using System;
using System.IO;
using System.Linq;
using System.Xml;
using SBRL.Utilities;

namespace MusicBoxConverter
{
	public class Rectangle
	{
		public Vector2 Start { get; set; }
		public Vector2 Size { get; set; }

		public Rectangle(Vector2 inStart, Vector2 inSize)
		{
			Start = inStart;
			Size = inSize;
		}
	}

	/// <summary>
	/// TODO: Replace this with the (much) better version from the FloatingIslands
	/// </summary>
	public class SvgWriter
	{
		public XmlWriter xml;

		public string UnitSuffix { get; set; } = "";

		public SvgWriter(string outputFilename, string widthspec = "100%", string heightspec = "100%", Rectangle viewBox = null)
		{
			xml = XmlWriter.Create(
				outputFilename,
				new XmlWriterSettings() { Indent = true }
			);

			xml.WriteStartDocument();
			xml.WriteDocType("svg", "-//W3C//DTD SVG 1.1//EN", "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd", null);
			xml.WriteStartElement("svg", "http://www.w3.org/2000/svg");
			xml.WriteAttributeString("version", "1.1");
			xml.WriteAttributeString("x", "0");
			xml.WriteAttributeString("y", "0");
			xml.WriteAttributeString("width", widthspec);
			xml.WriteAttributeString("height", heightspec);
			if(viewBox != null) {
				xml.WriteAttributeString(
					"viewBox",
					$"{viewBox.Start.X} {viewBox.Start.Y} {viewBox.Size.X} {viewBox.Size.Y}"
				);
			}
		}

		public void Complete()
		{
			xml.WriteEndElement();
			xml.WriteEndDocument();
			xml.Close();
		}

		public void WriteLine(Vector2 start, Vector2 end, string strokeStyle = "darkgreen", float strokeWidth = 3)
		{
			xml.WriteStartElement("line");
			xml.WriteAttributeString("x1", $"{start.X}{UnitSuffix}");
			xml.WriteAttributeString("y1", $"{start.Y}{UnitSuffix}");
			xml.WriteAttributeString("x2", $"{end.X}{UnitSuffix}");
			xml.WriteAttributeString("y2", $"{end.Y}{UnitSuffix}");
			xml.WriteAttributeString("stroke", strokeStyle);
			xml.WriteAttributeString("stroke-width", strokeWidth.ToString());
			xml.WriteEndElement();
		}

		public void WritePolyLine(string strokeStyle, float strokeWidth, params Vector2[] points)
		{
			xml.WriteStartElement("polyline");
			xml.WriteAttributeString("points", string.Join(" ", points.Select((Vector2 p) => $"{p.X},{p.Y}")));
			xml.WriteAttributeString("stroke", strokeStyle);
			xml.WriteAttributeString("stroke-width", strokeWidth.ToString());
			xml.WriteAttributeString("fill", "none");
			xml.WriteEndElement();
		}

		/// <summary>
		/// Adds a cross centred on a point.
		/// </summary>
		/// <param name="centre">The centre of the cross.</param>
		/// <param name="radius">The radius of the cross.</param>
		/// <param name="strokeStyle">The stroke style to draw with.</param>
		/// <param name="strokeWidth">The stroke width to draw with.</param>
		public void WriteCross(Vector2 centre, Vector2 radius, string strokeStyle = "red", float strokeWidth = 1)
		{
			WriteLine(
				centre.Subtract(new Vector2(radius.X, radius.Y)),
				centre.Add(new Vector2(radius.X, radius.Y)),
				strokeStyle,
				strokeWidth
			);
			WriteLine(
				centre.Subtract(new Vector2(radius.X, -radius.Y)),
				centre.Add(new Vector2(radius.X, -radius.Y)),
				strokeStyle,
				strokeWidth
			);

		}

		public void StartScaleTransform(float scale)
		{
			xml.WriteStartElement("g");
			xml.WriteAttributeString("transform", $"scale({scale})");
		}
		public void EndTransform()
		{
			xml.WriteEndElement();
		}

		/*public void WritePath(string pathData, string strokeStyle = "green", int strokeWidth = 3)
		{
			xml.WriteStartElement("path");
			xml.WriteAttributeString("d", pathData);
			xml.WriteAttributeString("stroke", strokeStyle);
			xml.WriteAttributeString("stroke-width", strokeWidth.ToString());
			xml.WriteAttributeString("fill", "transparent");
			xml.WriteEndElement();
		}*/

		public void WriteRectangle(Vector2 position, Vector2 size, string strokeStyle = "red", float strokeWidth = 3, bool fillInstead = false)
		{
			xml.WriteStartElement("rect");
			xml.WriteAttributeString("x", $"{position.X}{UnitSuffix}");
			xml.WriteAttributeString("y", $"{position.Y}{UnitSuffix}");
			xml.WriteAttributeString("width", $"{size.X}{UnitSuffix}");
			xml.WriteAttributeString("height", $"{size.Y}{UnitSuffix}");
			if (!fillInstead) {
				xml.WriteAttributeString("fill", "none");
				xml.WriteAttributeString("stroke", strokeStyle);
				xml.WriteAttributeString("stroke-width", strokeWidth.ToString());
			}
			else
				xml.WriteAttributeString("fill", strokeStyle);
			xml.WriteEndElement();
		}
		public void WriteCircle(Vector2 centre, float radius, string fillStyle = "blue")
		{
			xml.WriteStartElement("circle");
			xml.WriteAttributeString("cx", $"{centre.X}{UnitSuffix}");
			xml.WriteAttributeString("cy", $"{centre.Y}{UnitSuffix}");
			xml.WriteAttributeString("r", $"{radius}{UnitSuffix}");
			xml.WriteAttributeString("fill", fillStyle);
			xml.WriteEndElement();
		}

		public void WriteText(Vector2 position, string text, float size = 12)
		{
			xml.WriteStartElement("text");
			xml.WriteAttributeString("x", $"{position.X}{UnitSuffix}");
			xml.WriteAttributeString("y", $"{position.Y}{UnitSuffix}");
			xml.WriteAttributeString("style", $"font-size: {size}{UnitSuffix}");
			xml.WriteValue(text);
			xml.WriteEndElement();
		}
	}
}