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

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

        return _actionLookup.GetValueOrDefault(id);
    }

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

    public CampusTaskType Type { get; }
    public float RemainingSeconds { get; private set; }

    public bool IsComplete => RemainingSeconds <= 0f;

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

/// <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 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);
    }

    public PropertyValue Hunger { get; }
    public PropertyValue Energy { get; }
    public PropertyValue Social { get; }
    public PropertyValue Health { get; }
}