using System;
using System.Collections.Generic;
using System.Text;

namespace Substrate
{
    /// <summary>
    /// Provides named id values for known enchantment types.
    /// </summary>
    /// <remarks>See <see cref="BlockType"/> for additional information.</remarks>
    public class EnchantmentType
    {
        public const int PROTECTION = 0;
        public const int FIRE_PROTECTION = 1;
        public const int FEATHER_FALLING = 2;
        public const int BLAST_PROTECTION = 3;
        public const int PROJECTILE_PROTECTION = 4;
        public const int RESPIRATION = 5;
        public const int AQUA_AFFINITY = 6;
        public const int SHARPNESS = 16;
        public const int SMITE = 17;
        public const int BANE_OF_ARTHROPODS = 18;
        public const int KNOCKBACK = 19;
        public const int FIRE_ASPECT = 20;
        public const int LOOTING = 21;
        public const int EFFICIENCY = 32;
        public const int SILK_TOUCH = 33;
        public const int UNBREAKING = 34;
        public const int FORTUNE = 35;
    }

    /// <summary>
    /// Provides information on a specific type of enchantment.
    /// </summary>
    /// <remarks>By default, all known MC enchantment types are already defined and registered, assuming Substrate
    /// is up to date with the current MC version.
    /// New enchantment types may be created and used at runtime, and will automatically populate various static lookup tables
    /// in the <see cref="EnchantmentInfo"/> class.</remarks>
    public class EnchantmentInfo
    {
        private static Random _rand = new Random();

        private class CacheTableDict<T> : ICacheTable<T>
        {
            private Dictionary<int, T> _cache;

            public T this[int index]
            {
                get
                {
                    T val;
                    if (_cache.TryGetValue(index, out val)) {
                        return val;
                    }
                    return default(T);
                }
            }

            public CacheTableDict (Dictionary<int, T> cache)
            {
                _cache = cache;
            }
        }

        private static readonly Dictionary<int, EnchantmentInfo> _enchTable;

        private int _id = 0;
        private string _name = "";
        private int _maxLevel = 0;

        private static readonly CacheTableDict<EnchantmentInfo> _enchTableCache;

        /// <summary>
        /// Gets the lookup table for id-to-info values.
        /// </summary>
        public static ICacheTable<EnchantmentInfo> EnchantmentTable
        {
            get { return _enchTableCache; }
        }

        /// <summary>
        /// Gets the id of the enchantment type.
        /// </summary>
        public int ID
        {
            get { return _id; }
        }

        /// <summary>
        /// Gets the name of the enchantment type.
        /// </summary>
        public string Name
        {
            get { return _name; }
        }

        /// <summary>
        /// Gets the maximum level allowed for this enchantment type.
        /// </summary>
        public int MaxLevel
        {
            get { return _maxLevel; }
        }

        /// <summary>
        /// Constructs a new <see cref="EnchantmentInfo"/> record for the given enchantment id.
        /// </summary>
        /// <param name="id">The id of an item type.</param>
        public EnchantmentInfo (int id)
        {
            _id = id;
            _enchTable[_id] = this;
        }

        /// <summary>
        /// Constructs a new <see cref="EnchantmentInfo"/> record for the given enchantment id and name.
        /// </summary>
        /// <param name="id">The id of an item type.</param>
        /// <param name="name">The name of an item type.</param>
        public EnchantmentInfo (int id, string name)
        {
            _id = id;
            _name = name;
            _enchTable[_id] = this;
        }

        /// <summary>
        /// Sets the maximum level for this enchantment type.
        /// </summary>
        /// <param name="level">The maximum allowed level.</param>
        /// <returns>The object instance used to invoke this method.</returns>
        public EnchantmentInfo SetMaxLevel (int level)
        {
            _maxLevel = level;
            return this;
        }

        /// <summary>
        /// Chooses a registered enchantment type at random and returns it.
        /// </summary>
        /// <returns></returns>
        public static EnchantmentInfo GetRandomEnchantment ()
        {
            List<EnchantmentInfo> list = new List<EnchantmentInfo>(_enchTable.Values);
            return list[_rand.Next(list.Count)];
        }

        public static EnchantmentInfo Protection;
        public static EnchantmentInfo FireProtection;
        public static EnchantmentInfo FeatherFalling;
        public static EnchantmentInfo BlastProtection;
        public static EnchantmentInfo ProjectileProtection;
        public static EnchantmentInfo Respiration;
        public static EnchantmentInfo AquaAffinity;
        public static EnchantmentInfo Sharpness;
        public static EnchantmentInfo Smite;
        public static EnchantmentInfo BaneOfArthropods;
        public static EnchantmentInfo Knockback;
        public static EnchantmentInfo FireAspect;
        public static EnchantmentInfo Looting;
        public static EnchantmentInfo Efficiency;
        public static EnchantmentInfo SilkTouch;
        public static EnchantmentInfo Unbreaking;
        public static EnchantmentInfo Fortune;

        static EnchantmentInfo ()
        {
            _enchTable = new Dictionary<int, EnchantmentInfo>();
            _enchTableCache = new CacheTableDict<EnchantmentInfo>(_enchTable);

            Protection = new EnchantmentInfo(EnchantmentType.PROTECTION, "Protection").SetMaxLevel(4);
            FireProtection = new EnchantmentInfo(EnchantmentType.FIRE_PROTECTION, "Fire Protection").SetMaxLevel(4);
            FeatherFalling = new EnchantmentInfo(EnchantmentType.FEATHER_FALLING, "Feather Falling").SetMaxLevel(4);
            BlastProtection = new EnchantmentInfo(EnchantmentType.BLAST_PROTECTION, "Blast Protection").SetMaxLevel(4);
            ProjectileProtection = new EnchantmentInfo(EnchantmentType.PROJECTILE_PROTECTION, "Projectile Protection").SetMaxLevel(4);
            Respiration = new EnchantmentInfo(EnchantmentType.RESPIRATION, "Respiration").SetMaxLevel(3);
            AquaAffinity = new EnchantmentInfo(EnchantmentType.AQUA_AFFINITY, "Aqua Affinity").SetMaxLevel(1);
            Sharpness = new EnchantmentInfo(EnchantmentType.SHARPNESS, "Sharpness").SetMaxLevel(5);
            Smite = new EnchantmentInfo(EnchantmentType.SMITE, "Smite").SetMaxLevel(5);
            BaneOfArthropods = new EnchantmentInfo(EnchantmentType.BANE_OF_ARTHROPODS, "Bane of Arthropods").SetMaxLevel(5);
            Knockback = new EnchantmentInfo(EnchantmentType.KNOCKBACK, "Knockback").SetMaxLevel(2);
            FireAspect = new EnchantmentInfo(EnchantmentType.FIRE_ASPECT, "Fire Aspect").SetMaxLevel(2);
            Looting = new EnchantmentInfo(EnchantmentType.LOOTING, "Looting").SetMaxLevel(3);
            Efficiency = new EnchantmentInfo(EnchantmentType.EFFICIENCY, "Efficiency").SetMaxLevel(5);
            SilkTouch = new EnchantmentInfo(EnchantmentType.SILK_TOUCH, "Silk Touch").SetMaxLevel(1);
            Unbreaking = new EnchantmentInfo(EnchantmentType.UNBREAKING, "Unbreaking").SetMaxLevel(4);
            Fortune = new EnchantmentInfo(EnchantmentType.FORTUNE, "Fortune").SetMaxLevel(3);
        }
    }
}