using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

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

        public void Build(BattleManager b, Camera cam)
        {
            battle = b;
            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);

            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;
        }

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

        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"
                    : "아군 유닛을 잡고 뒤로 당겼다 놓으면 반대 방향으로 이동·공격";
            }
            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.#") + (u.Type == UnitType.Archer ? "   사거리 " + u.AttackRange.ToString("0.#") : "") + (u.Type == UnitType.Spear ? "   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";
            }
        }
    }
}