#!/bin/bash
# PT System Checking 一键更新脚本
# 从 Gitea 下载最新版本并更新服务

set -e

# 颜色输出
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

# 配置变量
GITEA_REPO="https://gitea.service.jazzwhom.top/Passthem/pt-disk-report"
SERVICE_NAME="pt_system_checking"
INSTALL_DIR="/opt/${SERVICE_NAME}"
SYSTEMD_SERVICE="/etc/systemd/system/${SERVICE_NAME}.service"

# 打印信息函数
print_info() {
    echo -e "${GREEN}[INFO]${NC} $1"
}

print_warn() {
    echo -e "${YELLOW}[WARN]${NC} $1"
}

print_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

# 检查是否以 root 运行
check_root() {
    if [ "$EUID" -ne 0 ]; then
        print_error "请使用 root 权限运行此脚本"
        echo "使用方法: sudo bash update.sh"
        exit 1
    fi
}

# 检查服务是否已安装
check_installed() {
    if [ ! -f "${INSTALL_DIR}/${SERVICE_NAME}" ]; then
        print_error "服务未安装，请先运行 install.sh 进行安装"
        exit 1
    fi
    
    if [ ! -f "${SYSTEMD_SERVICE}" ]; then
        print_error "systemd 服务文件不存在，请先运行 install.sh 进行安装"
        exit 1
    fi
}

# 检测系统架构
detect_arch() {
    local arch=$(uname -m)
    case $arch in
        x86_64)
            echo "amd64"
            ;;
        aarch64|arm64)
            echo "arm64"
            ;;
        *)
            print_error "不支持的架构: $arch"
            exit 1
            ;;
    esac
}

# 获取当前版本
get_current_version() {
    if [ -f "${INSTALL_DIR}/${SERVICE_NAME}" ]; then
        local version=$("${INSTALL_DIR}/${SERVICE_NAME}" --version 2>/dev/null | grep -oP 'v\K[0-9.]+' || echo "未知")
        echo "$version"
    else
        echo "未安装"
    fi
}

# 获取最新版本
get_latest_version() {
    local version=$(curl -s "${GITEA_REPO}/releases" | grep -oP 'releases/tag/v\K[0-9.]+' | head -1)
    if [ -z "$version" ]; then
        version="0.1.0"
        print_warn "无法自动获取版本，使用默认版本 ${version}" >&2
    fi
    echo "$version"
}

# 下载二进制文件
download_binary() {
    local arch=$1
    local version=$2
    local binary_name="${SERVICE_NAME}-${arch}"
    local download_url="${GITEA_REPO}/releases/download/v${version}/${binary_name}"
    
    print_info "下载 ${arch} 架构的二进制文件..."
    print_info "下载地址: ${download_url}"
    
    if ! curl -L -f -o "/tmp/${binary_name}" "${download_url}"; then
        print_error "下载失败，请检查版本号和网络连接"
        print_info "尝试的 URL: ${download_url}"
        exit 1
    fi
    
    chmod +x "/tmp/${binary_name}"
    print_info "下载完成"
}

# 备份当前版本
backup_current() {
    local backup_file="${INSTALL_DIR}/${SERVICE_NAME}.backup"
    
    if [ -f "${INSTALL_DIR}/${SERVICE_NAME}" ]; then
        print_info "备份当前版本..."
        cp "${INSTALL_DIR}/${SERVICE_NAME}" "${backup_file}"
        print_info "备份保存至: ${backup_file}"
    fi
}

# 恢复备份
restore_backup() {
    local backup_file="${INSTALL_DIR}/${SERVICE_NAME}.backup"
    
    if [ -f "${backup_file}" ]; then
        print_warn "恢复备份版本..."
        cp "${backup_file}" "${INSTALL_DIR}/${SERVICE_NAME}"
        chmod +x "${INSTALL_DIR}/${SERVICE_NAME}"
        print_info "已恢复到备份版本"
    fi
}

# 更新服务
update_service() {
    local arch=$1
    local binary_name="${SERVICE_NAME}-${arch}"
    
    print_info "更新服务..."
    
    # 停止服务
    if systemctl is-active --quiet "${SERVICE_NAME}"; then
        print_info "停止服务..."
        systemctl stop "${SERVICE_NAME}"
    fi
    
    # 替换二进制文件
    cp "/tmp/${binary_name}" "${INSTALL_DIR}/${SERVICE_NAME}"
    chmod +x "${INSTALL_DIR}/${SERVICE_NAME}"
    
    print_info "服务更新完成"
}

# 启动服务
start_service() {
    print_info "启动服务..."
    
    systemctl start "${SERVICE_NAME}"
    
    sleep 2
    
    if systemctl is-active --quiet "${SERVICE_NAME}"; then
        print_info "服务启动成功！"
        echo ""
        print_info "常用命令:"
        echo "  查看状态: systemctl status ${SERVICE_NAME}"
        echo "  查看日志: journalctl -u ${SERVICE_NAME} -f"
        echo "  停止服务: systemctl stop ${SERVICE_NAME}"
        echo "  重启服务: systemctl restart ${SERVICE_NAME}"
    else
        print_error "服务启动失败，正在恢复备份..."
        restore_backup
        systemctl start "${SERVICE_NAME}"
        
        if systemctl is-active --quiet "${SERVICE_NAME}"; then
            print_info "已恢复到备份版本"
        else
            print_error "恢复失败，请查看日志:"
            echo "  journalctl -u ${SERVICE_NAME} -n 50"
        fi
        exit 1
    fi
}

# 主函数
main() {
    echo ""
    print_info "=== PT System Checking 一键更新脚本 ==="
    echo ""
    
    check_root
    check_installed
    
    # 检测架构
    ARCH=$(detect_arch)
    print_info "检测到系统架构: ${ARCH}"
    
    # 获取版本信息
    CURRENT_VERSION=$(get_current_version)
    print_info "当前版本: ${CURRENT_VERSION}"
    
    print_info "获取最新版本信息..."
    LATEST_VERSION=$(get_latest_version)
    print_info "最新版本: v${LATEST_VERSION}"
    
    # 版本比较
    if [ "$CURRENT_VERSION" == "$LATEST_VERSION" ]; then
        print_info "已是最新版本，无需更新"
        exit 0
    fi
    
    echo ""
    print_warn "即将从 v${CURRENT_VERSION} 更新到 v${LATEST_VERSION}"
    
    # 检查是否为非交互模式
    if [ -t 0 ]; then
        read -p "是否继续？(y/n): " confirm
        if [[ ! $confirm =~ ^[Yy]$ ]]; then
            print_warn "取消更新"
            exit 0
        fi
    else
        print_info "检测到非交互模式，自动继续更新"
    fi
    
    echo ""
    
    # 备份当前版本
    backup_current
    
    # 下载新版本
    download_binary "${ARCH}" "${LATEST_VERSION}"
    
    # 更新服务
    update_service "${ARCH}"
    
    # 启动服务
    start_service
    
    # 清理临时文件
    rm -f "/tmp/${SERVICE_NAME}-${ARCH}"
    
    echo ""
    print_info "更新完成！版本: v${LATEST_VERSION}"
}

# 运行主函数
main "$@"