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

using UnityEngine;

using Colosseum.Passives;
using Colosseum.Skills;
using Colosseum.Weapons;

namespace Colosseum.Combat.Simulation
{
    /// <summary>
    /// 허수아비 계산 시뮬레이터가 사용할 완성형 빌드 입력값입니다.
    /// 프리셋 없이 직접 구성한 빌드와 기존 프리셋 기반 입력을 모두 지원합니다.
    /// </summary>
    [System.Serializable]
    public class BuildSimulationInput
    {
        private const int DefaultSlotCount = 7;

        [Header("Label")]
        [SerializeField] private string buildName = "새 빌드";

        [Header("Stats")]
        [Min(0f)] [SerializeField] private float strength = 10f;
        [Min(0f)] [SerializeField] private float dexterity = 10f;
        [Min(0f)] [SerializeField] private float intelligence = 10f;
        [Min(0f)] [SerializeField] private float vitality = 10f;
        [Min(0f)] [SerializeField] private float wisdom = 10f;
        [Min(0f)] [SerializeField] private float spirit = 10f;

        [Header("Build Assets")]
        [SerializeField] private WeaponData weapon;

        [Header("Direct Build")]
        [Tooltip("직접 구성한 스킬/젬 슬롯입니다. 비어 있으면 로드아웃 프리셋을 사용합니다.")]
        [SerializeField] private SkillLoadoutEntry[] directSkillSlots = new SkillLoadoutEntry[DefaultSlotCount];
        [Tooltip("직접 구성한 패시브 트리입니다. 비어 있으면 패시브 프리셋의 트리를 사용합니다.")]
        [SerializeField] private PassiveTreeData passiveTree;
        [Tooltip("직접 선택한 패시브 노드 목록입니다. 비어 있으면 패시브 프리셋의 선택 노드를 사용합니다.")]
        [SerializeField] private List<PassiveNodeData> selectedPassiveNodes = new List<PassiveNodeData>();

        [Header("Preset Fallback")]
        [SerializeField] private PassivePresetData passivePreset;
        [SerializeField] private PlayerLoadoutPreset loadoutPreset;

        public string BuildName => string.IsNullOrWhiteSpace(buildName) ? "새 빌드" : buildName.Trim();
        public float Strength => strength;
        public float Dexterity => dexterity;
        public float Intelligence => intelligence;
        public float Vitality => vitality;
        public float Wisdom => wisdom;
        public float Spirit => spirit;
        public WeaponData Weapon => weapon;
        public PassiveTreeData PassiveTree => passiveTree;
        public IReadOnlyList<PassiveNodeData> SelectedPassiveNodes => selectedPassiveNodes;
        public PassivePresetData PassivePreset => passivePreset;
        public PlayerLoadoutPreset LoadoutPreset => loadoutPreset;

        /// <summary>
        /// 입력 상태를 읽기 쉬운 라벨로 구성합니다.
        /// </summary>
        public string BuildLabel
        {
            get
            {
                string passiveName = ResolvePassiveLabel();
                string loadoutName = ResolveLoadoutLabel();
                return $"{BuildName} | Passive={passiveName} | Loadout={loadoutName}";
            }
        }

        /// <summary>
        /// 직접 구성 슬롯과 프리셋을 합쳐 실제 계산에 사용할 슬롯 배열을 반환합니다.
        /// </summary>
        public IReadOnlyList<SkillLoadoutEntry> ResolveLoadoutEntries()
        {
            EnsureDirectSlotCapacity();

            if (HasDirectSkillSetup())
                return directSkillSlots;

            return loadoutPreset != null ? loadoutPreset.Slots : System.Array.Empty<SkillLoadoutEntry>();
        }

        /// <summary>
        /// 실제 계산 가능한 기반 스킬이 하나 이상 있는지 반환합니다.
        /// </summary>
        public bool HasAnyResolvedSkill()
        {
            IReadOnlyList<SkillLoadoutEntry> entries = ResolveLoadoutEntries();
            for (int i = 0; i < entries.Count; i++)
            {
                if (entries[i] != null && entries[i].BaseSkill != null)
                    return true;
            }

            return false;
        }

        /// <summary>
        /// 실제 계산에 사용할 패시브 트리를 반환합니다.
        /// </summary>
        public PassiveTreeData ResolvePassiveTree()
        {
            if (passiveTree != null)
                return passiveTree;

            return passivePreset != null ? passivePreset.Tree : null;
        }

        /// <summary>
        /// 실제 계산에 사용할 패시브 노드 ID 목록을 반환합니다.
        /// </summary>
        public List<string> BuildSelectedPassiveNodeIdList()
        {
            List<string> nodeIds = new List<string>();

            IReadOnlyList<PassiveNodeData> resolvedNodes = ResolveSelectedPassiveNodes();
            for (int i = 0; i < resolvedNodes.Count; i++)
            {
                PassiveNodeData node = resolvedNodes[i];
                if (node == null || string.IsNullOrWhiteSpace(node.NodeId))
                    continue;

                nodeIds.Add(node.NodeId);
            }
            return nodeIds;
        }

        /// <summary>
        /// 실제 계산에 사용할 패시브 노드 목록을 반환합니다.
        /// </summary>
        public IReadOnlyList<PassiveNodeData> ResolveSelectedPassiveNodes()
        {
            if (selectedPassiveNodes != null && selectedPassiveNodes.Count > 0)
                return selectedPassiveNodes;

            return passivePreset != null ? passivePreset.SelectedNodes : System.Array.Empty<PassiveNodeData>();
        }

        /// <summary>
        /// 직접 구성 슬롯을 덮어씁니다.
        /// </summary>
        public void SetDirectSkillSlots(IReadOnlyList<SkillLoadoutEntry> entries)
        {
            EnsureDirectSlotCapacity();

            for (int i = 0; i < directSkillSlots.Length; i++)
            {
                directSkillSlots[i] = null;
            }

            if (entries == null)
                return;

            int copyCount = Mathf.Min(entries.Count, directSkillSlots.Length);
            for (int i = 0; i < copyCount; i++)
            {
                SkillLoadoutEntry entry = entries[i];
                directSkillSlots[i] = entry != null ? entry.CreateCopy() : null;
            }
        }

        /// <summary>
        /// 직접 구성 패시브를 덮어씁니다.
        /// </summary>
        public void SetDirectPassiveSelection(PassiveTreeData tree, IReadOnlyList<PassiveNodeData> nodes)
        {
            passiveTree = tree;
            selectedPassiveNodes.Clear();

            if (nodes == null)
                return;

            for (int i = 0; i < nodes.Count; i++)
            {
                if (nodes[i] != null)
                    selectedPassiveNodes.Add(nodes[i]);
            }
        }

        /// <summary>
        /// 빌드 이름을 갱신합니다.
        /// </summary>
        public void SetBuildName(string value)
        {
            buildName = value ?? string.Empty;
        }

        /// <summary>
        /// 현재 입력값의 복사본을 생성합니다.
        /// </summary>
        public BuildSimulationInput CreateCopy()
        {
            EnsureDirectSlotCapacity();

            BuildSimulationInput copy = new BuildSimulationInput
            {
                buildName = buildName,
                strength = strength,
                dexterity = dexterity,
                intelligence = intelligence,
                vitality = vitality,
                wisdom = wisdom,
                spirit = spirit,
                weapon = weapon,
                passiveTree = passiveTree,
                passivePreset = passivePreset,
                loadoutPreset = loadoutPreset,
            };

            copy.directSkillSlots = new SkillLoadoutEntry[directSkillSlots.Length];
            for (int i = 0; i < directSkillSlots.Length; i++)
            {
                copy.directSkillSlots[i] = directSkillSlots[i] != null ? directSkillSlots[i].CreateCopy() : null;
            }

            copy.selectedPassiveNodes = new List<PassiveNodeData>(selectedPassiveNodes.Count);
            for (int i = 0; i < selectedPassiveNodes.Count; i++)
            {
                if (selectedPassiveNodes[i] != null)
                    copy.selectedPassiveNodes.Add(selectedPassiveNodes[i]);
            }

            return copy;
        }

        private bool HasDirectSkillSetup()
        {
            if (directSkillSlots == null)
                return false;

            for (int i = 0; i < directSkillSlots.Length; i++)
            {
                if (directSkillSlots[i] != null && directSkillSlots[i].BaseSkill != null)
                    return true;
            }

            return false;
        }

        private void EnsureDirectSlotCapacity()
        {
            if (directSkillSlots != null && directSkillSlots.Length == DefaultSlotCount)
                return;

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

            directSkillSlots = resized;
        }

        private string ResolvePassiveLabel()
        {
            if (selectedPassiveNodes != null && selectedPassiveNodes.Count > 0)
                return BuildPassiveNodeSummary(selectedPassiveNodes);

            if (passivePreset != null && !string.IsNullOrWhiteSpace(passivePreset.PresetName))
                return passivePreset.PresetName;

            return "패시브 없음";
        }

        private string ResolveLoadoutLabel()
        {
            if (HasDirectSkillSetup())
                return BuildLoadoutSummary(directSkillSlots);

            if (loadoutPreset != null && !string.IsNullOrWhiteSpace(loadoutPreset.PresetName))
                return loadoutPreset.PresetName;

            return "로드아웃 없음";
        }

        private static string BuildPassiveNodeSummary(IReadOnlyList<PassiveNodeData> nodes)
        {
            StringBuilder builder = new StringBuilder();
            for (int i = 0; i < nodes.Count; i++)
            {
                PassiveNodeData node = nodes[i];
                if (node == null)
                    continue;

                if (builder.Length > 0)
                    builder.Append('+');

                builder.Append(string.IsNullOrWhiteSpace(node.DisplayName) ? node.name : node.DisplayName);
            }

            return builder.Length > 0 ? builder.ToString() : "패시브 없음";
        }

        private static string BuildLoadoutSummary(IReadOnlyList<SkillLoadoutEntry> entries)
        {
            StringBuilder builder = new StringBuilder();
            for (int i = 0; i < entries.Count; i++)
            {
                SkillLoadoutEntry entry = entries[i];
                if (entry == null || entry.BaseSkill == null)
                    continue;

                if (builder.Length > 0)
                    builder.Append(" / ");

                builder.Append('S');
                builder.Append(i);
                builder.Append('=');
                builder.Append(entry.BaseSkill.SkillName);

                bool hasGem = false;
                IReadOnlyList<SkillGemData> gems = entry.SocketedGems;
                for (int gemIndex = 0; gemIndex < gems.Count; gemIndex++)
                {
                    SkillGemData gem = gems[gemIndex];
                    if (gem == null)
                        continue;

                    builder.Append(hasGem ? '+' : '[');
                    builder.Append(gem.GemName);
                    hasGem = true;
                }

                if (hasGem)
                    builder.Append(']');
            }

            return builder.Length > 0 ? builder.ToString() : "직접구성";
        }
    }
}