namespace Minecraft.Server.FourKit.Inventory.Meta;

using Minecraft.Server.FourKit.Enchantments;

/// <summary>
/// Represents the metadata of an <see cref="ItemStack"/>, including display name and lore.
/// </summary>
public class ItemMeta
{
    private string? _displayName;
    private Dictionary<EnchantmentType, int>? _enchants;
    private List<string>? _lore;

    /// <summary>
    /// Checks for existence of a display name.
    /// </summary>
    /// <returns>true if this has a display name.</returns>
    public bool hasDisplayName() => _displayName != null;

    /// <summary>
    /// Gets the display name that is set.
    /// Plugins should check that hasDisplayName() returns true before calling this method.
    /// </summary>
    /// <returns>The display name that is set.</returns>
    public string getDisplayName() => _displayName ?? string.Empty;

    /// <summary>
    /// Sets the display name.
    /// </summary>
    /// <param name="name">The name to set.</param>
    public void setDisplayName(string? name) => _displayName = name;

    /// <summary>
    /// Checks for existence of lore.
    /// </summary>
    /// <returns>true if this has lore.</returns>
    public bool hasLore() => _lore != null && _lore.Count > 0;

    /// <summary>
    /// Gets the lore that is set.
    /// Plugins should check if hasLore() returns true before calling this method.
    /// </summary>
    /// <returns>A list of lore that is set.</returns>
    public List<string> getLore() => _lore != null ? new List<string>(_lore) : new List<string>();

    /// <summary>
    /// Sets the lore for this item. Removes lore when given null.
    /// </summary>
    /// <param name="lore">The lore that will be set.</param>
    public void setLore(List<string>? lore)
    {
        _lore = lore != null ? new List<string>(lore) : null;
    }

    /// <summary>
    /// Adds the specified enchantment to this item meta.
    /// </summary>
    /// <param name="enchantment">Enchantment to add</param>
    /// <param name="level">Level for the enchantment</param>
    /// <param name="ignoreLevelRestriction">Indicates the enchantment should be applied, ignoring the level limit</param>
    /// <returns>true if the item meta changed as a result of this call, false otherwise</returns>
    public bool addEnchant(EnchantmentType enchantment, int level, bool ignoreLevelRestriction)
    {
        if (_enchants == null)
            _enchants = new Dictionary<EnchantmentType, int>();

        if (!ignoreLevelRestriction)
        {
            Enchantment enchant = Enchantment.getByType(enchantment);

            if (enchant.getMaxLevel() < level) return false;
        }

        try
        {
            _enchants.Add(enchantment, level);
            return true;
        } catch { }

        return false;
    }

    /// <summary>
    /// Removes the specified enchantment from this item meta.
    /// </summary>
    /// <param name="enchantment">Enchantment to remove</param>
    /// <returns>true if the item meta changed as a result of this call, false otherwise</returns>
    public bool removeEnchant(EnchantmentType enchantment)
    {
        if (!hasEnchant(enchantment)) return false;

        return _enchants.Remove(enchantment);
    }

    /// <summary>
    /// Returns a copy of the enchantments in this ItemMeta. Returns an empty map if none.
    /// </summary>
    /// <returns>An immutable copy of the enchantments</returns>
    public Dictionary<EnchantmentType, int> getEnchants() => _enchants != null ? new Dictionary<EnchantmentType, int>(_enchants) { } : new Dictionary<EnchantmentType, int>();
    
    /// <summary>
    /// Checks for the level of the specified enchantment.
    /// </summary>
    /// <param name="enchantment">Enchantment to check</param>
    /// <returns>The level that the specified enchantment has, or 0 if none</returns>
    public int getEnchantLevel(EnchantmentType enchantment)
    {
        if (!hasEnchant(enchantment)) return 0;

        return _enchants[enchantment]; //this cant be invalid, we check above
    }

    /// <summary>
    /// Checks if the specified enchantment conflicts with any enchantments in this ItemMeta.
    /// </summary>
    /// <param name="enchantment">Enchantment to test</param>
    /// <returns>true if the enchantment conflicts, false otherwise</returns>
    public bool hasConflictingEnchant(EnchantmentType enchantment)
    {
        Enchantment enchantmentClass = Enchantment.getByType(enchantment);
        if (enchantmentClass == null) return false; //this should never happen

        foreach (KeyValuePair<EnchantmentType, int> ench in _enchants)
        {
            Enchantment enchClass = Enchantment.getByType(ench.Key);

            if (enchClass == null) continue; //this should never happen

            if (enchClass.conflictsWith(enchantmentClass))
            {
                return true;
            }
        }

        return false;
    }

    /// <summary>
    /// Checks for existence of the specified enchantment.
    /// </summary>
    /// <param name="enchantment">Enchantment to check</param>
    /// <returns>true if this enchantment exists for this meta</returns>
    public bool hasEnchant(EnchantmentType enchantment) => hasEnchants() && _enchants.ContainsKey(enchantment);

    /// <summary>
    /// Checks for the existence of any enchantments.
    /// </summary>
    /// <returns>true if an enchantment exists on this meta</returns>
    public bool hasEnchants() => _enchants != null && _enchants.Count > 0;

    /// <summary>
    /// Sets the enchantments for this item meta.
    /// </summary>
    /// <param name="enchants">The enchantments to set.</param>
    public void setEnchants(Dictionary<EnchantmentType, int>? enchants)
    {
        _enchants = enchants != null ? new Dictionary<EnchantmentType, int>(enchants) : null;
    }


    public ItemMeta clone()
    {
        var copy = new ItemMeta();
        copy._displayName = _displayName;
        copy._enchants = _enchants != null ? new Dictionary<EnchantmentType, int>(_enchants) : null;
        copy._lore = _lore != null ? new List<string>(_lore) : null;
        return copy;
    }

    internal bool isEmpty()
    {
        return _displayName == null && (_lore == null || _lore.Count == 0) && (_enchants == null || _enchants.Count == 0);
    }
}