using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using BSO.Net;

namespace BSO
{
    /// <summary>
    /// Anzeige oben links: eigene Position (LocalPlayer) und Online-Status mit allen Mitspielern (Multiplayer).
    /// F9 blendet ein/aus, F10 schreibt alle Entities in eine Datei.
    ///
    /// Update rechnet (wenn die Engine-Uhr weiterlaeuft), Draw gibt den fertigen Text bei jedem Durchlauf aus - die
    /// Engine zeigt Vision::Message-Text nur fuer einen Durchlauf, sonst flackert die Anzeige.
    /// </summary>
    public static class PositionHud
    {
        const int X = 10, Y = 10, Line = 18;

        static bool visible = true, rateLogged;
        static int frame;
        static string status = "";
        static byte[][] lines = Array.Empty<byte[]>();

        static readonly Stopwatch rateClock = Stopwatch.StartNew();
        static int draws;

        public static void Update()
        {
            frame++;
            if (Input.Pressed(Input.F9)) visible = !visible;
            if (!LocalPlayer.InScene) { lines = Array.Empty<byte[]>(); return; } // Menue / Laden
            if (Input.Pressed(Input.F10))
            {
                Entities.Dump(LocalPlayer.Camera);
                status = "Entities gespeichert: BSO\\entities.txt";
            }

            // Text nur alle paar Durchlaeufe neu bauen - Draw gibt ihn dazwischen unveraendert aus
            if (frame % 5 != 0 && lines.Length > 0) return;
            PlayerState me = LocalPlayer.State;
            var text = new List<string>
            {
                $"BSO {Bootstrap.ModVersion}   [F8] Online   [F9] Anzeige   [F10] Entities   [F11] Vollbild/Fenster",
                me.Mode switch
                {
                    PlayerMode.InBus => $"Du:  im Bus  {LocalPlayer.Bus.Pos}   {LocalPlayer.Speed * 0.036f:0} km/h",
                    PlayerMode.OnFoot => $"Du:  zu Fuss  {LocalPlayer.Character.Pos}" + (LocalPlayer.Bus.Valid ? $"   Bus {Meters(LocalPlayer.Bus.Pos - LocalPlayer.Character.Pos)} entfernt" : ""),
                    _ => "Du:  -"
                },
                "",
            };
            AddOnline(text, me);
            if (status.Length > 0) text.Add(status);
            lines = text.ConvertAll(Vision.ToAscii).ToArray();
        }

        static void AddOnline(List<string> text, PlayerState me)
        {
            switch (Multiplayer.Status)
            {
                case Multiplayer.NetStatus.Offline when Multiplayer.AccountProblem != null:
                    text.Add(Multiplayer.AccountProblem);
                    return;
                case Multiplayer.NetStatus.Offline:
                    text.Add($"Offline - [F8] verbinden mit {Multiplayer.ServerAddress} als {Multiplayer.PlayerName}");
                    if (Multiplayer.LastError.Length > 0) text.Add("  " + Multiplayer.LastError);
                    return;
                case Multiplayer.NetStatus.Connecting:
                    text.Add($"Verbinde mit {Multiplayer.ServerAddress} ...");
                    return;
            }
            if (!Multiplayer.Welcomed)
            {
                text.Add($"Verbinde mit {Multiplayer.ServerAddress} ... warte auf Server");
                return;
            }

            string ping = Multiplayer.PingMs >= 0 ? $"{Multiplayer.PingMs} ms" : "...";
            text.Add($"Online: \"{Multiplayer.ServerName}\" ({ping}) - {Multiplayer.Players.Count + 1} Spieler   [F8] trennen");
            foreach (Multiplayer.Remote p in Multiplayer.Players.Values.OrderBy(p => p.HasState ? p.State.DistanceTo(me) : float.MaxValue))
            {
                if (!p.HasState || p.State.Mode == PlayerMode.Menu) { text.Add($"  {p.Name,-16}  im Menue"); continue; }
                string mode = p.State.Mode == PlayerMode.InBus ? "Bus     " : "zu Fuss ";
                string dist = me.Mode == PlayerMode.Menu ? "" : $"{p.State.DistanceTo(me) / 100,6:0} m";
                text.Add($"  {p.Name,-16}  {mode} {dist}   {p.State.Speed * 0.036f,3:0} km/h");
            }
        }

        static string Meters(Vec3 d) => $"{d.Length / 100:0} m";

        public static void Draw()
        {
            CountDraws();
            if (!visible) return;
            byte[][] current = lines;
            for (int i = 0; i < current.Length; i++) Vision.Print(X, Y + i * Line, current[i]);
        }

        static void CountDraws()
        {
            draws++;
            if (rateLogged || rateClock.ElapsedMilliseconds < 5000) return;
            if (!LocalPlayer.InScene) { draws = 0; rateClock.Restart(); return; } // erst im Spiel messen
            rateLogged = true;
            Bootstrap.Log($"Anzeige: {draws / 5} Durchlaeufe pro Sekunde");
        }
    }
}