musiccontrol.fs

#load "load-project-debug.fsx"

// REF: https://github.com/MarshallOfSound/Google-Play-Music-Desktop-Player-UNOFFICIAL-/blob/master/docs/PlaybackAPI_WebSocket.md

open System
open System.Net.WebSockets
open System.Threading
open System.Threading.Tasks
open System.Text
open System.Text.RegularExpressions
open Newtonsoft.Json

let ws = new ClientWebSocket()

printf "Connecting..."
async { return! ws.ConnectAsync(new Uri("ws://localhost:5672"), CancellationToken.None) |> Async.AwaitTask }
    |> Async.RunSynchronously
printfn "Done: %A" ws.State

// Receive information
let buffer = Array.zeroCreate 1024
let rec listen (ws: ClientWebSocket) =
    let keepGoing =
        async {
            let seg  = ArraySegment buffer
            let! msg = ws.ReceiveAsync(seg, CancellationToken.None) |> Async.AwaitTask

            return
                match msg.MessageType with
                | WebSocketMessageType.Close ->
                    printfn "> closed"
                    false
                | WebSocketMessageType.Text ->
                    let str = Encoding.UTF8.GetString(buffer, 0, msg.Count)
                    printfn "%s" str
                    true
                | _ ->
                    printfn "binary %A bytes" msg.Count
                    true
        } |> Async.RunSynchronously

    if keepGoing then listen ws

// listen ws

// Send Commands
let send (ws: ClientWebSocket) (value: string) =
    let buffer = Encoding.UTF8.GetBytes(value)
    let seg    = ArraySegment buffer

    async { return! ws.SendAsync(seg, WebSocketMessageType.Text, true, CancellationToken.None) |> Async.AwaitTask }
        |> Async.RunSynchronously

type CommandArg =
    // Volume =
    | Volume_SetVolume of int
    | Volume_IncreaseVolume of int
    | Volume_DecreaseVolume of int

    // Playback =
    | Playback_SetPlayback of int
    | Playback_PlayPause
    | Playback_Forward
    | Playback_Rewind
    | Playback_ToggleShuffle
    | Playback_ToggleRepeat
    | Playback_ToggleVisualization

    // Rating =
    | Rating_ToggleThumbsUp
    | Rating_ToggleThumbDown
    | Rating_SetRating of int
    | Rating_ResetRating

let command (x: CommandArg) =
    let command channel command arg =
        sprintf """{
          "namespace": "%s",
          "method": "%s",
          "arguments": [%s]
        }
        """ channel command arg

    let lowerFirst (s: string) =
        string (Char.ToLower(s.[0])) + s.Substring(1)

    match x with
    | _ ->
        printfn "%A" x
        let reg = Regex @"^(?<namespace>\w+?)_(?<method>\w+?)( (?<arg>.+))?$"
        let m   = reg.Match( sprintf "%A" x )
        match m.Success with
        | true ->
            let ns  = lowerFirst (m.Groups.["namespace"].Value)
            let cmd = lowerFirst (m.Groups.["method"].Value)
            let arg = m.Groups.["arg"].Value
            command ns cmd arg |> send ws
        | false ->
            failwith <| sprintf "Not Handled: %A" x

command Playback_PlayPause