using System.Threading.Channels;
using BMA.EHR.Recruit.Core;
using BMA.EHR.Recruit.Services;
using Microsoft.AspNetCore.Http;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Logging;
using OfficeOpenXml;
using System.Net.Http.Headers;
using BMA.EHR.Recruit.Data;
using EFCore.BulkExtensions;
using BMA.EHR.Recruit.Extensions;
using BMA.EHR.Recruit.Models.Recruits;
using BMA.EHR.Recruit.Requests.Recruits;

namespace BMA.EHR.Recruit.Services;

public class ImportBackgroundService : BackgroundService
{
    private readonly ImportJobQueue _queue;
    private readonly ImportJobTracker _tracker;
    private readonly IServiceScopeFactory _scopeFactory;
    private readonly ILogger<ImportBackgroundService> _logger;

    public ImportBackgroundService(
        ImportJobQueue queue,
        ImportJobTracker tracker,
        IServiceScopeFactory scopeFactory,
        ILogger<ImportBackgroundService> logger)
    {
        _queue = queue;
        _tracker = tracker;
        _scopeFactory = scopeFactory;
        _logger = logger;
    }

    protected override async Task ExecuteAsync(CancellationToken stoppingToken)
    {
        _logger.LogInformation("ImportBackgroundService started.");

        while (!stoppingToken.IsCancellationRequested)
        {
            var job = await _queue.DequeueAsync(stoppingToken);

            _ = Task.Run(async () =>
            {
                using var scope = _scopeFactory.CreateScope();
                var context = scope.ServiceProvider.GetRequiredService<ApplicationDbContext>();
                var minioService = scope.ServiceProvider.GetRequiredService<MinIOService>();
                var recruitService = scope.ServiceProvider.GetRequiredService<RecruitService>();
                var webHostEnv = scope.ServiceProvider.GetRequiredService<IWebHostEnvironment>();
                var logger = scope.ServiceProvider.GetRequiredService<ILogger<ImportBackgroundService>>();

                try
                {
                    _tracker.UpdateStatus(job.JobId, ImportJobStatus.Running);

                    switch (job.JobType)
                    {
                        case ImportJobType.CandidateFile:
                            await ProcessCandidateFileAsync(context, minioService, webHostEnv, job);
                            break;
                        case ImportJobType.CandidateFileById:
                            await ProcessCandidateFileByIdAsync(context, minioService, recruitService, webHostEnv, job);
                            break;
                        case ImportJobType.ScoreFile:
                            await ProcessScoreFileAsync(context, minioService, recruitService, job);
                            break;
                        case ImportJobType.ResultFile:
                            await ProcessResultFileAsync(context, recruitService, job);
                            break;
                    }

                    _tracker.UpdateStatus(job.JobId, ImportJobStatus.Completed, job.TotalCount);
                }
                catch (Exception ex)
                {
                    logger.LogError(ex, "Import job {JobId} failed: {Message}", job.JobId, ex.Message);
                    _tracker.UpdateStatus(job.JobId, ImportJobStatus.Failed, 0, ex.InnerException?.Message ?? ex.Message);

                    // cleanup minio file on failure
                    if (!string.IsNullOrEmpty(job.ImportDocId))
                    {
                        try { await minioService.DeleteFileAsync(Guid.Parse(job.ImportDocId)); } catch { }
                    }
                }
                finally
                {
                    // cleanup temp file
                    try
                    {
                        if (System.IO.File.Exists(job.ImportFile))
                            System.IO.File.Delete(job.ImportFile);
                    }
                    catch { }
                }
            }, stoppingToken);
        }
    }

    #region CandidateFile

    private async Task ProcessCandidateFileAsync(ApplicationDbContext _context, MinIOService _minioService, IWebHostEnvironment _webHostEnv, ImportJobInfo job)
    {
        var imported = await _context.RecruitImports.FindAsync(job.RecruitImportId);
        if (imported == null) throw new Exception("RecruitImport not found");

        using var c_package = new ExcelPackage(new FileInfo(job.ImportFile));
        for (int i = 0; i < c_package.Workbook.Worksheets.Count; i++)
        {
            var workSheet = c_package.Workbook.Worksheets[i];
            var totalRows = workSheet.Dimension.Rows;
            var cols = workSheet.GetHeaderColumns();

            int row = 2;
            int batchCount = 0;
            const int batchSize = 500;
            int totalProcessed = 0;

            var batchRecruits = new List<Models.Recruits.Recruit>();
            var batchEducations = new List<RecruitEducation>();
            var batchOccupations = new List<RecruitOccupation>();
            var batchAddresses = new List<RecruitAddress>();
            var batchPayments = new List<RecruitPayment>();
            var batchCertificates = new List<RecruitCertificate>();

            while (row <= totalRows)
            {
                var cell1 = workSheet?.Cells[row, 1]?.GetValue<string>();
                if (cell1 == "" || cell1 == null) break;

                var r = new Models.Recruits.Recruit();
                r.ExamId = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.ExamID)]?.GetValue<string>();
                r.CitizenId = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.PersonalID)]?.GetValue<string>();
                r.Prefix = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Prefix)]?.GetValue<string>();
                r.FirstName = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.FirstName)]?.GetValue<string>();
                r.LastName = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.LastName)]?.GetValue<string>();
                r.Gendor = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Gender)]?.GetValue<string>();
                r.National = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.National)]?.GetValue<string>().IsNull("");
                r.Race = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Race)]?.GetValue<string>().IsNull("");
                r.Religion = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Religion)]?.GetValue<string>().IsNull("");
                r.DateOfBirth = Convert.ToDateTime(workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.DateOfBirth)]?.GetValue<string>().ToDateTime(DateTimeFormat.Ymd, "-"));
                r.Marry = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Marry)]?.GetValue<string>();
                r.Isspecial = "N";
                r.CitizenCardIssuer = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.PersonalCardIssue)]?.GetValue<string>();
                r.CitizenCardExpireDate = Convert.ToDateTime(workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.PersonalCardExpireDate)]?.GetValue<string>().ToDateTime(DateTimeFormat.Ymd, "-"));
                r.ApplyDate = (DateTime)workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.ApplyDate)]?.GetValue<DateTime>();
                r.PositionName = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.PositionName)]?.GetValue<string>().IsNull("");
                r.PositionType = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.PositionType)]?.GetValue<string>().IsNull("");
                r.PositionLevel = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.PositionLevel)]?.GetValue<string>().IsNull("");

                // address
                var address = new RecruitAddress()
                {
                    Address = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Address)]?.GetValue<string>() ?? "",
                    Moo = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Moo)]?.GetValue<string>() ?? "",
                    Soi = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Soi)]?.GetValue<string>() ?? "",
                    Road = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Road)]?.GetValue<string>() ?? "",
                    District = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.District)]?.GetValue<string>() ?? "",
                    Amphur = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Amphur)]?.GetValue<string>() ?? "",
                    Province = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Province)]?.GetValue<string>() ?? "",
                    ZipCode = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.ZipCode)]?.GetValue<string>() ?? "",
                    Telephone = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Telephone)]?.GetValue<string>() ?? "",
                    Mobile = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Mobile)]?.GetValue<string>() ?? "",
                    Address1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Address1)]?.GetValue<string>() ?? "",
                    Moo1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Moo1)]?.GetValue<string>() ?? "",
                    Soi1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Soi1)]?.GetValue<string>() ?? "",
                    Road1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Road1)]?.GetValue<string>() ?? "",
                    District1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.District1)]?.GetValue<string>() ?? "",
                    Amphur1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Amphur1)]?.GetValue<string>() ?? "",
                    Province1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Province1)]?.GetValue<string>() ?? "",
                    ZipCode1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.ZipCode1)]?.GetValue<string>() ?? "",
                };

                // payment
                var payment = new RecruitPayment()
                {
                    PaymentId = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.PaymentID)]?.GetValue<string>() ?? "",
                    CompanyCode = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.CompanyCode)]?.GetValue<string>() ?? "",
                    TextFile = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.TextFile)]?.GetValue<string>() ?? "",
                    BankCode = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.BankCode)]?.GetValue<string>() ?? "",
                    AccountNumber = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.AccouontNumer)]?.GetValue<string>() ?? "",
                    TransDate = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.TransDate)]?.GetValue<string>() ?? "",
                    TransTime = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.TransTime)]?.GetValue<string>() ?? "",
                    CustomerName = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.CustomerName)]?.GetValue<string>() ?? "",
                    RefNo1 = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.RefNo1)]?.GetValue<string>() ?? "",
                    TermBranch = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.TermBranch)]?.GetValue<string>() ?? "",
                    TellerId = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.TellerID)]?.GetValue<string>() ?? "",
                    CreditDebit = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.CreditDebit)]?.GetValue<string>() ?? "",
                    PaymentType = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Type)]?.GetValue<string>(),
                    ChequeNo = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.ChequeNo)]?.GetValue<string>() ?? "",
                    Amount = (decimal)workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Amount)]?.GetValue<decimal>(),
                    ChqueBankCode = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.ChqBankCode)]?.GetValue<string>() ?? ""
                };

                // occupation
                var occupation = new RecruitOccupation()
                {
                    Occupation = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Occupation)]?.GetValue<string>() ?? "",
                    Position = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Position)]?.GetValue<string>() ?? "",
                    Workplace = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Workplace)]?.GetValue<string>() ?? "",
                    Telephone = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.WorkplaceTelephone)]?.GetValue<string>() ?? "",
                    WorkAge = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.WorkAge)]?.GetValue<string>() ?? "",
                };

                // certificate
                var certificate = new RecruitCertificate()
                {
                    CertificateNo = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.CertificateNo)]?.GetValue<string>() ?? "",
                    Description = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.CertificateDesc)]?.GetValue<string>() ?? "",
                    IssueDate = Convert.ToDateTime(workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.CertificateIssueDate)]?.GetValue<string>().ToDateTime(DateTimeFormat.Ymd, "-")),
                    ExpiredDate = Convert.ToDateTime(workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.CertificateExpireDate)]?.GetValue<string>().ToDateTime(DateTimeFormat.Ymd, "-"))
                };

                var education = new RecruitEducation()
                {
                    Degree = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Degree)]?.GetValue<string>() ?? "",
                    Major = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.Major)]?.GetValue<string>() ?? "",
                    MajorGroupId = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.MajorGroupID)]?.GetValue<string>() ?? "",
                    MajorGroupName = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.MajorGroupName)]?.GetValue<string>() ?? "",
                    University = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.University)]?.GetValue<string>() ?? "",
                    GPA = (double)workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.GPA)]?.GetValue<double>(),
                    Specialist = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.SpecialList)]?.GetValue<string>() ?? "",
                    HighDegree = workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.HighDegree)]?.GetValue<string>() ?? "",
                    BachelorDate = Convert.ToDateTime(workSheet?.Cells[row, GetColumnIndex(cols, CandidateFileHeader.BachelorDate)]?.GetValue<string>().ToDateTime(DateTimeFormat.Ymd, "-"))
                };

                r.Addresses.Add(address);
                r.Payments.Add(payment);
                r.Occupations.Add(occupation);
                r.Certificates.Add(certificate);
                r.Educations.Add(education);

                r.RecruitImport = imported;
                batchRecruits.Add(r);
                batchAddresses.Add(address);
                batchPayments.Add(payment);
                batchOccupations.Add(occupation);
                batchCertificates.Add(certificate);
                batchEducations.Add(education);

                row++;
                batchCount++;
                totalProcessed++;

                if (batchCount >= batchSize)
                {
                    await _context.BulkInsertAsync(batchRecruits, options => { options.SetOutputIdentity = true; });

                    for (int j = 0; j < batchRecruits.Count; j++)
                    {
                        batchAddresses[j].Recruit = batchRecruits[j];
                        batchPayments[j].Recruit = batchRecruits[j];
                        batchOccupations[j].Recruit = batchRecruits[j];
                        batchCertificates[j].Recruit = batchRecruits[j];
                        batchEducations[j].Recruit = batchRecruits[j];
                    }

                    await _context.BulkInsertAsync(batchAddresses);
                    await _context.BulkInsertAsync(batchPayments);
                    await _context.BulkInsertAsync(batchOccupations);
                    await _context.BulkInsertAsync(batchCertificates);
                    await _context.BulkInsertAsync(batchEducations);

                    batchRecruits.Clear();
                    batchAddresses.Clear();
                    batchPayments.Clear();
                    batchOccupations.Clear();
                    batchCertificates.Clear();
                    batchEducations.Clear();
                    batchCount = 0;
                    _tracker.UpdateStatus(job.JobId, ImportJobStatus.Running, totalProcessed);
                }
            }

            // Process remaining records
            if (batchRecruits.Count > 0)
            {
                await _context.BulkInsertAsync(batchRecruits, options => { options.SetOutputIdentity = true; });

                for (int j = 0; j < batchRecruits.Count; j++)
                {
                    batchAddresses[j].Recruit = batchRecruits[j];
                    batchPayments[j].Recruit = batchRecruits[j];
                    batchOccupations[j].Recruit = batchRecruits[j];
                    batchCertificates[j].Recruit = batchRecruits[j];
                    batchEducations[j].Recruit = batchRecruits[j];
                }

                await _context.BulkInsertAsync(batchAddresses);
                await _context.BulkInsertAsync(batchPayments);
                await _context.BulkInsertAsync(batchOccupations);
                await _context.BulkInsertAsync(batchCertificates);
                await _context.BulkInsertAsync(batchEducations);
            }
        }

        job.TotalCount = _tracker.GetJob(job.JobId)?.ProcessedCount ?? 0;
    }

    #endregion

    #region CandidateFileById

    private async Task ProcessCandidateFileByIdAsync(ApplicationDbContext _context, MinIOService _minioService, RecruitService _recruitService, IWebHostEnvironment _webHostEnv, ImportJobInfo job)
    {
        var imported = await _context.RecruitImports.FindAsync(job.RecruitImportId);
        if (imported == null) throw new Exception("RecruitImport not found");

        // Save import history using regular SaveChanges (small operation)
        imported.ImportHostories.Add(new RecruitImportHistory
        {
            Description = "นำเข้าข้อมูลผู้สมัครสอบแข่งขัน",
            CreatedAt = DateTime.Now,
            CreatedUserId = job.UserId ?? "",
            CreatedFullName = job.FullName ?? "System Administrator",
            LastUpdatedAt = DateTime.Now,
            LastUpdateUserId = job.UserId ?? "",
            LastUpdateFullName = job.FullName ?? "System Administrator",
        });
        await _context.SaveChangesAsync();
        _context.ChangeTracker.Clear();

        var importId = imported.Id;

        using var c_package = new ExcelPackage(new FileInfo(job.ImportFile));
        for (int i = 0; i < c_package.Workbook.Worksheets.Count; i++)
        {
            var workSheet = c_package.Workbook.Worksheets[i];
            var totalRows = workSheet.Dimension.Rows;

            int row = 2;
            int batchCount = 0;
            const int batchSize = 500;
            int totalProcessed = 0;

            var batchRecruits = new List<Models.Recruits.Recruit>();
            var batchEducations = new List<RecruitEducation>();
            var batchOccupations = new List<RecruitOccupation>();
            var batchAddresses = new List<RecruitAddress>();
            var batchPayments = new List<RecruitPayment>();

            while (row <= totalRows)
            {
                var cell1 = workSheet?.Cells[row, 1]?.GetValue<string>();
                if (cell1 == "" || cell1 == null) break;

                var r = new Models.Recruits.Recruit();
                r.ExamId = workSheet?.Cells[row, 1]?.GetValue<string>() ?? "";
                r.PositionName = workSheet?.Cells[row, 3]?.GetValue<string>() ?? "";
                r.HddPosition = workSheet?.Cells[row, 4]?.GetValue<string>() ?? "";
                r.Prefix = workSheet?.Cells[row, 5]?.GetValue<string>() == "อื่น ๆ" ? workSheet?.Cells[row, 6]?.GetValue<string>() ?? "" : workSheet?.Cells[row, 5]?.GetValue<string>() ?? "";
                r.FirstName = workSheet?.Cells[row, 7]?.GetValue<string>() ?? "";
                r.LastName = workSheet?.Cells[row, 8]?.GetValue<string>() ?? "";
                r.Gendor = workSheet?.Cells[row, 98]?.GetValue<string>() ?? "";
                r.National = workSheet?.Cells[row, 9]?.GetValue<string>() ?? "";
                r.Race = "";
                r.Religion = workSheet?.Cells[row, 10]?.GetValue<string>() ?? "";
                r.DateOfBirth = !string.IsNullOrWhiteSpace(workSheet?.Cells[row, 11]?.GetValue<string>()) ? _recruitService.CheckDateTime(workSheet?.Cells[row, 11]?.GetValue<string>() ?? "", "dd/MM/yyyy") : null;
                r.CitizenId = workSheet?.Cells[row, 12]?.GetValue<string>() ?? "";
                r.typeTest = workSheet?.Cells[row, 13]?.GetValue<string>() ?? "";
                r.Marry = "";
                r.Isspecial = "N";
                r.CitizenCardExpireDate = null;
                r.ModifiedDate = null;
                r.ApplyDate = !string.IsNullOrWhiteSpace(workSheet?.Cells[row, 87]?.GetValue<string>()) ? _recruitService.CheckDateTime(workSheet?.Cells[row, 87]?.GetValue<string>() ?? "", "dd/MM/yyyy") : null;
                r.PositionType = "";
                r.PositionLevel = "";
                r.CreatedAt = DateTime.Now;
                r.CreatedUserId = job.UserId ?? "";
                r.CreatedFullName = job.FullName ?? "System Administrator";
                r.LastUpdatedAt = DateTime.Now;
                r.LastUpdateUserId = job.UserId ?? "";
                r.LastUpdateFullName = job.FullName ?? "System Administrator";

                // Store child entities in separate lists for bulk insert
                var education = new RecruitEducation()
                {
                    Degree = workSheet?.Cells[row, 18]?.GetValue<string>() ?? "",
                    Major = workSheet?.Cells[row, 19]?.GetValue<string>() == "อื่น ๆ" ? workSheet?.Cells[row, 20]?.GetValue<string>() ?? "" : workSheet?.Cells[row, 19]?.GetValue<string>() ?? "",
                    MajorGroupId = "",
                    MajorGroupName = "",
                    University = workSheet?.Cells[row, 21]?.GetValue<string>() == "อื่น ๆ" ? workSheet?.Cells[row, 22]?.GetValue<string>() ?? "" : workSheet?.Cells[row, 21]?.GetValue<string>() ?? "",
                    GPA = (double)workSheet?.Cells[row, 26]?.GetValue<double>(),
                    Specialist = "",
                    HighDegree = workSheet?.Cells[row, 27]?.GetValue<string>() ?? "",
                    BachelorDate = !string.IsNullOrWhiteSpace(workSheet?.Cells[row, 25]?.GetValue<string>()) ? _recruitService.CheckDateTime(workSheet?.Cells[row, 25]?.GetValue<string>() ?? "", "dd/MM/yyyy") : null,
                    CreatedAt = DateTime.Now,
                    CreatedUserId = job.UserId ?? "",
                    CreatedFullName = job.FullName ?? "System Administrator",
                    LastUpdatedAt = DateTime.Now,
                    LastUpdateUserId = job.UserId ?? "",
                    LastUpdateFullName = job.FullName ?? "System Administrator"
                };

                var occupation = new RecruitOccupation()
                {
                    Occupation = workSheet?.Cells[row, 33]?.GetValue<string>() == "อื่น ๆ" ? workSheet?.Cells[row, 34]?.GetValue<string>() ?? "" : workSheet?.Cells[row, 33]?.GetValue<string>() ?? "",
                    Position = workSheet?.Cells[row, 37]?.GetValue<string>() ?? "",
                    Workplace = $"{(workSheet?.Cells[row, 36]?.GetValue<string>() ?? "")} {(workSheet?.Cells[row, 35]?.GetValue<string>() ?? "")}",
                    Telephone = workSheet?.Cells[row, 9999]?.GetValue<string>() ?? "",
                    WorkAge = workSheet?.Cells[row, 9999]?.GetValue<string>() ?? "",
                    CreatedAt = DateTime.Now,
                    CreatedUserId = job.UserId ?? "",
                    CreatedFullName = job.FullName ?? "System Administrator",
                    LastUpdatedAt = DateTime.Now,
                    LastUpdateUserId = job.UserId ?? "",
                    LastUpdateFullName = job.FullName ?? "System Administrator"
                };

                var address = new RecruitAddress()
                {
                    Address = $"{(workSheet?.Cells[row, 49]?.GetValue<string>() ?? "")} {(workSheet?.Cells[row, 50]?.GetValue<string>() ?? "")}",
                    Moo = workSheet?.Cells[row, 51]?.GetValue<string>() ?? "",
                    Soi = workSheet?.Cells[row, 52]?.GetValue<string>() ?? "",
                    Road = workSheet?.Cells[row, 53]?.GetValue<string>() ?? "",
                    District = workSheet?.Cells[row, 54]?.GetValue<string>() ?? "",
                    Amphur = workSheet?.Cells[row, 55]?.GetValue<string>() ?? "",
                    Province = workSheet?.Cells[row, 56]?.GetValue<string>() ?? "",
                    ZipCode = (workSheet?.Cells[row, 57]?.GetValue<string>() ?? "").Trim(),
                    Telephone = workSheet?.Cells[row, 58]?.GetValue<string>() ?? "",
                    Mobile = "",
                    Address1 = $"{(workSheet?.Cells[row, 61]?.GetValue<string>() ?? "")} {(workSheet?.Cells[row, 62]?.GetValue<string>() ?? "")}",
                    Moo1 = workSheet?.Cells[row, 63]?.GetValue<string>() ?? "",
                    Soi1 = workSheet?.Cells[row, 64]?.GetValue<string>() ?? "",
                    Road1 = workSheet?.Cells[row, 65]?.GetValue<string>() ?? "",
                    District1 = workSheet?.Cells[row, 66]?.GetValue<string>() ?? "",
                    Amphur1 = workSheet?.Cells[row, 67]?.GetValue<string>() ?? "",
                    Province1 = workSheet?.Cells[row, 68]?.GetValue<string>() ?? "",
                    ZipCode1 = (workSheet?.Cells[row, 69]?.GetValue<string>() ?? "").Trim(),
                    CreatedAt = DateTime.Now,
                    CreatedUserId = job.UserId ?? "",
                    CreatedFullName = job.FullName ?? "System Administrator",
                    LastUpdatedAt = DateTime.Now,
                    LastUpdateUserId = job.UserId ?? "",
                    LastUpdateFullName = job.FullName ?? "System Administrator"
                };

                var payment = new RecruitPayment()
                {
                    PaymentId = workSheet?.Cells[row, 104]?.GetValue<string>() ?? "",
                    CompanyCode = workSheet?.Cells[row, 105]?.GetValue<string>() ?? "",
                    TextFile = workSheet?.Cells[row, 106]?.GetValue<string>() ?? "",
                    BankCode = workSheet?.Cells[row, 107]?.GetValue<string>() ?? "",
                    AccountNumber = workSheet?.Cells[row, 108]?.GetValue<string>() ?? "",
                    TransDate = workSheet?.Cells[row, 109]?.GetValue<string>() ?? "",
                    TransTime = workSheet?.Cells[row, 110]?.GetValue<string>() ?? "",
                    CustomerName = workSheet?.Cells[row, 111]?.GetValue<string>() ?? "",
                    RefNo1 = workSheet?.Cells[row, 112]?.GetValue<string>() ?? "",
                    TermBranch = workSheet?.Cells[row, 113]?.GetValue<string>() ?? "",
                    TellerId = workSheet?.Cells[row, 114]?.GetValue<string>() ?? "",
                    CreditDebit = workSheet?.Cells[row, 115]?.GetValue<string>() ?? "",
                    PaymentType = workSheet?.Cells[row, 116]?.GetValue<string>() ?? "",
                    ChequeNo = workSheet?.Cells[row, 117]?.GetValue<string>() ?? "",
                    Amount = (decimal)workSheet?.Cells[row, 118]?.GetValue<decimal>(),
                    ChqueBankCode = workSheet?.Cells[row, 119]?.GetValue<string>() ?? "",
                    CreatedAt = DateTime.Now,
                    CreatedUserId = job.UserId ?? "",
                    CreatedFullName = job.FullName ?? "System Administrator",
                    LastUpdatedAt = DateTime.Now,
                    LastUpdateUserId = job.UserId ?? "",
                    LastUpdateFullName = job.FullName ?? "System Administrator"
                };

                r.Educations.Add(education);
                r.Occupations.Add(occupation);
                r.Addresses.Add(address);
                r.Payments.Add(payment);

                batchRecruits.Add(r);
                batchEducations.Add(education);
                batchOccupations.Add(occupation);
                batchAddresses.Add(address);
                batchPayments.Add(payment);

                row++;
                batchCount++;
                totalProcessed++;

                if (batchCount >= batchSize)
                {
                    // BulkInsert Recruits first (with SetOutputIdentity to get generated Ids)
                    await _context.BulkInsertAsync(batchRecruits, options =>
                    {
                        options.SetOutputIdentity = true;
                    });

                    // Assign generated Recruit Id to child entities
                    for (int j = 0; j < batchRecruits.Count; j++)
                    {
                        batchEducations[j].Recruit = batchRecruits[j];
                        batchOccupations[j].Recruit = batchRecruits[j];
                        batchAddresses[j].Recruit = batchRecruits[j];
                        batchPayments[j].Recruit = batchRecruits[j];
                    }

                    // BulkInsert child entities (no identity output needed)
                    await _context.BulkInsertAsync(batchEducations);
                    await _context.BulkInsertAsync(batchOccupations);
                    await _context.BulkInsertAsync(batchAddresses);
                    await _context.BulkInsertAsync(batchPayments);

                    // Clear all lists for next batch
                    batchRecruits.Clear();
                    batchEducations.Clear();
                    batchOccupations.Clear();
                    batchAddresses.Clear();
                    batchPayments.Clear();
                    batchCount = 0;
                    _tracker.UpdateStatus(job.JobId, ImportJobStatus.Running, totalProcessed);
                }
            }

            // Process remaining records
            if (batchRecruits.Count > 0)
            {
                await _context.BulkInsertAsync(batchRecruits, options =>
                {
                    options.SetOutputIdentity = true;
                });

                for (int j = 0; j < batchRecruits.Count; j++)
                {
                    batchEducations[j].Recruit = batchRecruits[j];
                    batchOccupations[j].Recruit = batchRecruits[j];
                    batchAddresses[j].Recruit = batchRecruits[j];
                    batchPayments[j].Recruit = batchRecruits[j];
                }

                await _context.BulkInsertAsync(batchEducations);
                await _context.BulkInsertAsync(batchOccupations);
                await _context.BulkInsertAsync(batchAddresses);
                await _context.BulkInsertAsync(batchPayments);
            }
        }

        job.TotalCount = _tracker.GetJob(job.JobId)?.ProcessedCount ?? 0;
    }

    #endregion

    #region ScoreFile

    private async Task ProcessScoreFileAsync(ApplicationDbContext _context, MinIOService _minioService, RecruitService _recruitService, ImportJobInfo job)
    {
        var rec_import = await _context.RecruitImports.AsQueryable()
                                .Include(x => x.ScoreImport)
                                .ThenInclude(x => x.Scores)
                                .Include(x => x.ImportHostories)
                                .FirstOrDefaultAsync(x => x.Id == job.RecruitImportId);

        if (rec_import == null) throw new Exception("RecruitImport not found");

        if (rec_import.ScoreImport != null && rec_import.ScoreImport.Scores != null)
        {
            await _context.BulkDeleteAsync(rec_import.ScoreImport.Scores.ToList());
        }

        rec_import.ImportHostories.Add(new RecruitImportHistory
        {
            Description = "นำเข้าข้อมูลผลคะแนนสอบ",
            CreatedAt = DateTime.Now,
            CreatedUserId = job.UserId ?? "",
            CreatedFullName = job.FullName ?? "System Administrator",
            LastUpdatedAt = DateTime.Now,
            LastUpdateUserId = job.UserId ?? "",
            LastUpdateFullName = job.FullName ?? "System Administrator",
        });

        // get doc from minio
        var doc = await _minioService.UploadFileAsync(new DummyFormFile(job.ImportFile));
        var imported = new ScoreImport
        {
            Year = rec_import.Year,
            ImportFile = doc,
            CreatedAt = DateTime.Now,
            CreatedUserId = job.UserId ?? "",
            CreatedFullName = job.FullName ?? "System Administrator",
            LastUpdatedAt = DateTime.Now,
            LastUpdateUserId = job.UserId ?? "",
            LastUpdateFullName = job.FullName ?? "System Administrator",
            Scores = new List<RecruitScore>()
        };

        // Save ScoreImport parent first to get its Id
        rec_import.ScoreImport = imported;
        await _context.SaveChangesAsync();
        _context.ChangeTracker.Clear();

        // preload recruits (lightweight - only ExamId)
        var recruitsDict = await _context.Recruits
            .Where(x => x.RecruitImport.Id == rec_import.Id)
            .GroupBy(x => x.ExamId)
            .Where(g => g.Count() == 1)
            .Select(g => g.First())
            .ToDictionaryAsync(x => x.ExamId, x => x);

        using var c_package = new ExcelPackage(new FileInfo(job.ImportFile));
        for (int i = 0; i < c_package.Workbook.Worksheets.Count; i++)
        {
            var workSheet = c_package.Workbook.Worksheets[i];
            var cols = workSheet.GetHeaderColumns();
            int row = 8;
            int batchCount = 0;
            const int batchSize = 500;
            int totalProcessed = 0;
            var endRow = workSheet.Dimension.End.Row;

            var batchScores = new List<RecruitScore>();

            while (row <= endRow)
            {
                var cell1 = workSheet?.Cells[row, 1]?.GetValue<string>();
                if (cell1 == "" || cell1 == null) break;

                var r = new RecruitScore();
                r.ExamId = workSheet?.Cells[row, 2]?.GetValue<string>();

                if (!string.IsNullOrEmpty(r.ExamId) && recruitsDict.TryGetValue(r.ExamId, out var recruit))
                {
                    r.CitizenId = workSheet?.Cells[row, 3]?.GetValue<string>()?.Trim();
                    r.FullA = 200;
                    r.SumA = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 5]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 5].GetValue<double>(), 2);
                    r.PercentageA = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 6]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 6].GetValue<double>(), 2);
                    r.AStatus = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 7]?.GetValue<string>()) ? "" : workSheet?.Cells[row, 7]?.GetValue<string>();
                    r.SumAB = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 5]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 5].GetValue<double>(), 2);
                    r.ABStatus = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 7]?.GetValue<string>()) ? "" : workSheet?.Cells[row, 7]?.GetValue<string>();
                    r.FullC = 50;
                    r.SumC = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 8]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 8].GetValue<double>(), 2);
                    r.FullD = 50;
                    r.SumD = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 9]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 9].GetValue<double>(), 2);
                    r.SumCD = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 10]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 10].GetValue<double>(), 2);
                    r.PercentageC = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 11]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 11].GetValue<double>(), 2);
                    r.CStatus = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 12]?.GetValue<string>()) ? "" : workSheet?.Cells[row, 12]?.GetValue<string>();
                    r.FullScore = 300;
                    r.TotalScore = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 13]?.GetValue<string>()) ? 0.00 : Math.Round(workSheet.Cells[row, 13].GetValue<double>(), 2);

                    var examStatusCol7 = workSheet?.Cells[row, 7]?.GetValue<string>()?.Trim();
                    var examStatusCol14 = workSheet?.Cells[row, 14]?.GetValue<string>()?.Trim();
                    r.ExamStatus =
                        examStatusCol7 == "ขาดสอบ" ? "ขส." :
                        examStatusCol14 == "ได้" ? "ผ่าน" :
                        examStatusCol14 == "ตก" ? "ไม่ผ่าน" : "-";

                    r.RemarkScore = string.IsNullOrWhiteSpace(workSheet?.Cells[row, 15]?.GetValue<string>()) ? string.Empty : workSheet?.Cells[row, 15]?.GetValue<string>();

                    var examAttr = workSheet?.Cells[row, 16]?.GetValue<string>()?.Trim();
                    r.ExamAttribute =
                        examAttr == "ผ่าน" ? "มีคุณสมบัติ" :
                        examAttr == "ไม่ผ่าน" ? "ไม่มีคุณสมบัติ" : "";

                    r.Major = workSheet.Name;
                    r.CreatedAt = DateTime.Now;
                    r.CreatedUserId = job.UserId ?? "";
                    r.CreatedFullName = job.FullName ?? "System Administrator";
                    r.LastUpdatedAt = DateTime.Now;
                    r.LastUpdateUserId = job.UserId ?? "";
                    r.LastUpdateFullName = job.FullName ?? "System Administrator";
                    r.ScoreImport = imported;

                    batchScores.Add(r);
                }

                row++;
                batchCount++;
                totalProcessed++;

                if (batchCount >= batchSize)
                {
                    await _context.BulkInsertAsync(batchScores);
                    batchScores.Clear();
                    batchCount = 0;
                    _tracker.UpdateStatus(job.JobId, ImportJobStatus.Running, totalProcessed);
                }
            }

            // Process remaining records
            if (batchScores.Count > 0)
            {
                await _context.BulkInsertAsync(batchScores);
            }
        }

        job.TotalCount = _tracker.GetJob(job.JobId)?.ProcessedCount ?? 0;
    }

    #endregion

    #region ResultFile

    private async Task ProcessResultFileAsync(ApplicationDbContext _context, RecruitService _recruitService, ImportJobInfo job)
    {
        var rec_import = await _context.RecruitImports.AsQueryable()
                                .Include(x => x.ScoreImport)
                                .ThenInclude(x => x.Scores)
                                .Include(x => x.ImportHostories)
                                .FirstOrDefaultAsync(x => x.Id == job.RecruitImportId);

        if (rec_import == null) throw new Exception("RecruitImport not found");

        // update old scores
        if (rec_import.ScoreImport != null && rec_import.ScoreImport.Scores != null)
        {
            var oldScores = rec_import.ScoreImport.Scores
                .Where(x => !string.IsNullOrEmpty(x.Number))
                .ToList();
            if (oldScores.Count > 0)
            {
                foreach (var x in oldScores)
                {
                    x.Number = string.Empty;
                    x.RemarkExamOrder = string.Empty;
                }
                await _context.BulkUpdateAsync(oldScores);
            }
        }

        rec_import.ImportHostories.Add(new RecruitImportHistory
        {
            Description = "นำเข้าข้อมูลผลการสอบ",
            CreatedAt = DateTime.Now,
            CreatedUserId = job.UserId ?? "",
            CreatedFullName = job.FullName ?? "System Administrator",
            LastUpdatedAt = DateTime.Now,
            LastUpdateUserId = job.UserId ?? "",
            LastUpdateFullName = job.FullName ?? "System Administrator",
        });
        await _context.SaveChangesAsync();
        _context.ChangeTracker.Clear();

        // preload scores - re-query from DB to avoid tracking issues
        var scoreList = await _context.RecruitScores
            .Where(s => s.ScoreImport.RecruitImportId == rec_import.Id && !string.IsNullOrEmpty(s.ExamId))
            .GroupBy(x => x.ExamId)
            .Where(g => g.Count() == 1)
            .Select(g => g.First())
            .ToListAsync();
        var score = scoreList.ToDictionary(s => s.ExamId!, s => s);

        // Read from saved file (ResultFile uses stream from Form, but we saved to disk)
        using var stream = System.IO.File.OpenRead(job.ImportFile);
        using var c_package = new ExcelPackage(stream);

        foreach (var workSheet in c_package.Workbook.Worksheets)
        {
            int row = 7;
            int batchCount = 0;
            const int batchSize = 500;
            var endRow = workSheet.Dimension.End.Row;
            var batchUpdates = new List<RecruitScore>();

            while (row <= endRow)
            {
                var examId = workSheet?.Cells[row, 2]?.GetValue<string>();
                if (string.IsNullOrWhiteSpace(examId))
                {
                    row++;
                    continue;
                }

                if (score.TryGetValue(examId, out var existingScore))
                {
                    existingScore.Number = workSheet?.Cells[row, 1]?.GetValue<string>();
                    existingScore.RemarkExamOrder = workSheet?.Cells[row, 4]?.GetValue<string>() ?? string.Empty;
                    existingScore.LastUpdatedAt = DateTime.Now;
                    existingScore.LastUpdateUserId = job.UserId ?? "";
                    existingScore.LastUpdateFullName = job.FullName ?? "System Administrator";
                    batchUpdates.Add(existingScore);
                    batchCount++;
                }

                row++;

                if (batchCount >= batchSize)
                {
                    await _context.BulkUpdateAsync(batchUpdates);
                    batchUpdates.Clear();
                    batchCount = 0;
                }
            }

            // Process remaining records
            if (batchUpdates.Count > 0)
            {
                await _context.BulkUpdateAsync(batchUpdates);
            }
        }
    }

    #endregion

    #region Helpers

    private static int GetColumnIndex(string[] columns, string name, bool partial = false)
    {
        try
        {
            if (partial)
                return Array.FindIndex(columns, x => x.Contains(name)) + 1;
            else
                return Array.FindIndex(columns, x => x == name) + 1;
        }
        catch
        {
            return 0;
        }
    }

    #endregion
}

// Helper class to wrap a file path as IFormFile for MinIO upload
internal class DummyFormFile : IFormFile
{
    private readonly string _filePath;
    private readonly FileInfo _fileInfo;

    public DummyFormFile(string filePath)
    {
        _filePath = filePath;
        _fileInfo = new FileInfo(filePath);
    }

    public string ContentType => "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
    public string ContentDisposition => $"form-data; name=\"file\"; filename=\"{_fileInfo.Name}\"";
    public IHeaderDictionary Headers => new HeaderDictionary();
    public long Length => _fileInfo.Length;
    public string Name => "file";
    public string FileName => _fileInfo.Name;

    public void CopyTo(Stream target)
    {
        using var stream = _fileInfo.OpenRead();
        stream.CopyTo(target);
    }

    public async Task CopyToAsync(Stream target, CancellationToken cancellationToken = default)
    {
        using var stream = _fileInfo.OpenRead();
        await stream.CopyToAsync(target, cancellationToken);
    }

    public Stream OpenReadStream()
    {
        return _fileInfo.OpenRead();
    }
}