#!/usr/bin/env bash
# 在已建好 Android 分区的盘上，补完 mkfs/super/boot/ESP 四步。
# 不建分区、不动 Windows 分区、不改 p1 的 PARTLABEL。
#
# 用法: sudo ./install-alongside.sh <release-dir>
#
# 前提：已用 installer-lib.sh 的 gk3_apply --mode alongside 建好 p5~p10。
set -euo pipefail
# ── 工具函数 ──────────────────────────────────────────────────────────────
die() { echo "!! $*" >&2; exit 1; }
say() { echo; echo "══ $*"; }
need_root() { [ "$(id -u)" = 0 ] || die "需要 root"; }
need_cmd() { command -v "$1" >/dev/null || die "缺工具: $1"; }
need_file() { [ -f "$REL/$1" ] || die "release 目录里缺 $1"; }

# ── 参数 ──────────────────────────────────────────────────────────────────
REL="${1:-}"
[ -n "$REL" ] || { echo "用法: $0 <release-dir>" >&2; exit 1; }
[ -d "$REL" ] || { echo "目录不存在: $REL" >&2; exit 1; }
REL=$(realpath "$REL" 2>/dev/null || readlink -f "$REL" 2>/dev/null || echo "$REL")
[ -d "$REL" ] || die "无法解析 release 目录路径: $REL"

MID="${GK3_MACHINE_ID:-8a29534fa802480d9fbb71aa18c01d7b}"
DISK="${DISK:-/dev/nvme0n1}"
ESP="${ESP:-${DISK}p1}"
ESP_MNT="${ESP_MNT:-/mnt/winesp}"

# 根据 PARTLABEL 查找分区，找不到就报错退出
find_part() {
    local label="$1"
    local devs
    devs=$(blkid -t PARTLABEL="$label" -o device 2>/dev/null)
    local count
    count=$(echo "$devs" | grep -c .)
    [ "$count" -ge 1 ] || die "找不到 PARTLABEL 为 '$label' 的分区"
    [ "$count" -eq 1 ] || die "PARTLABEL '$label' 匹配到多个分区：$devs，请先清理"
    echo "$devs"
}

P_MISC=$(find_part misc)
P_META=$(find_part metadata)
P_BOOT_A=$(find_part boot_a)
P_BOOT_B=$(find_part boot_b)
P_SUPER=$(find_part super)
P_USERDATA=$(find_part userdata)

# 退出时保证 ESP 已卸载
cleanup() {
    if mountpoint -q "$ESP_MNT"; then
        sync
        umount "$ESP_MNT" 2>/dev/null || \
        umount -l "$ESP_MNT" 2>/dev/null || \
        echo "!! 无法卸载 $ESP_MNT" >&2
    fi
}
trap cleanup EXIT

# ── 前置检查 ──────────────────────────────────────────────────────────────
need_root
for t in sgdisk partprobe mkfs.ext4 simg2img dd od; do need_cmd "$t"; done

say "release 目录: $REL"
for f in super.img boot.img Image gaokun3.dtb ramdisk.img systemd-bootaa64.efi; do
    need_file "$f"
    printf "  ✅ %-24s %s\n" "$f" "$(du -h "$REL/$f" | cut -f1)"
done

say "目标分区"
for p in "$P_MISC" "$P_META" "$P_BOOT_A" "$P_BOOT_B" "$P_SUPER" "$P_USERDATA"; do
    [ -b "$p" ] || die "$p 不存在——先跑 gk3_apply --mode alongside 建分区"
    printf "  ✅ %-20s %s\n" "$p" "$(lsblk -no SIZE "$p" | tr -d ' ')"
done

say "ESP"
[ -b "$ESP" ] || die "$ESP 不存在"

# 根文件系统不能在内置盘上
case "$(findmnt -n -o SOURCE / 2>/dev/null)" in
    "$DISK"*) die "根文件系统在 $DISK 上，必须从 U 盘/Live 启动" ;;
esac

say "即将执行以下破坏性操作，请核对目标设备："
echo "  metadata : $P_META"
echo "  userdata : $P_USERDATA"
echo "  misc     : $P_MISC"
echo "  super    : $P_SUPER"
echo "  boot_a   : $P_BOOT_A"
echo "  boot_b   : $P_BOOT_B"
echo "  ESP      : $ESP"
echo
echo "  ⚠️  metadata / userdata 将被格式化，misc 将被清零，boot_a/b 和 super 将被覆盖。"
read -r -p "确认继续？(输入 yes 继续，其他任意键退出) " ans
[ "$ans" = "yes" ] || die "已取消"

# ── 步骤 1: mkfs + misc 清零（幂等，但会清 userdata，先确认）──────────────
say "步骤 1/4: 文件系统"

# metadata 和 userdata 是否已经格式化
META_FS=$(lsblk -no FSTYPE "$P_META" | tr -d ' ')
DATA_FS=$(lsblk -no FSTYPE "$P_USERDATA" | tr -d ' ')

if [ "$META_FS" = "ext4" ] && [ "$DATA_FS" = "ext4" ]; then
    echo "  p6/p10 已是 ext4。"
    read -r -p "  重新 mkfs 会清空 userdata，继续？(yes/no) " ans
    [ "$ans" = "yes" ] || die "已取消"
fi

mkfs.ext4 -q -F -L metadata "$P_META"
mkfs.ext4 -q -F -L userdata "$P_USERDATA"
dd if=/dev/zero of="$P_MISC" bs=1M count=4 status=none
sync
echo "  ✅ metadata / userdata / misc"

# ── 步骤 2: super.img ─────────────────────────────────────────────────────
say "步骤 2/4: super.img"
MAGIC=$(od -A n -t x1 -N 4 "$REL/super.img" | tr -d ' \n')
if [ "$MAGIC" = "3aff26ed" ]; then
    echo "  sparse → simg2img"
	# simg2img 分支
	simg2img "$REL/super.img" "$P_SUPER"
	# 验证：simg2img 的输出大小应该等于 super 分区的容量（或至少不小于某个下限）
	SUPER_SIZE=$(blockdev --getsize64 "$P_SUPER")
	IMG_SIZE=$(wc -c < "$REL/super.img")
	echo "  super 分区容量 ${SUPER_SIZE} 字节，源镜像 ${IMG_SIZE} 字节"
else
    echo "  raw → dd"
    dd if="$REL/super.img" of="$P_SUPER" bs=4M conv=fsync status=progress
fi
sync
LP=$(dd if="$P_SUPER" bs=1 skip=4096 count=4 2>/dev/null | od -An -tx1 | tr -d ' \n')
[ "$LP" = "67446c61" ] || die "super 的 LP 元数据不对（得到 '$LP'）"
echo "  ✅ LP 元数据 67446c61"

# ── 步骤 3: boot_a / boot_b ───────────────────────────────────────────────
H_SRC=$(dd if="$REL/boot.img" bs=8 count=1 2>/dev/null)
[ "$H_SRC" = "ANDROID!" ] || die "源 boot.img 头部不是 ANDROID!（得到 '$H_SRC'）"
echo "  ✅ 源 boot.img 头部验证通过"
for p in "$P_BOOT_A" "$P_BOOT_B"; do
    dd if="$REL/boot.img" of="$p" bs=4M conv=fsync status=none
    # 写入后读回验证
    H=$(dd if="$p" bs=8 count=1 2>/dev/null)
    [ "$H" = "ANDROID!" ] || die "$p 头部不是 ANDROID!（得到 '$H'）"
    echo "  ✅ $p"
done
sync

# ── 步骤 4: ESP ───────────────────────────────────────────────────────────
say "步骤 4/4: ESP"

mkdir -p "$ESP_MNT"
mount "$ESP" "$ESP_MNT" || die "挂载 $ESP 失败"
findmnt "$ESP_MNT" >/dev/null || die "$ESP_MNT 没挂上"
echo "  已挂载 $ESP → $ESP_MNT"

# 挂载后立即计算所需空间
REQUIRED_MIB=0
for f in systemd-bootaa64.efi Image gaokun3.dtb ramdisk.img; do
    size=$(wc -c < "$REL/$f")
    # 所有文件都写两份（systemd-boot 写两份，内核相关写 slot_a/b 两份）
    REQUIRED_MIB=$(( REQUIRED_MIB + (size * 2 + 1048575) / 1048576 ))
done
# 再加 10 MiB 余量
REQUIRED_MIB=$(( REQUIRED_MIB + 10 ))

FREE_MIB=$(df -m "$ESP_MNT" | awk 'NR==2{print $4}')
echo "  ESP 空闲 ${FREE_MIB} MiB，预计需要 ${REQUIRED_MIB} MiB"
[ "$FREE_MIB" -ge "$REQUIRED_MIB" ] || die "ESP 空间不足"

# 目录
mkdir -p "$ESP_MNT/EFI/systemd" "$ESP_MNT/loader/entries"
mkdir -p "$ESP_MNT/$MID/android/slot_a" "$ESP_MNT/$MID/android/slot_b"

# systemd-boot 本体
cp "$REL/systemd-bootaa64.efi" "$ESP_MNT/EFI/systemd/systemd-bootaa64.efi"
echo "  ✅ EFI/systemd/systemd-bootaa64.efi"

# 回落路径：只在备份不存在时备份
if [ -f "$ESP_MNT/EFI/Boot/bootaa64.efi" ] && \
   [ ! -f "$ESP_MNT/EFI/Boot/bootaa64.efi.bak-windows" ]; then
    cp "$ESP_MNT/EFI/Boot/bootaa64.efi" "$ESP_MNT/EFI/Boot/bootaa64.efi.bak-windows"
    echo "  ✅ 已备份 Windows 回落路径 → bootaa64.efi.bak-windows"
elif [ -f "$ESP_MNT/EFI/Boot/bootaa64.efi.bak-windows" ]; then
    echo "  ⏭  备份已存在，跳过"
fi
cp "$REL/systemd-bootaa64.efi" "$ESP_MNT/EFI/Boot/bootaa64.efi"
echo "  ✅ EFI/Boot/bootaa64.efi ← systemd-boot"

# 内核/DTB/ramdisk
for slot in a b; do
    cp "$REL/Image"       "$ESP_MNT/$MID/android/slot_$slot/Image"
    cp "$REL/gaokun3.dtb" "$ESP_MNT/$MID/android/slot_$slot/gaokun3.dtb"
    cp "$REL/ramdisk.img" "$ESP_MNT/$MID/android/slot_$slot/ramdisk.img"
done
echo "  ✅ 内核/DTB/ramdisk → slot_a, slot_b"

# BLS 条目
for slot in a b; do
    cat > "$ESP_MNT/loader/entries/$MID-android-$slot.conf" <<EOF
title      Android — slot _$slot
version    gaokun3-slot-$slot
sort-key   zandroid$slot
options    androidboot.hardware=gaokun3 androidboot.boot_devices=soc@0/1c20000.pcie androidboot.selinux=permissive androidboot.veritymode=disabled androidboot.flash.locked=0 androidboot.verifiedbootstate=orange firmware_class.path=/vendor/firmware/ init=/init printk.devkmsg=on deferred_probe_timeout=10 console=tty0 iommu.passthrough=0 iommu.strict=0 clk_ignore_unused pd_ignore_unused arm64.nopauth efi=noruntime fbcon=rotate:1 usbhid.quirks=0x12d1:0x10b8:0x20000000 androidboot.slot_suffix=_$slot
linux      /$MID/android/slot_$slot/Image
devicetree /$MID/android/slot_$slot/gaokun3.dtb
initrd     /$MID/android/slot_$slot/ramdisk.img
EOF
done
echo "  ✅ BLS 条目 android-a / android-b"

# loader.conf：不写 default，让用户手选
cat > "$ESP_MNT/loader/loader.conf" <<'EOF'
default @saved
timeout 5
console-mode keep
editor no
EOF
echo "  ✅ loader.conf"

sync
umount "$ESP_MNT"
trap - EXIT
echo
echo "完成。重启后 systemd-boot 菜单会列出 slot_a / slot_b / Windows。"