package middleware

import (
	"blazing/modules/config/model"
	config "blazing/modules/config/service"
	"bufio"
	"context"
	"crypto/rand"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"io"
	"net"
	"strings"
	"sync/atomic"
	"time"

	"github.com/gogf/gf/v2/os/glog"
	"github.com/gogf/gf/v2/util/grand"
	"github.com/lxzan/gws"
	"golang.org/x/crypto/ssh"
)

const (
	PingInterval    = 10 * time.Second
	defaultWorkDir  = "$HOME"           // 全环境兼容
	randomStrLength = 4                 // 缩短随机串长度
	cmdTimeout      = 120 * time.Second // 延长超时（适配Screen安装+下载）
)

// SSHConfig SSH连接配置
type SSHConfig struct {
	ServerIP string `json:"server_ip"`
	Port     string `json:"port"`
	Username string `json:"username"`
	Password string `json:"password"`
}

// WebSSHMessage 消息结构
type WebSSHMessage struct {
	Type    string `json:"type"`
	Payload string `json:"payload"`
}

// TerminalSession 会话结构体（优化通道）
type TerminalSession struct {
	WebSocket  *gws.Conn
	SSHClient  *ssh.Client
	SSHSession *ssh.Session
	Stdin      io.WriteCloser
	Stdout     io.Reader
	Ready      bool
	outputBuf  chan string // 增大通道缓存
	closed     atomic.Bool
}

type ServerHandler struct {
	gws.BuiltinEventHandler
	session *TerminalSession
	model.ServerList
	isinstall uint32
	target    net.Conn
}

// 生成随机文件名
func (s *ServerHandler) generateRandomFileName() string {
	randBytes := make([]byte, randomStrLength)
	_, err := rand.Read(randBytes)
	if err != nil {
		return fmt.Sprintf("logic_%d", time.Now().UnixNano())
	}
	randStr := hex.EncodeToString(randBytes)
	timestamp := time.Now().Format("20060102150405")
	return fmt.Sprintf("logic_%s_%s", timestamp, randStr)
}

// 执行脚本命令
func (s *ServerHandler) executeScript(scriptContent, scriptName string) (string, error) {
	if s.session == nil || s.session.closed.Load() || !s.session.Ready {
		return "", fmt.Errorf("session not ready")
	}

	// 生成临时脚本路径
	scriptPath := fmt.Sprintf("/tmp/%s.sh", scriptName)

	// 直接将脚本内容写入文件
	writeScriptCmd := fmt.Sprintf("cat > '%s' << 'DEPLOYMENT_SCRIPT_END'\n%s\nDEPLOYMENT_SCRIPT_END\n", scriptPath, scriptContent)
	_, err := s.session.Stdin.Write([]byte(writeScriptCmd))
	if err != nil {
		return "", err
	}

	// 等待一会儿确保脚本写入完成
	time.Sleep(time.Second)

	// 设置执行权限
	_, err = s.session.Stdin.Write([]byte(fmt.Sprintf("chmod +x %s\n", scriptPath)))
	if err != nil {
		return "", err
	}

	// 等待权限设置完成
	time.Sleep(time.Second)

	// 执行脚本并将输出发送到WebSocket（在命令中直接删除脚本文件）
	executeCmd := fmt.Sprintf("bash %s 2>&1; rm -f %s\n", scriptPath, scriptPath)
	_, err = s.session.Stdin.Write([]byte(executeCmd))
	if err != nil {
		return "", err
	}

	// 读取脚本执行输出
	output := ""
	done := make(chan bool)

	go func() {
		defer func() {
			if r := recover(); r != nil {
				glog.Error(context.Background(), "Script execution goroutine panic:", r)
			}
		}()

		scanner := bufio.NewScanner(s.session.Stdout)
		for scanner.Scan() {
			line := scanner.Text()

			// 检测到脚本执行完成标记则退出
			if strings.Contains(line, "#SCRIPT_EXECUTION_COMPLETE#") {
				break
			}

			// 忽略一些可能导致连接断开的输出
			if strings.Contains(line, "logout") || strings.Contains(line, "exit") {
				continue
			}

			output += line + "\n"
			s.sendTerminalOutput(s.session.WebSocket, line)
		}
		done <- true
	}()

	// 等待脚本执行完成或超时
	select {
	case <-done:
		return strings.TrimSpace(output), nil
	case <-time.After(cmdTimeout):
		return strings.TrimSpace(output), nil
	}
}
func (s *ServerHandler) executeFullDeployment() error {
	s.sendTerminalOutput(s.session.WebSocket, "开始执行完整自动化部署流程...")

	// 1. 获取并校验下载链接
	fileURL := config.NewServerService().GetFile()
	fileURL = strings.TrimSpace(fileURL)
	if fileURL == "" {
		return fmt.Errorf("下载链接为空")
	}
	// 前置校验：确保链接是合法的URL（包含http/https）
	if !strings.HasPrefix(fileURL, "http://") && !strings.HasPrefix(fileURL, "https://") {
		return fmt.Errorf("下载链接格式非法，缺少http/https协议：%s", fileURL)
	}
	s.sendTerminalOutput(s.session.WebSocket, fmt.Sprintf("【前置检查】有效下载链接：%s", fileURL))

	// 2. 生成目标文件路径
	randomFileName := s.generateRandomFileName()
	remoteExePath := fmt.Sprintf("%s/%s", defaultWorkDir, randomFileName)
	remoteWorkDir := defaultWorkDir
	onlineID := fmt.Sprintf("%d", s.ServerList.OnlineID)
	fixedScreenSession := "logic"

	// 3. 定义部署脚本（给每个%s加唯一标记，方便核对）
	deploymentScriptTpl := `
set -e
set -x

# ===== 检查并安装screen =====
echo "检查Screen是否已安装..."
if command -v screen &> /dev/null; then
    echo "=== Screen已安装，跳过 ==="
else
    echo "=== Screen未安装，开始安装 ==="
    if command -v apt &> /dev/null; then
        apt update -y && apt install -y screen
    elif command -v yum &> /dev/null; then
        yum install -y screen
    elif command -v dnf &> /dev/null; then
        dnf install -y screen
    elif command -v pacman &> /dev/null; then
        pacman -S --noconfirm screen
    else
        echo "❌ 不支持的包管理器，无法安装Screen"
        exit 1
    fi
    command -v screen || { echo "❌ Screen安装失败"; exit 1; }
fi

# ===== 优雅终止logic会话（先等内部程序退出 → 再退screen）=====
echo "===== 优雅终止logic会话 ====="
SCREEN_PID=""
# 你实际使用的screen名称（从日志看是logic）
SCREEN_NAME="%s{screen_name}"  

# 调试开关（如需详细日志，取消set -x注释）
set -o pipefail
export PS4='[DEBUG] ${BASH_SOURCE}:${LINENO} - ${FUNCNAME[0]:+${FUNCNAME[0]}(): }'
# set -x

# 定义：检查PID是否存活的函数
pid_is_alive() {
    local pid=$1
    # 仅检查PID是否存在，不发送信号（最安全的方式）
    if [ -n "$pid" ] && kill -0 "$pid" 2>/dev/null; then
        return 0  # PID存活
    else
        return 1  # PID不存在
    fi
}

# 定义安全的进程检测函数（带超时防卡）
get_inner_procs() {
    local screen_pid=$1
    # 5秒超时，避免pstree卡住
    local procs=$(timeout 5 pstree -p "$screen_pid" 2>/dev/null | grep -oE '\([0-9]+\)' | tr -d '()' | grep -v "$screen_pid" | sort -u)
    # 兜底：pstree失败时用pgrep按screen名称查找
    if [ -z "$procs" ]; then
        procs=$(pgrep -f "SCREEN -S $SCREEN_NAME" 2>/dev/null | grep -v "$screen_pid")
    fi
    echo "$procs"
}

# 1. 检查logic会话是否存在
if screen -ls "$SCREEN_NAME" 2>/dev/null | grep -q -E "[0-9]+\.$SCREEN_NAME"; then
    echo "找到$SCREEN_NAME会话，提取主PID..."
    SCREEN_PID=$(screen -ls "$SCREEN_NAME" | grep -oE '[0-9]+\.'"$SCREEN_NAME" | head -1 | cut -d. -f1)
    
    if [ -z "$SCREEN_PID" ]; then
        echo "⚠️  提取$SCREEN_NAME会话PID失败"
    else
        echo "✅ 提取到$SCREEN_NAME会话主PID：$SCREEN_PID"
        
        # ========== 步骤1：给screen内所有子进程发优雅退出信号 ==========
        echo "给$SCREEN_NAME内所有程序发送优雅退出信号(SIGTERM)..."
        INNER_ALL_PROCS=$(get_inner_procs "$SCREEN_PID")
        
        if [ -n "$INNER_ALL_PROCS" ]; then
            echo "📌 检测到screen内进程列表：$INNER_ALL_PROCS"
            for pid in $INNER_ALL_PROCS; do
                # 发送信号前检查子进程是否存活
                if pid_is_alive "$pid"; then
                    if kill -15 "$pid" 2>/dev/null; then
                        echo "✅ 已给进程$pid发送SIGTERM信号"
                    else
                        echo "⚠️  进程$pid发送信号失败"
                    fi
                else
                    echo "ℹ️  进程$pid已不存在，跳过发送信号"
                fi
            done
        else
            echo "ℹ️  未检测到$SCREEN_NAME内的子进程"
        fi

        # 兜底：给screen内Shell发送exit指令
        echo "给screen内Shell发送exit指令（兜底）..."
        screen -S "$SCREEN_NAME" -p 0 -X stuff $'exit\n' 2>/dev/null
        sleep 1
        
        # ========== 步骤2：循环等待内部程序退出（防卡优化） ==========
        echo "开始循环等待$SCREEN_NAME内部所有程序退出（最大60秒）..."
        WAIT_COUNT=0
        MAX_WAIT_SECONDS=60
        INNER_PROC_EXIST=true
        
        while [ "$INNER_PROC_EXIST" = true ] && [ $WAIT_COUNT -lt $MAX_WAIT_SECONDS ]; do
            INNER_PROCS=$(get_inner_procs "$SCREEN_PID")
            
            # 强制退出条件：即使进程检测失败也不卡住
            if [ -z "$INNER_PROCS" ]; then
                INNER_PROC_EXIST=false
                echo "✅ $SCREEN_NAME内部所有程序已退出（或进程检测完成）"
            else
                sleep 1
                WAIT_COUNT=$((WAIT_COUNT + 1))
                
                # 每5秒输出状态
                if [ $((WAIT_COUNT % 5)) -eq 0 ]; then
                    ELAPSED=$WAIT_COUNT
                    echo "⏳ 等待中...残留进程：$INNER_PROCS（已等$ELAPSED秒，剩余$((MAX_WAIT_SECONDS - ELAPSED))秒）"
                fi
            fi
        done
        
        # 超时提示
        if [ "$INNER_PROC_EXIST" = true ]; then
            echo "⚠️  等待超时（60秒），$SCREEN_NAME内部程序仍未退出"
            echo "📌 残留进程PID：$INNER_PROCS"
        fi
        
        # ========== 步骤3：退出screen会话（核心修复：避免kill卡住） ==========
        if [ "$INNER_PROC_EXIST" = false ]; then
            echo "内部程序已退出，开始退出$SCREEN_NAME会话..."
            # 第一步：尝试正常退出screen会话
            if screen -S "$SCREEN_NAME" -X quit 2>/dev/null; then
                echo "✅ $SCREEN_NAME会话已通过screen -X quit退出"
            else
                echo "ℹ️  screen -X quit执行失败（会话可能已消失），检查PID是否存活..."
                # 第二步：仅当PID存活时，才执行kill，且加超时
                if pid_is_alive "$SCREEN_PID"; then
                    echo "📌 PID $SCREEN_PID 仍存活，尝试kill终止（5秒超时）..."
                    timeout 5 kill -15 "$SCREEN_PID" 2>/dev/null
                    if [ $? -eq 0 ]; then
                        echo "✅ 已给screen主进程$SCREEN_PID发送SIGTERM信号"
                    else
                        echo "⚠️  kill $SCREEN_PID 失败（超时/进程不存在）"
                    fi
                else
                    echo "ℹ️  PID $SCREEN_PID 已不存在，跳过kill操作"
                fi
            fi
            sleep 2
        else
            echo "⚠️  内部程序未完全退出，跳过退出screen会话"
        fi
        
        # 最终验证
        if screen -ls "$SCREEN_NAME" 2>/dev/null | grep -q -E "[0-9]+\.$SCREEN_NAME"; then
            echo "❌ $SCREEN_NAME会话最终仍未退出"
        else
            echo "✅ $SCREEN_NAME会话已完全退出"
        fi
    fi
else
    echo "=== 未找到$SCREEN_NAME会话，跳过终止 ==="
fi

# 关闭调试
# set +x

# ===== 准备下载目录 =====
echo "创建工作目录：%s{work_dir}"
mkdir -p "%s{work_dir}" || { echo "❌ 创建目录失败"; exit 1; }

# ===== 下载程序 =====
echo "===== 开始下载程序 ====="
echo "下载链接：%s{file_url}"
echo "目标路径：%s{exe_path}"

# 删除旧文件
if [ -f "%s{exe_path}" ]; then
    echo "删除旧文件：%s{exe_path}"
    rm -f "%s{exe_path}"
fi

# ===== 准备下载目录 =====
echo "创建工作目录：%s{work_dir}"
mkdir -p "%s{work_dir}" || { echo "❌ 创建目录失败"; exit 1; }

# ===== 下载程序 =====
echo "===== 开始下载程序 ====="
echo "下载链接：%s{file_url}"
echo "目标路径：%s{exe_path}"

# 删除旧文件（关键修复：这里要判断目标路径，不是下载链接）
if [ -f "%s{exe_path}" ]; then
    echo "删除旧文件：%s{exe_path}"
    rm -f "%s{exe_path}"
fi

echo "开始下载..."
DOWNLOAD_SUCCESS=0
if command -v wget >/dev/null 2>&1; then
    # 正确格式：wget -O 目标路径 下载链接
    wget --no-check-certificate --timeout=10 --tries=2 -O "%s{exe_path}" "%s{file_url}"
    DOWNLOAD_SUCCESS=$?
elif command -v curl >/dev/null 2>&1; then
    # 正确格式：curl -o 目标路径 下载链接
    curl -L --connect-timeout 10 --max-time 30 -o "%s{exe_path}" "%s{file_url}"
    DOWNLOAD_SUCCESS=$?
else
    echo "❌ 无wget/curl，无法下载"
    exit 1
fi

if [ $DOWNLOAD_SUCCESS -ne 0 ]; then
    echo "❌ 下载失败，退出码：$DOWNLOAD_SUCCESS"
    exit 1
fi

# 验证文件
if [ -f "%s{exe_path}" ] && [ -s "%s{exe_path}" ]; then
    echo "=== 文件下载完成 ==="
    ls -la "%s{exe_path}"
    # 检查文件大小（至少1KB）
    FILE_SIZE=$(stat -c%s "%s{exe_path}" 2>/dev/null || stat -f%z "%s{exe_path}" 2>/dev/null)
    [ "$FILE_SIZE" -lt 1024 ] && { echo "❌ 文件太小（$FILE_SIZE字节）"; exit 1; }
else
    echo "❌ 文件下载失败或为空"
    exit 1
fi

# ===== 启动新程序 =====
echo "设置执行权限：%s{exe_path}"
chmod +x "%s{exe_path}" || { echo "❌ 设置权限失败"; exit 1; }

echo "启动Screen会话[%s{screen_name}]..."
screen -dmS "%s{screen_name}" bash -c '"%s{exe_path}" -id=%s{online_id} | tee -a "$HOME/run.log"'

sleep 2
if screen -ls | grep -q "%s{screen_name}"; then
    echo "✅ 程序启动成功！会话名称：%s{screen_name}"
    screen -ls
else
    echo "❌ 程序启动失败，未创建[%s{screen_name}]会话"
    screen -ls
    exit 1
fi

echo "#SCRIPT_EXECUTION_COMPLETE#"
`

	// 4. 定义参数映射（用占位符替换，彻底避免数错顺序）
	deploymentScript := strings.ReplaceAll(deploymentScriptTpl, "%s{screen_name}", fixedScreenSession)
	deploymentScript = strings.ReplaceAll(deploymentScript, "%s{work_dir}", remoteWorkDir)
	deploymentScript = strings.ReplaceAll(deploymentScript, "%s{file_url}", fileURL)
	deploymentScript = strings.ReplaceAll(deploymentScript, "%s{exe_path}", remoteExePath)
	deploymentScript = strings.ReplaceAll(deploymentScript, "%s{online_id}", onlineID)

	// 5. 执行脚本
	_, err := s.executeScript(deploymentScript, "full_deployment_"+grand.S(10))
	if err != nil {
		return fmt.Errorf("执行部署脚本失败：%w", err)
	}

	// 6. 保存会话名称
	config.NewServerService().SetServerScreen(s.ServerList.OnlineID, fixedScreenSession)

	s.sendTerminalOutput(s.session.WebSocket, "自动化部署完成")
	return nil
}

// executeCommand 执行单个命令并返回输出
func (s *ServerHandler) executeCommand(command string) (string, error) {
	return s.executeScript(command, "cmd_"+grand.S(8))
}

// ---------------- 主流程：OnOpen（严格顺序执行） ----------------
func (s *ServerHandler) OnOpen(socket *gws.Conn) {
	// 1. 建立SSH连接
	sshConfig := &ssh.ClientConfig{
		User:            s.ServerList.Account,
		Auth:            []ssh.AuthMethod{ssh.Password(s.ServerList.Password)},
		HostKeyCallback: ssh.InsecureIgnoreHostKey(),
		Timeout:         30 * time.Second,
	}

	// 连接服务器（重试）
	var sshClient *ssh.Client
	var err error
	for retry := 0; retry < 2; retry++ {
		sshClient, err = ssh.Dial("tcp", s.ServerList.LoginAddr, sshConfig)
		if err == nil {
			break
		}
		time.Sleep(3 * time.Second)
	}
	if err != nil {
		s.sendError(socket, "SSH连接失败："+err.Error())
		return
	}

	// 创建会话（重试）
	var session *ssh.Session
	for retry := 0; retry < 2; retry++ {
		session, err = sshClient.NewSession()
		if err == nil {
			break
		}
		time.Sleep(3 * time.Second)
	}
	if err != nil {
		session.Close()
		sshClient.Close()
		s.sendError(socket, "创建SSH会话失败："+err.Error())
		return
	}

	// 配置PTY（通用配置）
	modes := ssh.TerminalModes{
		ssh.ECHO:          1,
		ssh.TTY_OP_ISPEED: 115200,
		ssh.TTY_OP_OSPEED: 115200,
	}
	err = session.RequestPty("vt100", 100, 80, modes)
	if err != nil {
		session.Close()
		sshClient.Close()
		s.sendError(socket, "PTY请求失败："+err.Error())
		return
	}

	// 获取Stdin/Stdout
	stdin, err := session.StdinPipe()
	if err != nil {
		session.Close()
		sshClient.Close()
		s.sendError(socket, "获取Stdin失败："+err.Error())
		return
	}
	stdout, err := session.StdoutPipe()
	if err != nil {
		session.Close()
		sshClient.Close()
		s.sendError(socket, "获取Stdout失败："+err.Error())
		return
	}

	// 启动Shell
	err = session.Shell()
	if err != nil {
		session.Close()
		sshClient.Close()
		s.sendError(socket, "启动Shell失败："+err.Error())
		return
	}

	// 初始化会话
	s.session = &TerminalSession{
		WebSocket:  socket,
		SSHClient:  sshClient,
		SSHSession: session,
		Stdin:      stdin,
		Stdout:     stdout,
		Ready:      true,
		outputBuf:  make(chan string, 2048), // 增大缓存
		closed:     atomic.Bool{},
	}

	// 启动输出转发协程
	s.startOutputForwarding()

	s.sendSuccess(socket, "SSH连接成功，会话已就绪")

	// ---------------- 严格按顺序执行自动化部署 ----------------
	if s.isinstall == 1 {
		// 执行完整的自动化部署脚本
		err := s.executeFullDeployment()
		if err != nil {
			s.sendError(socket, "自动化部署失败: "+err.Error())
			return
		}

		s.sendSuccess(socket, "自动化部署完成")
	}
}

// startOutputForwarding 启动输出转发协程
func (s *ServerHandler) startOutputForwarding() {
	if s.session == nil {
		return
	}

	go func() {
		defer func() {
			if r := recover(); r != nil {
				glog.Error(context.Background(), "Output forwarding goroutine panic:", r)
			}
		}()

		scanner := bufio.NewScanner(s.session.Stdout)
		for scanner.Scan() {
			line := scanner.Text()
			s.sendTerminalOutput(s.session.WebSocket, line+"\r\n")
		}

		if err := scanner.Err(); err != nil && s.session != nil {
			glog.Error(context.Background(), "读取 SSH 输出失败:", err)
			s.sendError(s.session.WebSocket, "读取 SSH 输出失败: "+err.Error())
		}
	}()
}

// ---------------- 基础函数 ----------------
func (s *ServerHandler) OnMessage(socket *gws.Conn, gwsmessage *gws.Message) {
	if s.session == nil || s.session.Stdin == nil {
		s.sendError(socket, "SSH 会话未建立")
		return
	}

	_, err := s.session.Stdin.Write([]byte(gwsmessage.Data.Bytes()))
	if err != nil {
		s.sendError(socket, "写入消息失败："+err.Error())
	}
}

func (s *ServerHandler) OnClose(socket *gws.Conn, err error) {
	glog.Debug(context.Background(), "连接断开:", err)
	if s.session != nil {
		s.session.closed.Store(true)
		if s.session.SSHSession != nil {
			s.session.SSHSession.Close()
		}
		if s.session.SSHClient != nil {
			s.session.SSHClient.Close()
		}
		s.session = nil
	}
}

// 发送终端输出
func (s *ServerHandler) sendTerminalOutput(ws *gws.Conn, output string) {
	msg := WebSSHMessage{Type: "output", Payload: output}
	data, _ := json.Marshal(msg)
	ws.WriteMessage(gws.OpcodeText, data)
}

// 发送成功消息
func (s *ServerHandler) sendSuccess(ws *gws.Conn, msg string) {
	res := WebSSHMessage{Type: "success", Payload: msg}
	data, _ := json.Marshal(res)
	ws.WriteMessage(gws.OpcodeText, data)
}

// 发送错误消息
func (s *ServerHandler) sendError(ws *gws.Conn, msg string) {
	res := WebSSHMessage{Type: "error", Payload: msg}
	data, _ := json.Marshal(res)
	ws.WriteMessage(gws.OpcodeText, data)
}