using ModelContextProtocol;
using ModelContextProtocol.Server;
using System.ComponentModel;
using System.Text.Json;
using System.Text.Json.Serialization;

namespace AspNetCoreMcpServer.Tools;

[McpServerToolType]
public sealed class WeatherTools
{
    private readonly IHttpClientFactory _httpClientFactory;
    private const string WeatherApiUrl = "http://10.1.57.124:8002/ledclock/weather.txt";

    public WeatherTools(IHttpClientFactory httpClientFactory)
    {
        _httpClientFactory = httpClientFactory;
    }

    [McpServerTool, Description("获取今天的天气信息")]
    [McpMeta("category", "weather")]
    [McpMeta("dataSource", "local")]
    public async Task<string> GetTodayWeather()
    {
        try
        {
            var weatherData = await FetchWeatherDataAsync();
            
            if (weatherData?.Data == null || weatherData.Data.Count == 0)
            {
                return "无法获取天气数据";
            }

            // 获取今天的日期
            var today = DateTime.Now.ToString("yyyy-MM-dd");
            
            // 查找今天的天气数据
            var todayWeather = weatherData.Data.FirstOrDefault(d => d.Date == today);
            
            if (todayWeather == null)
            {
                // 如果没有今天的数据，返回第一天的数据
                todayWeather = weatherData.Data.First();
                return $"""
                        今天天气信息 (数据日期: {todayWeather.Date})
                        地区: {weatherData.Province}/{weatherData.City}
                        天气: {todayWeather.WeatherDescription}
                        温度: {todayWeather.MinTemperature}°C ~ {todayWeather.MaxTemperature}°C
                        风向风力: {todayWeather.WindDescription}
                        
                        注意: 未找到今日准确数据，显示的是最近日期的天气信息。
                        """;
            }

            return $"""
                    今天天气信息
                    地区: {weatherData.Province}/{weatherData.City}
                    日期: {todayWeather.Date}
                    天气: {todayWeather.WeatherDescription}
                    温度: {todayWeather.MinTemperature}°C ~ {todayWeather.MaxTemperature}°C
                    风向风力: {todayWeather.WindDescription}
                    
                    {GetWeatherAdvice(todayWeather)}
                    """;
        }
        catch (HttpRequestException ex)
        {
            return $"网络请求失败: {ex.Message}";
        }
        catch (JsonException ex)
        {
            return $"数据解析失败: {ex.Message}";
        }
        catch (Exception ex)
        {
            return $"获取天气信息时发生错误: {ex.Message}";
        }
    }

    [McpServerTool, Description("获取未来几天的天气预报")]
    [McpMeta("category", "weather")]
    [McpMeta("dataSource", "local")]
    public async Task<string> GetWeatherForecast(
        [Description("预报天数，默认为3天，最多15天")] int days = 3)
    {
        try
        {
            if (days < 1 || days > 15)
            {
                return "预报天数必须在1-15天之间";
            }

            var weatherData = await FetchWeatherDataAsync();
            
            if (weatherData?.Data == null || weatherData.Data.Count == 0)
            {
                return "无法获取天气数据";
            }

            var forecasts = weatherData.Data.Take(days).Select((weather, index) =>
            {
                var dateLabel = index == 0 ? "今天" : index == 1 ? "明天" : index == 2 ? "后天" : weather.Date;
                return $"""
                        {dateLabel} ({weather.Date})
                        天气: {weather.WeatherDescription}
                        温度: {weather.MinTemperature}°C ~ {weather.MaxTemperature}°C
                        风向风力: {weather.WindDescription}
                        """;
            });

            return $"""
                    {weatherData.Province}/{weatherData.City} 未来{days}天天气预报
                    
                    {string.Join("\n---\n", forecasts)}
                    """;
        }
        catch (Exception ex)
        {
            return $"获取天气预报时发生错误: {ex.Message}";
        }
    }

    [McpServerTool, Description("获取指定日期的天气信息")]
    [McpMeta("category", "weather")]
    [McpMeta("dataSource", "local")]
    public async Task<string> GetWeatherByDate(
        [Description("日期，格式: yyyy-MM-dd，例如: 2025-11-15")] string date)
    {
        try
        {
            // 验证日期格式
            if (!DateTime.TryParseExact(date, "yyyy-MM-dd", null, 
                System.Globalization.DateTimeStyles.None, out var parsedDate))
            {
                return "日期格式错误，请使用 yyyy-MM-dd 格式，例如: 2025-11-15";
            }

            var weatherData = await FetchWeatherDataAsync();
            
            if (weatherData?.Data == null || weatherData.Data.Count == 0)
            {
                return "无法获取天气数据";
            }

            var targetWeather = weatherData.Data.FirstOrDefault(d => d.Date == date);
            
            if (targetWeather == null)
            {
                var availableDates = string.Join(", ", weatherData.Data.Select(d => d.Date).Take(5));
                return $"未找到日期 {date} 的天气数据\n\n可用的日期: {availableDates}...";
            }

            var daysFromNow = (parsedDate - DateTime.Now).Days;
            var dateLabel = daysFromNow switch
            {
                0 => "今天",
                1 => "明天",
                2 => "后天",
                _ => daysFromNow > 0 ? $"{daysFromNow}天后" : $"{-daysFromNow}天前"
            };

            return $"""
                    {dateLabel}的天气信息
                    地区: {weatherData.Province}/{weatherData.City}
                    日期: {targetWeather.Date}
                    天气: {targetWeather.WeatherDescription}
                    温度: {targetWeather.MinTemperature}°C ~ {targetWeather.MaxTemperature}°C
                    风向风力: {targetWeather.WindDescription}
                    
                    {GetWeatherAdvice(targetWeather)}
                    """;
        }
        catch (Exception ex)
        {
            return $"获取天气信息时发生错误: {ex.Message}";
        }
    }

    [McpServerTool, Description("获取完整的天气数据概览")]
    [McpMeta("category", "weather")]
    [McpMeta("dataSource", "local")]
    public async Task<string> GetWeatherOverview()
    {
        try
        {
            var weatherData = await FetchWeatherDataAsync();
            
            if (weatherData?.Data == null || weatherData.Data.Count == 0)
            {
                return "无法获取天气数据";
            }

            // 统计信息
            var totalDays = weatherData.Data.Count;
            var avgMaxTemp = weatherData.Data.Average(d => int.Parse(d.MaxTemperature));
            var avgMinTemp = weatherData.Data.Average(d => int.Parse(d.MinTemperature));
            var rainyDays = weatherData.Data.Count(d => d.WeatherDescription.Contains("雨"));
            var sunnyDays = weatherData.Data.Count(d => d.WeatherDescription.Contains("晴"));

            // 今天的天气
            var today = DateTime.Now.ToString("yyyy-MM-dd");
            var todayWeather = weatherData.Data.FirstOrDefault(d => d.Date == today) 
                               ?? weatherData.Data.First();

            return $"""
                    天气数据概览
                    地区: {weatherData.Province}/{weatherData.City}
                    数据范围: {weatherData.Data.First().Date} 至 {weatherData.Data.Last().Date}
                    
                    今日天气:
                    {todayWeather.WeatherDescription} | {todayWeather.MinTemperature}°C ~ {todayWeather.MaxTemperature}°C | {todayWeather.WindDescription}
                    
                    统计信息 (未来{totalDays}天):
                    - 平均最高温度: {avgMaxTemp:F1}°C
                    - 平均最低温度: {avgMinTemp:F1}°C
                    - 晴天: {sunnyDays}天
                    - 雨天: {rainyDays}天
                    
                    温馨提示: {GetOverviewAdvice(weatherData.Data)}
                    """;
        }
        catch (Exception ex)
        {
            return $"获取天气概览时发生错误: {ex.Message}";
        }
    }

    // ==================== 私有辅助方法 ====================

    private async Task<WeatherResponse?> FetchWeatherDataAsync()
    {
        var client = _httpClientFactory.CreateClient();
        client.Timeout = TimeSpan.FromSeconds(10);

        using var response = await client.GetAsync(WeatherApiUrl);
        response.EnsureSuccessStatusCode();

        var content = await response.Content.ReadAsStringAsync();
        
        var options = new JsonSerializerOptions
        {
            PropertyNameCaseInsensitive = true
        };
        
        return JsonSerializer.Deserialize<WeatherResponse>(content, options);
    }

    private static string GetWeatherAdvice(WeatherData weather)
    {
        var advice = new List<string>();

        // 根据天气状况给建议
        if (weather.WeatherDescription.Contains("雨"))
        {
            advice.Add("☔ 记得带伞");
        }
        else if (weather.WeatherDescription.Contains("晴"))
        {
            advice.Add("☀️ 天气晴朗，适合外出");
        }
        else if (weather.WeatherDescription.Contains("多云"))
        {
            advice.Add("⛅ 天气多云，可以外出活动");
        }

        // 根据温度给建议
        var maxTemp = int.Parse(weather.MaxTemperature);
        var minTemp = int.Parse(weather.MinTemperature);
        var tempDiff = maxTemp - minTemp;

        if (maxTemp > 30)
        {
            advice.Add("🌡️ 高温天气，注意防暑降温");
        }
        else if (minTemp < 10)
        {
            advice.Add("🧥 气温较低，注意保暖");
        }

        if (tempDiff > 10)
        {
            advice.Add("👔 昼夜温差大，适当增减衣物");
        }

        return advice.Count > 0 ? $"温馨提示: {string.Join("；", advice)}" : "";
    }

    private static string GetOverviewAdvice(List<WeatherData> weatherList)
    {
        var adviceList = new List<string>();

        // 检查是否有连续雨天
        var consecutiveRainyDays = 0;
        var maxConsecutiveRainy = 0;
        foreach (var weather in weatherList)
        {
            if (weather.WeatherDescription.Contains("雨"))
            {
                consecutiveRainyDays++;
                maxConsecutiveRainy = Math.Max(maxConsecutiveRainy, consecutiveRainyDays);
            }
            else
            {
                consecutiveRainyDays = 0;
            }
        }

        if (maxConsecutiveRainy >= 3)
        {
            adviceList.Add($"未来有连续{maxConsecutiveRainy}天降雨，注意出行安全");
        }

        // 检查温度变化
        var firstTemp = int.Parse(weatherList.First().MaxTemperature);
        var lastTemp = int.Parse(weatherList.Last().MaxTemperature);
        var tempChange = lastTemp - firstTemp;

        if (Math.Abs(tempChange) > 5)
        {
            adviceList.Add(tempChange > 0 ? "未来气温逐渐上升" : "未来气温逐渐下降");
        }

        return adviceList.Count > 0 ? string.Join("；", adviceList) : "天气状况平稳";
    }
}

// ==================== 数据模型 ====================

internal class WeatherResponse
{
    [JsonPropertyName("code")]
    public int Code { get; set; }

    [JsonPropertyName("message")]
    public string Message { get; set; } = "";

    [JsonPropertyName("province")]
    public string Province { get; set; } = "";

    [JsonPropertyName("city")]
    public string City { get; set; } = "";

    [JsonPropertyName("data")]
    public List<WeatherData> Data { get; set; } = new();
}

internal class WeatherData
{
    [JsonPropertyName("date")]
    public string Date { get; set; } = "";

    [JsonPropertyName("weatherDescription")]
    public string WeatherDescription { get; set; } = "";

    [JsonPropertyName("maxTemperature")]
    public string MaxTemperature { get; set; } = "";

    [JsonPropertyName("minTemperature")]
    public string MinTemperature { get; set; } = "";

    [JsonPropertyName("wea_img")]
    public string WeaImg { get; set; } = "";

    [JsonPropertyName("windDescription")]
    public string WindDescription { get; set; } = "";
}