using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.Text;
using Domain.Entities.Store.ValueObject;
using Application.Abstractions.Messaging;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Mvc.RazorPages;

namespace Admin.Pages.Store.Settlement;

/// <summary>
/// 게임사 정산 목록 CSV 다운로드. 현재 필터 기준 최대 10,000 row 익스포트.
/// </summary>
public class ExportModel(IMediator mediator) : PageModel
{
    [BindProperty(SupportsGet = true)]
    public QueryParams Query { get; set; } = new();

    public sealed class QueryParams
    {
        [DisplayName("게임")]
        public int? GameID { get; set; }

        [DisplayName("연도")]
        [Range(2000, 9999)]
        public int? Year { get; set; }

        [DisplayName("월")]
        [Range(1, 12)]
        public int? Month { get; set; }

        [DisplayName("정산 상태")]
        public GameSettlementStatus? Status { get; set; }
    }

    public async Task<IActionResult> OnGetAsync(CancellationToken ct)
    {
        // 한 번에 최대 10,000 row 익스포트 (운영상 충분)
        var result = await mediator.Send(new SearchGameSettlements.Query(
            Query.GameID,
            Query.Year,
            Query.Month,
            Query.Status,
            1,
            10000
        ), ct);

        var sb = new StringBuilder();
        sb.Append(''); // UTF-8 BOM (Excel 한글 호환)
        sb.AppendLine("게임ID,게임명,게임사,연도,월,매출(원),주문수,상태,등록일시,처리일시,처리관리자,관리자메모");

        foreach (var c in result.List)
        {
            sb.Append(c.GameID).Append(',');
            sb.Append(Csv(c.GameName)).Append(',');
            sb.Append(Csv(c.GamePublisher)).Append(',');
            sb.Append(c.Year).Append(',');
            sb.Append(c.Month).Append(',');
            sb.Append(c.TotalRevenueAmount).Append(',');
            sb.Append(c.OrderCount).Append(',');
            sb.Append(Csv(StatusToText(c.Status))).Append(',');
            sb.Append(c.CreatedAt.ToString("yyyy-MM-dd HH:mm")).Append(',');
            sb.Append(c.SettledAt?.ToString("yyyy-MM-dd HH:mm") ?? "").Append(',');
            sb.Append(Csv(c.SettledByAdminEmail ?? "")).Append(',');
            sb.AppendLine(Csv(c.AdminMemo ?? ""));
        }

        var fileName = $"GameSettlements_{DateTime.UtcNow:yyyyMMdd_HHmmss}.csv";
        return File(Encoding.UTF8.GetBytes(sb.ToString()), "text/csv", fileName);
    }

    private static string Csv(string s)
    {
        if (string.IsNullOrEmpty(s))
        {
            return "";
        }

        if (s.Contains(',') || s.Contains('"') || s.Contains('\n') || s.Contains('\r'))
        {
            return "\"" + s.Replace("\"", "\"\"") + "\"";
        }

        return s;
    }

    private static string StatusToText(GameSettlementStatus s) => s switch
    {
        GameSettlementStatus.Pending => "정산 대기",
        GameSettlementStatus.Settled => "정산 완료",
        _ => "?"
    };
}