module Server

[<EntryPoint>]
let main argv =
    let port = 8080
    //Use svarende til C#, kalder dispose ved GB
    use hl = new System.Net.HttpListener ()
    hl.Prefixes.Add <| sprintf "http://+:%d/" port //%d inserts port intro string
    //Starting server
    hl.Start ()

    //Server loop for handling requests
    let rec loop ()  =
        let ctx         = hl.GetContext()
        let request     = ctx.Request
        let response    = ctx.Response
        let meth        = request.HttpMethod
        let path        = request.RawUrl
        let rip         = request.RemoteEndPoint.Address
        let rport       = request.RemoteEndPoint.Port

        //Waiting for incomming HTTP Requests
        let body =
            use is = new System.IO.StreamReader(request.InputStream, request.ContentEncoding)
            is.ReadToEnd()

        //Eg "Create /resorce/C from ::1 57916 [data]"
        printfn "%s %s from %s %d [%s]" meth path (rip.ToString()) rport body

        //Function for sending a reply, calls loop recusive
        //Mangler at have en globalstate/store er sendes rundt
        let reply answer status reason =
            printfn "--> %d %s %s" status reason answer //Prints response to shell
            //Sets responsevalues "imperative"
            response.StatusCode         <- status
            response.StatusDescription  <- reason
            //Transforms answer string -> byte []
            let buffer = System.Text.Encoding.UTF8.GetBytes(answer)
            response.ContentLength64    <-  int64 buffer.Length
            response.OutputStream.Write(buffer, 0, buffer.Length)
            response.OutputStream.Close();
            loop ()

        match meth with
        | "GET"      -> reply "Handling Get" 200 "OK"
        | "PUT"      -> reply "Handling Put" 200 "OK"
        | "DELETE"   -> reply "Handling Delete" 200 "OK"
        | "CREATE"   -> reply "Handling Create" 200 "OK"

    //Starting loop
    loop ()