using System.Collections.Generic;
using CSMath;
using OpenNest.Geometry;
using OpenNest.IO;
using Xunit;

namespace OpenNest.Tests.IO
{
    public class TitleBlockDetectorTests
    {
        private static Line MakeLine(double x1, double y1, double x2, double y2) =>
            new Line(x1, y1, x2, y2);

        [Fact]
        public void DetectByLayerName_FlagsTitleLayer()
        {
            var line = MakeLine(0, 0, 10, 0);
            line.Layer = new Layer("TITLE");
            var entities = new List<Entity> { line };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Contains(line.Id, result);
        }

        [Fact]
        public void DetectByLayerName_CaseInsensitive()
        {
            var line = MakeLine(0, 0, 10, 0);
            line.Layer = new Layer("border");
            var entities = new List<Entity> { line };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Contains(line.Id, result);
        }

        [Fact]
        public void DetectByLayerName_IgnoresNonMatchingLayers()
        {
            var line = MakeLine(0, 0, 10, 0);
            line.Layer = new Layer("0");
            var entities = new List<Entity> { line };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.DoesNotContain(line.Id, result);
        }

        [Theory]
        [InlineData("TITLE")]
        [InlineData("TITLEBLOCK")]
        [InlineData("TITLE_BLOCK")]
        [InlineData("BORDER")]
        [InlineData("FRAME")]
        [InlineData("TB")]
        [InlineData("INFO")]
        [InlineData("SHEET")]
        [InlineData("ANNOTATION")]
        public void DetectByLayerName_AllKnownNames(string layerName)
        {
            var line = MakeLine(0, 0, 10, 0);
            line.Layer = new Layer(layerName);
            var entities = new List<Entity> { line };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Contains(line.Id, result);
        }

        [Fact]
        public void DetectBorder_FlagsLinesOnBoundingBoxEdges()
        {
            var entities = new List<Entity>
            {
                new Line(0, 0, 86, 0) { Layer = new Layer("0") },
                new Line(86, 0, 86, 134) { Layer = new Layer("0") },
                new Line(86, 134, 0, 134) { Layer = new Layer("0") },
                new Line(0, 134, 0, 0) { Layer = new Layer("0") },
                new Line(30, 40, 50, 90) { Layer = new Layer("0") },
                new Line(50, 90, 70, 40) { Layer = new Layer("0") },
                new Line(70, 40, 30, 40) { Layer = new Layer("0") },
            };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Contains(entities[0].Id, result);
            Assert.Contains(entities[1].Id, result);
            Assert.Contains(entities[2].Id, result);
            Assert.Contains(entities[3].Id, result);
            Assert.DoesNotContain(entities[4].Id, result);
            Assert.DoesNotContain(entities[5].Id, result);
            Assert.DoesNotContain(entities[6].Id, result);
        }

        [Fact]
        public void DetectBorder_FlagsZoneMarkerTicks()
        {
            var entities = new List<Entity>
            {
                new Line(0, 0, 100, 0) { Layer = new Layer("0") },
                new Line(100, 0, 100, 80) { Layer = new Layer("0") },
                new Line(100, 80, 0, 80) { Layer = new Layer("0") },
                new Line(0, 80, 0, 0) { Layer = new Layer("0") },
                new Line(25, 80, 25, 77) { Layer = new Layer("0") },
                new Line(50, 80, 50, 77) { Layer = new Layer("0") },
                new Line(75, 80, 75, 77) { Layer = new Layer("0") },
                new Line(40, 30, 60, 30) { Layer = new Layer("0") },
            };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Contains(entities[4].Id, result);
            Assert.Contains(entities[5].Id, result);
            Assert.Contains(entities[6].Id, result);
            Assert.DoesNotContain(entities[7].Id, result);
        }

        [Fact]
        public void DetectBorder_IgnoresWhenNoBorderPresent()
        {
            var entities = new List<Entity>
            {
                new Line(30, 40, 50, 90) { Layer = new Layer("0") },
                new Line(50, 90, 70, 40) { Layer = new Layer("0") },
                new Line(70, 40, 30, 40) { Layer = new Layer("0") },
            };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Empty(result);
        }

        [Fact]
        public void DetectBorder_ToleratesSlightRotation()
        {
            var angleRad = OpenNest.Math.Angle.ToRadians(0.5);
            var endY = 86 * System.Math.Sin(angleRad);
            var entities = new List<Entity>
            {
                new Line(0, 0, 86, endY) { Layer = new Layer("0") },
                new Line(86, endY, 86, 134) { Layer = new Layer("0") },
                new Line(86, 134, 0, 134) { Layer = new Layer("0") },
                new Line(0, 134, 0, 0) { Layer = new Layer("0") },
                new Line(30, 40, 50, 90) { Layer = new Layer("0") },
            };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Contains(entities[0].Id, result);
        }

        [Fact]
        public void DetectTitleBlock_FlagsEntitiesInTextDenseCorner()
        {
            var partLine1 = new Line(5, 70, 25, 120) { Layer = new Layer("0") };
            var partLine2 = new Line(25, 120, 45, 70) { Layer = new Layer("0") };
            var partLine3 = new Line(45, 70, 5, 70) { Layer = new Layer("0") };

            var tbLines = new List<Entity>();
            for (var x = 50; x <= 85; x += 5)
                tbLines.Add(new Line(x, 0, x, 30) { Layer = new Layer("0") });
            for (var y = 0; y <= 30; y += 5)
                tbLines.Add(new Line(50, y, 85, y) { Layer = new Layer("0") });

            var entities = new List<Entity> { partLine1, partLine2, partLine3 };
            entities.AddRange(tbLines);

            var doc = BuildDocWithTexts(
                (60, 5, "TITLE: Test Part"),
                (60, 10, "DWG NO: 12345"),
                (60, 15, "SCALE: 1:1"),
                (60, 20, "REV: A"),
                (60, 25, "MATERIAL: STEEL"));

            var result = TitleBlockDetector.Detect(entities, doc);

            foreach (var tb in tbLines)
                Assert.Contains(tb.Id, result);
            Assert.DoesNotContain(partLine1.Id, result);
            Assert.DoesNotContain(partLine2.Id, result);
            Assert.DoesNotContain(partLine3.Id, result);
        }

        [Fact]
        public void DetectTitleBlock_NoFalsePositivesWithoutText()
        {
            var entities = new List<Entity>
            {
                new Line(30, 40, 50, 90) { Layer = new Layer("0") },
                new Line(50, 90, 70, 40) { Layer = new Layer("0") },
                new Line(70, 40, 30, 40) { Layer = new Layer("0") },
            };

            var result = TitleBlockDetector.Detect(entities, null);

            Assert.Empty(result);
        }

        [Fact]
        public void DetectTitleBlock_BottomEdgeStrip()
        {
            var partLine = new Line(20, 40, 80, 40) { Layer = new Layer("0") };

            var tbLines = new List<Entity>();
            for (var x = 0; x <= 100; x += 10)
                tbLines.Add(new Line(x, 0, x, 20) { Layer = new Layer("0") });
            for (var y = 0; y <= 20; y += 5)
                tbLines.Add(new Line(0, y, 100, y) { Layer = new Layer("0") });

            var entities = new List<Entity> { partLine };
            entities.AddRange(tbLines);

            var doc = BuildDocWithTexts(
                (10, 5, "TITLE"),
                (30, 5, "DWG NO"),
                (50, 5, "SCALE"),
                (70, 5, "REV"),
                (90, 5, "DATE"));

            var result = TitleBlockDetector.Detect(entities, doc);

            foreach (var tb in tbLines)
                Assert.Contains(tb.Id, result);
            Assert.DoesNotContain(partLine.Id, result);
        }

        private static ACadSharp.CadDocument BuildDocWithTexts(
            params (double x, double y, string value)[] texts)
        {
            var doc = new ACadSharp.CadDocument();
            foreach (var (x, y, value) in texts)
            {
                var mtext = new ACadSharp.Entities.MText
                {
                    InsertPoint = new XYZ(x, y, 0),
                    Value = value,
                    Height = 2.0
                };
                doc.Entities.Add(mtext);
            }
            return doc;
        }
    }
}