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 4 (LKAS 1). Retrofit 2026-07-22: restructured
    // around accounts.income_statement_section - Sales/Cost of Sales -> Gross Profit, then
    // Other Income and four expense groups -> Net Profit for the Period. Both GrossProfit and
    // NetProfitForPeriod are already computed server-side (ReportService.BuildProfitAndLossReportAsync).
    public class ProfitAndLossPdfDocument(string companyName, string currencyCode, ProfitAndLossReportDto data) : IDocument
    {
        public DocumentMetadata GetMetadata() => DocumentMetadata.Default;

        public void Compose(IDocumentContainer container)
        {
            container.Page(page =>
            {
                page.Size(PageSizes.A4);
                page.Margin(2, Unit.Centimetre);
                ReportPageHeader.Compose(page, companyName, "Statement of Profit or Loss", ReportPageHeader.RangePeriodLine(data.PeriodStart, data.PeriodEnd), currencyCode);

                page.Content().PaddingTop(10).Column(column =>
                {
                    ComposeSection(column, "Sales", data.Sales);
                    ComposeSection(column, "Cost of Sales", data.CostOfSales);
                    ComposeTotal(column, "GROSS PROFIT", data.GrossProfit, topRule: true);

                    ComposeSection(column, "Other Income", data.OtherIncome);
                    ComposeSection(column, "Distribution Expenses", data.DistributionExpenses);
                    ComposeSection(column, "Administration Expenses", data.AdministrationExpenses);
                    ComposeSection(column, "Other Expenses", data.OtherExpenses);
                    ComposeSection(column, "Financial Expenses", data.FinancialExpenses);

                    if (data.Unclassified.Lines.Count > 0)
                    {
                        ComposeSection(column, "Unclassified", data.Unclassified);
                    }

                    ComposeTotal(column, "NET PROFIT FOR THE PERIOD", data.NetProfitForPeriod, topRule: true, doubleRule: true);
                });
            });
        }

        private static void ComposeSection(ColumnDescriptor column, string title, ProfitAndLossSectionDto section)
        {
            if (section.Lines.Count == 0)
            {
                return;
            }

            column.Item().PaddingTop(10).Text(title).Bold();
            foreach (var line in section.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 =>
            {
                r.RelativeItem(4).Text($"Total {title}").Bold();
                r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(section.Total)).Bold();
            });
        }

        private static void ComposeTotal(ColumnDescriptor column, string label, decimal amount, bool topRule, bool doubleRule = false)
        {
            if (topRule)
            {
                column.Item().PaddingTop(10).LineHorizontal(doubleRule ? 1.5f : 1);
            }

            column.Item().Row(r =>
            {
                r.RelativeItem(4).Text(label).Bold();
                r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(amount)).Bold();
            });
        }
    }
}