#!/bin/bash
# SamiOS Desktop ISO build script
#
# Builds a desktop ISO by merging the base packages.x86_64 with the
# desktop overlay (packages.x86_64.desktop) into a temporary profile,
# then running mkarchiso on that profile.
#
# Usage: sudo bash packaging/archiso/build-desktop.sh
set -euo pipefail

PROFILE_DIR="$(cd "$(dirname "$0")" && pwd)"
OUT_DIR="${OUT_DIR:-$PROFILE_DIR/out}"

# ── Create work dir via mktemp (not caller-selected) ─────────────────────
# We deliberately do NOT honor a caller-provided WORK_DIR for rm -rf
# safety. A caller-selected path is vulnerable to symlink races on
# shared /tmp. Instead, we create a root-owned mktemp directory.
WORK_DIR="$(mktemp -d /tmp/samios-desktop-build.XXXXXX)"
OUT_DIR="$(readlink -f "$OUT_DIR" 2>/dev/null || echo "$OUT_DIR")"

# ── Create temp profile (BEFORE this, no side effects) ──────────────────
TMP_PROFILE="$(mktemp -d /tmp/samios-desktop-profile.XXXXXX)"

cleanup() {
    rm -rf "$TMP_PROFILE" "$WORK_DIR"
}
trap cleanup EXIT

echo "Building SamiOS Desktop ISO..."
echo "Base profile:   $PROFILE_DIR"
echo "Temp profile:   $TMP_PROFILE"
echo "Work directory: $WORK_DIR"
echo "Output:         $OUT_DIR"

# ── Copy base profile (excluding output dir) ─────────────────────────────
for item in "$PROFILE_DIR"/* "$PROFILE_DIR"/.*; do
    [ -e "$item" ] || continue
    base="$(basename "$item")"
    case "$base" in
        out|.|..) continue ;;
    esac
    cp -a "$item" "$TMP_PROFILE/"
done

# ── Merge package lists ─────────────────────────────────────────────────
cat "$PROFILE_DIR/packages.x86_64" \
    "$PROFILE_DIR/packages.x86_64.desktop" \
    > "$TMP_PROFILE/packages.x86_64"

# Copy VERSION into the temp profile so profiledef.sh can find it
# (profiledef.sh walks up from its own directory looking for VERSION;
# without this copy, it falls back to 0.0.0-unknown)
# PROFILE_DIR is packaging/archiso, so VERSION is two levels up.
REPO_ROOT="$(cd "$PROFILE_DIR/../.." && pwd)"
if [ -f "$REPO_ROOT/VERSION" ]; then
    cp "$REPO_ROOT/VERSION" "$TMP_PROFILE/VERSION"
fi

# Verify the merged list has more packages than base alone
base_pkgs=$(grep -vE '^\s*#|^\s*$' "$PROFILE_DIR/packages.x86_64" | wc -l)
merged_pkgs=$(grep -vE '^\s*#|^\s*$' "$TMP_PROFILE/packages.x86_64" | wc -l)
if [ "$merged_pkgs" -le "$base_pkgs" ]; then
    echo "ERROR: merged package list ($merged_pkgs) not larger than base ($base_pkgs)"
    exit 1
fi
echo "Packages: $base_pkgs (base) + $((merged_pkgs - base_pkgs)) (desktop) = $merged_pkgs (total)"

# ── Enable SDDM display manager in the TEMP profile only ────────────────
# This goes into the temp profile, NOT the shared base airootfs, so
# base-only ISO builds are unaffected.
PRESET_DIR="$TMP_PROFILE/airootfs/etc/systemd/system-preset"
mkdir -p "$PRESET_DIR"
echo "enable sddm.service" > "$PRESET_DIR/00-samios-desktop.preset"

# Create the display-manager.service symlink (standard Arch way to
# enable a display manager — sddm gets activated on boot)
DM_LINK="$TMP_PROFILE/airootfs/etc/systemd/system/display-manager.service"
ln -sf /usr/lib/systemd/system/sddm.service "$DM_LINK"

# ── Clean previous build state and build ────────────────────────────────
rm -rf "$WORK_DIR"
mkdir -p "$WORK_DIR" "$OUT_DIR"

mkarchiso -v -w "$WORK_DIR" -o "$OUT_DIR" "$TMP_PROFILE"

echo ""
echo "Build complete!"
echo "ISO location: $OUT_DIR/samios-*.iso"