using LehrerApp.TemplateDesigner;
using LehrerApp.Templating;
using Xunit;
using System.Runtime.Versioning;
using QuestPDF.Fluent;
using QuestPDF.Infrastructure;

namespace LehrerApp.TemplateDesigner.Tests;

[SupportedOSPlatform("windows")]
[SupportedOSPlatform("linux")]
[SupportedOSPlatform("macos")]
public sealed class PdfImportPipelineTests
{
    [Fact]
    public void TemplateDiff_LaesstIdentischenTextStatischUndMarkiertAbweichung()
    {
        var pipeline = new PdfImportPipeline();
        var template = Document(
            Block("a", 40, 30, "Schule am Park"),
            Block("b", 40, 100, "Max Mustermann"));
        var example = Document(
            Block("a2", 40, 30, "Schule am Park"),
            Block("b2", 40, 100, "Erika Beispiel"));

        var candidate = Assert.Single(pipeline.FindCandidates(example, template));

        Assert.Equal("Erika Beispiel", candidate.OriginalText);
        Assert.Equal(PdfImportConfidence.High, candidate.Confidence);
    }

    [Fact]
    public void EinzelPdf_ErkenntDatumTypDeterministisch()
    {
        var pipeline = new PdfImportPipeline();

        var candidate = Assert.Single(pipeline.FindCandidates(Document(Block("d", 400, 60, "31.08.2026")), null));

        Assert.Equal("Datum", candidate.Name);
        Assert.Equal(PlaceholderType.Date, candidate.Type);
        Assert.Equal(PdfImportConfidence.High, candidate.Confidence);
    }

    [Fact]
    public void UebernahmeErsetztDasAktuelleDesignerprojekt()
    {
        var result = new PdfImportResult("PAGE 595 842 pt\nTEXT 40 100 $Name\n",
            new TemplateManifest
            {
                Id = "pdf-import", Name = "PDF-Import", PageSize = new(595, 842, "pt"),
                Placeholders = [new("Name", PlaceholderType.Text)],
            }, new Dictionary<string, byte[]>(),
            [new PdfImportCandidate { Id = "x", BlockIds = ["x"], OriginalText = "Erika Beispiel", Name = "Name", Confidence = PdfImportConfidence.High }]);
        var viewModel = new DesignerViewModel();

        viewModel.ApplyPdfImport(result);

        Assert.Equal("pt", viewModel.Unit);
        Assert.Equal("Erika Beispiel", Assert.Single(viewModel.Placeholders).Sample);
        Assert.Contains("$Name", viewModel.LayoutSource);
        Assert.False(viewModel.CanExport);
    }

    [Fact]
    public async Task EchtesPdf_WirdExtrahiertUndAlsRenderbareVorlageErzeugt()
    {
        QuestPDF.Settings.License = LicenseType.Community;
        var path = Path.Combine(Path.GetTempPath(), $"pdf-import-{Guid.NewGuid():N}.pdf");
        try
        {
            QuestPDF.Fluent.Document.Create(document => document.Page(page =>
            {
                page.Size(595, 842); page.Margin(40); page.Content().Text("Erika Beispiel").FontSize(11);
            })).GeneratePdf(path);

            var result = await new PdfImportPipeline().BuildAsync(path, null, null, null);
            var viewModel = new DesignerViewModel();
            viewModel.ApplyPdfImport(result);
            var png = new QuestTemplateRenderer().RenderFirstPageToPng(viewModel.BuildLoaded(), viewModel.BuildDataProvider());

            Assert.NotEmpty(result.Candidates);
            Assert.Contains("pdf-import-background.png", result.Assets.Keys);
            Assert.True(png.Length > 1_000);
        }
        finally { if (File.Exists(path)) File.Delete(path); }
    }

    private static PdfImportDocument Document(params PdfTextBlock[] blocks) =>
        new([new PdfImportPage(1, 595, 842, blocks)]);

    private static PdfTextBlock Block(string id, double x, double y, string text) =>
        new(id, 1, x, y, 120, 12, 11, "Arial", false, false, text);
}