#!/bin/bash
# FTP Server 服务管理脚本
# 用法: ./service-linux.sh {install|uninstall|start|stop|restart|status|enable|disable|logs}

# 配置区域 - 请根据实际路径修改
INSTALL_DIR="/opt/ftp-server"
FTP_EXE="$INSTALL_DIR/ftp-server"
CONFIG_FILE="$INSTALL_DIR/config.json"
SERVICE_NAME="ftp-server"
SERVICE_FILE="/etc/systemd/system/${SERVICE_NAME}.service"
LOG_FILE="$INSTALL_DIR/server.log"
PID_FILE="$INSTALL_DIR/ftp-server.pid"

# 颜色
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
NC='\033[0m'

info()  { echo -e "${GREEN}[信息]${NC} $1"; }
warn()  { echo -e "${YELLOW}[警告]${NC} $1"; }
error() { echo -e "${RED}[错误]${NC} $1"; }

# 检查 root 权限
check_root() {
    if [ "$EUID" -ne 0 ]; then
        error "请使用 root 权限运行此脚本 (sudo ./service-linux.sh ...)"
        exit 1
    fi
}

# 检查可执行文件
check_exe() {
    if [ ! -f "$FTP_EXE" ]; then
        error "找不到 $FTP_EXE"
        error "请先编译: go build -o $FTP_EXE ."
        exit 1
    fi
    if [ ! -x "$FTP_EXE" ]; then
        chmod +x "$FTP_EXE"
    fi
}

# 安装服务
do_install() {
    check_root
    check_exe

    # 创建工作目录
    mkdir -p "$INSTALL_DIR/data"

    info "正在创建 systemd 服务文件..."

    cat > "$SERVICE_FILE" << EOF
[Unit]
Description=FTP Server with Web Management
After=network.target
Wants=network-online.target

[Service]
Type=simple
User=root
Group=root
WorkingDirectory=$INSTALL_DIR
ExecStart=$FTP_EXE -config $CONFIG_FILE
ExecReload=/bin/kill -HUP \$MAINPID
Restart=on-failure
RestartSec=5
LimitNOFILE=65535

# 日志输出到 journalctl
StandardOutput=journal
StandardError=journal
SyslogIdentifier=$SERVICE_NAME

[Install]
WantedBy=multi-user.target
EOF

    # 重载 systemd
    systemctl daemon-reload
    info "服务已安装: $SERVICE_FILE"
    info "使用 '$0 start' 启动服务"
    info "使用 '$0 enable' 设置开机自启"
}

# 卸载服务
do_uninstall() {
    check_root
    info "正在停止服务..."
    systemctl stop "$SERVICE_NAME" 2>/dev/null
    systemctl disable "$SERVICE_NAME" 2>/dev/null

    if [ -f "$SERVICE_FILE" ]; then
        rm -f "$SERVICE_FILE"
        systemctl daemon-reload
        info "服务已卸载"
    else
        warn "服务文件不存在，可能未安装"
    fi
}

# 启动服务
do_start() {
    if [ -f "$SERVICE_FILE" ]; then
        check_root
        systemctl start "$SERVICE_NAME"
        if [ $? -eq 0 ]; then
            info "服务已启动"
            info "  FTP端口: 2121"
            info "  Web管理: http://localhost:8080"
        else
            error "服务启动失败，查看日志: $0 logs"
            exit 1
        fi
    else
        # 前台/后台直接运行
        check_exe
        info "以后台模式启动..."
        cd "$INSTALL_DIR"
        nohup "$FTP_EXE" -config "$CONFIG_FILE" >> "$LOG_FILE" 2>&1 &
        echo $! > "$PID_FILE"
        sleep 1
        if kill -0 $(cat "$PID_FILE" 2>/dev/null) 2>/dev/null; then
            info "服务已启动 (PID: $(cat $PID_FILE))"
            info "  FTP端口: 2121"
            info "  Web管理: http://localhost:8080"
            info "  日志文件: $LOG_FILE"
        else
            error "服务启动失败，查看日志: $LOG_FILE"
            rm -f "$PID_FILE"
            exit 1
        fi
    fi
}

# 停止服务
do_stop() {
    if [ -f "$SERVICE_FILE" ]; then
        check_root
        systemctl stop "$SERVICE_NAME"
        if [ $? -eq 0 ]; then
            info "服务已停止"
        else
            error "服务停止失败"
            exit 1
        fi
    elif [ -f "$PID_FILE" ]; then
        PID=$(cat "$PID_FILE")
        if kill -0 "$PID" 2>/dev/null; then
            kill "$PID"
            sleep 2
            if kill -0 "$PID" 2>/dev/null; then
                kill -9 "$PID"
            fi
            rm -f "$PID_FILE"
            info "服务已停止 (PID: $PID)"
        else
            warn "进程 $PID 已不存在"
            rm -f "$PID_FILE"
        fi
    else
        # 尝试查找进程
        PID=$(pgrep -f "$FTP_EXE")
        if [ -n "$PID" ]; then
            kill "$PID"
            info "服务已停止 (PID: $PID)"
        else
            warn "服务未在运行"
        fi
    fi
}

# 重启服务
do_restart() {
    do_stop
    sleep 2
    do_start
}

# 查看状态
do_status() {
    if [ -f "$SERVICE_FILE" ]; then
        systemctl status "$SERVICE_NAME" --no-pager
    elif [ -f "$PID_FILE" ]; then
        PID=$(cat "$PID_FILE")
        if kill -0 "$PID" 2>/dev/null; then
            info "服务运行中 (PID: $PID)"
        else
            warn "服务未在运行 (PID文件过期)"
            rm -f "$PID_FILE"
        fi
    else
        PID=$(pgrep -f "$FTP_EXE")
        if [ -n "$PID" ]; then
            info "服务运行中 (PID: $PID)"
        else
            warn "服务未在运行"
        fi
    fi
}

# 开机自启
do_enable() {
    check_root
    if [ -f "$SERVICE_FILE" ]; then
        systemctl enable "$SERVICE_NAME"
        info "已设置开机自启"
    else
        error "请先运行 '$0 install' 安装服务"
        exit 1
    fi
}

# 关闭自启
do_disable() {
    check_root
    if [ -f "$SERVICE_FILE" ]; then
        systemctl disable "$SERVICE_NAME"
        info "已关闭开机自启"
    else
        error "服务未安装"
        exit 1
    fi
}

# 查看日志
do_logs() {
    if [ -f "$SERVICE_FILE" ]; then
        journalctl -u "$SERVICE_NAME" -f --no-pager -n 50
    elif [ -f "$LOG_FILE" ]; then
        tail -f "$LOG_FILE"
    else
        warn "没有可用的日志文件"
    fi
}

# 菜单模式
do_menu() {
    while true; do
        echo ""
        echo "========================================"
        echo "  FTP Server 服务管理工具 (Linux)"
        echo "========================================"
        echo ""
        echo "  1. 安装服务 (systemd)"
        echo "  2. 卸载服务"
        echo "  3. 启动服务"
        echo "  4. 停止服务"
        echo "  5. 重启服务"
        echo "  6. 查看服务状态"
        echo "  7. 开机自启 - 开启"
        echo "  8. 开机自启 - 关闭"
        echo "  9. 查看运行日志"
        echo "  0. 退出"
        echo ""
        read -p "请输入选项: " choice

        case $choice in
            1) do_install ;;
            2) do_uninstall ;;
            3) do_start ;;
            4) do_stop ;;
            5) do_restart ;;
            6) do_status ;;
            7) do_enable ;;
            8) do_disable ;;
            9) do_logs ;;
            0) exit 0 ;;
            *) warn "无效选项" ;;
        esac

        read -p "按 Enter 继续..."
    done
}

# 主入口
case "${1:-}" in
    install)   do_install ;;
    uninstall) do_uninstall ;;
    start)     do_start ;;
    stop)      do_stop ;;
    restart)   do_restart ;;
    status)    do_status ;;
    enable)    do_enable ;;
    disable)   do_disable ;;
    logs)      do_logs ;;
    menu|"")   do_menu ;;
    *)
        echo "用法: $0 {install|uninstall|start|stop|restart|status|enable|disable|logs|menu}"
        echo ""
        echo "命令说明:"
        echo "  install   - 安装为 systemd 服务"
        echo "  uninstall - 卸载服务"
        echo "  start     - 启动服务"
        echo "  stop      - 停止服务"
        echo "  restart   - 重启服务"
        echo "  status    - 查看服务状态"
        echo "  enable    - 设置开机自启"
        echo "  disable   - 关闭开机自启"
        echo "  logs      - 查看运行日志 (实时)"
        echo "  menu      - 交互式菜单 (默认)"
        exit 1
        ;;
esac