parabolaiso
    cp ${work_dir}/iso/${iso_dirname}/boot/x86_64/vmlinuz         ${work_dir}/efiboot-staging/EFI/parabolaiso/vmlinuz.efi
    cp ${work_dir}/iso/${iso_dirname}/boot/x86_64/parabolaiso.img ${work_dir}/efiboot-staging/EFI/parabolaiso/parabolaiso.img

    mkdir -p ${work_dir}/efiboot-staging/EFI/boot
    if [[ "${iso_init}" == 'systemd' ]]; then
        cp ${work_dir}/x86_64/root-image/usr/lib/systemd/boot/efi/systemd-bootx64.efi ${work_dir}/efiboot-staging/EFI/boot/bootx64.efi
    fi

    mkdir -p ${work_dir}/efiboot-staging/loader/entries
    cp ${releng_dir}/efiboot/loader/loader.conf                           ${work_dir}/efiboot-staging/loader/
    cp ${releng_dir}/efiboot/loader/entries/uefi-shell-v2-x86_64.conf     ${work_dir}/efiboot-staging/loader/entries/
    cp ${releng_dir}/efiboot/loader/entries/uefi-shell-v1-x86_64.conf     ${work_dir}/efiboot-staging/loader/entries/
    sed "s|%PARABOLAISO_LABEL%|${iso_label}|g;
         s|%INSTALL_DIR%|${iso_dirname}|g" \
        ${releng_dir}/efiboot/loader/entries/parabolaiso-x86_64-cd.conf > ${work_dir}/efiboot-staging/loader/entries/parabolaiso-x86_64.conf

    cp ${work_dir}/iso/EFI/shellx64_v2.efi ${work_dir}/efiboot-staging/EFI/
    cp ${work_dir}/iso/EFI/shellx64_v1.efi ${work_dir}/efiboot-staging/EFI/

    local efi_kbytes=$(($(du -ks ${work_dir}/efiboot-staging | cut -f 1) + 32))
    if [[ ${efi_kbytes} -lt $(( ${EFI_IMG_KBYTES} )) ]]; then
        echo "Populating EFI image (${efi_kbytes}KB)"
        cp -rT ${work_dir}/efiboot-staging ${work_dir}/efiboot
        rm -rf ${work_dir}/efiboot-staging
        umount ${work_dir}/efiboot
    else
        echo "Error: Not enough space on EFI image (${EFI_IMG_KBYTES}KB - need ${efi_kbytes}KB)"
        umount ${work_dir}/efiboot
        exit 1
    fi
}

# Copy aitab
make_aitab() {
    mkdir -p ${work_dir}/iso/${iso_dirname}
    cp ${releng_dir}/aitab ${work_dir}/iso/${iso_dirname}/aitab
}

# Build all filesystem images specified in aitab (.fs.sfs .sfs)
make_prepare() {
    cp -a -l -f ${work_dir}/${arch}/root-image ${work_dir}/
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/ -D ${iso_dirname} -C ${pacman_conf} pkglist
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/ -D ${iso_dirname} -C ${pacman_conf} prepare

    rm -rf ${work_dir}/root-image
    # rm -rf ${work_dir}/${arch}/root-image (if low space, this helps)
}

# Build ISO
make_iso() {
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/ -D ${iso_dirname} checksum
    setarch ${arch} mkparabolaiso ${verbose} -w ${work_dir}/ -D ${iso_dirname} -L ${iso_label} -o ${out_dir}/ iso ${iso_filename}
}


## prepare state ##

# collect CLI options
while getopts 'A:I:W:SOV:L:D:C:w:o:vh' arg; do
    case "${arg}" in
        A) iso_arch="${OPTARG}" ;;
        I) iso_init="${OPTARG}" ;;
        W) iso_wmde="${OPTARG}" ;;
        S) enable_tts_brltty='true' ;;
        O) enable_offline_install='true' ;;
        V) iso_version="${OPTARG}" ;;
        L) iso_label="${OPTARG}" ;;
        D) iso_dirname="${OPTARG}" ;;
        C) pacman_conf_in="${OPTARG}" ;;
        w) work_dir="${OPTARG}" ;;
        o) out_dir="${OPTARG}" ;;
        v) verbose="-v" ;;
        h) _usage 0 ;;
        *)
           echo "Invalid argument '${arg}'"
           _usage 1
           ;;
    esac
done

# compute build configuration
edition_init=$( case "${iso_init}" in 'openrc') echo 'OpenRC' ;; 'systemd') echo 'SystemD' ;; esac )
edition_wmde=${iso_wmde^^}
iso_edition=${edition_init}/${edition_wmde}
case "${iso_arch}" in
    'i686'|'x86_64')
        archs=${iso_arch}
        launch_msg="Building single-architecture ${iso_edition} ISO for ${archs}"
        ;;
    *)
        archs=${ALL_ARCHES}
        iso_arch='dual'
        launch_msg="Building multi-architecture ${iso_edition} ISO for ${archs}"
        ;;
esac
if [[ "$enable_offline_install" == 'true' ]]; then
    iso_type='complete'
    launch_msg="${launch_msg} (offline install enabled)"
else
    iso_type='netinstall'
    launch_msg="${launch_msg} (net install only)"
fi
iso_title="Parabola GNU/Linux-libre Live - ${iso_edition} Edition ${iso_version}"
release_id=${iso_arch}-${iso_init}-${iso_wmde}-${iso_version}
iso_filename=parabola-${release_id}-${iso_type}.iso
[[ "${archs}" == 'i686' ]] && arch='i686' || arch='x86_64'
pacman_conf=${work_dir}/pacman.conf
out_dir=${out_dir}/${release_id}


## sanity checks ##

# sanitize mkparabolaiso args
iso_init=${iso_init// /}
iso_wmde=${iso_wmde// /}
iso_arch=${iso_arch// /}
iso_version=${iso_version// /}
iso_label=${iso_label// /}
iso_dirname=${iso_dirname// /}
enable_offline_install=${enable_offline_install// /}
enable_tts_brltty=${enable_tts_brltty// /}
pacman_conf_in=${pacman_conf_in// /}
work_dir=${work_dir// /}
out_dir=${out_dir// /}
iso_filename=${iso_filename// /}
pacman_conf=${pacman_conf// /}

# validate build environment
if [[ "$(uname -m)" != 'x86_64' ]] || ! grep 'ID_LIKE="*arch' /usr/lib/os-release > /dev/null; then
    LOG_ERROR "This script needs to be run on an x86_64 ArchLinux derrivative."
    exit 1
elif [[ ${EUID} -ne 0 ]]; then
    LOG_ERROR "This script needs to be run with root privileges."
    exit 1
elif ! pacman --version | grep libalpm > /dev/null; then
    LOG_ERROR "This script needs the 'pacman' package manager to be installed."
    exit 1
elif [[ "${archs}" =~ 'x86_64' ]] && ! pacman -Qi parabolaiso-data > /dev/null; then
    LOG_ERROR "x86_64 ISOs require the 'parabolaiso-data' package to be installed."
    exit 1
elif ! echo "${VALID_INITS[@]}" | tr " " "\n" | grep -E "^${iso_init}$" > /dev/null || \
     ! echo "${VALID_WMDES[@]}" | tr " " "\n" | grep -E "^${iso_wmde}$" > /dev/null    ; then
    LOG_ERROR "Invalid init/wm combination: '${iso_edition}'."
    exit 1
fi

# detect previously completed build
prefix=${work_dir}/build.make_
is_done=1
single_pass_build_steps='boot_extra syslinux isolinux aitab iso'
for build_step in $single_pass_build_steps
do [ -f "${prefix}${build_step}_${arch}" ] || is_done=0
done
multi_pass_build_steps='pacman_conf basefs packages setup_mkinitcpio customize_root_image boot prepare'
for build_step in $multi_pass_build_steps
do  for arch in ${archs}
    do  [ -f "${prefix}${build_step}_${arch}" ] || is_done=0
    done
done

if ! (($is_done)); then LOG_STEP ${launch_msg}; else LOG_STEP "Nothing to do"; exit; fi;


## build ISO ##

# prepare environment
chown -R 0:0 "${releng_dir}/root-image/"
mkdir -p ${work_dir}

# prepare target filesystems
for arch in ${archs}; do
    run_once make_pacman_conf
    run_once make_basefs
    run_once make_packages
    run_once make_setup_mkinitcpio
    run_once make_customize_root_image
done

# prepare kernels and initrds
for arch in ${archs}; do
    run_once make_boot
done

# prepare ISO
run_once make_boot_extra
run_once make_syslinux
run_once make_isolinux

# prepare EFI
if [[ "`echo ${archs} | grep x86_64`" ]]; then
    run_once make_efi
    run_once make_efiboot
fi

# prepare SFSs
run_once make_aitab
for arch in ${archs}; do
    run_once make_prepare
done

# build ISO
run_once make_iso

LOG_STEP "done - ISO: '${iso_filename}' created successfully"