using System;
using System.Collections.Generic;
using System.IO;
using System.Text.Json;
using System.Text.Json.Serialization;
using Godot;
using Models;

/// <summary>
/// 校园行为系统使用的位置标识符。
/// 这些标识符映射到 campus.tscn 中的 Node2D 标记点，以便 AI 可以通过名称选择目标。
/// </summary>
public enum CampusLocationId
{
	None,
	Laboratory,           // 实验室
	Library,              // 图书馆
	Canteen,              // 食堂
	Dormitory,            // 宿舍
	ArtificialLake,       // 人工湖
	CoffeeShop,           // 咖啡店
	AdministrationBuilding, // 行政楼
	FootballField,        // 足球场
	RandomWander          // 随机漫游
}

/// <summary>
/// 行为规划器和状态机使用的动作标识符。
/// 每个动作通过 campus_behavior.json 配置持续时间和属性变化。
/// </summary>
public enum CampusActionId
{
	None,
	Experimenting,        // 做实验
	Writing,              // 写作
	Eating,               // 吃饭
	Sleeping,             // 睡觉
	Chilling,             // 放松/闲逛
	Staring,              // 发呆
	CoffeeBreak,          // 喝咖啡
	Administration,       // 行政工作
	Running,              // 跑步
	Socializing,          // 社交
	Wandering             // 漫步
}

/// <summary>
/// 优先级级别，对应设计文档中的顺序：值越小优先级越高。
/// </summary>
public enum CampusBehaviorPriority
{
	Critical = 0,     // 紧急状态（崩溃/力竭）
	AssignedTask = 1, // 指派任务
	Needs = 2,        // 基础需求（饿/累/社交）
	Trait = 3,        // 特质驱动（性格偏好）
	Idle = 4          // 闲置
}

/// <summary>
/// 校园演示的最小化任务类型。这些不是完整的游戏任务，
/// 仅用于驱动 AI 的“指派任务”优先级。
/// </summary>
public enum CampusTaskType
{
	Experiment,     // 实验
	Writing,        // 写作
	Administration, // 行政
	Exercise,       // 锻炼
	Coding,         // 编程
	Social          // 社交
}

/// <summary>
/// 从 JSON 加载的动作配置。
/// 变化量（Delta）在动作运行时按秒应用，因此动作越长积累的效果越多。
/// </summary>
public sealed class CampusActionConfig
{
	public CampusActionId ActionId { get; set; }
	public CampusLocationId LocationId { get; set; }
	public float DurationSeconds { get; set; }
	public float HungerDelta { get; set; }
	public float EnergyDelta { get; set; }
	public float StaminaDelta { get; set; }
	public float StressDelta { get; set; }
	public float MoodDelta { get; set; }
	public float SocialDelta { get; set; }
	public float SanityDelta { get; set; }
	public float HealthDelta { get; set; }
}

/// <summary>
/// 校园 AI 的全局行为配置。
/// 这是数据驱动的，以便在不修改代码的情况下通过 JSON 进行平衡调整。
/// </summary>
public sealed class CampusBehaviorConfig
{
	public float CriticalSanityThreshold { get; set; } = 15f;
	public float CriticalStaminaThreshold { get; set; } = 12f;
	public float CriticalStressThreshold { get; set; } = 90f;
	public float HungerThreshold { get; set; } = 30f;
	public float EnergyThreshold { get; set; } = 25f;
	public float SocialThreshold { get; set; } = 35f;
	public float LowMoodThreshold { get; set; } = 25f;
	public float HungerDecayPerSecond { get; set; } = 0.6f;
	public float EnergyDecayPerSecond { get; set; } = 0.5f;
	public float StaminaDecayPerSecond { get; set; } = 0.4f;
	public float StressGrowthPerSecond { get; set; } = 0.45f;
	public float SocialDecayPerSecond { get; set; } = 0.35f;
	public float DecisionIntervalSeconds { get; set; } = 0.5f;
	public float ActionDurationVariance { get; set; } = 0.25f;
	public float MinPlannedActionSeconds { get; set; } = 2.0f;
	public List<CampusActionConfig> ActionConfigs { get; set; } = new();

	private readonly Dictionary<CampusActionId, CampusActionConfig> _actionLookup = new();

	public CampusActionConfig GetActionConfig(CampusActionId id)
	{
		if (_actionLookup.Count == 0)
		{
			BuildLookup();
		}

		return _actionLookup.TryGetValue(id, out var config) ? config : null;
	}

	private void BuildLookup()
	{
		_actionLookup.Clear();
		if (ActionConfigs == null) return;
		foreach (var config in ActionConfigs)
		{
			_actionLookup[config.ActionId] = config;
		}
	}

	public static CampusBehaviorConfig Load(string path)
	{
		if (string.IsNullOrWhiteSpace(path))
		{
			GD.PushWarning("Campus behavior config path is empty; using defaults.");
			return new CampusBehaviorConfig();
		}

		var resolvedPath = path.StartsWith("res://") || path.StartsWith("user://")
			? ProjectSettings.GlobalizePath(path)
			: path;

		if (!File.Exists(resolvedPath))
		{
			GD.PushWarning($"Campus behavior config not found at {resolvedPath}; using defaults.");
			return new CampusBehaviorConfig();
		}

		var json = File.ReadAllText(resolvedPath);
		if (string.IsNullOrWhiteSpace(json))
		{
			GD.PushWarning($"Campus behavior config is empty at {resolvedPath}; using defaults.");
			return new CampusBehaviorConfig();
		}

		var options = new JsonSerializerOptions
		{
			PropertyNameCaseInsensitive = true
		};
		options.Converters.Add(new JsonStringEnumConverter());

		try
		{
			var config = JsonSerializer.Deserialize<CampusBehaviorConfig>(json, options);
			return config ?? new CampusBehaviorConfig();
		}
		catch (Exception ex)
		{
			GD.PushWarning($"Failed to parse campus behavior config: {ex.Message}");
			return new CampusBehaviorConfig();
		}
	}
}

/// <summary>
/// 简单的位置注册表，将逻辑位置 ID 映射到场景位置。
/// 保持行为系统独立于场景树细节。
/// </summary>
public sealed class CampusLocationRegistry
{
	private readonly Dictionary<CampusLocationId, Vector2> _locations = new();

	public void Register(CampusLocationId id, Vector2 position)
	{
		if (id == CampusLocationId.None) return;
		_locations[id] = position;
	}

	public bool TryGetPosition(CampusLocationId id, out Vector2 position)
	{
		return _locations.TryGetValue(id, out position);
	}
}

/// <summary>
/// 跟踪每个位置的当前占用情况，以便像社交恐惧症这样的特质可以根据人群规模做出反应，
/// 而无需硬编码场景知识。
/// </summary>
public sealed class CampusBehaviorWorld
{
	private readonly Dictionary<CampusLocationId, int> _occupancy = new();

	public void Clear()
	{
		_occupancy.Clear();
	}

	public void AddOccupant(CampusLocationId id)
	{
		if (id == CampusLocationId.None || id == CampusLocationId.RandomWander) return;
		if (!_occupancy.ContainsKey(id))
		{
			_occupancy[id] = 0;
		}

		_occupancy[id] += 1;
	}

	public int GetOccupancy(CampusLocationId id)
	{
		return _occupancy.TryGetValue(id, out var count) ? count : 0;
	}
}

/// <summary>
/// 校园演示的轻量级任务容器；它只跟踪剩余工作量。
/// </summary>
public sealed class CampusTask
{
	public CampusTaskType Type { get; }
	public float RemainingSeconds { get; private set; }

	public CampusTask(CampusTaskType type, float remainingSeconds)
	{
		Type = type;
		RemainingSeconds = Mathf.Max(0f, remainingSeconds);
	}

	public void Advance(float delta)
	{
		RemainingSeconds = Mathf.Max(0f, RemainingSeconds - delta);
	}

	public bool IsComplete => RemainingSeconds <= 0f;
}

/// <summary>
/// 自定义需求，尚未成为核心 UnitModel 的一部分（饥饿/社交/精力）。
/// 使用 PropertyValue 以便接入现有的数值系统。
/// </summary>
public sealed class CampusAgentNeeds
{
	public PropertyValue Hunger { get; }
	public PropertyValue Energy { get; }
	public PropertyValue Social { get; }
	public PropertyValue Health { get; }

	public CampusAgentNeeds(float hunger, float energy, float social, float health)
	{
		Hunger = new PropertyValue(hunger);
		Energy = new PropertyValue(energy);
		Social = new PropertyValue(social);
		Health = new PropertyValue(health);
	}
}