using System;
using System.Collections.Generic;
using HarmonyLib;
using UnityEngine;

namespace NecromancerTome
{
	/// <summary>
	/// "Пространственный браслет" (Spatial Bracelet) - dictated 2026-08-30, implemented same
	/// day. See items.xml (braceletSpatialVault) for the item - both Action0 and Action1 use
	/// Class="Eat" purely as a click-catcher (same trick as every other Harmony-driven item this
	/// mod already has), distinguished here by ItemActionData.indexInEntityOfAction (0/1), the
	/// same field SummonPatch.cs already uses to tell a summon book's summon-click from its
	/// recall-click.
	///
	/// POWER ATTACK (index 1) - personal storage, size scaling with Necromancy skill level:
	///   - XUiC_BagStorageWindowGroup.Open(xui, entity, bag, lootContainer, title, ...) is the
	///     REAL API EntityDrone.openStorageWindow() itself calls to show the drone's own cargo
	///     window (decompiled EntityDrone directly to find this, not guessed) - reused directly
	///     rather than reinventing a storage UI. LootContainer.GetLootContainer("roboticDrone")
	///     is the same display/behavior template the drone's own window uses too - "как у дрона"
	///     taken literally, not just as a vague size comparison.
	///   - Slot count = Mathf.RoundToInt(necromancyLevel / 10f), per the user's own exact formula
	///     ("1*скилл_некроманта/10 округлённый до целого") - read live from
	///     player.Progression.GetProgressionValue("craftingNecroNecromancy").Level (decompiled
	///     EntityAlive/Progression/ProgressionValue directly to confirm this exact call shape,
	///     not guessed) - the SAME skill the Knife's own damage already scales with (capped at
	///     level 5000, one level per zombie kill - see buffs.xml/progression.xml), so this grows
	///     at the same pace as every other kill-count-tied payoff in this mod. Below level 10
	///     this rounds to 0 - deliberately left as-is, not special-cased away, matching the
	///     Knife's own "0 at 0 kills is a feature, not a bug" precedent - a tooltip explains it
	///     instead of silently opening a useless empty window.
	///   - PERSISTENCE - solved 2026-09-13, see SpatialVaultPersistence.cs. It was NOT solved
	///     when this item shipped, and that shortfall is exactly what became the mod's first
	///     Nexus bug report (youkia96581, 11 Sep 2026: "Items stored in the space bracelet will
	///     disappear after leaving the game and going online again"). PlayerVaults below is still
	///     the in-memory, entityId-keyed Dictionary it always was, but it is now only the session
	///     cache: the durable copy is written into the player's own PlayerDataFile, alongside the
	///     backpack, by four postfixes on FromPlayer/ToPlayer/Write/Read. Read that file's comment
	///     for why there ("почему не сделать принцип как у ящика?" - because a chest's items live
	///     in a chunk, and the bracelet's closest equivalent home is its owner's save data).
	///
	/// REGULAR ATTACK (index 0) - knock back + slow whatever zombie the crosshair is aimed at:
	///   - Same raycast mechanism HarmonySrc/ThiefLoopPatch.cs already established for
	///     braceletThiefLoop (GetLookRay + Physics.Raycast + RootTransformRefEntity.
	///     FindEntityUpwards) - reused verbatim, just resolving to EntityZombie instead of
	///     EntityLootContainer.
	///   - Slow: zombie.Buffs.AddBuff("buffInjurySlow") - the exact same vanilla debuff already
	///     reused elsewhere in this mod (the Dog's own bite, necroMeleeHandZombieDog).
	///   - Knockback: DELIBERATELY a straight Entity.SetPosition "shove" (same API
	///     PetFollowPatch.cs already uses to reposition pets), NOT a physics/ragdoll impulse.
	///     Found real candidates for "proper" knockback while researching this
	///     (EntityAlive.DoRagdoll(in DamageResponse), DamageResponse.ImpulseScale/HitDirection),
	///     but fully reverse-engineering how a real DamageResponse gets built and fed into that
	///     during normal combat - all its other fields (Source, Strength, Stun, ArmorSlot, etc.)
	///     - would have taken real additional decompilation with no guarantee of getting all the
	///     coordinate/enum conventions right on the first try. A direct position shove is cruder
	///     (no animation, the zombie just appears further away) but uses an API this exact file's
	///     own family already relies on successfully - chosen for certainty over polish. Revisit
	///     with DoRagdoll if the teleport-shove feels too crude in testing.
	/// </summary>
	[HarmonyPatch(typeof(ItemActionEat), "ExecuteAction")]
	public static class Patch_ItemActionEat_ExecuteAction_SpatialVault
	{
		public const string ItemName = "braceletSpatialVault";
		public const string NecromancySkillName = "craftingNecroNecromancy";
		public const float MaxRange = 50f;
		public const float ShoveDistance = 6f;

		/// <summary>Session cache only - the durable copy lives on disk, see
		/// SpatialVaultPersistence.cs. Cleared on WorldShuttingDown so a different save loaded
		/// afterwards cannot inherit this world's vault through a recycled entityId.</summary>
		public static readonly Dictionary<int, Bag> PlayerVaults = new Dictionary<int, Bag>();

		public static bool Prefix(ItemActionData _actionData, bool _bReleased)
		{
			if (!_bReleased)
			{
				return true;
			}
			string itemName = _actionData?.invData?.itemValue?.ItemClass?.Name;
			if (itemName != ItemName)
			{
				return true;
			}
			if (!(_actionData.invData.holdingEntity is EntityPlayerLocal player))
			{
				return true;
			}

			if (_actionData.indexInEntityOfAction == 1)
			{
				OpenVault(player);
			}
			// else: regular attack (index 0) deliberately does nothing, per direct user request
			// 2026-08-30 ("пусть тогда обычная атака у пространственного браслета не делает
			// ничего") after the knockback+slow version didn't visibly do anything in testing -
			// rather than debug ShoveZombieAtCrosshair blind (kept below, unused, in case this
			// gets revisited), just absorb the click silently.

			// Skip ItemActionEat's own logic entirely - the click has been fully handled here.
			return false;
		}

		public static void OpenVault(EntityPlayerLocal player)
		{
			ProgressionValue progressionValue = player.Progression?.GetProgressionValue(NecromancySkillName);
			int level = progressionValue != null ? progressionValue.Level : 0;
			int slotCount = Mathf.RoundToInt(level / 10f);
			if (slotCount <= 0)
			{
				GameManager.ShowTooltip(player, "braceletSpatialVaultTooWeak");
				return;
			}

			if (!PlayerVaults.TryGetValue(player.entityId, out Bag bag))
			{
				// Normally a restored vault is already here - the ToPlayer postfix puts it in
				// when the game applies the save file to the spawning player. LastLoadedVault is
				// the safety net for when that chain does not complete: opening the bracelet must
				// never be what silently starts an empty vault over a saved one. Only then is a
				// genuinely new bag created.
				bag = SpatialVaultPersistence.LastLoadedVault ?? new Bag(slotCount);
				if (bag == SpatialVaultPersistence.LastLoadedVault)
				{
					Debug.Log("[NecromancerTome] SpatialVaultPatch: session cache was empty, adopted the last loaded vault (" +
					          bag.SlotCount + " slots, " + bag.GetUsedSlotCount() + " used)");
				}
				PlayerVaults[player.entityId] = bag;
			}
			else if (bag.SlotCount < slotCount)
			{
				// Grow, never shrink - the skill level only ever goes up, so this only ever
				// copies existing stacks into a bigger array, same shape
				// EntityLootContainer.SetContent itself uses when it needs to resize a bag.
				ItemStack[] oldSlots = bag.GetSlots();
				ItemStack[] newSlots = ItemStack.CreateArray(slotCount);
				Array.Copy(oldSlots, newSlots, oldSlots.Length);
				bag.SetSlots(newSlots);
			}

			Debug.Log("[NecromancerTome] SpatialVaultPatch: owner=" + player.entityId + " opened vault, " + slotCount + " slots (Necromancy level " + level + ")");
			LocalPlayerUI playerUI = LocalPlayerUI.GetUIForPlayer(player);
			// The trailing callbacks are vanilla's own optional parameters (_onModified, _onClose).
			// _onModified is not needed: the vault lives in PlayerVaults, and PlayerDataFile's
			// FromPlayer postfix reads it fresh every time the game saves the player, so there is
			// nothing to flush per item move. _onClose asks for a player-data save right away, so
			// closing the window is a commit point rather than waiting for the next autosave -
			// SaveLocalPlayerData is the game's own routine call and no-ops when saving is not
			// active (which is the correct behaviour on a client, where the server owns the file).
			XUiC_BagStorageWindowGroup.Open(
				playerUI.xui,
				player,
				bag,
				LootContainer.GetLootContainer("roboticDrone"),
				Localization.Get("braceletSpatialVaultWindowTitle"),
				null,
				() => GameManager.Instance.SaveLocalPlayerData());
		}

		public static void ShoveZombieAtCrosshair(EntityPlayerLocal player)
		{
			Ray ray = player.GetLookRay();
			if (!Physics.Raycast(ray, out RaycastHit hit, MaxRange))
			{
				GameManager.ShowTooltip(player, "braceletSpatialVaultNoTarget");
				return;
			}
			Transform entityTransform = RootTransformRefEntity.FindEntityUpwards(hit.collider.transform);
			Entity entity = entityTransform != null ? entityTransform.GetComponent<Entity>() : null;
			if (!(entity is EntityZombie zombie) || zombie.IsDead())
			{
				GameManager.ShowTooltip(player, "braceletSpatialVaultNoTarget");
				return;
			}

			zombie.Buffs?.AddBuff("buffInjurySlow");

			Vector3 shoveDir = zombie.position - player.position;
			shoveDir.y = 0f;
			shoveDir = shoveDir.sqrMagnitude > 0.01f ? shoveDir.normalized : player.transform.forward;
			Vector3 destination = zombie.position + shoveDir * ShoveDistance + Vector3.up * 1f;
			zombie.SetPosition(destination, true);

			player.PlayOneShot("swoosh");
			Debug.Log("[NecromancerTome] SpatialVaultPatch: owner=" + player.entityId + " shoved zombie " + zombie.entityId);
		}
	}
}