using Application.Abstractions.Data;
using Domain.Entities.Donations.ValueObject;
using Web.Api.Common;
using Microsoft.EntityFrameworkCore;

namespace Web.Api.Endpoints.Widget;

/// <summary>WidgetToken + configID 기반 후원 순위 (위젯 초기 로드용, 인증 불필요).
/// configID 지정 시 해당 RankConfig의 Period + MaxRankCount 적용. 미지정 시 활성 첫 번째 또는 Daily/Top5 default.
/// Donation 테이블 실시간 GROUP BY (DonationRanking 사전 집계 무시).</summary>
internal sealed class DonationRankingByToken : IEndpoint
{
    public void MapEndpoint(IEndpointRouteBuilder app)
    {
        app.MapGet("api/widget/rank/by-token/{widgetToken}", async (
            string widgetToken,
            int? configID,
            IAppDbContext db,
            CancellationToken ct
        ) => {
            var channelID = await db.Channel.AsNoTracking()
                .Where(c => c.WidgetToken == widgetToken && c.IsActive)
                .Select(c => c.ID)
                .FirstOrDefaultAsync(ct);

            if (channelID == 0)
            {
                return ApiResponse.Ok(new { list = Array.Empty<object>() });
            }

            // RankConfig 조회 (configID 지정 또는 활성 첫 번째)
            var rankCfgQuery = db.DonationRankConfig.AsNoTracking()
                .Where(r => r.ChannelID == channelID);

            if (configID.HasValue)
            {
                rankCfgQuery = rankCfgQuery.Where(r => r.ID == configID.Value);
            }
            else
            {
                rankCfgQuery = rankCfgQuery.Where(r => r.IsActive);
            }

            var rankCfg = await rankCfgQuery
                .OrderByDescending(r => r.ID)
                .Select(r => new { r.Period, r.MaxRankCount, r.StartAt, r.EndAt })
                .FirstOrDefaultAsync(ct);

            // config 없으면 default (Daily, Top5)
            var period = rankCfg?.Period ?? RankPeriodType.Daily;
            var limit = rankCfg?.MaxRankCount ?? 5;

            // Period에 따른 시작 시각
            var now = DateTime.UtcNow;
            DateTime? rangeStart = period switch
            {
                RankPeriodType.Daily => now.Date,
                RankPeriodType.Weekly => now.Date.AddDays(-(int)now.DayOfWeek),
                RankPeriodType.Monthly => new DateTime(now.Year, now.Month, 1, 0, 0, 0, DateTimeKind.Utc),
                _ => null  // Total 등
            };

            // 추가 StartAt/EndAt 필터 (config가 명시한 기간)
            var startAt = rankCfg?.StartAt ?? rangeStart;
            var endAt = rankCfg?.EndAt;

            var donationQuery = db.Donation.AsNoTracking()
                .Where(d => d.ChannelID == channelID && !d.IsTest);

            if (startAt.HasValue)
            {
                donationQuery = donationQuery.Where(d => d.CreatedAt >= startAt.Value);
            }
            if (endAt.HasValue)
            {
                donationQuery = donationQuery.Where(d => d.CreatedAt <= endAt.Value);
            }

            // SponsorMemberID로 통합 (같은 sponsor가 다른 별명으로 후원해도 합산). SendName은 가장 최근 것.
            var raw = await donationQuery
                .GroupBy(d => d.SponsorMemberID)
                .Select(g => new
                {
                    SponsorMemberID = g.Key,
                    SendName = g.OrderByDescending(d => d.CreatedAt).Select(d => d.SendName).FirstOrDefault() ?? "",
                    TotalAmount = g.Sum(d => d.NetAmount),
                    DonationCount = g.Count()
                })
                .OrderByDescending(g => g.TotalAmount)
                .Take(limit)
                .ToListAsync(ct);

            var list = raw.Select((r, i) => new
            {
                rank = i + 1,
                sponsorMemberID = r.SponsorMemberID,
                sponsorName = r.SendName,
                totalAmount = r.TotalAmount,
                donationCount = r.DonationCount
            }).ToList();

            return ApiResponse.Ok(new { list });
        })
        .WithTags("Widget")
        .AllowAnonymous();
    }
}