#!/usr/bin/env bash
# ─────────────────────────────────────────────────────────────────────────────
# Arcline OS — live-session rootfs builder
#
#   scripts/build-live.sh <edition>
#
# Creates build/rootfs/<edition>-live: a bootable live-session rootfs used by
# the ISO. It starts from the CLEAN installed-system rootfs (so what you
# install is exactly what you booted), clones it, and layers on:
#
#   - live-boot / live-config / live-tools (boot the squashfs)
#   - a minimal X session (Xorg + openbox) for the graphical installer
#   - the Arcline graphical installer (installer/arcline-installer)
#   - the deploy tooling it needs (deploy-disk.sh + btrfs/init.sh + fstabs)
#
# The live rootfs itself is never what gets installed — the installer deploys
# the clean rootfs archive (staged into the ISO by build-iso.sh).
# ─────────────────────────────────────────────────────────────────────────────
set -euo pipefail
source "$(dirname "${BASH_SOURCE[0]}")/common.sh"

EDITION="${1:?usage: build-live.sh <edition>}"
validate_edition "$EDITION"
require_root "$0" "$@"

CLEAN="$ROOTFS_DIR/$EDITION"
LIVE_ROOT="$ROOTFS_DIR/$EDITION-live"

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

log "═══ building live session rootfs for $EDITION ═══"
rm -rf "$LIVE_ROOT"
cp -a "$CLEAN" "$LIVE_ROOT"

# ── chroot helpers ──────────────────────────────────────────────────────────
mount_pseudo() {
  mount --bind /dev "$LIVE_ROOT/dev"
  mount --bind /proc "$LIVE_ROOT/proc"
  mount --bind /sys "$LIVE_ROOT/sys"
  mount --bind /dev/pts "$LIVE_ROOT/dev/pts" 2>/dev/null || true
}
unmount_pseudo() {
  umount -l "$LIVE_ROOT/dev/pts" 2>/dev/null || true
  umount -l "$LIVE_ROOT/sys" 2>/dev/null || true
  umount -l "$LIVE_ROOT/proc" 2>/dev/null || true
  umount -l "$LIVE_ROOT/dev" 2>/dev/null || true
}
trap 'unmount_pseudo' EXIT
chroot_run() { chroot "$LIVE_ROOT" /bin/bash -c "$*"; }

# ── 2. install live session packages ────────────────────────────────────────
log "[1/4] installing live-boot + X + installer dependencies"
mount_pseudo
# deploy tooling (gdisk parted dosfstools btrfs-progs rsync) is needed by
# deploy-disk.sh, which the graphical installer runs against the target disk.
chroot_run "export DEBIAN_FRONTEND=noninteractive
apt-get update -qq
apt-get install -y --no-install-recommends \
  live-boot live-config-systemd live-tools \
  xserver-xorg x11-xserver-utils openbox \
  python3-gi gir1.2-gtk-3.0 \
  gdisk parted dosfstools btrfs-progs rsync \
  | tee /tmp/live-packages.log"

# Modern Xorg refuses to run as root, so the live session runs as a dedicated
# unprivileged user. It needs the tty group for the VT and video/input for
# DRM + input devices.
log "[1b/4] creating unprivileged session user (liveuser)"
chroot_run "useradd -m -s /bin/bash liveuser 2>/dev/null || true
usermod -aG tty,video,input,audio,cdrom,plugdev,users liveuser 2>/dev/null || true"

# ── 3. ship the graphical installer + deploy tooling ────────────────────────
log "[2/4] installing installer + deploy tooling"
install -Dm0755 "$ROOT/installer/arcline-installer" "$LIVE_ROOT/usr/local/bin/arcline-installer"

# The installer drives deploy-disk.sh; mirror the repo layout under
# /usr/lib/arcline so common.sh's ROOT resolution works unchanged.
install -Dm0755 "$ROOT/scripts/common.sh"      "$LIVE_ROOT/usr/lib/arcline/scripts/common.sh"
install -Dm0755 "$ROOT/scripts/deploy-disk.sh" "$LIVE_ROOT/usr/lib/arcline/scripts/deploy-disk.sh"
install -Dm0755 "$ROOT/scripts/apply-fstab.sh" "$LIVE_ROOT/usr/lib/arcline/scripts/apply-fstab.sh"
install -Dm0755 "$ROOT/btrfs/init.sh"          "$LIVE_ROOT/usr/lib/arcline/btrfs/init.sh"
for e in "${EDITIONS[@]}"; do
  install -Dm0644 "$ROOT/editions/$e/fstab" "$LIVE_ROOT/usr/lib/arcline/editions/$e/fstab"
done

# ── 4. live overlay (session autostart) + service wiring ────────────────────
log "[3/4] applying live overlay"
cp -a "$ROOT/overlays/live/." "$LIVE_ROOT/"

chroot_run "systemctl enable arcline-installer.service 2>/dev/null || true
systemctl mask sddm 2>/dev/null || true
systemctl set-default multi-user.target 2>/dev/null || true"

# the live session is disposable; give it a fresh identity
echo "arclines-live" > "$LIVE_ROOT/etc/hostname"
rm -f "$LIVE_ROOT/etc/machine-id"
: > "$LIVE_ROOT/etc/machine-id"

log "[4/4] cleaning live rootfs"
chroot_run "apt-get clean 2>/dev/null; rm -rf /var/lib/apt/lists/* /var/cache/apt/* /tmp/* /root/.bash_history"
unmount_pseudo

log "live rootfs ready: $LIVE_ROOT"