using NetCorePal.Extensions.Domain;

namespace Fengling.RiskControl.Domain.Aggregates.RiskScores;

public class RiskScore : Entity<long>, IAggregateRoot
{
    public long MemberId { get; private set; }
    public string EntityType { get; private set; } = string.Empty;
    public string EntityId { get; private set; } = string.Empty;
    public int TotalScore { get; private set; }
    public RiskLevel RiskLevel { get; private set; }
    private readonly List<RiskFactor> _factors = new();
    public IReadOnlyCollection<RiskFactor> Factors => _factors.AsReadOnly();
    public DateTime CreatedAt { get; private set; } = DateTime.UtcNow;
    public DateTime? ExpiresAt { get; private set; }

    private RiskScore() { }

    public static RiskScore Create(long memberId, string entityType, string entityId, 
        DateTime? expiresAt = null)
    {
        return new RiskScore
        {
            MemberId = memberId,
            EntityType = entityType,
            EntityId = entityId,
            TotalScore = 0,
            RiskLevel = RiskLevel.Low,
            ExpiresAt = expiresAt
        };
    }

    public void AddRiskFactor(string factorType, int points, string description)
    {
        _factors.Add(RiskFactor.Create(factorType, points, description));
        RecalculateScore();
    }

    public void Reset()
    {
        _factors.Clear();
        TotalScore = 0;
        RiskLevel = RiskLevel.Low;
    }

    private static readonly int HIGH_THRESHOLD = 70;
    private static readonly int MEDIUM_THRESHOLD = 30;

    private void RecalculateScore()
    {
        TotalScore = _factors.Sum(f => f.Points);
        RiskLevel = TotalScore >= HIGH_THRESHOLD ? RiskLevel.High :
                   TotalScore >= MEDIUM_THRESHOLD ? RiskLevel.Medium :
                   RiskLevel.Low;
    }

    public bool IsExpired()
    {
        return ExpiresAt.HasValue && DateTime.UtcNow > ExpiresAt.Value;
    }
}