package main

import (
	"fmt"
	"path"
	"path/filepath"
	"strconv"
	"strings"
	"time"

	"u-desk/internal/filesystem"
	"u-desk/internal/sftp"
)

// ========== SFTP 接口 ==========

func (a *App) ensureSftpService() *sftp.Service {
	a.mu.Lock()
	defer a.mu.Unlock()
	if a.sftpService == nil {
		a.sftpService = sftp.NewService()
	}
	return a.sftpService
}

// SftpConnect 建立 SFTP 连接，返回连接标识符 connID
func (a *App) SftpConnect(req SftpConnectRequest) (string, error) {
	config := &sftp.Config{
		Host:          req.Host,
		Port:          req.Port,
		Username:      req.Username,
		Password:      req.Password,
		KeyPath:       req.KeyPath,
		KeyPassphrase: req.KeyPassphrase,
	}
	if config.Port == 0 {
		config.Port = 22
	}
	if config.Timeout == 0 {
		config.Timeout = 15 * time.Second
	}

	svc := a.ensureSftpService()
	_, err := svc.GetManager().Connect(config)
	if err != nil {
		return "", sftp.ToUserMessage(err)
	}

	connID := sftp.ConnID(config.Host, config.Port)
	return connID, nil
}

// SftpDisconnect 断开 SFTP 连接
func (a *App) SftpDisconnect(connID string) error {
	parts := strings.SplitN(connID, ":", 2)
	if len(parts) < 2 {
		return fmt.Errorf("无效的连接标识符")
	}
	host := parts[0]
	port, err := strconv.Atoi(parts[1])
	if err != nil {
		return fmt.Errorf("无效的端口号")
	}

	sftp.GetManager().Disconnect(host, port)
	return nil
}

// SftpListDir SFTP 列出目录
func (a *App) SftpListDir(connID string, dirPath string) ([]map[string]interface{}, error) {
	return a.ensureSftpService().ListDir(connID, dirPath)
}

// SftpReadFile SFTP 读取文件内容
func (a *App) SftpReadFile(connID string, filePath string) (string, error) {
	return a.ensureSftpService().ReadFile(connID, filePath)
}

// SftpWriteFile SFTP 写入文件
func (a *App) SftpWriteFile(req SftpWriteFileRequest) error {
	return a.ensureSftpService().WriteFile(req.SessionID, req.Path, req.Content)
}

// SftpWriteBase64File SFTP 写入 base64 编码的二进制文件（粘贴图片等）
func (a *App) SftpWriteBase64File(sessionID, filePath, base64Content string) error {
	return a.ensureSftpService().WriteBase64File(sessionID, filePath, base64Content)
}

// SftpGetFileInfo SFTP 获取文件信息
func (a *App) SftpGetFileInfo(connID string, filePath string) (map[string]interface{}, error) {
	return a.ensureSftpService().GetFileInfo(connID, filePath)
}

// SftpCreateDir SFTP 创建目录
func (a *App) SftpCreateDir(connID string, dirPath string) (*filesystem.FileOperationResult, error) {
	return a.ensureSftpService().CreateDir(connID, dirPath)
}

// SftpCreateFile SFTP 创建文件
func (a *App) SftpCreateFile(connID string, filePath string) (*filesystem.FileOperationResult, error) {
	return a.ensureSftpService().CreateFile(connID, filePath)
}

// SftpDeletePath SFTP 删除文件或目录
func (a *App) SftpDeletePath(connID string, filePath string) (*filesystem.FileOperationResult, error) {
	return a.ensureSftpService().DeletePath(connID, filePath)
}

// SftpRenamePath SFTP 重命名文件或目录
func (a *App) SftpRenamePath(req SftpRenamePathRequest) (*filesystem.FileOperationResult, error) {
	return a.ensureSftpService().RenamePath(req.SessionID, req.OldPath, req.NewPath)
}

// SftpDownloadToTemp 下载远程文件到本地临时目录（用于预览）
func (a *App) SftpDownloadToTemp(connID string, remotePath string) (string, error) {
	return a.ensureSftpService().DownloadToTemp(connID, remotePath)
}

// SftpDownloadSiteForPreview 下载 HTML 及其网站资源到本地临时目录
func (a *App) SftpDownloadSiteForPreview(connID string, remotePath string) (string, error) {
	return a.ensureSftpService().DownloadSiteForPreview(connID, remotePath)
}

// SftpDownloadToTempCached 带缓存的 SFTP 下载（命中缓存直接返回本地路径）
func (a *App) SftpDownloadToTempCached(connID string, remotePath string, fileSize int64, modTime string) (string, error) {
	return a.ensureSftpService().DownloadToTempCached(connID, remotePath, fileSize, modTime)
}

// SftpDownloadToFile 下载远程文件/目录到用户指定目录（流式无上限，重名自动副本），返回本地落地路径
func (a *App) SftpDownloadToFile(connID string, remotePath string, localDstDir string) (string, error) {
	emitter := newTransferEmitter(a, "download", path.Base(remotePath))
	localPath, err := a.ensureSftpService().DownloadToFile(connID, remotePath, localDstDir, emitter.progress)
	emitter.finish(err)
	return localPath, err
}

// SftpUploadFromFile 上传本地文件/目录到远程目录（流式，目录递归，重名自动副本）
func (a *App) SftpUploadFromFile(connID string, localPath string, remoteDir string) error {
	emitter := newTransferEmitter(a, "upload", filepath.Base(localPath))
	err := a.ensureSftpService().UploadFromFile(connID, localPath, remoteDir, emitter.progress)
	emitter.finish(err)
	return err
}

// SftpGetCommonPaths 获取 SFTP 远程主机常用路径
func (a *App) SftpGetCommonPaths(connID string) (map[string]string, error) {
	return a.ensureSftpService().GetCommonPaths(connID)
}

// SftpGetSystemInfo 获取 SFTP 远程主机系统信息（CPU/内存/磁盘）
func (a *App) SftpGetSystemInfo(connID string) (map[string]interface{}, error) {
	return a.ensureSftpService().GetSystemInfo(connID)
}