using System.Collections.Concurrent;

namespace AgriculturalPlatform.Api.Services;

/// <summary>手机传图上传会话（内存存储，10 分钟过期）</summary>
public sealed class MobileUploadSession
{
    public string Code { get; init; } = string.Empty;
    public DateTime CreatedAt { get; init; } = DateTime.Now;
    public StoredFile? Front { get; set; }
    public StoredFile? Back { get; set; }
    public IdCardOcrResult? FrontOcr { get; set; }
    public IdCardOcrResult? BackOcr { get; set; }
    public bool Done { get; set; }
}

/// <summary>手机传图上传会话存储（单机内存版，后续可换 Redis）</summary>
public sealed class MobileUploadSessionStore
{
    private static readonly TimeSpan Expire = TimeSpan.FromMinutes(10);
    private readonly ConcurrentDictionary<string, MobileUploadSession> _sessions = new();

    public string Create()
    {
        Cleanup();
        var code = Guid.NewGuid().ToString("N")[..8].ToUpperInvariant();
        _sessions[code] = new MobileUploadSession { Code = code };
        return code;
    }

    public MobileUploadSession? Get(string code)
    {
        if (string.IsNullOrWhiteSpace(code)) return null;
        return _sessions.TryGetValue(code.Trim().ToUpperInvariant(), out var s) ? s : null;
    }

    public void Remove(string code) => _sessions.TryRemove(code, out _);

    private void Cleanup()
    {
        var now = DateTime.Now;
        foreach (var kv in _sessions)
        {
            if (now - kv.Value.CreatedAt > Expire) _sessions.TryRemove(kv.Key, out _);
        }
    }
}