#nullable enable
using System;
using System.Collections.Generic;
using System.Globalization;
using System.IO;
using Microsoft.Build.Framework;
using SkiaSharp;
 
namespace Microsoft.Maui.Resizetizer
{
	internal class ResizeImageInfo
	{
		public string? ItemSpec { get; set; }
 
		public string? Alias { get; set; }
 
		public string? Filename { get; set; }
 
		public string OutputName =>
			string.IsNullOrWhiteSpace(Alias)
				? string.IsNullOrWhiteSpace(Filename)
					? Path.GetFileNameWithoutExtension(ForegroundFilename)
					: Path.GetFileNameWithoutExtension(Filename)
				: Path.GetFileNameWithoutExtension(Alias);
 
		public string OutputExtension =>
			string.IsNullOrWhiteSpace(Alias) || !Path.HasExtension(Alias)
				? string.IsNullOrWhiteSpace(Filename) || !Path.HasExtension(Filename)
					? Path.GetExtension(ForegroundFilename)
					: Path.GetExtension(Filename)
				: Path.GetExtension(Alias);
 
		public bool OutputIsVector => IsVectorExtension(OutputExtension);
 
		public SKSize? BaseSize { get; set; }
 
		public bool Resize { get; set; } = true;
 
		public SKColor? TintColor { get; set; }
 
		public SKColor? Color { get; set; }
 
		public bool IsVector => IsVectorFilename(Filename);
 
		public bool IsAppIcon { get; set; }
 
		public string? ForegroundFilename { get; set; }
 
		public bool ForegroundIsVector => IsVectorFilename(ForegroundFilename);
 
		public double ForegroundScale { get; set; } = 1.0;
 
		private static bool IsVectorFilename(string? filename)
			=> IsVectorExtension(Path.GetExtension(filename));
 
		private static bool IsVectorExtension(string? extension)
			=> extension?.Equals(".svg", StringComparison.OrdinalIgnoreCase) ?? false;
 
		public static List<ResizeImageInfo> Parse(IEnumerable<ITaskItem> images)
		{
			var r = new List<ResizeImageInfo>();
 
			if (images == null)
				return r;
 
			foreach (var image in images)
			{
				var info = Parse(image);
				r.Add(info);
			}
 
			return r;
		}
 
		public static ResizeImageInfo Parse(ITaskItem image)
		{
			var info = new ResizeImageInfo();
 
			info.ItemSpec = image.ItemSpec;
 
			var fileInfo = new FileInfo(image.GetMetadata("FullPath"));
			if (!fileInfo.Exists)
				throw new FileNotFoundException("Unable to find background file: " + fileInfo.FullName, fileInfo.FullName);
 
			info.Filename = fileInfo.FullName;
 
			info.Alias = image.GetMetadata("Link");
 
			info.BaseSize = Utils.ParseSizeString(image.GetMetadata("BaseSize"));
 
			if (bool.TryParse(image.GetMetadata("Resize"), out var rz))
			{
				info.Resize = rz;
			}
			else if (info.BaseSize == null && !info.IsVector)
			{
				// By default do not resize non-vector images
				info.Resize = false;
			}
 
			var tintColor = image.GetMetadata("TintColor");
			info.TintColor = Utils.ParseColorString(tintColor);
			if (info.TintColor is null && !string.IsNullOrEmpty(tintColor))
				throw new InvalidDataException($"Unable to parse color value '{tintColor}' for '{info.Filename}'.");
 
			var color = image.GetMetadata("Color");
			info.Color = Utils.ParseColorString(color);
			if (info.Color is null && !string.IsNullOrEmpty(color))
				throw new InvalidDataException($"Unable to parse color value '{color}' for '{info.Filename}'.");
 
			if (bool.TryParse(image.GetMetadata("IsAppIcon"), out var iai))
				info.IsAppIcon = iai;
 
			if (float.TryParse(image.GetMetadata("ForegroundScale"), NumberStyles.Number, CultureInfo.InvariantCulture, out var fsc))
				info.ForegroundScale = fsc;
 
			var fgFile = image.GetMetadata("ForegroundFile");
			if (!string.IsNullOrEmpty(fgFile))
			{
				var fgFileInfo = new FileInfo(fgFile);
				if (!fgFileInfo.Exists)
					throw new FileNotFoundException("Unable to find foreground file: " + fgFileInfo.FullName, fgFileInfo.FullName);
 
				info.ForegroundFilename = fgFileInfo.FullName;
			}
 
			// make sure the image is a foreground if this is an icon
			if (info.IsAppIcon && string.IsNullOrEmpty(info.ForegroundFilename))
			{
				info.ForegroundFilename = info.Filename;
				info.Filename = null;
			}
 
			// TODO:
			// - Parse out custom DPI's
 
			return info;
		}
	}
}