using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Reflection;
using System.Text;
using HarmonyLib;

internal static class KeepsakeToolPatch
{
    private static readonly Type Palette =
        typeof(RecRoom.AGUI.ToolUIs.MakerPenPaletteMainScreen);

    private static readonly Type Registry = typeof(PMJEHEPKBJL);

    private static readonly Type ToolTypeEnum = typeof(AOCJJLANBMH);

    private static readonly Type ToolConfig = typeof(RuntimeSpawnableToolConfig);


    private static readonly Dictionary<string, int> RepeatedLines = new Dictionary<string, int>();

    private static string Mode
        => (Environment.GetEnvironmentVariable("RADICADE_KEEPSAKE_TOOL")
            ?? (RadicadeEacBypassPlugin.KeepsakeToolEnabled?.Value == true ? "on" : "skip")).Trim();

    private static bool Requested => Mode.ToLowerInvariant() switch
    {
        "on" or "true" or "1" or "yes" or "enable" or "enabled" => true,
        "off" or "false" or "0" => true,
        _ => false,
    };

    internal static bool Forcing => Mode.ToLowerInvariant() switch
    {
        "on" or "true" or "1" or "yes" or "enable" or "enabled" => true,
        _ => false,
    };

    internal static void Apply(Harmony harmony)
    {
        if (!Requested)
        {
            return;
        }

        if (Palette == null || Registry == null || ToolTypeEnum == null)
        {
            RadicadeEacBypassPlugin.LogSource.LogWarning(
                "[Keepsake] palette/registry/tool-type type not found (" +
                $"palette={Palette?.FullName ?? "null"}, registry={Registry?.FullName ?? "null"}, " +
                $"toolType={ToolTypeEnum?.FullName ?? "null"}) - keepsake patch skipped");
            return;
        }


        Patch(harmony, Registry, "JBAINDGLMBO", new[] { ToolTypeEnum }, null, nameof(ConfigPostfix));

        PatchByName(harmony, Registry, "LPBDCDIMBEN", nameof(PredicatePostfix));


        PatchByNameOnFamily(harmony, Palette, "LKGMIHJOIID", nameof(PredicatePostfix));
        PatchByNameOnFamily(harmony, Palette, "OLKPEGJNJGG", nameof(ConfigFilterPostfix));
        PatchByNameOnFamily(harmony, Palette, "IBHJBFJMBFB", nameof(ConfigFilterPostfix));

        Patch(harmony, Palette, "OnUsedPaletteItem", null, nameof(UsedPalettePrefix), null);

        Audit(harmony);
    }

    private static void Audit(Harmony harmony)
    {
        var service = AccessTools.TypeByName("AMAOGLDGNLL");
        foreach (var name in new[]
                 {
                     "MJDEEABFHPJ", "NCAKOLMAAEA", "CAFCLGFGKAO", "KHPJGNADGEE", "NGJMABOMHHB",
                     "FCOMKMPDEIO", "AEHHFFIKLG"
                 })
            PatchByName(harmony, service, name, nameof(CallPostfix), 2);

        if (!string.Equals(Environment.GetEnvironmentVariable("RADICADE_KEEPSAKE_AUDIT"), "1",
                StringComparison.Ordinal)) return;

        Log("[Keepsake] RADICADE_KEEPSAKE_AUDIT=1: instrumenting the room/progression models too");
        foreach (var typeName in new[] { "RRUI.Data.RoomModel", "RRUI.Data.RoomListModel", "RRUI.Data.ProgressionEventsModel" })
        {
            var model = AccessTools.TypeByName(typeName);
            foreach (var name in new[]
                     {
                         "IsKeepsakeRoom", "GetCachedAreAllKeepsakesCollected",
                         "GetTotalKeepsakeCountPerCategoryForRoom", "GetUncollectedKeepsakeCountPerCategoryForRoom",
                         "GetTotalKeepsakeCountForRoom", "GetUncollectedKeepsakeCountForRoom",
                         "IsKeepsakeRoomListUpsellItemOwned", "AHACLFABDEO", "CJPFGOBHGBB"
                     })
                PatchByName(harmony, model, name, nameof(ModelPostfix), 4);
        }

    }

    internal static object KeepsakeMember()
    {
        try
        {
            return ToolTypeEnum == null ? null : Enum.Parse(ToolTypeEnum, "KEEPSAKE");
        }
        catch (Exception e)
        {
            RadicadeEacBypassPlugin.LogSource.LogWarning("[Keepsake] KEEPSAKE enum member missing: " + e.Message);
            return null;
        }
    }

    internal static bool IsKeepsake(object toolType)
        => toolType != null && KeepsakeMember()?.Equals(toolType) == true;

    internal static void Log(string message)
        => RadicadeEacBypassPlugin.LogSource.LogInfo(message);

    private static void LogOnce(string message, int limit = 3)
    {
        var seen = RepeatedLines.TryGetValue(message, out var count) ? count + 1 : 1;
        RepeatedLines[message] = seen;
        if (seen <= limit) Log(message);
        else if (seen == limit + 1) Log($"[Keepsake] (suppressing further copies of: {message})");
    }


    private static void ConfigPostfix(object[] __args, RuntimeSpawnableToolConfig __result)
    {
        var toolType = __args.Length > 0 ? __args[0] : null;
        var keepsake = IsKeepsake(toolType);
        if (!keepsake && !IsRestricted(__result)) return;


        if (!keepsake || !Forcing) return;

        var allowed = Field(__result, "spawnableToolTypesAllowedInRooms2");
        if (Contains(allowed, KeepsakeMember())) return;
        AddToCollection(allowed, KeepsakeMember());
    }

    private static void PredicatePostfix(MethodBase __originalMethod, object[] __args, ref bool __result)
    {
        var toolType = FirstToolType(__args);
        var keepsake = IsKeepsake(toolType);

        if (keepsake && Forcing && !__result)
        {
            __result = true;
        }
    }

    private static void CallPostfix(MethodBase __originalMethod, object[] __args, object __result)
    {
    }

    private static void ModelPostfix(MethodBase __originalMethod, object[] __args, object __result)
    {
    }

    private static string DescribeResult(object result)
    {
        if (result == null) return "(null)";
        var type = result.GetType();
        try
        {
            if (type == typeof(bool) || type == typeof(int) || type == typeof(long))
                return result.ToString();

            var status = AccessTools.Property(type, "IsCompleted")?.GetValue(result) as bool?;
            if (status == true)
            {
                var value = AccessTools.Property(type, "Result")?.GetValue(result);
                return $"{type.Name}(completed) = {value}";
            }

            if (status == false) return $"{type.Name}(pending)";
        }
        catch
        {
        }

        return type.Name;
    }

    private static void ConfigFilterPostfix(MethodBase __originalMethod, object[] __args, ref bool __result)
    {
        var config = __args.Length > 0 ? __args[0] : null;
        var name = Field(config, "UniqueName")?.ToString() ?? "(unnamed tool)";
        var keepsake = string.Equals(name, "KEEPSAKE", StringComparison.OrdinalIgnoreCase);
        if (!keepsake) return;

        if (!Forcing || __result) return;

        __result = true;
    }

    private static void UsedPalettePrefix(object[] __args)
    {
    }


    private static object FirstToolType(object[] args)
    {
        if (args == null) return null;
        foreach (var arg in args)
        {
            if (arg == null) continue;
            if (ToolTypeEnum.IsInstanceOfType(arg) || arg.GetType() == ToolTypeEnum) return arg;
        }

        return null;
    }

    private static bool IsRestricted(object config)
        => Field(config, "AvailableInMakerPen") is bool makerPen && !makerPen;

    private static string Frames(int take = 10)
    {
        try
        {
            var frames = new StackTrace(true).GetFrames();
            var sb = new StringBuilder();
            var taken = 0;
            foreach (var frame in frames)
            {
                var method = frame.GetMethod();
                var owner = method?.DeclaringType?.Name ?? "?";
                if (owner.Contains("KeepsakeToolPatch") || owner.Contains("Harmony")) continue;
                sb.Append(owner).Append('.').Append(method?.Name ?? "?").Append(" <- ");
                if (++taken >= take) break;
            }
            return sb.Length == 0 ? "(no frames)" : sb.ToString().TrimEnd(' ', '<', '-');
        }
        catch (Exception e)
        {
            return "(stack failed: " + e.GetType().Name + ")";
        }
    }

    private static string DescribeList(object collection)
    {
        if (collection == null) return "(null)";
        var type = collection.GetType();

        var count = 0;
        var keepsake = false;
        var names = new StringBuilder();
        try
        {
            var countValue = AccessTools.Property(type, "Count")?.GetValue(collection);
            count = countValue is int n ? n : 0;
            if (count == 0) return "0 item(s) []";

            var indexer = type.GetProperty("Item");
            for (var i = 0; i < count && i < 12; i++)
            {
                var item = indexer?.GetValue(collection, new object[] { i });
                if (IsKeepsake(item)) keepsake = true;
                names.Append(item).Append(',');
            }
        }
        catch (Exception e)
        {
            return $"(list read failed: {e.GetType().Name}: {e.Message})";
        }

        return $"{count} item(s) [{names.ToString().TrimEnd(',')}]" + (keepsake ? " KEEPSAKE present" : "");
    }

    private static bool Contains(object collection, object item)
    {
        if (collection == null || item == null) return false;
        try
        {
            var contains = AccessTools.Method(collection.GetType(), "Contains");
            return contains?.Invoke(collection, new[] { item }) is true;
        }
        catch
        {
            return false;
        }
    }

    private static bool AddToCollection(object collection, object item)
    {
        if (collection == null || item == null) return false;
        try
        {
            var type = collection.GetType();
            MethodInfo add = null;
            foreach (var candidate in type.GetMethods(BindingFlags.Public | BindingFlags.Instance))
            {
                if (candidate.Name != "Add" || candidate.GetParameters().Length != 1) continue;
                add = candidate;
                break;
            }

            if (add == null) return false;
            add.Invoke(collection, new[] { item });
            return true;
        }
        catch (Exception e)
        {
            RadicadeEacBypassPlugin.LogSource.LogWarning(
                $"[Keepsake] could not add to {collection.GetType().Name}: {e.GetType().Name}: {e.Message}");
            return false;
        }
    }

    private static string Describe(object config)
    {
        if (config == null) return "(null config)";

        var sb = new StringBuilder(config.GetType().Name).Append('{');
        foreach (var name in new[]
                 {
                     "UniqueName", "AvailableInMakerPen", "AvailableToDevsOnly", "IsBetaItem",
                     "AvailableInSpawner", "CanSaveIntoInventions", "LimitInventionSaveForJuniors"
                 })
        {
            var value = Field(config, name);
            if (value != null) sb.Append(name).Append('=').Append(value).Append(' ');
        }

        var allowed = Field(config, "spawnableToolTypesAllowedInRooms2");
        if (allowed != null)
            sb.Append("allowedInRooms=").Append(DescribeList(allowed)).Append(' ');

        return sb.Append('}').ToString();
    }

    private static object Field(object instance, string name)
    {
        if (instance == null) return null;
        try
        {
            var type = instance.GetType();
            var property = AccessTools.Property(type, name);
            if (property != null) return property.GetValue(instance);
            return AccessTools.Field(type, name)?.GetValue(instance);
        }
        catch
        {
            return null;
        }
    }


    private static void PatchByNameOnFamily(Harmony harmony, Type root, string method, string postfix)
    {
        var patched = 0;
        foreach (var type in Family(root))
        {
            foreach (var found in type.GetMethods(BindingFlags.Public | BindingFlags.NonPublic
                                                  | BindingFlags.Static | BindingFlags.Instance))
            {
                if (found.Name != method) continue;
                if (Bind(harmony, found, null, postfix)) patched++;
            }
        }

        if (patched == 0)
            RadicadeEacBypassPlugin.LogSource.LogWarning(
                $"[Keepsake] no method named {method} on {root.Name} or its nested types - not instrumented");
    }

    private static void PatchByName(Harmony harmony, Type target, string method, string postfix,
        int maxArguments = 1)
    {
        if (target == null)
        {
            RadicadeEacBypassPlugin.LogSource.LogWarning(
                $"[Keepsake] type for {method} not found - not instrumented");
            return;
        }

        var patched = 0;
        foreach (var found in target.GetMethods(BindingFlags.Public | BindingFlags.NonPublic
                                                | BindingFlags.Static | BindingFlags.Instance))
        {
            if (found.Name != method) continue;
            var parameters = found.GetParameters();
            if (parameters.Length > maxArguments) continue;
            if (parameters.Any(p => p.ParameterType.IsByRef || p.IsOut || p.ParameterType.IsPointer)) continue;
            if (maxArguments == 1 && (parameters.Length != 1 ||
                (!ToolTypeEnum.IsAssignableFrom(parameters[0].ParameterType)
                 && parameters[0].ParameterType != ToolTypeEnum))) continue;
            if (Bind(harmony, found, null, postfix)) patched++;
        }

    }

    private static IEnumerable<Type> Family(Type root)
    {
        yield return root;
        Type[] nested;
        try
        {
            nested = root.GetNestedTypes(BindingFlags.Public | BindingFlags.NonPublic);
        }
        catch
        {
            yield break;
        }

        foreach (var type in nested)
            foreach (var deeper in Family(type))
                yield return deeper;
    }

    private static void Patch(Harmony harmony, Type target, string method, Type[] args,
        string prefix, string postfix)
    {
        if (target == null)
        {
            RadicadeEacBypassPlugin.LogSource.LogWarning($"[Keepsake] type for {method} not found - not instrumented");
            return;
        }

        try
        {
            var found = args == null
                ? AccessTools.Method(target, method)
                : AccessTools.Method(target, method, args);
            if (found == null)
            {
                RadicadeEacBypassPlugin.LogSource.LogWarning(
                    $"[Keepsake] {target.Name}.{method} not found - not instrumented");
                return;
            }

            Bind(harmony, found, prefix, postfix);
        }
        catch (Exception e)
        {
            RadicadeEacBypassPlugin.LogSource.LogWarning(
                $"[Keepsake] FAILED to instrument {target.Name}.{method}: {e.GetType().Name}: {e.Message}");
        }
    }

    private static bool Bind(Harmony harmony, MethodBase found, string prefix, string postfix)
    {
        try
        {
            var self = typeof(KeepsakeToolPatch);
            const BindingFlags flags = BindingFlags.Static | BindingFlags.NonPublic;
            harmony.Patch(found,
                prefix: prefix == null ? null : new HarmonyMethod(self.GetMethod(prefix, flags)),
                postfix: postfix == null ? null : new HarmonyMethod(self.GetMethod(postfix, flags)));
            return true;
        }
        catch (Exception e)
        {
            RadicadeEacBypassPlugin.LogSource.LogWarning(
                $"[Keepsake] FAILED to instrument {found.DeclaringType?.Name}.{found.Name}: " +
                $"{e.GetType().Name}: {e.Message}");
            return false;
        }
    }
}