#!/usr/bin/env bash
# build-rootfs.sh — overlay del workspace sobre una imagen base.
#
# Inputs:
#   $1 — path al rootfs (directorio montado o chroot pre-existente)
#   $2 — path opcional a Card Semilla custom (.k o .json)
#
# Output: el rootfs queda con /init → ente-zero, binarios en
# /usr/local/bin, y la Semilla en /ente/seed.card.k.

set -euo pipefail

ROOTFS="${1:-}"
SEED_CARD="${2:-}"

if [[ -z "$ROOTFS" || ! -d "$ROOTFS" ]]; then
    echo "Uso: $0 <rootfs-dir> [seed-card-path]" >&2
    exit 1
fi

WORKSPACE="$(cd "$(dirname "$0")/.." && pwd)"
echo "Workspace: $WORKSPACE"
echo "Rootfs:    $ROOTFS"

# 1. Build release
echo "==> cargo build --workspace --release"
cd "$WORKSPACE"
cargo build --workspace --release

# 2. Copia binarios
echo "==> copiando binarios a $ROOTFS/usr/local/bin/"
mkdir -p "$ROOTFS/usr/local/bin"
BINS=(
    ente-zero
    ente-logind-compat
    ente-hostnamed-compat
    ente-timedated-compat
    ente-localed-compat
    ente-journald-compat
    ente-resolved-compat
    ente-polkit-compat
    ente-machined-compat
    ente-echo
    ente-journalctl
)
for bin in "${BINS[@]}"; do
    src="target/release/$bin"
    if [[ ! -x "$src" ]]; then
        echo "WARN: $src no existe, skip" >&2
        continue
    fi
    cp "$src" "$ROOTFS/usr/local/bin/"
    echo "  + $bin"
done

# brainctl viene del example
if [[ -x "target/release/examples/brainctl" ]]; then
    cp "target/release/examples/brainctl" "$ROOTFS/usr/local/bin/"
    echo "  + brainctl (example)"
fi
if [[ -x "target/release/examples/busctl" ]]; then
    cp "target/release/examples/busctl" "$ROOTFS/usr/local/bin/ente-busctl"
    echo "  + ente-busctl (example, renombrado para no chocar con systemd-busctl)"
fi

# 3. Backup del init original
if [[ -e "$ROOTFS/sbin/init" && ! -L "$ROOTFS/sbin/init" ]]; then
    if [[ ! -e "$ROOTFS/sbin/init.systemd" ]]; then
        echo "==> backup /sbin/init → /sbin/init.systemd"
        mv "$ROOTFS/sbin/init" "$ROOTFS/sbin/init.systemd"
    fi
fi

# 4. /init y /sbin/init apuntan a ente-zero
echo "==> /init → ente-zero"
ln -sf /usr/local/bin/ente-zero "$ROOTFS/init"
ln -sf /usr/local/bin/ente-zero "$ROOTFS/sbin/init"

# 5. Card Semilla
mkdir -p "$ROOTFS/ente"
if [[ -n "$SEED_CARD" && -f "$SEED_CARD" ]]; then
    cp "$SEED_CARD" "$ROOTFS/ente/seed.card.k"
    echo "==> Semilla custom: $SEED_CARD"
else
    cp "$WORKSPACE/docs/seed-gnome-test.k" "$ROOTFS/ente/seed.card.k" 2>/dev/null \
        || echo "WARN: docs/seed-gnome-test.k no existe; ente-zero sintetizará dev seed"
fi

# 6. Mascara servicios systemd que vamos a sustituir
echo "==> systemctl mask de servicios sustituidos (si systemd presente)"
chroot "$ROOTFS" systemctl mask \
    systemd-logind.service \
    systemd-hostnamed.service \
    systemd-timedated.service \
    systemd-localed.service \
    systemd-journald.service \
    systemd-resolved.service \
    systemd-machined.service \
    polkit.service \
    2>/dev/null || echo "  (chroot mask falló — OK si la imagen no tiene systemd)"

echo "==> rootfs listo en $ROOTFS"
echo
echo "Próximo paso:"
echo "  scripts/run-vm.sh <imagen-base.qcow2>"