using HarmonyLib;
using KFCommonUtilityLib.Scripts.StaticManagers;
using System.Collections.Generic;
using System.Linq;
using System.Reflection.Emit;

namespace KFCommonUtilityLib.Harmony
{
    [HarmonyPatch]
    public static class InvariableRPMPatches
    {
        //added as a transpiler so that it's applied before all post processing
        [HarmonyPatch(typeof(ItemActionRanged), nameof(ItemActionRanged.OnHoldingUpdate))]
        [HarmonyTranspiler]
        private static IEnumerable<CodeInstruction> Transpiler_OnHoldingUpdate_ItemActionRanged(IEnumerable<CodeInstruction> instructions)
        {
            var codes = instructions.ToList();

            var mtd_getvalue = AccessTools.Method(typeof(EffectManager), nameof(EffectManager.GetValue));

            for (int i = 0; i < codes.Count; i++)
            {
                if (codes[i].Calls(mtd_getvalue))
                {
                    int start = -1;
                    for (int j = i; j >= 0; j--)
                    {
                        if (codes[j].opcode == OpCodes.Stloc_0)
                        {
                            start = j + 2;
                            break;
                        }
                    }
                    if (start >= 0)
                    {
                        codes.InsertRange(i + 2, new[]
                        {
                            new CodeInstruction(OpCodes.Ldarg_0),
                            new CodeInstruction(OpCodes.Ldloc_0),
                            CodeInstruction.Call(typeof(InvariableRPMPatches), nameof(InvariableRPMPatches.CalcFixedRPM))
                        });
                        codes.RemoveRange(start, i - start + 2);
                        Log.Out("Invariable RPM Patch applied!");
                    }
                    break;
                }
            }

            return codes;
        }

        private static float CalcFixedRPM(ItemActionRanged rangedAction, ItemActionRanged.ItemActionDataRanged rangedData)
        {
            float res;
            if (rangedAction is IModuleContainerFor<ActionModuleInvariableRPM> actionModule)
            {
                float rpm = 60f / rangedData.OriginalDelay;
                float perc = 1f;
                var tags = rangedData.invData.item.ItemTags;
                MultiActionManager.ModifyItemTags(rangedData.invData.itemValue, rangedData, ref tags);
                rangedData.invData.item.Effects.ModifyValue(rangedData.invData.holdingEntity, PassiveEffects.RoundsPerMinute, ref rpm, ref perc, rangedData.invData.itemValue.Quality, tags);
                res = rpm * perc;
                //Log.Out($"fixed RPM {res}");
            }
            else
            {
                res = EffectManager.GetValue(PassiveEffects.RoundsPerMinute, rangedData.invData.itemValue, 60f / rangedData.OriginalDelay, rangedData.invData.holdingEntity);
            }
            res = 60f / res;
            return res;
        }
    }
}