#!/usr/bin/env sh
# build-iso.sh — assemble a Keru OS ISO from the built rootfs and kernel
#
# From-scratch approach (no archiso): we lay out the classic isohybrid
# structure manually, squash the rootfs, and generate the ISO with xorriso +
# isolinux/syslinux (or syslinux's isohybrid). This is the LFS/Debian-live
# style path.
#
# Requires on the build host: xorriso, squashfs-tools, syslinux/isolinux.

set -eu
. "$(dirname "$0")/common.sh"

ROOT="${ROOT:-/tmp/keru/root}"       # target rootfs (from make.conf)
ISO_OUT="${ISO_OUT:-$KERU_ROOT/iso/keru-$(date +%Y%m%d).iso}"
WORK="$KERU_ROOT/iso/work"
ISOIMG="$WORK/isolinux"

info "building Keru ISO -> $ISO_OUT"
[ -d "$ROOT" ] || die "rootfs not found at $ROOT (run build-root.sh first)"

have xorriso || die "xorriso not installed"
have mksquashfs || die "squashfs-tools not installed"

rm -rf "$WORK"; mkdir -p "$ISOIMG"
info "generating isolinux config"
cp /usr/lib/syslinux/bios/isolinux.bin "$ISOIMG/" || true
cp /usr/lib/syslinux/bios/ldlinux.c32 "$ISOIMG/" || true
cat > "$ISOIMG/isolinux.cfg" <<'EOF'
UI vesamenu.c32
DEFAULT keru
LABEL keru
    LINUX /boot/vmlinuz-keru
    INITRD /boot/initramfs-keru.img
    APPEND root=live:LABEL=KERU_LIVE toram quiet
EOF

info "packing rootfs into squashfs"
mksquashfs "$ROOT" "$WORK/keru.sfs" -noappend -comp xz

info "writing ISO (isohybrid)"
xorriso -as mkisofs \
    -o "$ISO_OUT" \
    -V KERU_LIVE \
    -b isolinux/isolinux.bin \
    -c isolinux/boot.cat \
    -no-emul-boot -boot-load-size 4 -boot-info-table \
    -isohybrid-mbr /usr/lib/syslinux/bios/isohdpfx.bin \
    "$WORK"

info "done: $ISO_OUT"