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 8, redesigned 2026-07-22 - Accounting_System_Design_LKAS.md
    // Section 11.7. A single Profit-Before-Tax-to-Balance-Tax-Payable computation (current tax
    // only, no deferred tax) - the standard corporate income tax return shape, replacing the
    // 2026-07-21 VAT/WHT/NBT per-tax_code summary entirely. Uses the fuller company identity
    // block (address/TIN/BRN) since a tax computation conventionally carries those.
    public class IncomeTaxComputationPdfDocument(string companyName, string companyAddress, string companyTin, string companyBrn, string currencyCode, IncomeTaxComputationDto 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.ComposeWithEntityDetails(
                    page, companyName, companyAddress, companyTin, companyBrn,
                    "Income Tax Computation", ReportPageHeader.RangePeriodLine(data.PeriodStart, data.PeriodEnd), currencyCode);

                page.Content().PaddingTop(10).Column(column =>
                {
                    Line(column, "Profit Before Tax", data.ProfitBeforeTax);
                    Line(column, "Add: Non-Deductible Expenses", data.NonDeductibleExpenses);
                    Line(column, "Less: Allowable Deductions", -data.AllowableDeductions);
                    Total(column, "Adjusted Business Profit", data.AdjustedBusinessProfit);

                    Line(column, "Add: Other Taxable Income", data.OtherTaxableIncome);
                    Total(column, "Assessable Income", data.AssessableIncome);

                    Line(column, "Less: Qualifying Payments / Reliefs", -data.QualifyingPaymentsReliefs);
                    Total(column, "Taxable Income", data.TaxableIncome);

                    column.Item().PaddingTop(10).Row(r =>
                    {
                        r.RelativeItem(4).Text($"Corporate Income Tax @ {data.TaxRatePercent:0.00}%");
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(data.CorporateIncomeTax));
                    });
                    Line(column, "Add: Surcharge / Education Levy", data.SurchargeAmount);
                    Total(column, "Gross Tax Liability", data.GrossTaxLiability);

                    Line(column, "Less: APIT Credit", -data.ApitCredit);
                    Line(column, "Less: WHT Credit", -data.WhtCredit);
                    Line(column, "Less: Quarterly Tax Payments", -data.QuarterlyTaxPayments);

                    column.Item().PaddingTop(10).LineHorizontal(1.5f);
                    column.Item().Row(r =>
                    {
                        var label = data.BalanceTaxPayable < 0 ? "BALANCE TAX REFUNDABLE" : "BALANCE TAX PAYABLE";
                        r.RelativeItem(4).Text(label).Bold();
                        r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(data.BalanceTaxPayable)).Bold();
                    });
                });
            });
        }

        private static void Line(ColumnDescriptor column, string label, decimal amount)
        {
            column.Item().Row(r =>
            {
                r.RelativeItem(4).Text(label);
                r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(amount));
            });
        }

        private static void Total(ColumnDescriptor column, string label, decimal amount)
        {
            column.Item().PaddingTop(3).LineHorizontal(1);
            column.Item().Row(r =>
            {
                r.RelativeItem(4).Text(label).Bold();
                r.RelativeItem(1).AlignRight().Text(PdfFormatting.FormatAmount(amount)).Bold();
            });
            column.Item().PaddingTop(5);
        }
    }
}