#!/usr/bin/env bash
# Прошивка eMMC на X96Q — запускать на приставке под root
# Usage: sudo ./flash-emmc.sh [образ.img.xz]
set -euo pipefail

DIR="$(cd "$(dirname "$0")" && pwd)"
UBOOT="${UBOOT:-${DIR}/../output/u-boot-custom.bin}"
IMG_XZ="${1:-}"

if [[ $EUID -ne 0 ]]; then
  echo "Запустите: sudo $0 [образ.img.xz]"
  exit 1
fi

if [[ -z "$IMG_XZ" ]]; then
  shopt -s nullglob
  imgs=( "$DIR"/*.img.xz )
  if [[ ${#imgs[@]} -eq 0 ]]; then
    echo "Нет .img.xz в $DIR"
    exit 1
  elif [[ ${#imgs[@]} -eq 1 ]]; then
    IMG_XZ="${imgs[0]}"
  else
    echo "Несколько образов — укажите явно:"
    ls -lh "${imgs[@]}"
    exit 1
  fi
fi

[[ -f "$IMG_XZ" ]] || { echo "Нет файла: $IMG_XZ"; exit 1; }
[[ -f "$UBOOT" ]] || { echo "Нет $UBOOT"; exit 1; }

EMMC=/dev/mmcblk2
BOOT0=/dev/mmcblk2boot0
BOOT1=/dev/mmcblk2boot1

[[ -b "$EMMC" ]] || { echo "eMMC не найден: $EMMC"; exit 1; }

unlock_boot() {
  local ro
  for part in boot0 boot1; do
    ro="/sys/block/mmcblk2${part}/force_ro"
    [[ -w "$ro" ]] || continue
    echo 0 >"$ro"
    echo "mmcblk2${part}: force_ro=$(cat "$ro")"
  done
}

echo "=== eMMC flash (X96Q) ==="
echo "Образ:  $IMG_XZ ($(du -h "$IMG_XZ" | cut -f1))"
echo "U-Boot: $UBOOT"
echo "Цель:   $EMMC + $BOOT0 + $BOOT1"
lsblk -o NAME,SIZE,TYPE,MOUNTPOINT 2>/dev/null | grep -E 'mmcblk|NAME' || lsblk

echo "[1/4] Запись образа на $EMMC ..."
xz -dc "$IMG_XZ" | dd of="$EMMC" bs=4M status=progress conv=fsync
sync

echo "[2/4] U-Boot → user area @ 8 KiB ..."
dd if="$UBOOT" of="$EMMC" bs=1024 seek=8 conv=fsync

echo "Разблокировка boot0/boot1 (force_ro) ..."
unlock_boot

echo "[3/4] U-Boot → boot0 ..."
dd if="$UBOOT" of="$BOOT0" bs=1024 conv=fsync

echo "[4/4] U-Boot → boot1 ..."
dd if="$UBOOT" of="$BOOT1" bs=1024 conv=fsync
sync

# Armbian DTB: в образе sun50i-h313-x96q-lpddr3.dtb, не v1.3
MNT="/tmp/emmc-fix"
mkdir -p "$MNT"
if mount "${EMMC}p1" "$MNT"; then
  ENV="${MNT}/boot/armbianEnv.txt"
  DTB="${MNT}/boot/dtb/allwinner"
  if [[ -f "$ENV" ]]; then
    if grep -q '^fdtfile=' "$ENV"; then
      sed -i 's/^fdtfile=.*/fdtfile=sun50i-h313-x96q-lpddr3.dtb/' "$ENV"
    else
      echo 'fdtfile=sun50i-h313-x96q-lpddr3.dtb' >>"$ENV"
    fi
  fi
  if [[ -d "$DTB" && -f "${DTB}/sun50i-h313-x96q-lpddr3.dtb" ]]; then
    ln -sf sun50i-h313-x96q-lpddr3.dtb "${DTB}/sun50i-h313-x96q-lpddr3-v1.3.dtb"
  fi
  sync
  umount "$MNT"
fi
rmdir "$MNT" 2>/dev/null || true

echo "Готово. Выключите, выньте SD, включите — загрузка с eMMC."