using Kryz.CharacterStats.Examples;
using System.Collections.Generic;
using System.Linq;
using UnityEngine;

[System.Serializable]
public class WeightedEquipmentType
{
    public EquippableItemTypeDefinition equipmentType;
    public float weight = 1f;
    public DifficultyLevels lowestPossibleDifficulty = DifficultyLevels.E;
    public DifficultyLevels highestPossibleDifficulty = DifficultyLevels.SS;

    public int LowestDifficultyDrop => (int)lowestPossibleDifficulty;
    public int HighestDifficultyDrop => (int)highestPossibleDifficulty;
}

public class EquipmentDropTable : MonoBehaviour
{
    [Header("Drop Settings")]
    [SerializeField] private int dropChance = 50; // Percentage chance to drop equipment
    [SerializeField] private EquippableItemGenerator.ItemTier minTier = EquippableItemGenerator.ItemTier.Common;
    [SerializeField] private EquippableItemGenerator.ItemTier maxTier = EquippableItemGenerator.ItemTier.Rare;

    [Header("Equipment Types")]
    [SerializeField] private List<WeightedEquipmentType> possibleEquipment = new List<WeightedEquipmentType>();

    [Header("Coin Drop")]
    [SerializeField] private GameObject coinPrefab;
    [SerializeField] private int coinAmount = 10;
    [SerializeField] private GameEvent_Int onCoinDrop;

    [Header("Prefabs")]
    [SerializeField] private GameObject equipmentDropPrefab; // Should have EquippableItemDrop component

    [Header("Level Scaling")]
    [SerializeField] private bool usePlayerLevel = true;
    [SerializeField] private int fixedLevel = 1;

    public void DropLoot()
    {
        Vector3 dropPosition = transform.position;
        dropPosition.y = 0f;

        // Always drop coins
        DropCoins(dropPosition);

        // Roll for equipment drop
        if (ShouldDropEquipment())
        {
            DropRandomEquipment(dropPosition);
        }
    }

    private void DropCoins(Vector3 position)
    {
        if (coinPrefab == null) return;

        GameObject coinDrop = Instantiate(coinPrefab, position, transform.rotation);
        CoinDrop coinDropComponent = coinDrop.GetComponent<CoinDrop>();

        if (coinDropComponent != null)
        {
            // Apply difficulty scaling if available
            int finalAmount = coinAmount;
            if (GameDifficultyController.Instance != null)
            {
                finalAmount = Mathf.RoundToInt(coinAmount * (1 + GameConstants.GameBalancing.IncreasedCoinDropBasedOnDifficultyMultiplier * GameDifficultyController.Instance.GetCurrentDifficultyLevel()));
            }

            coinDropComponent.Init(finalAmount);
            onCoinDrop?.Raise(finalAmount);
        }
    }

    private bool ShouldDropEquipment()
    {
        if (possibleEquipment.Count == 0) return false;

        // Apply difficulty scaling to drop chance if available
        float finalDropChance = dropChance;
        if (GameDifficultyController.Instance != null)
        {
            finalDropChance *= (1 + GameConstants.GameBalancing.IncreasedItemDropBasedOnDifficultyMultiplier * GameDifficultyController.Instance.GetCurrentDifficultyLevel());
        }

        return Random.Range(0f, 100f) < finalDropChance;
    }

    private void DropRandomEquipment(Vector3 position)
    {
        // Select random equipment type based on weights
        EquippableItemTypeDefinition selectedType = GetRandomWeightedEquipmentType();
        if (selectedType == null) return;

        // Generate random tier within range
        EquippableItemGenerator.ItemTier randomTier = GetRandomTier();

        // Determine item level
        int itemLevel = usePlayerLevel ? GetPlayerLevel() : fixedLevel;

        // Generate the item using your existing generator
        EquippableItemInstance generatedItem = EquippableItemGenerator.Instance.GenerateFromEquipmentType(
            selectedType,
            randomTier,
            itemLevel
        );

        // Create the interactable drop
        SpawnEquipmentDrop(generatedItem, position);

        Debug.Log($"Dropped {randomTier} {selectedType.GetDisplayName()} (Level {itemLevel})");
    }

    private EquippableItemTypeDefinition GetRandomWeightedEquipmentType()
    {
        int currentDifficulty = GameDifficultyController.Instance?.GetCurrentDifficultyLevel() ?? 0;

        // Filter equipment types for current difficulty and null checks
        var validEquipment = possibleEquipment.Where(e =>
            e.equipmentType != null &&
            e.LowestDifficultyDrop <= currentDifficulty &&
            e.HighestDifficultyDrop >= currentDifficulty
        ).ToList();

        if (validEquipment.Count == 0)
        {
            Debug.LogWarning($"No equipment available for difficulty level {currentDifficulty}");
            return null;
        }

        // Calculate total weight for valid equipment
        float totalWeight = validEquipment.Sum(e => e.weight);
        if (totalWeight <= 0)
        {
            // If no weights, pick randomly from valid equipment
            return validEquipment[Random.Range(0, validEquipment.Count)].equipmentType;
        }

        // Weighted random selection
        float randomValue = Random.Range(0f, totalWeight);
        float currentWeight = 0f;

        foreach (var equipment in validEquipment)
        {
            currentWeight += equipment.weight;
            if (randomValue <= currentWeight)
            {
                return equipment.equipmentType;
            }
        }

        return validEquipment[0].equipmentType; // Fallback
    }

    private EquippableItemGenerator.ItemTier GetRandomTier()
    {
        int minTierValue = (int)minTier;
        int maxTierValue = (int)maxTier;
        int randomTierValue = Random.Range(minTierValue, maxTierValue + 1);

        return (EquippableItemGenerator.ItemTier)randomTierValue;
    }

    private void SpawnEquipmentDrop(EquippableItemInstance item, Vector3 position)
    {
        if (equipmentDropPrefab == null)
        {
            Debug.LogError("Equipment drop prefab is not assigned!");
            return;
        }

        GameObject dropObject = Instantiate(equipmentDropPrefab, position, transform.rotation);
        EquippableItemDrop dropComponent = dropObject.GetComponent<EquippableItemDrop>();

        if (dropComponent != null)
        {
            dropComponent.itemDrop = item;
        }
        else
        {
            Debug.LogError("Equipment drop prefab doesn't have EquippableItemDrop component!");
            Destroy(dropObject);
        }
    }

    private int GetPlayerLevel()
    {
        // Replace this with your actual player level system
        // For example: return PlayerController.Instance.Level;
        return 1; // Placeholder
    }

    #region Editor Testing
    [ContextMenu("Test Drop")]
    private void TestDrop()
    {
        if (Application.isPlaying)
        {
            DropLoot();
        }
        else
        {
            Debug.Log("Test drop only works in play mode");
        }
    }

    [ContextMenu("Validate Setup")]
    private void ValidateSetup()
    {
        int issues = 0;
        int currentDifficulty = GameDifficultyController.Instance?.GetCurrentDifficultyLevel() ?? 0;

        if (possibleEquipment.Count == 0)
        {
            Debug.LogWarning("No equipment types configured");
            issues++;
        }

        int validForCurrentDifficulty = 0;
        foreach (var equipment in possibleEquipment)
        {
            if (equipment.equipmentType == null)
            {
                Debug.LogWarning("Found null equipment type reference");
                issues++;
            }
            else if (equipment.LowestDifficultyDrop <= currentDifficulty &&
                     equipment.HighestDifficultyDrop >= currentDifficulty)
            {
                validForCurrentDifficulty++;
            }
        }

        if (validForCurrentDifficulty == 0 && possibleEquipment.Count > 0)
        {
            Debug.LogWarning($"No equipment types are valid for current difficulty level {currentDifficulty}");
            issues++;
        }

        if (equipmentDropPrefab == null)
        {
            Debug.LogWarning("Equipment drop prefab not assigned");
            issues++;
        }
        else if (equipmentDropPrefab.GetComponent<EquippableItemDrop>() == null)
        {
            Debug.LogWarning("Equipment drop prefab missing EquippableItemDrop component");
            issues++;
        }

        if (coinPrefab == null)
        {
            Debug.LogWarning("Coin prefab not assigned");
            issues++;
        }

        if (issues == 0)
        {
            Debug.Log($"Equipment drop table setup is valid! {validForCurrentDifficulty} equipment types available for current difficulty.");
        }
        else
        {
            Debug.LogWarning($"Found {issues} setup issues");
        }
    }
    #endregion
}