using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

namespace TKS
{
    /// <summary>화면 HUD(uGUI · 코드 생성): 스테이지·턴·유닛 수·안내·선택 유닛 정보·미니맵·스킬 아이콘(추후)·결과 오버레이.</summary>
    public class BattleHUD : MonoBehaviour
    {
        BattleManager battle;
        Camera uiCam;
        CameraController camCtrl;
        Text stageText;
        Text turnText;
        Text countText;
        Text messageText;
        Text hintText;
        Text unitText;
        GameObject resultOverlay;
        Text resultTitle;
        Text resultSub;
        Unit selected;

        Image minimapBg;
        Image minimapView;
        readonly Dictionary<Unit, Image> minimapDots = new Dictionary<Unit, Image>();

        public void Build(BattleManager b, Camera cam, CameraController cc)
        {
            battle = b;
            uiCam = cam;
            camCtrl = cc;
            var canvas = gameObject.AddComponent<Canvas>();
            canvas.renderMode = RenderMode.ScreenSpaceCamera;
            canvas.worldCamera = cam;
            canvas.planeDistance = 1f;
            canvas.sortingOrder = 100;
            var scaler = gameObject.AddComponent<CanvasScaler>();
            scaler.uiScaleMode = CanvasScaler.ScaleMode.ScaleWithScreenSize;
            scaler.referenceResolution = new Vector2(1080f, 1920f);
            scaler.matchWidthOrHeight = 0.5f;
            gameObject.AddComponent<GraphicRaycaster>();

            if (EventSystem.current == null && FindFirstObjectByType<EventSystem>() == null)
            {
                var es = new GameObject("EventSystem");
                es.AddComponent<EventSystem>();
                es.AddComponent<StandaloneInputModule>();
            }

            stageText = MakeText("Stage", new Vector2(0f, 1f), new Vector2(0f, 1f), new Vector2(0f, 1f), new Vector2(30f, -28f), new Vector2(760f, 70f), 40, TextAnchor.UpperLeft);
            countText = MakeText("Count", new Vector2(1f, 1f), new Vector2(1f, 1f), new Vector2(1f, 1f), new Vector2(-30f, -28f), new Vector2(520f, 70f), 36, TextAnchor.UpperRight);
            turnText = MakeText("Turn", new Vector2(0.5f, 1f), new Vector2(0.5f, 1f), new Vector2(0.5f, 1f), new Vector2(0f, -92f), new Vector2(700f, 70f), 46, TextAnchor.UpperCenter);
            turnText.color = new Color(1f, 0.95f, 0.6f);
            messageText = MakeText("Message", new Vector2(0.5f, 1f), new Vector2(0.5f, 1f), new Vector2(0.5f, 1f), new Vector2(0f, -160f), new Vector2(1040f, 60f), 30, TextAnchor.UpperCenter);
            messageText.color = new Color(0.9f, 0.95f, 1f);

            hintText = MakeText("Hint", new Vector2(0.5f, 0f), new Vector2(0.5f, 0f), new Vector2(0.5f, 0f), new Vector2(0f, 36f), new Vector2(1040f, 60f), 28, TextAnchor.LowerCenter);
            hintText.color = new Color(0.85f, 0.85f, 0.85f);
            unitText = MakeText("UnitInfo", new Vector2(0f, 0f), new Vector2(0f, 0f), new Vector2(0f, 0f), new Vector2(30f, 110f), new Vector2(760f, 170f), 32, TextAnchor.LowerLeft);

            // 스킬 아이콘(초기 단계 미구현 · 자리만)
            var skill = MakeImage("SkillIcon", transform, new Vector2(1f, 0f), new Vector2(1f, 0f), new Vector2(1f, 0f), new Vector2(-36f, 110f), new Vector2(170f, 170f), new Color(0.3f, 0.3f, 0.33f, 0.8f));
            var skillLabel = MakeText("Label", new Vector2(0f, 0f), new Vector2(1f, 1f), new Vector2(0.5f, 0.5f), Vector2.zero, Vector2.zero, 30, TextAnchor.MiddleCenter);
            skillLabel.transform.SetParent(skill.transform, false);
            skillLabel.text = "스킬\n(추후)";
            skillLabel.color = new Color(0.75f, 0.75f, 0.75f);

            // 미니맵 (전장 비율 · 탭하면 그 지점으로 카메라 이동)
            Vector2 bs = battle.Config.boardSize;
            float mmW = 180f;
            float mmH = mmW * bs.y / Mathf.Max(0.01f, bs.x);
            minimapBg = MakeImage("Minimap", transform, new Vector2(1f, 1f), new Vector2(1f, 1f), new Vector2(1f, 1f), new Vector2(-30f, -215f), new Vector2(mmW, mmH), new Color(0.06f, 0.1f, 0.06f, 0.8f));
            var mmBorder = MakeImage("Border", minimapBg.transform, Vector2.zero, Vector2.one, new Vector2(0.5f, 0.5f), Vector2.zero, new Vector2(6f, 6f), new Color(0.85f, 0.75f, 0.45f, 0.9f));
            mmBorder.transform.SetAsFirstSibling();
            var mmMid = MakeImage("Mid", minimapBg.transform, new Vector2(0f, 0.5f), new Vector2(1f, 0.5f), new Vector2(0.5f, 0.5f), Vector2.zero, new Vector2(0f, 2f), new Color(1f, 1f, 1f, 0.25f));
            minimapView = MakeImage("View", minimapBg.transform, Vector2.zero, Vector2.zero, Vector2.zero, Vector2.zero, new Vector2(40f, 60f), new Color(1f, 1f, 1f, 0.2f));

            resultOverlay = MakeImage("ResultOverlay", transform, Vector2.zero, Vector2.one, new Vector2(0.5f, 0.5f), Vector2.zero, Vector2.zero, new Color(0f, 0f, 0f, 0.65f)).gameObject;
            resultTitle = MakeText("Title", new Vector2(0.5f, 0.5f), new Vector2(0.5f, 0.5f), new Vector2(0.5f, 0.5f), new Vector2(0f, 60f), new Vector2(1000f, 160f), 110, TextAnchor.MiddleCenter);
            resultTitle.transform.SetParent(resultOverlay.transform, false);
            resultSub = MakeText("Sub", new Vector2(0.5f, 0.5f), new Vector2(0.5f, 0.5f), new Vector2(0.5f, 0.5f), new Vector2(0f, -80f), new Vector2(1000f, 120f), 40, TextAnchor.MiddleCenter);
            resultSub.transform.SetParent(resultOverlay.transform, false);
            resultOverlay.SetActive(false);
        }

        Text MakeText(string name, Vector2 anchorMin, Vector2 anchorMax, Vector2 pivot, Vector2 anchoredPos, Vector2 size, int fontSize, TextAnchor align)
        {
            var go = new GameObject(name);
            go.transform.SetParent(transform, false);
            var rt = go.AddComponent<RectTransform>();
            rt.anchorMin = anchorMin;
            rt.anchorMax = anchorMax;
            rt.pivot = pivot;
            rt.anchoredPosition = anchoredPos;
            rt.sizeDelta = size;
            var t = go.AddComponent<Text>();
            t.font = TextUtil.Font;
            t.fontSize = fontSize;
            t.alignment = align;
            t.color = Color.white;
            t.horizontalOverflow = HorizontalWrapMode.Overflow;
            t.verticalOverflow = VerticalWrapMode.Overflow;
            t.raycastTarget = false;
            var sh = go.AddComponent<Shadow>();
            sh.effectDistance = new Vector2(2f, -2f);
            sh.effectColor = new Color(0f, 0f, 0f, 0.8f);
            return t;
        }

        Image MakeImage(string name, Transform parent, Vector2 anchorMin, Vector2 anchorMax, Vector2 pivot, Vector2 anchoredPos, Vector2 size, Color color)
        {
            var go = new GameObject(name);
            go.transform.SetParent(parent, false);
            var rt = go.AddComponent<RectTransform>();
            rt.anchorMin = anchorMin;
            rt.anchorMax = anchorMax;
            rt.pivot = pivot;
            rt.anchoredPosition = anchoredPos;
            rt.sizeDelta = size;
            var img = go.AddComponent<Image>();
            img.color = color;
            img.raycastTarget = false;
            return img;
        }

        public void SetSelected(Unit u)
        {
            selected = u;
        }

        /// <summary>화면 점이 미니맵 안이면 해당 월드 좌표를 돌려준다.</summary>
        public bool TryMinimapTap(Vector2 screen, out Vector2 world)
        {
            world = Vector2.zero;
            if (minimapBg == null || battle == null || battle.Board == null) return false;
            var rt = minimapBg.rectTransform;
            if (!RectTransformUtility.RectangleContainsScreenPoint(rt, screen, uiCam)) return false;
            Vector2 local;
            if (!RectTransformUtility.ScreenPointToLocalPointInRectangle(rt, screen, uiCam, out local)) return false;
            var r = rt.rect;
            float nx = Mathf.Clamp01((local.x - r.xMin) / r.width);
            float ny = Mathf.Clamp01((local.y - r.yMin) / r.height);
            var b = battle.Board.Rect;
            world = new Vector2(b.xMin + nx * b.width, b.yMin + ny * b.height);
            return true;
        }

        void LateUpdate()
        {
            if (battle == null || battle.Config == null || battle.Config.stages.Length == 0) return;
            Refresh();
            RefreshMinimap();
        }

        void Refresh()
        {
            var stage = battle.Stage;
            stageText.text = "제" + (battle.StageIndex + 1) + "전투 · " + stage.title + (string.IsNullOrEmpty(stage.subtitle) ? "" : "  " + stage.subtitle);
            countText.text = "아군 " + battle.AliveCount(Faction.Player) + " · 적 " + battle.AliveCount(Faction.Enemy);

            switch (battle.Phase)
            {
                case BattlePhase.PlayerTurn: turnText.text = "아군 턴 " + battle.TurnNumber; break;
                case BattlePhase.Resolving: turnText.text = "진행 중…"; break;
                case BattlePhase.EnemyTurn: turnText.text = "적군 턴 " + battle.TurnNumber; break;
                case BattlePhase.StageClear: turnText.text = "승리"; break;
                case BattlePhase.Defeat: turnText.text = "패배"; break;
                default: turnText.text = ""; break;
            }
            messageText.text = battle.LastMessage;

            if (battle.Phase == BattlePhase.PlayerTurn)
            {
                hintText.text = battle.OnlyBonusMovesRemain()
                    ? "추가 이동: 유닛을 당겨 이동 · 빈 곳을 탭하면 건너뜀"
                    : "유닛을 잡고 뒤로 당겼다 놓기 = 이동·공격 · 유닛 탭 = 사거리 · 빈 곳 드래그 = 전장 이동";
            }
            else
            {
                hintText.text = "";
            }

            if (selected != null && selected.IsAlive)
            {
                var u = selected;
                string side = u.Faction == Faction.Player ? "아군" : "적군";
                string line1 = side + " · " + u.DisplayName + " · " + UnitTypeInfo.Korean(u.Type) + (u.IsBoss ? " (장수)" : "");
                string line2 = "HP " + u.Hp + "/" + u.MaxHp + "   공 " + u.Atk + "   방 " + u.Def;
                string line3 = "슬링 " + u.SlingMaxDistance.ToString("0.#");
                if (u.Type == UnitType.Archer) line3 += "   사거리 " + u.AttackRange.ToString("0.#") + " (슬링 +" + Mathf.RoundToInt(battle.Config.archerRangeRatio * 100f) + " %)";
                if (u.Type == UnitType.Spear) line3 += "   견제 반경 " + u.AttackRange.ToString("0.#");
                string state = "";
                if (u.Faction == Faction.Player)
                {
                    if (u.BonusMoveAvailable) state = "   [추가 이동]";
                    else if (u.ActedThisTurn) state = "   [행동 완료]";
                }
                if (u.Overwatch) state += "   [대기 중]";
                unitText.text = line1 + "\n" + line2 + "\n" + line3 + state;
            }
            else
            {
                unitText.text = "유닛을 선택하세요";
            }

            bool result = battle.Phase == BattlePhase.StageClear || battle.Phase == BattlePhase.Defeat;
            if (resultOverlay.activeSelf != result) resultOverlay.SetActive(result);
            if (result)
            {
                bool win = battle.Phase == BattlePhase.StageClear;
                resultTitle.text = win ? "승리" : "패배";
                resultTitle.color = win ? new Color(1f, 0.9f, 0.4f) : new Color(1f, 0.5f, 0.5f);
                resultSub.text = win
                    ? stage.title + " 제압!\n화면을 탭하면 다음 전투로"
                    : stage.title + " 에서 패배\n화면을 탭하면 다시 도전";
            }
        }

        void RefreshMinimap()
        {
            if (minimapBg == null || battle.Board == null) return;
            var r = minimapBg.rectTransform.rect;
            var b = battle.Board.Rect;
            float sx = r.width / b.width;
            float sy = r.height / b.height;

            // 카메라 시야 사각형
            if (camCtrl != null)
            {
                var v = camCtrl.ViewRect;
                float x0 = Mathf.Clamp((v.xMin - b.xMin) * sx, 0f, r.width);
                float y0 = Mathf.Clamp((v.yMin - b.yMin) * sy, 0f, r.height);
                float x1 = Mathf.Clamp((v.xMax - b.xMin) * sx, 0f, r.width);
                float y1 = Mathf.Clamp((v.yMax - b.yMin) * sy, 0f, r.height);
                minimapView.rectTransform.anchoredPosition = new Vector2(x0, y0);
                minimapView.rectTransform.sizeDelta = new Vector2(Mathf.Max(2f, x1 - x0), Mathf.Max(2f, y1 - y0));
            }

            // 유닛 점
            foreach (var u in battle.Units)
            {
                if (u == null) continue;
                Image dot;
                if (!minimapDots.TryGetValue(u, out dot))
                {
                    dot = MakeImage("Dot", minimapBg.transform, Vector2.zero, Vector2.zero, new Vector2(0.5f, 0.5f), Vector2.zero,
                        new Vector2(u.IsBoss ? 14f : 10f, u.IsBoss ? 14f : 10f),
                        u.Faction == Faction.Player ? UnitView.PlayerColor : UnitView.EnemyColor);
                    if (u.IsBoss) dot.color = new Color(1f, 0.85f, 0.3f);
                    minimapDots[u] = dot;
                }
                bool show = u.IsAlive;
                if (dot.gameObject.activeSelf != show) dot.gameObject.SetActive(show);
                if (show) dot.rectTransform.anchoredPosition = new Vector2((u.Position.x - b.xMin) * sx, (u.Position.y - b.yMin) * sy);
            }
            // 사라진 유닛 정리
            var dead = new List<Unit>();
            foreach (var kv in minimapDots)
            {
                if (kv.Key == null) dead.Add(kv.Key);
            }
            foreach (var k in dead)
            {
                if (minimapDots[k] != null) Destroy(minimapDots[k].gameObject);
                minimapDots.Remove(k);
            }
        }
    }
}