#!/bin/bash

set -e

# --------------------------------------------
# 参数解析：必须指定 config.json 路径
# --------------------------------------------
CONFIG_PATH=""

while [[ $# -gt 0 ]]; do
    case "$1" in
        -c|--config)
            CONFIG_PATH="$2"
            shift 2
            ;;
        *)
            echo "❌ 未知参数: $1"
            exit 1
            ;;
    esac
done

if [[ -z "$CONFIG_PATH" ]]; then
    echo "❌ 必须使用 -c <config.json 路径>"
    echo "示例: sudo ./install_mdns.sh -c /home/aiec/demo/config.json"
    exit 1
fi

if [[ ! -f "$CONFIG_PATH" ]]; then
    echo "❌ 找不到配置文件:"
    echo "    $CONFIG_PATH"
    exit 1
fi

echo "📌 使用配置文件: $CONFIG_PATH"


# --------------------------------------------
# 1. 安装 avahi 组件
# --------------------------------------------
echo "=== 安装 Avahi 相关 deb 包 ==="
sudo dpkg -i avahi-daemon_*.deb avahi-utils_*.deb avahi-autoipd_*.deb libnss-mdns_*.deb || true
sudo apt --fix-broken install -y


echo "=== 启动 & 启用 avahi-daemon ==="
sudo systemctl enable avahi-daemon || true
sudo systemctl restart avahi-daemon


# --------------------------------------------
# 2. 安装 update_mdns.sh（核心逻辑）
# --------------------------------------------
echo "=== 写入 /usr/local/bin/update_mdns.sh ==="

sudo mkdir -p /usr/local/bin

sudo tee /usr/local/bin/update_mdns.sh >/dev/null <<'EOF'
#!/bin/bash

CONFIG="@CONFIG_PATH@"
TRIGGER="/run/update_mdns_request"

# --------------- 读取 device_no ---------------
DEVICE_NO=$(grep -oP '"device_no"\s*:\s*"\K[^"]+' "$CONFIG")

# 若触发文件存在，则优先使用触发文件内容
if [[ -f "$TRIGGER" ]]; then
    FILE_VALUE=$(tr -d '\n' < "$TRIGGER")
    if [[ -n "$FILE_VALUE" ]]; then
        DEVICE_NO="$FILE_VALUE"
    fi
fi

if [[ -z "$DEVICE_NO" ]]; then
    echo "[update_mdns] 未找到有效 device_no"
    exit 1
fi

echo "[update_mdns] 更新 hostname = $DEVICE_NO"

# --------------- 设置 hostname ---------------
hostnamectl set-hostname "$DEVICE_NO"

# 修复 /etc/hosts
if grep -q "^127.0.1.1" /etc/hosts; then
    sed -i "s/^127.0.1.1.*/127.0.1.1    $DEVICE_NO/" /etc/hosts
else
    echo "127.0.1.1    $DEVICE_NO" >> /etc/hosts
fi

# --------------- 更新 Avahi 服务 ---------------
mkdir -p /etc/avahi/services
tee /etc/avahi/services/webconfig.service >/dev/null <<EOF2
<?xml version="1.0" standalone='no'?>
<!DOCTYPE service-group SYSTEM "avahi-service.dtd">

<service-group>
  <name replace-wildcards="yes">%h Config Page</name>

  <service>
    <type>_http._tcp</type>
    <port>18080</port>
  </service>
</service-group>
EOF2

systemctl restart avahi-daemon

# 删除触发文件，避免重复触发
rm -f "$TRIGGER"

EOF

sudo chmod +x /usr/local/bin/update_mdns.sh

# 用真实 CONFIG_PATH 替换脚本中的占位符
sudo sed -i "s|@CONFIG_PATH@|$CONFIG_PATH|g" /usr/local/bin/update_mdns.sh



# --------------------------------------------
# 3. 安装 systemd service
# --------------------------------------------
echo "=== 创建 update-mdns.service ==="

sudo tee /etc/systemd/system/update-mdns.service >/dev/null <<EOF
[Unit]
Description=Update hostname & mDNS when device_no changed

[Service]
Type=oneshot
ExecStart=/usr/local/bin/update_mdns.sh
EOF



# --------------------------------------------
# 4. 安装 systemd path watcher
# --------------------------------------------
echo "=== 创建 update-mdns.path ==="

sudo tee /etc/systemd/system/update-mdns.path >/dev/null <<EOF
[Unit]
Description=Watch for mDNS update request

[Path]
PathExists=/run/update_mdns_request

[Install]
WantedBy=multi-user.target
EOF


sudo systemctl daemon-reload
sudo systemctl enable update-mdns.path
sudo systemctl start update-mdns.path


echo ""
echo "============================================="
echo "mDNS 自动更新机制安装完成！🎉"
echo "配置文件路径：$CONFIG_PATH"
echo ""
echo "当 C++ 程序写入： /run/update_mdns_request"
echo "内容 = 新设备号，例如： KL777"
echo "系统会立即更新："
echo "  • hostname"
echo "  • /etc/hosts"
echo "  • avahi 广播名字（xxx.local）"
echo "============================================="