//	Spludlow Software
//	Copyright © Samuel P. Ludlow 2020 All Rights Reserved
//	Distributed under the terms of the GNU General Public License version 3
//	Distributed WITHOUT ANY WARRANTY; without implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE
//	https://www.spludlow.co.uk/LICENCE.TXT
//	The Spludlow logo is a registered trademark of Samuel P. Ludlow and may not be used without permission
//	v1.14

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

using System.IO;
using System.Drawing;
using System.Drawing.Imaging;
using System.Data;

namespace Spludlow.Drawing
{
	public class ThumbNails
	{
		List<string> SupportedExtentions;
		private string RootFilePath;
		private string RootWebPath;
		private Size BoxSize;
		private int Dpi;

		public ThumbNails(string configKey)
		{
			string config = Spludlow.Config.Get(configKey);
			string[] words = Spludlow.Text.Split(config, ',', true);
			if (words.Length != 5)
				throw new ApplicationException("Thumbs; Config Format 'FilePath, WebPath, Width, Height, DPI' :\t" + config);

			this.Setup(words[0], words[1], Int32.Parse(words[2]), Int32.Parse(words[3]), Int32.Parse(words[4]));
		}

		public ThumbNails(string rootFilePath, string rootWebPath, int width, int height)
		{
			this.Setup(rootFilePath, rootWebPath, width, height, 72);
		}

		public ThumbNails(string rootFilePath, string rootWebPath, int width, int height, int dpi)
		{
			this.Setup(rootFilePath, rootWebPath, width, height, dpi);
		}

		private void Setup(string rootFilePath, string rootWebPath, int width, int height, int dpi)
		{
			this.SupportedExtentions = new List<string>(new string[]
			{
				".jpg", ".jpeg", ".png", ".bmp", ".tif", ".tiff", ".gif",
			});

			this.RootFilePath = this.TrimTrailing(rootFilePath, '\\');
			this.RootWebPath = this.TrimTrailing(rootWebPath, '/');

			this.BoxSize = new Size(width, height);
			this.Dpi = 72;

			//if (Directory.Exists(this.RootFilePath) == false)
			//	throw new ApplicationException("ThumbNails; Root Directory not there:\t" + this.RootFilePath);
		}

		private string TrimTrailing(string text, char trimChar)
		{
			while (text[text.Length - 1] == trimChar)
				text = text.Substring(0, text.Length - 1);

			return text;
		}

		public void AddPaths(DataTable table, string sourceFilenameColumnName, string targetWebPathColumnName, string targetFilePathColumnName, bool write)
		{
			foreach (DataRow row in table.Rows)
			{
				string sourceFilename = (string)row[sourceFilenameColumnName];
				string[] webAndFilePath = this.WebAndFilePath(sourceFilename, write);

				if (targetWebPathColumnName != null)
					row[targetWebPathColumnName] = webAndFilePath[0];

				if (targetFilePathColumnName != null)
					row[targetFilePathColumnName] = webAndFilePath[1];
			}
		}

		public string[] WebAndFilePath(string sourceFilename, bool write)
		{
			string extention = Path.GetExtension(sourceFilename).ToLower();

			StringBuilder resultFile = new StringBuilder();
			resultFile.Append(this.RootFilePath);

			StringBuilder resultWeb = new StringBuilder();
			resultWeb.Append(this.RootWebPath);

			if (this.SupportedExtentions.Contains(extention) == false)
			{
				resultFile.Append('\\');
				resultWeb.Append('/');

				string blankName = this.BoxSize.Width + "X" + this.BoxSize.Height + "-" + this.Dpi + extention + ".jpg";

				resultFile.Append(blankName);
				resultWeb.Append(blankName);

				string blankFilename = resultFile.ToString();
				string blankWebPath = resultWeb.ToString();

				if (write == true && File.Exists(blankFilename) == false)
					this.MakeBlank(blankFilename, Color.LawnGreen, extention);

				return new string[] { blankWebPath, null };		//	blankFilename		never return path to a special as dont want to ever delete
			}

			string[] directoryParts = Path.GetDirectoryName(sourceFilename).Split(new char[] { '\\' }, StringSplitOptions.RemoveEmptyEntries);	//	Don't need to do??

			foreach (string rawPart in directoryParts)
			{
				resultFile.Append('\\');
				resultWeb.Append('/');

				string part = rawPart;
				if (part.Length == 2 && part[1] == ':')
					part = part.Substring(0, 1);

				resultFile.Append(part);
				resultWeb.Append(part);

				if (write == true)
				{
					string directory = resultFile.ToString();
					if (Directory.Exists(directory) == false)
						Directory.CreateDirectory(directory);
				}
			}

			resultFile.Append("\\");
			resultWeb.Append('/');

			string name = Path.GetFileNameWithoutExtension(sourceFilename) + ".jpg";

			resultFile.Append(name);
			resultWeb.Append(name);

			string thumbFilename = resultFile.ToString();
			string webPath = resultWeb.ToString();

			if (write == true && File.Exists(thumbFilename) == false)
			{
				try
				{
					Spludlow.Drawing.Bitmaps.Resize(sourceFilename, this.BoxSize, thumbFilename, ImageFormat.Jpeg, PixelFormat.Format24bppRgb, this.Dpi);
				}
				catch (Exception ee)
				{
					Spludlow.Log.Error("ThumbNails; Resize source:" + sourceFilename + ", thumb:" + thumbFilename, ee);
				}
			}

			return new string[] { webPath, thumbFilename };
		}

		private void MakeBlank(string filename, Color colour, string extention)
		{
			using (Bitmap bitmap = new Bitmap(this.BoxSize.Width, this.BoxSize.Height, PixelFormat.Format24bppRgb))
			{
				bitmap.SetResolution(this.Dpi, this.Dpi);

				using (Graphics graphics = Graphics.FromImage(bitmap))
					graphics.Clear(colour);

				bitmap.Save(filename, ImageFormat.Jpeg);
			}
		}

	}
}