#!/bin/sh
#
# vim: set ts=4 sw=4 et:
#
#-
# Copyright (c) 2009-2015 Juan Romero Pardines.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#-
trap 'error_out $? $LINENO' INT TERM 0
umask 022

readonly REQUIRED_PKGS="base-files libgcc dash coreutils sed tar gawk syslinux grub-i386-efi grub-x86_64-efi squashfs-tools xorriso"
readonly INITRAMFS_PKGS="binutils xz device-mapper dhclient dracut-network"
readonly PROGNAME=$(basename "$0")

info_msg() {
    printf "\033[1m$@\n\033[m"
}
die() {
    info_msg "ERROR: $@"
    error_out 1 $LINENO
}
print_step() {
    CURRENT_STEP=$((CURRENT_STEP+1))
    info_msg "[${CURRENT_STEP}/${STEP_COUNT}] $@"
}
mount_pseudofs() {
    for f in sys dev proc; do
        mkdir -p "$ROOTFS"/$f
        mount --bind /$f "$ROOTFS"/$f
    done
}
umount_pseudofs() {
    umount -f "$ROOTFS"/sys >/dev/null 2>&1
    umount -f "$ROOTFS"/dev >/dev/null 2>&1
    umount -f "$ROOTFS"/proc >/dev/null 2>&1
}
error_out() {
    umount_pseudofs
    [ -d "$BUILDDIR" -a -z "$KEEP_BUILDDIR" ] && rm -rf "$BUILDDIR"
    exit "${1:=0}"
}

usage() {
    cat <<_EOF
Usage: $PROGNAME [options]

Options:
 -a <xbps-arch>     Set XBPS_ARCH (do not use it unless you know what it is)
 -b <system-pkg>    Set an alternative base-system package (defaults to base-system).
 -r <repo-url>      Use this XBPS repository (may be specified multiple times).
 -c <cachedir>      Use this XBPS cache directory (a subdirectory of current 
directory if unset).
 -k <keymap>        Default keymap to use (us if unset)
 -l <locale>        Default locale to use (en_US.UTF-8 if unset).
 -i <lz4|gzip|bzip2|xz> Compression type for the initramfs image (xz if unset).
 -s <gzip|lzo|xz>     Compression type for the squashfs image (xz if unset)
 -S <freesize>      Allocate this free size (MB) for the rootfs.
 -o <file>          Output file name for the ISO image (auto if unset).
 -p "pkg pkgN ..."  Install additional packages into the ISO image.
 -I <includedir>    Include directory structure under given path into rootfs

 -C "cmdline args"  Add additional kernel command line arguments.
 -T "title"         Modify the bootloader title.
 -K                 Do not remove builddir.

The $PROGNAME script generates a live image of the Void Linux distribution.
This ISO image can be written to a CD/DVD-ROM or any USB stick.
_EOF
    exit 1
}

copy_void_keys() {
    mkdir -p "$1"/var/db/xbps/keys
    cp keys/*.plist "$1"/var/db/xbps/keys
}

copy_void_conf() {
    install -Dm644 data/void-vpkgs.conf "$1"/usr/share/xbps.d/void-virtualpkgs.conf
}

copy_dracut_files() {
    mkdir -p "$1"/usr/lib/dracut/modules.d/01vmklive
    cp dracut/vmklive/* "$1"/usr/lib/dracut/modules.d/01vmklive/
}

copy_autoinstaller_files() {
    mkdir -p "$1"/usr/lib/dracut/modules.d/01autoinstaller
    cp dracut/autoinstaller/* "$1"/usr/lib/dracut/modules.d/01autoinstaller/
}

install_prereqs() {
    copy_void_conf "$VOIDHOSTDIR"
    XBPS_ARCH=$ARCH "$XBPS_INSTALL_CMD" -r "$VOIDHOSTDIR" ${XBPS_REPOSITORY} \
         -c "$XBPS_HOST_CACHEDIR" -y $REQUIRED_PKGS
    [ $? -ne 0 ] && die "Failed to install required software, exiting..."
}

install_packages() {
    copy_void_conf "$ROOTFS"

    XBPS_ARCH=$BASE_ARCH "${XBPS_INSTALL_CMD}" -r "$ROOTFS" \
        ${XBPS_REPOSITORY} -c "$XBPS_CACHEDIR" -yn $PACKAGE_LIST $INITRAMFS_PKGS
    [ $? -ne 0 ] && die "Missing required binary packages, exiting..."

    mount_pseudofs

    LANG=C XBPS_ARCH=$BASE_ARCH "${XBPS_INSTALL_CMD}" -U -r "$ROOTFS" \
        ${XBPS_REPOSITORY} -c "$XBPS_CACHEDIR" -y $PACKAGE_LIST $INITRAMFS_PKGS
    [ $? -ne 0 ] && die "Failed to install $PACKAGE_LIST"

    xbps-reconfigure -r "$ROOTFS" -f base-files >/dev/null 2>&1
    chroot "$ROOTFS" env -i xbps-reconfigure -f base-files

    # Enable choosen UTF-8 locale and generate it into the target rootfs.
    if [ -f "$ROOTFS"/etc/default/libc-locales ]; then
        sed -e "s/\#\(${LOCALE}.*\)/\1/g" -i "$ROOTFS"/etc/default/libc-locales
    fi
    chroot "$ROOTFS" env -i xbps-reconfigure -a

    if [ -x installer.sh ]; then
        install -Dm755 installer.sh "$ROOTFS"/usr/sbin/void-installer
    else
        install -Dm755 /usr/sbin/void-installer "$ROOTFS"/usr/sbin/void-installer
    fi
    # Cleanup and remove useless stuff.
    rm -rf "$ROOTFS"/var/cache/* "$ROOTFS"/run/* "$ROOTFS"/var/run/*
}

copy_include_directory() {
    find "$INCLUDE_DIRECTORY" -mindepth 1 -maxdepth 1 -exec cp -rfpPv {} "$ROOTFS"/ \;
}

generate_initramfs() {
    local _args

    copy_dracut_files "$ROOTFS"
    copy_autoinstaller_files "$ROOTFS"
    if [ "$BASE_SYSTEM_PKG" = "base-system-systemd" ]; then
        _args="--add systemd"
    else
        _args="--omit systemd"
    fi
    chroot "$ROOTFS" env -i /usr/bin/dracut -N --"${INITRAMFS_COMPRESSION}" \
        --add-drivers "ahci" --force-add "vmklive autoinstaller" ${_args} "/boot/initrd" $KERNELVERSION
    [ $? -ne 0 ] && die "Failed to generate the initramfs"

    mv "$ROOTFS"/boot/initrd "$BOOT_DIR"
    cp "$ROOTFS"/boot/vmlinuz-$KERNELVERSION "$BOOT_DIR"/vmlinuz
}

cleanup_rootfs() {
    for f in ${INITRAMFS_PKGS}; do
        revdeps=$(xbps-query -r "$ROOTFS" -X $f)
        if [ -n "$revdeps" ]; then
            xbps-pkgdb -r "$ROOTFS" -m auto $f
        else
            xbps-remove -r "$ROOTFS" -Ry ${f} >/dev/null 2>&1
        fi
    done
    rm -r "$ROOTFS"/usr/lib/dracut/modules.d/01vmklive
    rm -r "$ROOTFS"/usr/lib/dracut/modules.d/01autoinstaller
}

generate_isolinux_boot() {
    cp -f "$SYSLINUX_DATADIR"/isolinux.bin "$ISOLINUX_DIR"
    cp -f "$SYSLINUX_DATADIR"/ldlinux.c32 "$ISOLINUX_DIR"
    cp -f "$SYSLINUX_DATADIR"/libcom32.c32 "$ISOLINUX_DIR"
    cp -f "$SYSLINUX_DATADIR"/vesamenu.c32 "$ISOLINUX_DIR"
    cp -f "$SYSLINUX_DATADIR"/libutil.c32 "$ISOLINUX_DIR"
    cp -f "$SYSLINUX_DATADIR"/chain.c32 "$ISOLINUX_DIR"
    cp -f isolinux/isolinux.cfg.in "$ISOLINUX_DIR"/isolinux.cfg
    cp -f ${SPLASH_IMAGE} "$ISOLINUX_DIR"

    sed -i  -e "s|@@SPLASHIMAGE@@|$(basename "${SPLASH_IMAGE}")|" \
        -e "s|@@KERNVER@@|${KERNELVERSION}|" \
        -e "s|@@KEYMAP@@|${KEYMAP}|" \
        -e "s|@@ARCH@@|$BASE_ARCH|" \
        -e "s|@@LOCALE@@|${LOCALE}|" \
        -e "s|@@BOOT_TITLE@@|${BOOT_TITLE}|" \
        -e "s|@@BOOT_CMDLINE@@|${BOOT_CMDLINE}|" \
        "$ISOLINUX_DIR"/isolinux.cfg
}

generate_grub_efi_boot() {
    cp -f grub/grub.cfg "$GRUB_DIR"
    cp -f grub/grub_void.cfg.in "$GRUB_DIR"/grub_void.cfg
    sed -i  -e "s|@@SPLASHIMAGE@@|$(basename "${SPLASH_IMAGE}")|" \
        -e "s|@@KERNVER@@|${KERNELVERSION}|" \
        -e "s|@@KEYMAP@@|${KEYMAP}|" \
        -e "s|@@ARCH@@|$BASE_ARCH|" \
        -e "s|@@BOOT_TITLE@@|${BOOT_TITLE}|" \
        -e "s|@@BOOT_CMDLINE@@|${BOOT_CMDLINE}|" \
        -e "s|@@LOCALE@@|${LOCALE}|" "$GRUB_DIR"/grub_void.cfg
    mkdir -p "$GRUB_DIR"/fonts
    cp -f "$GRUB_DATADIR"/unicode.pf2 "$GRUB_DIR"/fonts

    modprobe -q loop || :

    # Create EFI vfat image.
    truncate -s 32M "$GRUB_DIR"/efiboot.img >/dev/null 2>&1
    mkfs.vfat -F12 -S 512 -n "grub_uefi" "$GRUB_DIR/efiboot.img" >/dev/null 2>&1

    GRUB_EFI_TMPDIR="$(mktemp --tmpdir="$HOME" -d)"
    LOOP_DEVICE="$(losetup --show --find "${GRUB_DIR}"/efiboot.img)"
    mount -o rw,flush -t vfat "${LOOP_DEVICE}" "${GRUB_EFI_TMPDIR}" >/dev/null 2>&1

    cp -a "$IMAGEDIR"/boot "$VOIDHOSTDIR"
    xbps-uchroot "$VOIDHOSTDIR" grub-mkstandalone -- \
		 --directory="/usr/lib/grub/i386-efi" \
		 --format="i386-efi" \
		 --output="/tmp/bootia32.efi" \
		 "boot/grub/grub.cfg"
    if [ $? -ne 0 ]; then
        umount "$GRUB_EFI_TMPDIR"
        losetup --detach "${LOOP_DEVICE}"
        die "Failed to generate EFI loader"
    fi
    mkdir -p "${GRUB_EFI_TMPDIR}"/EFI/BOOT
    cp -f "$VOIDHOSTDIR"/tmp/bootia32.efi "${GRUB_EFI_TMPDIR}"/EFI/BOOT/BOOTIA32.EFI
    xbps-uchroot "$VOIDHOSTDIR" grub-mkstandalone -- \
		 --directory="/usr/lib/grub/x86_64-efi" \
		 --format="x86_64-efi" \
		 --output="/tmp/bootx64.efi" \
		 "boot/grub/grub.cfg"
    if [ $? -ne 0 ]; then
        umount "$GRUB_EFI_TMPDIR"
        losetup --detach "${LOOP_DEVICE}"
        die "Failed to generate EFI loader"
    fi
    cp -f "$VOIDHOSTDIR"/tmp/bootx64.efi "${GRUB_EFI_TMPDIR}"/EFI/BOOT/BOOTX64.EFI
    umount "$GRUB_EFI_TMPDIR"
    losetup --detach "${LOOP_DEVICE}"
    rm -rf "$GRUB_EFI_TMPDIR"
}

generate_squashfs() {
    umount_pseudofs

    # Find out required size for the rootfs and create an ext3fs image off it.
    ROOTFS_SIZE=$(du -sm "$ROOTFS"|awk '{print $1}')
    if [ -z "$ROOTFS_FREESIZE" ]; then
        ROOTFS_FREESIZE="$((ROOTFS_SIZE/6))"
    fi
    mkdir -p "$BUILDDIR/tmp/LiveOS"
    truncate -s "$((ROOTFS_SIZE+ROOTFS_FREESIZE))M" \
	    "$BUILDDIR"/tmp/LiveOS/ext3fs.img >/dev/null 2>&1
    mkdir -p "$BUILDDIR/tmp-rootfs"
    mkfs.ext3 -F -m1 "$BUILDDIR/tmp/LiveOS/ext3fs.img" >/dev/null 2>&1
    mount -o loop "$BUILDDIR/tmp/LiveOS/ext3fs.img" "$BUILDDIR/tmp-rootfs"
    cp -a "$ROOTFS"/* "$BUILDDIR"/tmp-rootfs/
    umount -f "$BUILDDIR/tmp-rootfs"
    mkdir -p "$IMAGEDIR/LiveOS"

    "$VOIDHOSTDIR"/usr/bin/mksquashfs "$BUILDDIR/tmp" "$IMAGEDIR/LiveOS/squashfs.img" \
        -comp "${SQUASHFS_COMPRESSION}" || die "Failed to generate squashfs image"
    chmod 444 "$IMAGEDIR/LiveOS/squashfs.img"

    # Remove rootfs and temporary dirs, we don't need them anymore.
    rm -rf "$ROOTFS" "$BUILDDIR/tmp-rootfs" "$BUILDDIR/tmp"
}

generate_iso_image() {
    "$VOIDHOSTDIR"/usr/bin/xorriso -as mkisofs \
        -iso-level 3 -rock -joliet \
        -max-iso9660-filenames -omit-period \
        -omit-version-number -relaxed-filenames -allow-lowercase \
        -volid "VOID_LIVE" \
        -eltorito-boot boot/isolinux/isolinux.bin \
        -eltorito-catalog boot/isolinux/boot.cat \
        -no-emul-boot -boot-load-size 4 -boot-info-table \
        -eltorito-alt-boot -e boot/grub/efiboot.img -isohybrid-gpt-basdat -no-emul-boot \
        -isohybrid-mbr "$SYSLINUX_DATADIR"/isohdpfx.bin \
        -output "$CURDIR/$OUTPUT_FILE" "$IMAGEDIR" || die "Failed to generate ISO image"
}

#
# main()
#
while getopts "a:b:r:c:C:T:Kk:l:i:I:s:S:o:p:h" opt; do
    case $opt in
        a) BASE_ARCH="$OPTARG";;
        b) BASE_SYSTEM_PKG="$OPTARG";;
        r) XBPS_REPOSITORY="--repository=$OPTARG $XBPS_REPOSITORY";;
        c) XBPS_CACHEDIR="$OPTARG";;
        K) readonly KEEP_BUILDDIR=1;;
        k) KEYMAP="$OPTARG";;
        l) LOCALE="$OPTARG";;
        i) INITRAMFS_COMPRESSION="$OPTARG";;
        I) INCLUDE_DIRECTORY="$OPTARG";;
        s) SQUASHFS_COMPRESSION="$OPTARG";;
        S) ROOTFS_FREESIZE="$OPTARG";;
        o) OUTPUT_FILE="$OPTARG";;
        p) PACKAGE_LIST="$OPTARG";;
        C) BOOT_CMDLINE="$OPTARG";;
        T) BOOT_TITLE="$OPTARG";;
        h) usage;;
	*) usage;;
    esac
done
shift $((OPTIND - 1))

XBPS_REPOSITORY="$XBPS_REPOSITORY --repository=http://alpha.de.repo.voidlinux.org/current --repository=http://alpha.de.repo.voidlinux.org/current/musl"

ARCH=$(xbps-uhelper arch)

# Set defaults
: ${BASE_ARCH:=$(xbps-uhelper arch 2>/dev/null || uname -m)}
: ${XBPS_CACHEDIR:="$(pwd -P)"/xbps-cachedir-${BASE_ARCH}}
: ${XBPS_HOST_CACHEDIR:="$(pwd -P)"/xbps-cachedir-${ARCH}}
: ${KEYMAP:=us}
: ${LOCALE:=en_US.UTF-8}
: ${INITRAMFS_COMPRESSION:=xz}
: ${SQUASHFS_COMPRESSION:=xz}
: ${BASE_SYSTEM_PKG:=base-system}
: ${BOOT_TITLE:="Void Linux"}

# Required packages in the image for a working system.
PACKAGE_LIST="$BASE_SYSTEM_PKG $PACKAGE_LIST"

# Check for root permissions.
if [ "$(id -u)" -ne 0 ]; then
    die "Must be run as root, exiting..."
fi

readonly CURDIR="$PWD"  


ISO_VOLUME="VOID_LIVE"
if [ -n "$ROOTDIR" ]; then
    BUILDDIR=$(mktemp --tmpdir="$ROOTDIR" -d)
else
    BUILDDIR=$(mktemp --tmpdir="$(pwd -P)" -d)
fi
BUILDDIR=$(readlink -f "$BUILDDIR")
IMAGEDIR="$BUILDDIR/image"
ROOTFS="$IMAGEDIR/rootfs"
VOIDHOSTDIR="$BUILDDIR/void-host"
BOOT_DIR="$IMAGEDIR/boot"
ISOLINUX_DIR="$BOOT_DIR/isolinux"
GRUB_DIR="$BOOT_DIR/grub"
ISOLINUX_CFG="$ISOLINUX_DIR/isolinux.cfg"
CURRENT_STEP=0
STEP_COUNT=9
[ -n "${INCLUDE_DIRECTORY}" ] && ((STEP_COUNT=STEP_COUNT+1))

: ${SYSLINUX_DATADIR:="$VOIDHOSTDIR"/usr/share/syslinux}
: ${GRUB_DATADIR:="$VOIDHOSTDIR"/usr/share/grub}
: ${SPLASH_IMAGE:=data/splash.png}
: ${XBPS_INSTALL_CMD:=xbps-install}
: ${XBPS_REMOVE_CMD:=xbps-remove}
: ${XBPS_QUERY_CMD:=xbps-query}
: ${XBPS_RINDEX_CMD:=xbps-rindex}
: ${XBPS_UHELPER_CMD:=xbps-uhelper}
: ${XBPS_RECONFIGURE_CMD:=xbps-reconfigure}

mkdir -p "$ROOTFS" "$VOIDHOSTDIR" "$ISOLINUX_DIR" "$GRUB_DIR"

print_step "Synchronizing XBPS repository data..."
copy_void_keys "$ROOTFS"
copy_void_keys "$VOIDHOSTDIR"
XBPS_ARCH=$BASE_ARCH $XBPS_INSTALL_CMD -r "$ROOTFS" ${XBPS_REPOSITORY} -S
XBPS_ARCH=$ARCH $XBPS_INSTALL_CMD -r "$VOIDHOSTDIR" ${XBPS_REPOSITORY} -S

_linux_series=$(XBPS_ARCH=$BASE_ARCH $XBPS_QUERY_CMD -r "$ROOTFS" ${XBPS_REPOSITORY:=-R} -x linux|head -1)
_kver=$(XBPS_ARCH=$BASE_ARCH $XBPS_QUERY_CMD -r "$ROOTFS" ${XBPS_REPOSITORY:=-R} -p pkgver ${_linux_series})
KERNELVERSION=$($XBPS_UHELPER_CMD getpkgversion ${_kver})

: ${OUTPUT_FILE="void-live-${BASE_ARCH}-${KERNELVERSION}-$(date +%Y%m%d).iso"}

print_step "Installing software to generate the image: ${REQUIRED_PKGS} ..."
install_prereqs

mkdir -p "$ROOTFS"/etc
[ -s data/motd ] && cp data/motd "$ROOTFS"/etc
[ -s data/issue ] && cp data/issue "$ROOTFS"/etc

print_step "Installing void pkgs into the rootfs: ${PACKAGE_LIST} ..."
install_packages

if [ -n "${INCLUDE_DIRECTORY}" ];then
    print_step "Copying directory structure into the rootfs: ${INCLUDE_DIRECTORY} ..."
    copy_include_directory
fi

print_step "Generating initramfs image ($INITRAMFS_COMPRESSION)..."
generate_initramfs

print_step "Generating isolinux support for PC-BIOS systems..."
generate_isolinux_boot

print_step "Generating GRUB support for EFI systems..."
generate_grub_efi_boot

print_step "Cleaning up rootfs..."
cleanup_rootfs

print_step "Generating squashfs image ($SQUASHFS_COMPRESSION) from rootfs..."
generate_squashfs

print_step "Generating ISO image..."
generate_iso_image

hsize=$(du -sh "$CURDIR/$OUTPUT_FILE"|awk '{print $1}')
info_msg "Created $(readlink -f "$CURDIR"/"$OUTPUT_FILE") ($hsize) successfully."