namespace RodhernF

open UnityEngine
open KSP

[<KSPAddon(KSPAddon.Startup.EveryScene, true)>]
type RodhernF () = 
    inherit MonoBehaviour ()
    
    /// Write message to the KSP.log file.
    let log s =
        do Debug.Log ("[RodhernF] " + s)
   
    /// Write message on screen and to log file.
    let msg s =
        do log s
        do ScreenMessages.PostScreenMessage(s, 5.f) |> ignore
    
    /// A handler called when a change of scene is requested.
    let onSceneSwitchRequest =
        let handler (actionFromTo: GameEvents.FromToAction<GameScenes,GameScenes>) =
            do sprintf "Going from '%A' to '%A'."
                       (actionFromTo.``from``) (actionFromTo.``to``)
               |> msg
        new EventData<_>.OnEvent(handler)
    
    /// A handler called when a vessel is selected in the launch dialog.
    let onVesselSelect =
        let handler (template: ShipTemplate) =
            do sprintf "Selected '%s'."
                       (template.shipName)
               |> msg
        new EventData<_>.OnEvent(handler)
    
    /// This is the method that KSP/Unity will invoke.
    member public rodhernf.Start () =
        do log "rodhernf.Start begin"
        GameEvents.onGameSceneSwitchRequested.Add onSceneSwitchRequest
        GameEvents.onGUILaunchScreenVesselSelected.Add onVesselSelect
        do log "rodhernf.Start end"