using General_Ledger_Service.DTOs.Reports;
using QuestPDF.Fluent;
using QuestPDF.Helpers;
using QuestPDF.Infrastructure;

namespace General_Ledger_Service.Services.PdfDocuments
{
    // 05_LKAS_Report_PDF_Templates.md Section 5 (LKAS 7, full statement). Retrofit 2026-07-22:
    // no printed opening/closing cash balance (still in the Json/Csv data for the reconciliation
    // check, just not displayed here, matching the reference template); nonCashAdjustments and
    // workingCapitalChanges are combined and re-bucketed by sign at render time into "Additions
    // to Cash"/"Subtractions From Cash" rather than kept as two separate lists. Working-capital
    // lines now use the account's own Direction ("Increase"/"Decrease") for their wording, since
    // that's no longer derivable from ChangeAmount's sign alone (see the DTO's comment).
    public class CashFlowPdfDocument(string companyName, string currencyCode, CashFlowReportDto data) : IDocument
    {
        private record CashMovementLine(string Description, decimal Amount);

        public DocumentMetadata GetMetadata() => DocumentMetadata.Default;

        public void Compose(IDocumentContainer container)
        {
            var operating = data.OperatingActivities;
            var operatingProfitBeforeWorkingCapital = operating.ProfitForPeriod + operating.NonCashAdjustments.Sum(a => a.Amount);

            var movements = operating.NonCashAdjustments
                .Select(a => new CashMovementLine(a.Description, a.Amount))
                .Concat(operating.WorkingCapitalChanges.Select(c => new CashMovementLine($"{c.Direction} in {c.AccountName}", c.ChangeAmount)))
                .ToList();
            var additions = movements.Where(m => m.Amount > 0).ToList();
            var subtractions = movements.Where(m => m.Amount <= 0).ToList();

            container.Page(page =>
            {
                page.Size(PageSizes.A4);
                page.Margin(2, Unit.Centimetre);
                ReportPageHeader.Compose(page, companyName, "Statement of Cash Flows", ReportPageHeader.RangePeriodLine(data.PeriodStart, data.PeriodEnd), currencyCode);

                page.Content().PaddingTop(10).Column(column =>
                {
                    column.Item().Text("Cash Flows from Operating Activities").Bold();
                    column.Item().Row(r =>
                    {
                        r.RelativeItem(4).Text("Profit for the period");
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(operating.ProfitForPeriod));
                    });
                    column.Item().Row(r =>
                    {
                        r.RelativeItem(4).Text("Operating profit before working capital changes");
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(operatingProfitBeforeWorkingCapital));
                    });

                    if (additions.Count > 0)
                    {
                        column.Item().PaddingTop(5).Text("Additions to Cash");
                        foreach (var line in additions)
                        {
                            column.Item().PaddingLeft(10).Row(r =>
                            {
                                r.RelativeItem(4).Text(line.Description);
                                r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(line.Amount));
                            });
                        }
                    }

                    if (subtractions.Count > 0)
                    {
                        column.Item().PaddingTop(5).Text("Subtractions From Cash");
                        foreach (var line in subtractions)
                        {
                            column.Item().PaddingLeft(10).Row(r =>
                            {
                                r.RelativeItem(4).Text(line.Description);
                                r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(line.Amount));
                            });
                        }
                    }

                    column.Item().PaddingTop(3).LineHorizontal(1);
                    column.Item().Row(r =>
                    {
                        r.RelativeItem(4).Text("Net Cash from Operating Activities").Bold();
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(operating.NetCashFromOperatingActivities)).Bold();
                    });

                    column.Item().PaddingTop(15).Text("Cash Flows from Investing Activities").Bold();
                    foreach (var line in data.InvestingActivities.Lines)
                    {
                        column.Item().Row(r =>
                        {
                            r.RelativeItem(4).Text(line.AccountName);
                            r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(line.Amount));
                        });
                    }
                    column.Item().PaddingTop(3).LineHorizontal(1);
                    column.Item().Row(r =>
                    {
                        var label = data.InvestingActivities.NetCashFromInvestingActivities < 0 ? "Net Cash used in Investing Activities" : "Net Cash from Investing Activities";
                        r.RelativeItem(4).Text(label).Bold();
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(data.InvestingActivities.NetCashFromInvestingActivities)).Bold();
                    });

                    column.Item().PaddingTop(15).Text("Cash Flows from Financing Activities").Bold();
                    foreach (var line in data.FinancingActivities.Lines)
                    {
                        column.Item().Row(r =>
                        {
                            r.RelativeItem(4).Text(line.AccountName);
                            r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(line.Amount));
                        });
                    }
                    column.Item().PaddingTop(3).LineHorizontal(1);
                    column.Item().Row(r =>
                    {
                        var label = data.FinancingActivities.NetCashFromFinancingActivities < 0 ? "Net Cash used in Financing Activities" : "Net Cash from Financing Activities";
                        r.RelativeItem(4).Text(label).Bold();
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(data.FinancingActivities.NetCashFromFinancingActivities)).Bold();
                    });

                    column.Item().PaddingTop(15).LineHorizontal(1.5f);
                    column.Item().Row(r =>
                    {
                        var label = data.NetIncreaseDecreaseInCash < 0 ? "Net Decrease in Cash and Cash Equivalents" : "Net Increase in Cash and Cash Equivalents";
                        r.RelativeItem(4).Text(label).Bold();
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(data.NetIncreaseDecreaseInCash)).Bold();
                    });
                });
            });
        }
    }
}