using ClosedXML.Excel;
using System.IO;
using PSTW_CentralSystem.Models;
using PSTW_CentralSystem.Areas.OTcalculate.Models;
using System;
using System.Collections.Generic;
using System.Linq;

namespace PSTW_CentralSystem.Areas.OTcalculate.Services
{
    public class OvertimeExcelService
    {
        public MemoryStream GenerateOvertimeExcel(
            List<OtRegisterModel> records,
            int departmentId,
            string userFullName,
            string departmentName,
            int userStateId,
            int weekendId,
            List<CalendarModel> publicHolidays,
            bool isAdminUser = false,
            byte[]? logoImage = null // This parameter is missing in the call
        )
        {
            var workbook = new XLWorkbook();
            var worksheet = workbook.Worksheets.Add("Overtime Records");
            int currentRow = 1;

            // Add Header Information
            if (!string.IsNullOrEmpty(userFullName))
            {
                worksheet.Cell(currentRow, 1).Value = $"Name: {userFullName}";
                currentRow++;
            }
            if (!string.IsNullOrEmpty(departmentName))
            {
                worksheet.Cell(currentRow, 1).Value = $"Department: {departmentName}";
                currentRow++;
            }
            currentRow++; // Add an empty row after header

            // Header titles
            var headers = new List<string>
            {
                "Day", "Date", "Office From", "Office To", "Office Break",
                "After From", "After To", "After Break",
                "Total OT", "Break Minutes", "Net OT"
            };

            if (departmentId == 2 || isAdminUser)
                headers.Add("Station");

            headers.Add("Description");

            // Set header row
            int headerRow = currentRow;
            for (int i = 0; i < headers.Count; i++)
            {
                var cell = worksheet.Cell(headerRow, i + 1);
                cell.Value = headers[i];
                cell.Style.Font.Bold = true;
                cell.Style.Fill.BackgroundColor = XLColor.LightGray;
                cell.Style.Alignment.Horizontal = XLAlignmentHorizontalValues.Center;
                cell.Style.Border.OutsideBorder = XLBorderStyleValues.Thin;
                cell.Style.Border.InsideBorder = XLBorderStyleValues.Thin;
            }
            currentRow++;

            // Fill data rows
            foreach (var r in records)
            {
                TimeSpan totalOT = CalculateTotalOT(r);
                int totalBreak = (r.OfficeBreak ?? 0) + (r.AfterBreak ?? 0);
                TimeSpan netOT = totalOT - TimeSpan.FromMinutes(totalBreak);

                int col = 1;
                var dayCell = worksheet.Cell(currentRow, col++);
                dayCell.Value = r.OtDate.ToString("ddd");
                dayCell.Style.Alignment.Horizontal = XLAlignmentHorizontalValues.Center;
                dayCell.Style.Border.OutsideBorder = XLBorderStyleValues.Thin;
                dayCell.Style.Border.InsideBorder = XLBorderStyleValues.Thin;

                var dateCell = worksheet.Cell(currentRow, col++);
                dateCell.Value = r.OtDate.ToString("yyyy-MM-dd");
                dateCell.Style.Alignment.Horizontal = XLAlignmentHorizontalValues.Center;
                dateCell.Style.Border.OutsideBorder = XLBorderStyleValues.Thin;
                dateCell.Style.Border.InsideBorder = XLBorderStyleValues.Thin;

                // Apply background color for weekends and public holidays
                var dayOfWeek = r.OtDate.DayOfWeek;
                bool isWeekend = (weekendId == 1 && (dayOfWeek == DayOfWeek.Friday || dayOfWeek == DayOfWeek.Saturday)) ||
                                 (weekendId == 2 && (dayOfWeek == DayOfWeek.Saturday || dayOfWeek == DayOfWeek.Sunday));
                bool isPublicHoliday = publicHolidays.Any(h => h.HolidayDate.Date == r.OtDate.Date);

                if (isPublicHoliday)
                {
                    dayCell.Style.Fill.BackgroundColor = XLColor.Pink;
                    dateCell.Style.Fill.BackgroundColor = XLColor.Pink;
                }
                else if (isWeekend)
                {
                    dayCell.Style.Fill.BackgroundColor = XLColor.LightBlue;
                    dateCell.Style.Fill.BackgroundColor = XLColor.LightBlue;
                }

                worksheet.Cell(currentRow, col++).Value = FormatTime(r.OfficeFrom);
                worksheet.Cell(currentRow, col++).Value = FormatTime(r.OfficeTo);
                worksheet.Cell(currentRow, col++).Value = r.OfficeBreak;

                worksheet.Cell(currentRow, col++).Value = FormatTime(r.AfterFrom);
                worksheet.Cell(currentRow, col++).Value = FormatTime(r.AfterTo);
                worksheet.Cell(currentRow, col++).Value = r.AfterBreak;

                worksheet.Cell(currentRow, col++).Value = totalOT.ToString(@"hh\:mm");
                worksheet.Cell(currentRow, col++).Value = totalBreak;
                worksheet.Cell(currentRow, col++).Value = netOT.ToString(@"hh\:mm");

                if (departmentId == 2 || isAdminUser)
                    worksheet.Cell(currentRow, col++).Value = r.Stations?.StationName ?? "";

                worksheet.Cell(currentRow, col++).Value = r.OtDescription ?? "";

                // Apply border and alignment for the rest of the row
                for (int i = headers.IndexOf("Office From") + 1; i <= headers.Count; i++)
                {
                    var cell = worksheet.Cell(currentRow, i);
                    cell.Style.Alignment.Horizontal = XLAlignmentHorizontalValues.Center;
                    cell.Style.Border.OutsideBorder = XLBorderStyleValues.Thin;
                    cell.Style.Border.InsideBorder = XLBorderStyleValues.Thin;
                }

                currentRow++;
            }

            // Add Total row
            int totalRow = currentRow;
            worksheet.Cell(totalRow, 1).Value = "TOTAL";
            worksheet.Cell(totalRow, 1).Style.Font.Bold = true;
            worksheet.Cell(totalRow, headers.IndexOf("Total OT") + 1).Value = $"=SUM(I{headerRow + 1}:I{totalRow - 1})";
            worksheet.Cell(totalRow, headers.IndexOf("Total OT") + 1).Style.Font.Bold = true;
            worksheet.Cell(totalRow, headers.IndexOf("Break Minutes") + 1).Value = $"=SUM(J{headerRow + 1}:J{totalRow - 1})";
            worksheet.Cell(totalRow, headers.IndexOf("Break Minutes") + 1).Style.Font.Bold = true;
            worksheet.Cell(totalRow, headers.IndexOf("Net OT") + 1).Value = $"=SUM(K{headerRow + 1}:K{totalRow - 1})";
            worksheet.Cell(totalRow, headers.IndexOf("Net OT") + 1).Style.Font.Bold = true;

            worksheet.Columns().AdjustToContents();

            var stream = new MemoryStream();
            workbook.SaveAs(stream);
            stream.Position = 0;
            return stream;
        }

        private TimeSpan CalculateTotalOT(OtRegisterModel r)
        {
            TimeSpan office = (r.OfficeTo ?? TimeSpan.Zero) - (r.OfficeFrom ?? TimeSpan.Zero);
            TimeSpan after = (r.AfterTo ?? TimeSpan.Zero) - (r.AfterFrom ?? TimeSpan.Zero);
            if (after < TimeSpan.Zero)
                after += TimeSpan.FromHours(24);
            return office + after;
        }

        private string FormatTime(TimeSpan? time)
        {
            return time == null || time == TimeSpan.Zero ? "" : time.Value.ToString(@"hh\:mm");
        }
    }
}