#!/usr/bin/env bash
# ─────────────────────────────────────────────────────────────────────────────
# Arcline OS — disk image builder (qcow2 / raw)
#
#   scripts/build-image.sh <edition> [--format qcow2|raw] [--size 4G] [--boot bios|efi]
#
# Produces a bootable disk image (the cloud edition's real output — and useful
# for testing server/workstation locally in a VM):
#
#   1. ensure the rootfs exists (build it if needed)
#   2. create a sparse raw file, attach a loop device
#   3. deploy-disk.sh writes the finished system (btrfs layout + GRUB + fstab)
#   4. optionally qemu-img convert to qcow2
#   5. artifact → build/artifacts/arcline-<edition>-<version>-<arch>.<ext> + sha256
#
# Requires root (for the loop device + deploy step).
# ─────────────────────────────────────────────────────────────────────────────
set -euo pipefail
source "$(dirname "${BASH_SOURCE[0]}")/common.sh"

EDITION="${1:?usage: build-image.sh <edition> [--format qcow2|raw] [--size 4G] [--boot bios|efi]}"
FORMAT="qcow2"
SIZE="4G"
BOOT="bios"

shift || true
while [[ $# -gt 0 ]]; do
  case "$1" in
    --format) FORMAT="${2:?}"; shift 2 ;;
    --size)   SIZE="${2:?}";   shift 2 ;;
    --boot)   BOOT="${2:?}";   shift 2 ;;
    *) die "unknown option '$1'" ;;
  esac
done

validate_edition "$EDITION"
[[ "$FORMAT" == "qcow2" || "$FORMAT" == "raw" ]] || die "--format must be qcow2|raw"
[[ "$BOOT" == "bios" || "$BOOT" == "efi" ]]    || die "--boot must be bios|efi"
require_root "$0" "$@"

command -v qemu-img >/dev/null || die "missing 'qemu-img' (package: qemu-utils)"
command -v losetup >/dev/null  || die "missing 'losetup' (package: util-linux)"

ROOTFS="$ROOTFS_DIR/$EDITION"
RAW="$IMAGE_DIR/$EDITION/arcline-$EDITION-$VERSION-$ARCH.raw"
EXT="$FORMAT"
ARTIFACT="$ARTIFACT_DIR/arcline-$EDITION-$VERSION-$ARCH.$EXT"

mkdir -p "$IMAGE_DIR/$EDITION" "$ARTIFACT_DIR"
rm -f "$RAW" "$ARTIFACT" "$ARTIFACT.sha256"

# ── 1. rootfs ───────────────────────────────────────────────────────────────
if [[ ! -d "$ROOTFS" ]]; then
  log "rootfs missing — building it first"
  "$ROOT/scripts/build-rootfs.sh" "$EDITION"
fi

# ── 2. sparse raw file + loop device ────────────────────────────────────────
log "creating ${SIZE} sparse image (edition $EDITION, $BOOT boot)"
truncate -s "$SIZE" "$RAW"
LOOP="$(losetup --find --show --partscan "$RAW")"
cleanup() { losetup -d "$LOOP" 2>/dev/null || true; }
trap cleanup EXIT
log "attached loop device: $LOOP"

# ── 3. deploy ───────────────────────────────────────────────────────────────
"$ROOT/scripts/deploy-disk.sh" "$LOOP" "$ROOTFS" "$EDITION" --boot "$BOOT"

# ── 4. convert ──────────────────────────────────────────────────────────────
losetup -d "$LOOP"
trap - EXIT

if [[ "$FORMAT" == "qcow2" ]]; then
  log "converting to qcow2"
  qemu-img convert -f raw -O qcow2 "$RAW" "$ARTIFACT"
  rm -f "$RAW"
else
  mv "$RAW" "$ARTIFACT"
fi

log "image artifact: $ARTIFACT"
sha256sum "$ARTIFACT" | tee "$ARTIFACT.sha256"