using DocumentService.Application.AddAnnotation;
using DocumentService.Application.AddStamp;
using DocumentService.Application.ConvertToPdfA;
using DocumentService.Application.MergePdfs;
using DocumentService.Domain.Models.ValueObjects;
using FluentAssertions;
using FluentValidation;
using FluentValidation.TestHelper;
using Xunit;

namespace DocumentService.Tests.Unit.Application.Validators;

// ─── MergePdfsCommandValidator ────────────────────────────────────────────────

public class MergePdfsCommandValidatorTests
{
    private readonly MergePdfsCommandValidator _validator = new();

    [Fact]
    public void Validate_TwoOrMoreStreams_PassesValidation()
    {
        var cmd = new MergePdfsCommand
        {
            PdfStreams = [new MemoryStream(), new MemoryStream()]
        };
        _validator.TestValidate(cmd).ShouldNotHaveAnyValidationErrors();
    }

    [Fact]
    public void Validate_SingleStream_FailsValidation()
    {
        var cmd = new MergePdfsCommand { PdfStreams = [new MemoryStream()] };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.PdfStreams);
    }

    [Fact]
    public void Validate_NullStreams_FailsValidation()
    {
        var cmd = new MergePdfsCommand { PdfStreams = null! };
        var result = _validator.TestValidate(cmd);
        result.Errors.Should().NotBeEmpty();
    }
}

// ─── AddAnnotationValidator ───────────────────────────────────────────────────

public class AddAnnotationValidatorTests
{
    private readonly AddAnnotationValidator _validator = new();

    [Fact]
    public void Validate_ValidCircleAnnotation_PassesValidation()
    {
        var cmd = new AddAnnotationCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            AnnotationType = AnnotationType.Circle,
            PageNumber = 1,
            Rectangle = (10, 20, 200, 100)
        };
        _validator.TestValidate(cmd).ShouldNotHaveAnyValidationErrors();
    }

    [Fact]
    public void Validate_FreeTextWithoutContent_FailsValidation()
    {
        var cmd = new AddAnnotationCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            AnnotationType = AnnotationType.FreeText,
            PageNumber = 1,
            Rectangle = (0, 0, 100, 50),
            Content = null
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.Content);
    }

    [Fact]
    public void Validate_TextMarkupWithoutStyle_FailsValidation()
    {
        var cmd = new AddAnnotationCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            AnnotationType = AnnotationType.TextMarkup,
            PageNumber = 1,
            Rectangle = (0, 0, 100, 50),
            TextMarkupStyle = null
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.TextMarkupStyle);
    }

    [Fact]
    public void Validate_InvalidColorFormat_FailsValidation()
    {
        var cmd = new AddAnnotationCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            AnnotationType = AnnotationType.Circle,
            PageNumber = 1,
            Rectangle = (0, 0, 100, 50),
            Color = "GGGGGG" // invalid hex
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.Color);
    }

    [Fact]
    public void Validate_ValidColorFormat_PassesValidation()
    {
        var cmd = new AddAnnotationCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            AnnotationType = AnnotationType.Circle,
            PageNumber = 1,
            Rectangle = (0, 0, 100, 50),
            Color = "FF0000"
        };
        _validator.TestValidate(cmd).ShouldNotHaveAnyValidationErrors();
    }

    [Fact]
    public void Validate_ZeroPageNumber_FailsValidation()
    {
        var cmd = new AddAnnotationCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            AnnotationType = AnnotationType.Circle,
            PageNumber = 0,
            Rectangle = (0, 0, 100, 50)
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.PageNumber);
    }

    [Fact]
    public void Validate_InvalidRectangle_FailsValidation()
    {
        var cmd = new AddAnnotationCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            AnnotationType = AnnotationType.Circle,
            PageNumber = 1,
            Rectangle = (100, 100, 50, 50) // X2 < X1
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.Rectangle);
    }
}

// ─── AddStampValidator ────────────────────────────────────────────────────────

public class AddStampValidatorTests
{
    private readonly AddStampValidator _validator = new();

    [Fact]
    public void Validate_ValidTextStamp_PassesValidation()
    {
        var cmd = new AddStampCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            StampType = StampType.Text,
            Position = (100, 200),
            Text = "DRAFT"
        };
        _validator.TestValidate(cmd).ShouldNotHaveAnyValidationErrors();
    }

    [Fact]
    public void Validate_TextStampWithoutText_FailsValidation()
    {
        var cmd = new AddStampCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            StampType = StampType.Text,
            Position = (100, 200),
            Text = null
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.Text);
    }

    [Fact]
    public void Validate_ImageStampWithoutBytes_FailsValidation()
    {
        var cmd = new AddStampCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            StampType = StampType.Image,
            Position = (0, 0),
            ImageBytes = null
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.ImageBytes);
    }

    [Fact]
    public void Validate_PredefinedStampWithoutType_FailsValidation()
    {
        var cmd = new AddStampCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            StampType = StampType.Predefined,
            Position = (0, 0),
            PredefinedType = null
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.PredefinedType);
    }

    [Fact]
    public void Validate_OpacityAboveOne_FailsValidation()
    {
        var cmd = new AddStampCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            StampType = StampType.Text,
            Position = (0, 0),
            Text = "TEST",
            Opacity = 1.5
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.Opacity!.Value);
    }

    [Fact]
    public void Validate_InvalidColorHex_FailsValidation()
    {
        var cmd = new AddStampCommand
        {
            PdfStream = new MemoryStream("%PDF"u8.ToArray()),
            StampType = StampType.Text,
            Position = (0, 0),
            Text = "TEST",
            Color = "XYZ"
        };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.Color!);
    }
}

// ─── ConvertToPdfACommandValidator ───────────────────────────────────────────

public class ConvertToPdfAValidatorTests
{
    private readonly ConvertToPdfACommandValidator _validator = new();

    [Fact]
    public void Validate_ValidPdfALevel_PassesValidation()
    {
        foreach (var level in new[] { "PDF/A-1b", "PDF/A-2b", "PDF/A-3b", "PDF/A-3u" })
        {
            var cmd = new ConvertToPdfACommand { PdfStream = new MemoryStream(), PdfALevel = level };
            _validator.TestValidate(cmd).ShouldNotHaveAnyValidationErrors();
        }
    }

    [Fact]
    public void Validate_InvalidPdfALevel_FailsValidation()
    {
        var cmd = new ConvertToPdfACommand { PdfStream = new MemoryStream(), PdfALevel = "PDF/A-99z" };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.PdfALevel);
    }

    [Fact]
    public void Validate_EmptyPdfALevel_FailsValidation()
    {
        var cmd = new ConvertToPdfACommand { PdfStream = new MemoryStream(), PdfALevel = "" };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.PdfALevel);
    }

    [Fact]
    public void Validate_NullStream_FailsValidation()
    {
        var cmd = new ConvertToPdfACommand { PdfStream = null!, PdfALevel = "PDF/A-1b" };
        _validator.TestValidate(cmd).ShouldHaveValidationErrorFor(x => x.PdfStream);
    }
}