using System.Collections.Generic;
using System.Linq;
using UnityEditor;
using UnityEditor.UIElements;
using UnityEngine;
using UnityEngine.UIElements;
using BaseGames.Dialogue;

namespace BaseGames.Editor.Dialogue
{
    /// <summary>
    /// 对话变体预览窗口。
    /// 给定一个 DialogueSequenceSO，模拟世界状态标志的开关组合，
    /// 实时显示各条件变体是否满足，并高亮胜出的变体。
    /// 菜单：BaseGames/Dialogue/Variant Preview
    /// </summary>
    public class DialogueVariantPreviewWindow : EditorWindow
    {
        private DialogueSequenceSO              _target;
        private readonly HashSet<string>        _enabledFlags  = new(System.StringComparer.Ordinal);
        private readonly List<string>           _allFlags      = new();

        private ObjectField         _targetField;
        private VisualElement       _flagContainer;
        private VisualElement       _resultContainer;

        private static readonly Color ColWin      = new(0.20f, 0.75f, 0.35f, 1f);
        private static readonly Color ColFail     = new(0.55f, 0.55f, 0.55f, 1f);
        private static readonly Color ColOverride = new(0.70f, 0.70f, 0.25f, 1f);
        private static readonly Color ColBlocked  = new(0.85f, 0.35f, 0.30f, 1f);

        [MenuItem("BaseGames/Dialogue/Variant Preview")]
        public static void Open()
        {
            var win = GetWindow<DialogueVariantPreviewWindow>("对话变体预览");
            win.minSize = new Vector2(480, 400);
        }

        /// <summary>从外部打开并预填目标 SO。</summary>
        public static void OpenWith(DialogueSequenceSO target)
        {
            var win = GetWindow<DialogueVariantPreviewWindow>("对话变体预览");
            win.minSize = new Vector2(480, 400);
            win.SetTarget(target);
        }

        private void CreateGUI()
        {
            _mockReader = new MockFlagReader(_enabledFlags);
            rootVisualElement.style.paddingLeft   = 10;
            rootVisualElement.style.paddingRight  = 10;
            rootVisualElement.style.paddingTop    = 10;
            rootVisualElement.style.paddingBottom = 10;

            // ── 标题栏 ──
            var header = new Label("对话变体预览工具");
            header.style.fontSize   = 14;
            header.style.unityFontStyleAndWeight = FontStyle.Bold;
            header.style.marginBottom = 8;
            rootVisualElement.Add(header);

            var desc = new Label("在模拟的世界状态标志组合下，预览哪个条件变体会被选中。");
            desc.style.fontSize   = 11;
            desc.style.opacity    = 0.6f;
            desc.style.marginBottom = 10;
            rootVisualElement.Add(desc);

            // ── 目标选择器 ──
            _targetField = new ObjectField("对话序列 SO")
            {
                objectType  = typeof(DialogueSequenceSO),
                allowSceneObjects = false
            };
            _targetField.value = _target;
            _targetField.RegisterValueChangedCallback(evt =>
            {
                SetTarget(evt.newValue as DialogueSequenceSO);
            });
            rootVisualElement.Add(_targetField);

            rootVisualElement.Add(MakeDivider());

            // ── 标志模拟区 ──
            var flagHeader = new Label("模拟世界状态标志");
            flagHeader.style.fontSize   = 12;
            flagHeader.style.unityFontStyleAndWeight = FontStyle.Bold;
            flagHeader.style.marginBottom = 4;
            rootVisualElement.Add(flagHeader);

            _flagContainer = new VisualElement();
            rootVisualElement.Add(_flagContainer);

            rootVisualElement.Add(MakeDivider());

            // ── 变体结果区 ──
            var resultHeader = new Label("变体求值结果");
            resultHeader.style.fontSize   = 12;
            resultHeader.style.unityFontStyleAndWeight = FontStyle.Bold;
            resultHeader.style.marginBottom = 4;
            rootVisualElement.Add(resultHeader);

            var scrollView = new ScrollView(ScrollViewMode.Vertical);
            scrollView.style.flexGrow = 1;
            rootVisualElement.Add(scrollView);

            _resultContainer = new VisualElement();
            scrollView.Add(_resultContainer);

            Rebuild();
        }

        private void SetTarget(DialogueSequenceSO target)
        {
            _target = target;
            _enabledFlags.Clear();
            if (_targetField != null && _targetField.value != target)
                _targetField.SetValueWithoutNotify(target);
            Rebuild();
        }

        // ── 重建 ─────────────────────────────────────────────────────────────

        private void Rebuild()
        {
            RebuildFlagToggles();
            RebuildResults();
        }

        private void RebuildFlagToggles()
        {
            if (_flagContainer == null) return;
            _flagContainer.Clear();
            _allFlags.Clear();

            if (_target == null || _target.variants == null || _target.variants.Length == 0)
            {
                var empty = new Label(_target == null
                    ? "（请选择一个 DialogueSequenceSO）"
                    : "（该序列无条件变体，无需模拟）");
                empty.style.opacity  = 0.5f;
                empty.style.fontSize = 11;
                _flagContainer.Add(empty);
                return;
            }

            // 收集所有变体中涉及的 Flag
            var flagSet = new HashSet<string>(System.StringComparer.Ordinal);
            foreach (var v in _target.variants)
            {
                if (v.requiredFlags != null)
                    foreach (var f in v.requiredFlags)
                        if (!string.IsNullOrEmpty(f)) flagSet.Add(f);
            }
            _allFlags.AddRange(flagSet.OrderBy(x => x));

            if (_allFlags.Count == 0)
            {
                var empty = new Label("（变体未使用任何 requiredFlags）");
                empty.style.opacity  = 0.5f;
                empty.style.fontSize = 11;
                _flagContainer.Add(empty);
                return;
            }

            // 全选 / 全不选 快速按钮
            var btnRow = new VisualElement();
            btnRow.style.flexDirection = FlexDirection.Row;
            btnRow.style.marginBottom  = 4;

            var btnAll = new Button(() =>
            {
                foreach (var f in _allFlags) _enabledFlags.Add(f);
                Rebuild();
            }) { text = "全选" };
            btnAll.style.fontSize = 10;
            btnAll.style.height   = 18;
            btnRow.Add(btnAll);

            var btnNone = new Button(() =>
            {
                _enabledFlags.Clear();
                Rebuild();
            }) { text = "全不选" };
            btnNone.style.fontSize = 10;
            btnNone.style.height   = 18;
            btnRow.Add(btnNone);

            _flagContainer.Add(btnRow);

            // 每个 Flag 对应一个 Toggle
            foreach (var flag in _allFlags)
            {
                bool isOn = _enabledFlags.Contains(flag);
                var toggle = new Toggle(flag) { value = isOn };
                toggle.style.fontSize = 11;
                toggle.RegisterValueChangedCallback(evt =>
                {
                    if (evt.newValue) _enabledFlags.Add(flag);
                    else              _enabledFlags.Remove(flag);
                    RebuildResults();
                });
                _flagContainer.Add(toggle);
            }
        }

        private void RebuildResults()
        {
            if (_resultContainer == null) return;
            _resultContainer.Clear();

            if (_target == null)
                return;

            if (_target.variants == null || _target.variants.Length == 0)
            {
                var msg = new Label("（序列无条件变体，直接使用本序列默认台词）");
                msg.style.opacity  = 0.5f;
                msg.style.fontSize = 11;
                _resultContainer.Add(msg);
                return;
            }

            bool winnerFound = false;

            for (int i = 0; i < _target.variants.Length; i++)
            {
                var variant = _target.variants[i];
                var row     = BuildVariantRow(i, variant, winnerFound);
                _resultContainer.Add(row);

                if (!winnerFound && EvaluateVariant(variant))
                    winnerFound = true;
            }

            // 若无变体胜出，提示将回退到本序列默认台词
            if (!winnerFound)
            {
                var fallback = new Label("↳ 无变体满足，将使用本序列默认台词（无变体覆盖）");
                fallback.style.fontSize   = 11;
                fallback.style.opacity    = 0.6f;
                fallback.style.marginTop  = 4;
                _resultContainer.Add(fallback);
            }
        }

        private VisualElement BuildVariantRow(int index, DialogueSequenceSO.ConditionalVariant variant, bool higherWon)
        {
            bool condMet   = EvaluateVariant(variant);
            bool isWinner  = condMet && !higherWon;

            var card = new VisualElement();
            card.style.borderLeftWidth    = 3;
            card.style.paddingLeft        = 8;
            card.style.paddingRight       = 8;
            card.style.paddingTop         = 5;
            card.style.paddingBottom      = 5;
            card.style.marginBottom       = 4;
            card.style.backgroundColor    = new StyleColor(new Color(0.18f, 0.18f, 0.18f, 1f));

            Color borderColor;
            string statusText;
            Color  statusColor;

            if (isWinner)
            {
                borderColor = ColWin;
                statusText  = "✓ 胜出";
                statusColor = ColWin;
            }
            else if (condMet)
            {
                borderColor = ColOverride;
                statusText  = "⏩ 被更高优先级覆盖";
                statusColor = ColOverride;
            }
            else
            {
                borderColor = ColFail;
                statusText  = "✗ 条件不满足";
                statusColor = ColFail;
            }
            card.style.borderLeftColor = new StyleColor(borderColor);

            // 标题行
            var titleRow = new VisualElement();
            titleRow.style.flexDirection = FlexDirection.Row;
            titleRow.style.alignItems    = Align.Center;
            titleRow.style.marginBottom  = 3;

            var idxLabel = new Label($"变体 {index}");
            idxLabel.style.fontSize   = 11;
            idxLabel.style.flexGrow   = 1;
            idxLabel.style.unityFontStyleAndWeight = isWinner ? FontStyle.Bold : FontStyle.Normal;
            titleRow.Add(idxLabel);

            var seqName = new Label(variant.sequence != null ? variant.sequence.name : "（未设置序列）");
            seqName.style.fontSize = 10;
            seqName.style.opacity  = 0.6f;
            seqName.style.width    = 160;
            titleRow.Add(seqName);

            var statusLabel = new Label(statusText);
            statusLabel.style.fontSize = 10;
            statusLabel.style.color    = new StyleColor(statusColor);
            statusLabel.style.unityFontStyleAndWeight = FontStyle.Bold;
            titleRow.Add(statusLabel);
            card.Add(titleRow);

            // 逻辑类型
            var logicLabel = new Label($"逻辑：{variant.logic}");
            logicLabel.style.fontSize = 10;
            logicLabel.style.opacity  = 0.5f;
            card.Add(logicLabel);

            // 条件详情
            if (variant.requiredFlags != null && variant.requiredFlags.Length > 0)
            {
                foreach (var flag in variant.requiredFlags)
                {
                    if (string.IsNullOrEmpty(flag)) continue;
                    bool flagOn = _enabledFlags.Contains(flag);
                    var flagRow = new VisualElement();
                    flagRow.style.flexDirection = FlexDirection.Row;
                    flagRow.style.alignItems    = Align.Center;
                    flagRow.style.marginTop     = 1;

                    var icon = new Label(flagOn ? "✓" : "✗");
                    icon.style.fontSize = 10;
                    icon.style.color    = new StyleColor(flagOn ? ColWin : ColBlocked);
                    icon.style.width    = 16;
                    flagRow.Add(icon);

                    var flagLabel = new Label(flag);
                    flagLabel.style.fontSize = 10;
                    flagRow.Add(flagLabel);

                    card.Add(flagRow);
                }
            }
            else
            {
                var noFlags = new Label("（无 requiredFlags — 无条件激活）");
                noFlags.style.fontSize = 10;
                noFlags.style.opacity  = 0.5f;
                card.Add(noFlags);
            }

            return card;
        }

        private bool EvaluateVariant(DialogueSequenceSO.ConditionalVariant variant)
        {
            // 使用 DialogueSequenceSO.CheckVariant 统一变体求值逻辑，避免重复实现
            return _target != null && _target.CheckVariant(variant, _mockReader);
        }

        /// <summary>将 _enabledFlags 包装为 IWorldStateReader，供 CheckVariant 调用。</summary>
        private MockFlagReader _mockReader;

        private sealed class MockFlagReader : BaseGames.Core.IWorldStateReader
        {
            private readonly System.Collections.Generic.HashSet<string> _flags;
            public MockFlagReader(System.Collections.Generic.HashSet<string> flags) => _flags = flags;
            public bool HasFlag(string key) => _flags.Contains(key);
        }

        // ── 辅助 ─────────────────────────────────────────────────────────────

        private static VisualElement MakeDivider()
        {
            var d = new VisualElement();
            d.style.height          = 1;
            d.style.backgroundColor = new StyleColor(new Color(0.35f, 0.35f, 0.35f, 0.5f));
            d.style.marginTop       = 6;
            d.style.marginBottom    = 6;
            return d;
        }
    }
}