using System;
using System.IO;
using System.Reflection;
using Harmony;
using UnityEngine;

namespace Doorstop
{
    /// <summary>
    /// Einstieg ohne MSCLoader: Unity Doorstop (winhttp.dll im Spielordner) ruft beim Spielstart diese Methode auf - der
    /// MSCO Launcher startet das Spiel mit "--doorstop-target-assembly ...\MSCO\MSCO.dll", MSCLoader wird dann gar nicht
    /// geladen. Hier läuft noch nichts von Unity: nur vorbereiten, gestartet wird im Hauptmenü (siehe MSCO.Bootstrap).
    /// </summary>
    public static class Entrypoint
    {
        public static void Start()
        {
            MSCO.Bootstrap.Start();
        }
    }
}

namespace MSCO
{
    /// <summary>
    /// Startet MSCO eigenständig: Abhängigkeiten (Harmony, Newtonsoft.Json) aus dem MSCO-Ordner laden, warten bis das
    /// Spiel seinen Code geladen hat, dann beim ersten PlayMakerArrayListProxy.Awake (Hauptmenü, Hauptthread) den
    /// MultiplayerManager anlegen. Protokoll: &lt;Spiel&gt;\MSCO\MSCO_Loader.txt.
    /// </summary>
    public static class Bootstrap
    {
        static string folder;
        static bool patched, started;
        static StreamWriter log;

        public static void Start()
        {
            try
            {
                folder = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
                log = new StreamWriter(Path.Combine(folder, "MSCO_Loader.txt"), false) { AutoFlush = true };
                Log("MSCO " + MSCO.ModVersion + " loader started (standalone, without MSCLoader)");
                Log("Command line: " + string.Join(" ", Environment.GetCommandLineArgs()));
                AppDomain.CurrentDomain.AssemblyResolve += Resolve;
                AppDomain.CurrentDomain.AssemblyLoad += (_, e) => OnAssemblyLoaded(e.LoadedAssembly);
                foreach (Assembly a in AppDomain.CurrentDomain.GetAssemblies()) OnAssemblyLoaded(a);
            }
            catch (Exception e)
            {
                Log("Loader failed: " + e);
            }
        }

        public static void Log(string line)
        {
            try { if (log != null) log.WriteLine(DateTime.Now.ToString("HH:mm:ss") + "  " + line); } catch { }
        }

        /// <summary>Unsere Abhängigkeiten liegen neben MSCO.dll (das Spiel sucht nur in Managed).</summary>
        static Assembly Resolve(object sender, ResolveEventArgs args)
        {
            try
            {
                string name = new AssemblyName(args.Name).Name;
                string file = Path.Combine(folder, name + ".dll");
                if (File.Exists(file)) return Assembly.LoadFrom(file);
            }
            catch (Exception e) { Log("Resolve " + args.Name + " failed: " + e.Message); }
            return null;
        }

        static void OnAssemblyLoaded(Assembly assembly)
        {
            if (patched) return;
            string name;
            try { name = assembly.GetName().Name; } catch { return; }
            if (name != "Assembly-CSharp") return;
            patched = true;
            try { Patch(assembly); }
            catch (Exception e) { Log("Could not hook into the game: " + e); }
        }

        /// <summary>Haken in PlayMakerArrayListProxy.Awake (läuft im Hauptmenü früh auf dem Hauptthread).</summary>
        static void Patch(Assembly game)
        {
            Type proxy = game.GetType("PlayMakerArrayListProxy");
            MethodInfo awake = proxy != null ? proxy.GetMethod("Awake", BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic) : null;
            if (awake == null)
            {
                Log("PlayMakerArrayListProxy.Awake not found - MSCO cannot start");
                return;
            }
            HarmonyInstance.Create("mbm.msco.bootstrap").Patch(awake,
                new HarmonyMethod(typeof(Bootstrap).GetMethod("BeforeAwake", BindingFlags.Static | BindingFlags.NonPublic)), null);
            Log("Hooked into the game, waiting for the main menu");
        }

        static void BeforeAwake()
        {
            if (started) return;
            started = true;
            try
            {
                var go = new GameObject("MSCO_Host");
                UnityEngine.Object.DontDestroyOnLoad(go);
                go.AddComponent<MscoHost>();
                Log("MSCO started");
            }
            catch (Exception e) { Log("Start failed: " + e); }
        }
    }

    /// <summary>Lebt über alle Szenen: legt im Hauptmenü den MultiplayerManager an (früher MSCLoaders OnMenuLoad).</summary>
    public class MscoHost : MonoBehaviour
    {
        void Start()
        {
            MscoLog.Info("Welcome to MSCO by mbm.wtf");
            // Den Nachrichten-Bildschirm des Spiels ("Latest news ... press any key") überspringen - direkt ins Hauptmenü
            string scene = Application.loadedLevelName;
            Bootstrap.Log("First scene: " + scene);
            if (scene != "MainMenu" && scene != "GAME")
            {
                Bootstrap.Log("Skipping the intro/news screen");
                Application.LoadLevel("MainMenu");
                return;
            }
            MultiplayerManager.Ensure();
        }

        void OnLevelWasLoaded(int level)
        {
            Bootstrap.Log("Level loaded: " + Application.loadedLevelName);
            MultiplayerManager.Ensure();
        }

        void OnApplicationQuit()
        {
            // Wer beendet das Spiel? (Diagnose)
            Bootstrap.Log("Game is quitting (scene " + Application.loadedLevelName + "): " + System.Environment.StackTrace);
        }
    }
}