using QuestPDF.Fluent;
using QuestPDF.Helpers;
using QuestPDF.Infrastructure;
using System.IO;
using System.Collections.Generic;
using PSTW_CentralSystem.Areas.OTcalculate.Models;
using System;

namespace PSTW_CentralSystem.Areas.OTcalculate.Services
{
    public class OvertimePdfService
    {
    public MemoryStream GenerateOvertimeTablePdf(
    List<OtRegisterModel> records,
    int departmentId,
    string userFullName,
    string departmentName,
    byte[]? logoImage = null // Optional logo image
)
        {
            records = records
                .OrderBy(r => r.OtDate)
                .ToList();

            var stream = new MemoryStream();

            Document.Create(container =>
            {
                container.Page(page =>
                {
                    page.Size(PageSizes.A4.Landscape());
                    page.Margin(30);

                    // Header section with logo and user info
                    page.Content().Column(column =>
                    {
                        column.Item().Row(row =>
                        {
                            row.RelativeItem(2).Column(col =>
                            {


                                if (logoImage != null)
                                {
                                    col.Item().Container().Height(36).Image(logoImage, ImageScaling.FitArea);
                                    col.Spacing(10);
                                }

                                col.Item().Text($"Name: {userFullName}").FontSize(9).SemiBold();
                                col.Item().Text($"Department: {departmentName}").FontSize(9).Italic();
                                col.Item().Text($"Overtime Record: { GetMonthYearString(records)}").FontSize(9).Italic();
                            });

                            row.RelativeItem(1).AlignRight().Text($"Generated: {DateTime.Now:dd MMM yyyy HH:mm}")
                                .FontSize(9).FontColor(Colors.Grey.Medium);
                        });


                        column.Item().PaddingVertical(10).LineHorizontal(0.5f).LineColor(Colors.Grey.Lighten2);

                        // Table section
                        column.Item().Table(table =>
                        {
                            table.ColumnsDefinition(columns =>
                            {
                                columns.RelativeColumn(1.1f); // Date
                                columns.RelativeColumn(0.8f); // Office From
                                columns.RelativeColumn(0.8f); // Office To
                                columns.RelativeColumn(0.8f); // Office Break
                                columns.RelativeColumn(0.9f); // Outside From
                                columns.RelativeColumn(0.9f); // Outside To
                                columns.RelativeColumn(0.9f); // Outside Break
                                columns.RelativeColumn(); // Total OT
                                columns.RelativeColumn(); // Break Hours
                                columns.RelativeColumn(); // Net OT
                                if (departmentId == 2)
                                    columns.RelativeColumn(); // Station
                                columns.RelativeColumn(0.9f); // Day Type
                                columns.RelativeColumn(2.7f); // Description
                            });

                            // Header Row
                            table.Header(header =>
                            {
                                void AddHeaderCell(string text, string bgColor)
                                {
                                    header.Cell().Background(bgColor).Border(0.25f).Padding(5).Text(text).FontSize(9).Bold().AlignCenter();
                                }

                                AddHeaderCell("Date", "#d0ead2");
                                AddHeaderCell("From\n(Office)", "#dceefb");
                                AddHeaderCell("To\n(Office)", "#dceefb");
                                AddHeaderCell("Break\n(Office)", "#dceefb");
                                AddHeaderCell("From\n(Outside)", "#edf2f7");
                                AddHeaderCell("To\n(Outside)", "#edf2f7");
                                AddHeaderCell("Break\n(Outside)", "#edf2f7");
                                AddHeaderCell("Total OT\nHours", "#fdebd0");
                                AddHeaderCell("Break Hours\n(min)", "#fdebd0");
                                AddHeaderCell("Net OT", "#fdebd0");
                                if (departmentId == 2)
                                    AddHeaderCell("Station", "#d0f0ef");
                                AddHeaderCell("Days", "#e0f7da");
                                AddHeaderCell("Description", "#e3f2fd");
                            });

                            // Data Rows
                            // Data Rows
                            double totalOTSum = 0;
                            int totalBreakSum = 0;
                            TimeSpan totalNetOt = TimeSpan.Zero;
                            bool alternate = false;

                            if (!records.Any())
                            {
                                // Show message row if no records
                                uint colspan = (uint)(departmentId == 2 ? 13 : 12);

                                table.Cell().ColumnSpan(colspan)
                                    .Border(0.5f)
                                    .Padding(10)
                                    .AlignCenter()
                                    .Text("No records found for selected month and year.")
                                    .FontSize(10)
                                    .FontColor(Colors.Grey.Darken2)
                                    .Italic();
                            }

                            else
                            {
                                foreach (var r in records)
                                {
                                    var totalOT = CalculateTotalOT(r);
                                    var totalBreak = (r.OfficeBreak ?? 0) + (r.OutsideBreak ?? 0);
                                    var netOT = totalOT - TimeSpan.FromMinutes(totalBreak);

                                    totalOTSum += totalOT.TotalHours;
                                    totalBreakSum += totalBreak;
                                    totalNetOt += netOT;

                                    string rowBg = alternate ? "#f9f9f9" : "#ffffff";
                                    alternate = !alternate;

                                    void AddCell(string value, bool alignLeft = false)
                                    {
                                        var text = table.Cell().Background(rowBg).Border(0.25f).Padding(5).Text(value).FontSize(9);
                                        if (alignLeft)
                                            text.AlignLeft();
                                        else
                                            text.AlignCenter();
                                    }

                                    AddCell(r.OtDate.ToString("dd/MM/yyyy"));
                                    AddCell(FormatTime(r.OfficeFrom));
                                    AddCell(FormatTime(r.OfficeTo));
                                    AddCell($"{r.OfficeBreak ?? 0} min");
                                    AddCell(FormatTime(r.OutsideFrom));
                                    AddCell(FormatTime(r.OutsideTo));
                                    AddCell($"{r.OutsideBreak ?? 0} min");
                                    AddCell($"{(int)totalOT.TotalHours} hr {totalOT.Minutes} min");
                                    AddCell($"{totalBreak}");
                                    AddCell($"{netOT.Hours} hr {netOT.Minutes} min");
                                    if (departmentId == 2)
                                        AddCell(r.Stations?.StationName ?? "N/A");
                                    AddCell(r.OtDays);
                                    table.Cell().Background(rowBg).Border(0.25f).Padding(5).Text(r.OtDescription ?? "-").FontSize(9).WrapAnywhere().LineHeight(1.2f);
                                }

                                // Totals Row
                                var totalOTTimeSpan = TimeSpan.FromHours(totalOTSum);
                                var totalBreakTimeSpan = TimeSpan.FromMinutes(totalBreakSum);

                                int totalCols = departmentId == 2 ? 13 : 12;
                                int spanCols = departmentId == 2 ? 7 : 6;

                                for (int i = 0; i < spanCols; i++)
                                    table.Cell().Background("#d8d1f5").Border(0.80f).Padding(5).Text(i == 0 ? "TOTAL" : "").Bold().FontSize(9).AlignCenter();

                                table.Cell().Background("#d8d1f5").Border(0.80f).Padding(5).Text($"{(int)totalOTTimeSpan.TotalHours} hr {totalOTTimeSpan.Minutes} min").Bold().FontSize(9).AlignCenter();
                                table.Cell().Background("#d8d1f5").Border(0.80f).Padding(5).Text($"{(int)totalBreakTimeSpan.TotalHours} hr {totalBreakTimeSpan.Minutes} min").Bold().FontSize(9).AlignCenter();
                                table.Cell().Background("#d8d1f5").Border(0.80f).Padding(5).Text($"{(int)totalNetOt.TotalHours} hr {totalNetOt.Minutes} min").Bold().FontSize(9).AlignCenter();
                                if (departmentId == 2)
                                    table.Cell().Background("#d8d1f5").Border(0.80f);
                                else
                                    table.Cell().Background("#d8d1f5").Border(0.80f);
                                table.Cell().Background("#d8d1f5").Border(0.80f);
                                table.Cell().Background("#d8d1f5").Border(0.80f);
                            }

                        });

                    });
                });
            }).GeneratePdf(stream);

            stream.Position = 0;
            return stream;
        }


        private TimeSpan CalculateTotalOT(OtRegisterModel r)
        {
            TimeSpan office = (r.OfficeTo ?? TimeSpan.Zero) - (r.OfficeFrom ?? TimeSpan.Zero);
            TimeSpan outside = (r.OutsideTo ?? TimeSpan.Zero) - (r.OutsideFrom ?? TimeSpan.Zero);

            if (outside < TimeSpan.Zero)
                outside += TimeSpan.FromHours(24);

            return office + outside;
        }

        private string FormatTime(TimeSpan? time)
        {
            return time?.ToString(@"hh\:mm") ?? "-";
        }
        private string GetMonthYearString(List<OtRegisterModel> records)
        {
            if (records == null || !records.Any())
                return "No Data";

            var firstDate = records.First().OtDate;
            return $"{firstDate:MMMM yyyy}";
        }


    }
}