using System.ComponentModel.DataAnnotations;
using System.ComponentModel.DataAnnotations.Schema;

namespace Domain.Entities.Members;

/// <summary>
/// 채널별 누적 방송 지표 (매일 자정 재계산)
/// </summary>
public sealed class ChannelBroadcastStats
{
    [ForeignKey(nameof(ChannelID))]
    public Channel Channel { get; private set; } = null!;

    [Key]
    public int ChannelID { get; private set; }

    public long TotalDurationSec { get; private set; }

    public long CumulativeViews { get; private set; }

    public long TotalLikes { get; private set; }

    public int SessionCount { get; private set; }

    public DateTime? LastBroadcastAt { get; private set; }

    public DateTime? LastAggregatedAt { get; private set; }

    public DateTime CreatedAt { get; private set; } = DateTime.UtcNow;

    private ChannelBroadcastStats() { }

    private ChannelBroadcastStats(int channelID)
    {
        if (channelID <= 0)
        {
            throw new ArgumentOutOfRangeException(nameof(channelID));
        }

        ChannelID = channelID;
    }

    public static ChannelBroadcastStats Create(int channelID)
    {
        return new(channelID);
    }

    public void Update(long totalDurationSec, long cumulativeViews, long totalLikes, int sessionCount, DateTime? lastBroadcastAt)
    {
        TotalDurationSec = totalDurationSec;
        CumulativeViews = cumulativeViews;
        TotalLikes = totalLikes;
        SessionCount = sessionCount;
        LastBroadcastAt = lastBroadcastAt;
        LastAggregatedAt = DateTime.UtcNow;
    }
}