using System;
using System.IO;
using System.Linq;
using System.Text.Json;
using Notify.Models;
using Notify.Serialization;

namespace Notify.Services;

/// <summary>
/// 每会话状态文件的读写，位于 %TEMP%\claude-notify-{session_id}.json
/// </summary>
public static class StateStore
{
    private static string FilePath(string sessionId) =>
        Path.Combine(Path.GetTempPath(), $"claude-notify-{Sanitize(sessionId)}.json");

    public static void Save(string sessionId, StateData data)
    {
        try
        {
            File.WriteAllText(FilePath(sessionId), JsonSerializer.Serialize(data, AppJsonContext.Default.StateData));
        }
        catch
        {
            // 落盘失败不致命
        }
    }

    public static StateData? Load(string sessionId)
    {
        try
        {
            var path = FilePath(sessionId);
            if (File.Exists(path))
            {
                return JsonSerializer.Deserialize(File.ReadAllText(path), AppJsonContext.Default.StateData);
            }
        }
        catch
        {
            // 损坏或不可读则当作无状态
        }

        return null;
    }

    public static void Delete(string sessionId)
    {
        try
        {
            var path = FilePath(sessionId);
            if (File.Exists(path))
            {
                File.Delete(path);
            }
        }
        catch
        {
            // 忽略
        }
    }

    // 只保留文件名安全字符，避免 session_id 含特殊字符破坏路径
    private static string Sanitize(string s) =>
        new(s.Where(c => char.IsLetterOrDigit(c) || c is '-' or '_').ToArray());
}