using System;
using System.Collections.Generic;
using Sirenix.OdinInspector;
using UnityEngine;

namespace Ichni.Story
{
    /// <summary>
    /// Block 在故事树中的状态：已锁定、当前可交互、已完成。
    /// </summary>
    public enum StoryBlockState
    {
        Locked,
        Current,
        Completed
    }

    /// <summary>
    /// Block 的类型，决定点击后触发的行为。
    /// </summary>
    public enum StoryBlockType
    {
        Text,
        Song,
        Tutorial
    }

    /// <summary>
    /// 变量条件的比较方式。
    /// </summary>
    public enum VariableComparison
    {
        Equal,
        NotEqual,
        Greater,
        GreaterOrEqual,
        Less,
        LessOrEqual
    }

    /// <summary>
    /// 故事树中单个 block 的完整数据定义，由 <see cref="StoryData"/> 持有。
    /// </summary>
    [InlineProperty]
    [Serializable]
    public class StoryBlockDefinition
    {
        [FoldoutGroup("$blockId", false)]
        [LabelText("Block ID")]
        public string blockId;

        [FoldoutGroup("$blockId")]
        [LabelText("Type")]
        public StoryBlockType blockType;

        [FoldoutGroup("$blockId")]
        [LabelText("Grid Column")]
        [Tooltip("故事树网格中的列：向右为正，(0,0) 位于容器左侧中部。可为负数与小数（用于微调）。")]
        public float gridColumn;

        [FoldoutGroup("$blockId")]
        [LabelText("Grid Row")]
        [Tooltip("故事树网格中的行：向下为正、向上为负，0 对应垂直中线。可为小数（用于微调）。")]
        public float gridRow;

        [FoldoutGroup("$blockId")]
        [LabelText("Next Block IDs")]
        public List<string> nextBlockIds = new List<string>();

        [FoldoutGroup("$blockId")]
        [LabelText("Unlock Condition")]
        public UnlockCondition unlockCondition = new UnlockCondition();

        // ── Text Block ──────────────────────────────────────────────────────────

        [FoldoutGroup("$blockId")]
        [ShowIf("blockType", StoryBlockType.Text)]
        [LabelText("Yarn Node Name")]
        public string yarnNodeName;

        [FoldoutGroup("$blockId")]
        [ShowIf("blockType", StoryBlockType.Text)]
        [LabelText("Title Key (Localization)")]
        public string titleKey;

        // ── Song Block ──────────────────────────────────────────────────────────

        [FoldoutGroup("$blockId")]
        [ShowIf("blockType", StoryBlockType.Song)]
        [LabelText("Song Name")]
        public string songName;

        // ── Tutorial Block ──────────────────────────────────────────────────────

        [FoldoutGroup("$blockId")]
        [ShowIf("blockType", StoryBlockType.Tutorial)]
        [LabelText("Tutorial Name")]
        public string tutorialName;

        /// <summary>
        /// 预览 / 调试用的显示标题：按类型取对应字段，缺省时回退到 blockId。
        /// </summary>
        public string GetDisplayTitle()
        {
            string title = blockType switch
            {
                StoryBlockType.Text     => titleKey,
                StoryBlockType.Song     => songName,
                StoryBlockType.Tutorial => tutorialName,
                _                       => null
            };

            return string.IsNullOrEmpty(title) ? blockId : title;
        }
    }

    /// <summary>
    /// Block 的解锁条件。以一棵可组合的条件树（<see cref="StoryConditionNode"/>）表达，
    /// 支持"与 / 或 / 非 + 叶子条件"的任意嵌套。根节点为空时视为无条件解锁（始终满足）。
    /// </summary>
    [InlineProperty]
    [Serializable]
    public class UnlockCondition
    {
        [HideLabel]
        [SerializeReference]
        [InfoBox("留空表示无条件解锁（章节起始即可用）。可选择 All Of(AND) / Any Of(OR) / Not 复合节点进行任意嵌套。")]
        public StoryConditionNode root;

        /// <summary>
        /// 检查解锁条件是否满足。根节点为空视为满足。
        /// </summary>
        /// <param name="getVariable">按变量名返回其整型值的委托。</param>
        /// <param name="isBlockCompleted">按 blockId 判断该 block 是否已完成的委托。</param>
        public bool IsSatisfied(Func<string, int> getVariable, Func<string, bool> isBlockCompleted)
        {
            return root == null || root.Evaluate(getVariable, isBlockCompleted);
        }
    }
}