#!/bin/bash

# 脚本出现错误时立即退出
set -e

# 检查是否以 root 权限运行
if [ "$(id -u)" -ne 0 ]; then
  echo "错误：此脚本需要以 root 权限运行。"
  exit 1
fi

# 定义变量 (可选，但方便维护)
HYSTERIA_VERSION="v2.6.2"
HYSTERIA_BINARY_NAME="hysteria-linux-amd64"
#HYSTERIA_DOWNLOAD_URL="https://github.com/apernet/hysteria/releases/download/app/${HYSTERIA_VERSION}/${HYSTERIA_BINARY_NAME}"
# 如果上面的地址下载慢，可以切换到 gh-proxy
HYSTERIA_DOWNLOAD_URL="https://gh-proxy.com/github.com/apernet/hysteria/releases/download/app/${HYSTERIA_VERSION}/${HYSTERIA_BINARY_NAME}"
HYSTERIA_INSTALL_SCRIPT_URL="https://get.hy2.sh/"
HYSTERIA_CONFIG_DIR="/etc/hysteria"
HYSTERIA_KEY_FILE="${HYSTERIA_CONFIG_DIR}/server.key"
HYSTERIA_CERT_FILE="${HYSTERIA_CONFIG_DIR}/server.crt"
HYSTERIA_CERT_SUBJ="/CN=bing.com" # 你可以按需修改这个CN
CONFIG_DOWNLOAD_URL="http://23.27.28.64:8080/config.yaml"
LOCAL_CONFIG_FILE="config.yaml" # 下载的配置文件名
HYSTERIA_SERVER_CONFIG_FILE="${HYSTERIA_CONFIG_DIR}/config.yaml"
SYSCTL_CONF_FILE="/etc/sysctl.conf"
PRIORITY_CONF_DIR="/etc/systemd/system/hysteria-server.service.d"
PRIORITY_CONF_FILE="${PRIORITY_CONF_DIR}/priority.conf"

# --- 函数定义 ---
check_and_install_deps() {
    echo "===== 0. 检查并安装依赖 ====="
    REQUIRED_CMDS=("curl" "wget" "openssl")
    PACKAGES_TO_INSTALL="curl wget openssl cron ca-certificates"
    NEEDS_INSTALL=false

    for cmd in "${REQUIRED_CMDS[@]}"; do
        if ! command -v "$cmd" &> /dev/null; then
            echo "检测到必需的命令 '$cmd' 未安装。"
            NEEDS_INSTALL=true
            break
        fi
    done

    if [ "$NEEDS_INSTALL" = true ]; then
        echo "正在更新软件包列表并安装必需的软件包..."
        apt-get update
        apt-get install -y ${PACKAGES_TO_INSTALL}
        echo "依赖安装完成。"
    else
        echo "所有必需的依赖项均已安装。"
    fi
}

# --- 脚本主流程 ---
check_and_install_deps

echo
echo "===== 1. 下载 Hysteria 二进制文件 ====="
wget --no-check-certificate -O "${HYSTERIA_BINARY_NAME}" "${HYSTERIA_DOWNLOAD_URL}"
if [ ! -f "${HYSTERIA_BINARY_NAME}" ]; then
    echo "错误：下载 Hysteria 二进制文件失败。"
    exit 1
fi
chmod +x "${HYSTERIA_BINARY_NAME}"
echo "Hysteria 二进制文件下载并设置可执行权限完成。"

echo
echo "===== 2. 使用官方脚本安装 Hysteria (本地模式) ====="
bash <(curl -fsSL "${HYSTERIA_INSTALL_SCRIPT_URL}") --local "./${HYSTERIA_BINARY_NAME}"
echo "Hysteria 安装完成。"

echo
echo "===== 3. 生成自签名证书和密钥 ====="
mkdir -p "${HYSTERIA_CONFIG_DIR}"
openssl req -x509 -nodes -newkey ec:<(openssl ecparam -name prime256v1) \
    -keyout "${HYSTERIA_KEY_FILE}" \
    -out "${HYSTERIA_CERT_FILE}" \
    -subj "${HYSTERIA_CERT_SUBJ}" \
    -days 36500
if [ ! -f "${HYSTERIA_KEY_FILE}" ] || [ ! -f "${HYSTERIA_CERT_FILE}" ]; then
    echo "错误：生成证书或密钥失败。"
    exit 1
fi

echo "等待 hysteria 用户/组创建..."
sleep 2

if id "hysteria" &>/dev/null; then
    chown hysteria:hysteria "${HYSTERIA_KEY_FILE}"
    chown hysteria:hysteria "${HYSTERIA_CERT_FILE}"
    echo "证书和密钥所有权已设置为 hysteria 用户。"
else
    echo "警告：hysteria 用户不存在，无法设置证书所有权。请手动检查。"
fi

echo
echo "===== 4. 下载并复制配置文件 ====="
wget -O "${LOCAL_CONFIG_FILE}" "${CONFIG_DOWNLOAD_URL}"
if [ ! -f "${LOCAL_CONFIG_FILE}" ]; then
    echo "错误：下载配置文件失败。"
    exit 1
fi
cp -f "${LOCAL_CONFIG_FILE}" "${HYSTERIA_SERVER_CONFIG_FILE}"
echo "配置文件已复制到 ${HYSTERIA_SERVER_CONFIG_FILE}"

echo
echo "===== 5. 优化内核网络参数 ====="
# 临时生效
sysctl -w net.core.rmem_max=16777216
sysctl -w net.core.wmem_max=16777216
echo "内核网络参数已临时设置。"

# 持久化，避免重复写入
if ! grep -q "net.core.rmem_max=16777216" "${SYSCTL_CONF_FILE}"; then
    echo "net.core.rmem_max=16777216" >> "${SYSCTL_CONF_FILE}"
    echo "已将 rmem_max 配置写入 ${SYSCTL_CONF_FILE}"
fi
if ! grep -q "net.core.wmem_max=16777216" "${SYSCTL_CONF_FILE}"; then
    echo "net.core.wmem_max=16777216" >> "${SYSCTL_CONF_FILE}"
    echo "已将 wmem_max 配置写入 ${SYSCTL_CONF_FILE}"
fi

echo
echo "===== 6. 优化服务优先级 ====="
mkdir -p "${PRIORITY_CONF_DIR}"
cat > "${PRIORITY_CONF_FILE}" <<EOF
[Service]
CPUSchedulingPolicy=rr
CPUSchedulingPriority=99
EOF
echo "服务优先级配置已创建于 ${PRIORITY_CONF_FILE}"
echo "正在重新加载 systemd 配置..."
systemctl daemon-reload

echo
echo "===== 7. 启动并启用 Hysteria 服务 ====="
systemctl enable hysteria-server.service
systemctl restart hysteria-server.service
echo "Hysteria 服务已设置为开机自启并已启动。"

echo
echo "===== 8. 检查 Hysteria 服务状态 ====="
sleep 2
systemctl status hysteria-server.service --no-pager -l

echo
echo "===== 9. 配置定时重启任务 (Cron Job) ====="
SYSTEMCTL_PATH=$(which systemctl)
BASH_PATH=$(which bash)

if [ -z "${SYSTEMCTL_PATH}" ] || [ -z "${BASH_PATH}" ]; then
    echo "错误：找不到 systemctl 或 bash 命令。无法添加定时任务。"
else
    LOG_FILE="/var/log/hysteria-restart.log"
    # 使用 bash -c 并重定向日志，这是更可靠的方式
    CRON_JOB="30 5 * * * ${BASH_PATH} -c '${SYSTEMCTL_PATH} restart hysteria-server.service' >> ${LOG_FILE} 2>&1"
    
    # 检查任务是否已存在
    if crontab -l 2>/dev/null | grep -qF -- "restart hysteria-server.service"; then
        echo "定时重启任务已存在，无需重复添加。"
    else
        # 添加新任务
        (crontab -l 2>/dev/null; echo "${CRON_JOB}") | crontab -
        if [ $? -eq 0 ]; then
            echo "已成功添加定时重启任务：'${CRON_JOB}'"
            echo "任务执行日志将记录在 ${LOG_FILE}"
        else
            echo "错误：添加定时任务失败。"
        fi
    fi
fi

echo
echo "===== 清理下载的临时文件 ====="
rm -f "./${HYSTERIA_BINARY_NAME}"
rm -f "./${LOCAL_CONFIG_FILE}"
echo "临时文件已清理。"

echo
echo "Hysteria 安装和优化配置脚本执行完毕。"