// for FSharp-Interactive:
#r "../packages/SSH.NET/lib/net40/Renci.SshNet.dll"

open Renci.SshNet
open System.IO

/// FSharp Async wrapper for SSH.NET SFTP
type SftpClient with
    member x.ListDirectoryAsync path =
        Async.FromBeginEnd((fun(iar,state) ->
            x.BeginListDirectory(path, iar, state)), x.EndListDirectory)

    member x.DownloadFileAsync path output =
        Async.FromBeginEnd((fun(iar,state) ->
            x.BeginDownloadFile(path, output, iar, state)), x.EndDownloadFile)

    member x.UploadFileAsync input path =
        Async.FromBeginEnd((fun(iar,state) ->
            x.BeginUploadFile(input, path, iar, state)), x.EndUploadFile)
        |> Async.Catch

    member x.SynchronizeDirectoriesAsync sourcePath destinationPath searchPattern =
        Async.FromBeginEnd((fun(iar,state) ->
            x.BeginSynchronizeDirectories(
                sourcePath, destinationPath, searchPattern, iar, state)),
            x.EndSynchronizeDirectories)
        |> Async.Catch

let downloadDir = @"c:\temp"
let uploadfile = @"c:\temp\file.txt"

let sftpExample host port username (password:string) =
    async {
        let workDir = "."
        use client = new SftpClient(host, port, username, password)
        client.Connect()
        printfn "Connected to %s" host

        // Change directory:
        client.ChangeDirectory workDir

        // List files in directory:
        let! listDirectory = client.ListDirectoryAsync workDir
        listDirectory |> Seq.iter(fun file ->
            if file.IsDirectory then printfn "/%s" file.Name
            else printfn "%s" file.Name)

        // Download a file:
        let fileName = "manual_en.pdf"
        use fileStream = File.OpenWrite(Path.Combine(downloadDir, fileName))
        printfn "Downloading %s..." fileName
        do! client.DownloadFileAsync ("./download/"+fileName) fileStream
        printfn "Downloaded %s (%i bytes)" fileName fileStream.Length

        // Upload a file:
        client.ChangeDirectory "upload"
        use fileStream = new FileStream(uploadfile, FileMode.Open)
        printfn "Uploading %s (%i bytes)" uploadfile fileStream.Length
        client.BufferSize <- 4096u // bypass Payload error large files
        let! r = client.UploadFileAsync fileStream (Path.GetFileName uploadfile)
        match r with
        | Choice1Of2 _ -> printfn "Uploaded %s" uploadfile
        | Choice2Of2 err -> printf "Error uploading %s: %O" uploadfile err

    } |> Async.StartAsTask

let test =
   sftpExample "demo.wftpserver.com" 2222 "demo-user" "demo-user"