Kodakamp2.fs

open System.IO
open System.Security.Cryptography

type Config =
    { maxFileSize: int64
      startPath: string }

type FileResult =
    { hash: string
      fullPath: string }

let filterTooSmallFiles maxFileSize files =
    files
    |> Seq.filter(fun f -> FileInfo(f).Length > maxFileSize)

let getChecksum file =
    use stream = new BufferedStream(File.OpenRead(file), 1200000)
    stream |> MD5.Create().ComputeHash

let rec getAllFiles dirPath =
    seq { yield! Directory.GetFiles(dirPath)
          for subDir in Directory.EnumerateDirectories(dirPath) do
                    yield! getAllFiles subDir }

let go config = 
    config.startPath 
    |> DirectoryInfo
    |> fun di -> printfn "Finding files from your path: %s ..." di.FullName
                 config.startPath 
                 |> getAllFiles
                 |> filterTooSmallFiles config.maxFileSize
                 |> Seq.map(fun f -> { hash = f |> getChecksum |> System.Text.Encoding.ASCII.GetString
                                       fullPath = f  })
                 |> Seq.groupBy(fun f -> f.hash)
                 |> Seq.filter(fun (k, seq) -> seq |> Seq.length > 1)
                 |> Seq.iter(fun (k, seq) -> printfn "\nThe following files are the same:"
                                             seq |> Seq.iter(fun f -> printfn "File: %s" f.fullPath))

[<EntryPoint>]
let main args = 
    printfn "You have selected these parameters for this adventure: \n max size (bytes):  %s \n and start path: %s" args.[0] args.[1]
    printfn "\nPress the windows and apple key to continue"
    System.Console.ReadKey() |> ignore
    
    { maxFileSize = int64 args.[0]
      startPath = args.[1] }
    |> go
    
    printfn "\nPress the button on your keyboard labeled \"any key\" to close"
    System.Console.ReadKey() |> ignore
    0