using System.Collections.Generic;

using UnityEngine;

namespace Colosseum.Skills
{
    /// <summary>
    /// 단일 슬롯에서 사용할 스킬과 장착된 젬 조합입니다.
    /// </summary>
    [System.Serializable]
    public class SkillLoadoutEntry
    {
        private const int DefaultGemSlotCount = 2;

        [Tooltip("이 슬롯의 기반 스킬")]
        [SerializeField] private SkillData baseSkill;
        [Tooltip("기반 스킬에 장착된 젬")]
        [SerializeField] private SkillGemData[] socketedGems = new SkillGemData[DefaultGemSlotCount];

        public SkillData BaseSkill => baseSkill;
        public IReadOnlyList<SkillGemData> SocketedGems => socketedGems;

        public static SkillLoadoutEntry CreateTemporary(SkillData skill)
        {
            SkillLoadoutEntry entry = new SkillLoadoutEntry();
            entry.SetBaseSkill(skill);
            entry.EnsureGemSlotCapacity();
            return entry;
        }

        public SkillLoadoutEntry CreateCopy()
        {
            SkillLoadoutEntry copy = new SkillLoadoutEntry();
            copy.baseSkill = baseSkill;
            copy.socketedGems = new SkillGemData[socketedGems != null ? socketedGems.Length : DefaultGemSlotCount];

            if (socketedGems != null)
            {
                for (int i = 0; i < socketedGems.Length; i++)
                {
                    copy.socketedGems[i] = socketedGems[i];
                }
            }

            return copy;
        }

        public void EnsureGemSlotCapacity(int slotCount = -1)
        {
            if (slotCount < 0)
            {
                slotCount = baseSkill != null ? baseSkill.MaxGemSlotCount : DefaultGemSlotCount;
            }

            slotCount = Mathf.Max(0, slotCount);
            if (socketedGems != null && socketedGems.Length == slotCount)
                return;

            SkillGemData[] resized = new SkillGemData[slotCount];
            if (socketedGems != null)
            {
                int copyCount = Mathf.Min(socketedGems.Length, resized.Length);
                for (int i = 0; i < copyCount; i++)
                {
                    resized[i] = socketedGems[i];
                }
            }

            socketedGems = resized;
        }

        public void SetBaseSkill(SkillData skill)
        {
            baseSkill = skill;
            EnsureGemSlotCapacity();
        }

        public void SetGem(int slotIndex, SkillGemData gem)
        {
            EnsureGemSlotCapacity();
            if (slotIndex < 0 || slotIndex >= socketedGems.Length)
                return;

            socketedGems[slotIndex] = gem;
        }

        public SkillGemData GetGem(int slotIndex)
        {
            EnsureGemSlotCapacity();
            if (slotIndex < 0 || slotIndex >= socketedGems.Length)
                return null;

            return socketedGems[slotIndex];
        }

        public float GetResolvedManaCost()
        {
            if (baseSkill == null)
                return 0f;

            float resolved = baseSkill.ManaCost;
            if (socketedGems == null)
                return resolved;

            for (int i = 0; i < socketedGems.Length; i++)
            {
                SkillGemData gem = socketedGems[i];
                if (gem == null)
                    continue;

                resolved *= gem.ManaCostMultiplier;
            }

            return resolved;
        }

        public float GetResolvedCooldown()
        {
            if (baseSkill == null)
                return 0f;

            float resolved = baseSkill.Cooldown;
            if (socketedGems == null)
                return resolved;

            for (int i = 0; i < socketedGems.Length; i++)
            {
                SkillGemData gem = socketedGems[i];
                if (gem == null)
                    continue;

                resolved *= gem.CooldownMultiplier;
            }

            return resolved;
        }

        public void CollectCastStartEffects(List<SkillEffect> destination)
        {
            if (destination == null)
                return;

            if (baseSkill != null && baseSkill.CastStartEffects != null)
            {
                for (int i = 0; i < baseSkill.CastStartEffects.Count; i++)
                {
                    SkillEffect effect = baseSkill.CastStartEffects[i];
                    if (effect != null)
                        destination.Add(effect);
                }
            }

            if (socketedGems == null)
                return;

            for (int i = 0; i < socketedGems.Length; i++)
            {
                SkillGemData gem = socketedGems[i];
                if (gem == null || gem.CastStartEffects == null)
                    continue;

                for (int j = 0; j < gem.CastStartEffects.Count; j++)
                {
                    SkillEffect effect = gem.CastStartEffects[j];
                    if (effect != null)
                        destination.Add(effect);
                }
            }
        }

        public void CollectTriggeredEffects(Dictionary<int, List<SkillEffect>> destination)
        {
            if (destination == null)
                return;

            if (baseSkill != null && baseSkill.Effects != null)
            {
                for (int i = 0; i < baseSkill.Effects.Count; i++)
                {
                    SkillEffect effect = baseSkill.Effects[i];
                    if (effect == null)
                        continue;

                    AddTriggeredEffect(destination, i, effect);
                }
            }

            if (socketedGems == null)
                return;

            for (int i = 0; i < socketedGems.Length; i++)
            {
                SkillGemData gem = socketedGems[i];
                if (gem == null || gem.TriggeredEffects == null)
                    continue;

                for (int j = 0; j < gem.TriggeredEffects.Count; j++)
                {
                    SkillGemTriggeredEffectEntry entry = gem.TriggeredEffects[j];
                    if (entry == null || entry.Effects == null)
                        continue;

                    for (int k = 0; k < entry.Effects.Count; k++)
                    {
                        SkillEffect effect = entry.Effects[k];
                        if (effect == null)
                            continue;

                        AddTriggeredEffect(destination, entry.TriggerIndex, effect);
                    }
                }
            }
        }

        private static void AddTriggeredEffect(Dictionary<int, List<SkillEffect>> destination, int triggerIndex, SkillEffect effect)
        {
            if (!destination.TryGetValue(triggerIndex, out List<SkillEffect> effectList))
            {
                effectList = new List<SkillEffect>();
                destination.Add(triggerIndex, effectList);
            }

            effectList.Add(effect);
        }
    }
}