using HarmonyLib;
using RimWorld;
using rjw;
using RJWSexperience.Ideology.HistoryEvents;
using RJWSexperience.Ideology.Precepts;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using System.Reflection.Emit;
using Verse;

namespace RJWSexperience.Ideology.Patches
{
	[HarmonyPatch(typeof(MarriageCeremonyUtility), nameof(MarriageCeremonyUtility.Married))]
	public static class Rimworld_Patch_Marriage
	{
		public static void Postfix(Pawn firstPawn, Pawn secondPawn)
		{
			RsiHistoryEventDefOf.RSI_NonIncestuosMarriage.RecordEventWithPartner(firstPawn, secondPawn);
			RsiHistoryEventDefOf.RSI_NonIncestuosMarriage.RecordEventWithPartner(secondPawn, firstPawn);
		}
	}

	[HarmonyPatch(typeof(RitualOutcomeEffectWorker_FromQuality), "GiveMemoryToPawn")]
	public static class Rimworld_Patch_RitualOutcome_DontGiveMemoryToAnimals
	{
		public static bool Prefix(Pawn pawn)
		{
			return !pawn.IsAnimal();
		}
	}

	[HarmonyPatch(typeof(IdeoFoundation), nameof(IdeoFoundation.CanAdd))]
	public static class Rimworld_Patch_IdeoFoundation
	{
		public static void Postfix(PreceptDef precept, ref IdeoFoundation __instance, ref AcceptanceReport __result)
		{
			DefExtension_MultipleMemesRequired extension = precept.GetModExtension<DefExtension_MultipleMemesRequired>();

			if (extension == null)
				return;

			if (extension.requiredAllMemes.NullOrEmpty())
				return;

			for (int i = 0; i < extension.requiredAllMemes.Count; i++)
			{
				if (!__instance.ideo.memes.Contains(extension.requiredAllMemes[i]))
				{
					List<string> report = new List<string>();
					foreach (MemeDef meme in extension.requiredAllMemes) report.Add(meme.LabelCap);

					__result = new AcceptanceReport("RequiresMeme".Translate() + ": " + report.ToCommaList());
					return;
				}
			}
		}
	}

	[HarmonyPatch(typeof(RelationsUtility), "Incestuous")]
	public static class Rimworld_Patch_IncestuousManualRomance
	{
		/// <summary>
		/// Override incestuous check in the manual romance
		/// </summary>
		/// <param name="one">Pawn to try do romance</param>
		/// <param name="two">Target for romance</param>
		/// <param name="__result">Result of the original method</param>
		/// <returns>Run original method implementation</returns>
		public static bool Prefix(Pawn one, Pawn two, ref bool __result)
		{
			__result = RsiIncestuous(one, two);
			return false;
		}

		/// <summary>
		/// Check if Ideology allows romance attempt
		/// </summary>
		/// <param name="one">Pawn to try do romance</param>
		/// <param name="two">Target for romance</param>
		/// <returns>Forbid romance option</returns>
		public static bool RsiIncestuous(Pawn one, Pawn two)
		{
			PreceptDef incestuousPrecept = one.Ideo?.PreceptsListForReading.Select(precept => precept.def).FirstOrFallback(def => def.issue == VariousDefOf.Incestuos);
			var allowManualRomanceOnlyFor = incestuousPrecept?.GetModExtension<DefExtension_Incest>()?.allowManualRomanceOnlyFor;
			BloodRelationDegree relationDegree = RelationHelpers.GetBloodRelationDegree(one, two);

			if (allowManualRomanceOnlyFor == null)
			{
				return relationDegree < BloodRelationDegree.NotRelated;
			}

			return !allowManualRomanceOnlyFor.Contains(relationDegree);
		}
	}

	[HarmonyPatch(typeof(Pawn_RelationsTracker), nameof(Pawn_RelationsTracker.SecondaryRomanceChanceFactor))]
	public static class Rimworld_Patch_SecondaryRomanceChanceFactor
	{
		/// <summary>
		/// <para>
		/// Replace
		/// float num = 1f;
		/// foreach (PawnRelationDef pawnRelationDef in this.pawn.GetRelations(otherPawn))
		/// {
		/// 	num *= pawnRelationDef.romanceChanceFactor;
		/// }
		/// </para>
		/// <para>with</para>
		/// <para>
		/// float num = 1f;
		/// num = RomanceChanceFactorHelpers.GetRomanceChanceFactor(this.pawn, otherPawn)
		/// </para>
		/// </summary>
		/// <param name="instructions">Original method body</param>
		/// <returns>Modified method body</returns>
		public static IEnumerable<CodeInstruction> Transpiler(IEnumerable<CodeInstruction> instructions)
		{
			MethodInfo getRelationsInfo = AccessTools.Method(
				typeof(PawnRelationUtility),
				nameof(PawnRelationUtility.GetRelations),
				new[] { typeof(Pawn), typeof(Pawn) });
			MethodInfo helperInfo = AccessTools.Method(
				typeof(RomanceChanceFactorHelpers),
				nameof(RomanceChanceFactorHelpers.GetRomanceChanceFactor),
				new[] { typeof(Pawn), typeof(Pawn) });
			bool skipping = false;
			bool yieldNext = false;
			bool finished = false;

			// Original IL looks something like this:
			// Load this.pawn
			// Load otherPawn
			// Call GetRelations
			// Start loop
			// ...
			// Mul num and romanceChanceFactor
			// Store result
			// ...
			// Endfinaly

			// Idea is to substitute GetRelations call with a method with the same signature,
			// store results in the same place original loop does and remove everything else until Endfinaly

			foreach (CodeInstruction instruction in instructions)
			{
				if (finished)
				{
					yield return instruction;
					continue;
				}

				if (skipping)
				{
					if (yieldNext)
					{
						yield return instruction;
						yieldNext = false;
					}
					else if (instruction.opcode == OpCodes.Mul)
					{
						yieldNext = true;
					}
					else if (instruction.opcode == OpCodes.Endfinally)
					{
						finished = true;
					}

					continue;
				}

				if (instruction.Calls(getRelationsInfo))
				{
					yield return new CodeInstruction(OpCodes.Call, helperInfo);
					skipping = true;
					continue;
				}

				yield return instruction;
			}
		}
	}
}