//	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.Data;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;

namespace Spludlow
{
	/// <summary>
	/// Provide a simple web menu
	/// Configured through App_Data/Pages.txt
	/// Looks for Literal on master page and sets it to a HTML table
	/// Works for indefinate levels
	/// Can also set page meta data
	/// </summary>
	public class WebMenu
	{
		public static void PageLoad(MasterPage masterPage, string webKey)
		{
			PageLoad(masterPage, webKey, "width:100%;");
		}
		public static void PageLoad(MasterPage masterPage, string webKey, string tableStyle)
		{
			webKey = "Spludlow.WebMenu." + webKey;

			DataSet dataSet = LoadData(webKey);

			DataTable pagesTable = dataSet.Tables["Pages"];

			Literal literalMenuDebug = (Literal)masterPage.FindControl("LiteralMenuDebug");

			Literal literalMenu = (Literal)masterPage.FindControl("LiteralMenu");

			Literal literalContents = (Literal)Spludlow.WebControls.Find("LiteralSectionContents", masterPage);

			int length = masterPage.Request.ApplicationPath.Length;
			if (length == 1)
				length = 0;
			string pageUrl = masterPage.Request.Url.PathAndQuery.Substring(length);

			int index = pageUrl.IndexOf("?");
			if (index != -1)
				pageUrl = pageUrl.Substring(0, index);

			DataRow pageRow = pagesTable.Rows.Find(pageUrl);


			string pageTitle = null;
			if (pageRow != null && pageRow.IsNull("PageTitle") == false)
				pageTitle = (string)pageRow["PageTitle"];

			DisplayHeadFoot(masterPage, pageTitle);

			if (pageRow != null)
				DisplayMeta(masterPage, pageRow);


			bool pageNotInMenu = false;

			if (pageRow == null)
			{
				index = pageUrl.LastIndexOf("/");

				if (index != -1)
				{
					pageUrl = pageUrl.Substring(0, index) + "/Default.aspx";
					pageRow = pagesTable.Rows.Find(pageUrl);
				}
				
				pageNotInMenu = true;
			}

			if (pageRow != null)
			{
				int currentId = (int)pageRow["Id"];
				int currentParentId = (int)pageRow["ParentId"];
				int currentLevel = (int)pageRow["Level"];
				
				List<DataRow[]> menuRows = new List<DataRow[]>();   //	Reverse Level order

				List<int> currentIds = new List<int>();

				currentIds.Add(currentId);

				DataRow[] rows;

				if (currentParentId != 0)
				{
					rows = pagesTable.Select("ParentId = " + currentId);

					if (rows.Length > 0)    //	Below current
						menuRows.Add(rows);
				}

				int nextParentId = currentParentId;

				for (int level = currentLevel; level > 0; --level)
				{
					if (level == 1) //	Always all
					{
						rows = pagesTable.Select("Level = 1");
					}
					else
					{
						rows = pagesTable.Select("ParentId = " + nextParentId);

						currentIds.Add(nextParentId);

						DataRow[] tempRows = pagesTable.Select("Id = " + nextParentId);
						nextParentId = (int)tempRows[0]["ParentId"];
					}

					menuRows.Add(rows);
				}

				if (pageNotInMenu == true && pageUrl == "/Default.aspx")
					currentIds.Clear();

				//literalMenuDebug.Text = pageUrl + " # " + currentId + "selected: ";

				//foreach (int id in currentIds)
				//	literalMenuDebug.Text += id + ", ";


				StringBuilder text = new StringBuilder();

				for (int levelIndex = menuRows.Count - 1; levelIndex >= 0; --levelIndex)
				{
					rows = menuRows[levelIndex];

					if (tableStyle != "")
					{
						text.AppendLine("<table style=\"");
						text.AppendLine(tableStyle);
						text.AppendLine("\"><tr>");
					}
					else
					{
						text.AppendLine("<table><tr>");
					}


					foreach (DataRow levelRow in rows)
					{
						string styleClass = "M0";
						if (currentIds.Contains((int)levelRow["Id"]) == true)
						{
							styleClass = "M1";
						}

						string title = "";

						if (levelRow.IsNull("PageTitle") == false)
							title = (string)levelRow["PageTitle"];

						if (levelRow.IsNull("PageDescription") == false)
							title = title + " " + Environment.NewLine + " " + (string)levelRow["PageDescription"];

						text.Append("<td class=\"");
						text.Append(styleClass);
						text.Append("\">");

						text.Append("<a href=\"");
						text.Append(masterPage.Page.ResolveUrl("~" + LinkPageUrl((string)levelRow["PageUrl"])));
						text.Append("\" title=\"");
						text.Append(title);
						text.Append("\" class=\"");
						text.Append(styleClass);
						text.Append("\" >");
						text.Append((string)levelRow["MenuTitle"]);
						text.Append("</a>");

						text.Append("</td>");
						text.AppendLine();
					}

					text.AppendLine("</tr></table>");
				}

				literalMenu.Text = text.ToString();

				if (literalContents != null && menuRows.Count > 0)
				{
					text.Length = 0;

					rows = menuRows[0];

					text.Append("<h2>");

					string title = (string)pageRow["MenuTitle"];

					if (title == "Home")
						text.Append("Site Sections");
					else
						text.Append(title + " Section Contents");
					
					text.Append("</h2>");

					text.AppendLine("<table style=\"width:100%\">");
					foreach (DataRow row in rows)
					{
						text.AppendLine("<tr>");

						text.AppendLine("<td>");

						text.Append("<a href=\"");
						text.Append(masterPage.Page.ResolveUrl("~" + LinkPageUrl((string)row["PageUrl"])));
						text.Append("\" title=\"");
						if (row.IsNull("PageDescription") == false)
							text.Append((string)row["PageDescription"]);
						text.Append("\" >");
						text.Append((string)row["MenuTitle"]);
						text.Append("</a>");

						text.AppendLine("</td>");

						text.AppendLine("<td>");
						if (row.IsNull("PageTitle") == false)
							text.Append((string)row["PageTitle"]);
						text.AppendLine("</td>");

						text.AppendLine("</tr>");
					}
					text.AppendLine("</table>");

					text.AppendLine("<hr />");

					literalContents.Text = text.ToString();
				}

			}
			//else
			//{
			//	literalMenuDebug.Text = pageUrl + " # Page not found in table";
			//}

			
		}

		private static string LinkPageUrl(string url)
		{
			if (url.EndsWith("/Default.aspx") == true)
				url = url.Substring(0, url.Length - 12);
			return url;
		}

		private static void DisplayMeta(MasterPage masterPage, DataRow pageRow)
		{
			Literal literal;
			string text;

			if (pageRow.IsNull("PageDescription") == false)
			{
				text = (string)pageRow["PageDescription"];

				SetMetaHead(masterPage, "description", text);

				literal = (Literal)Spludlow.WebControls.Find("WebContentDescription", masterPage.Page);
				if (literal != null)
					literal.Text = text;
			}

			if (pageRow.IsNull("PageKeyWords") == false)
			{
				text = (string)pageRow["PageKeyWords"];

				SetMetaHead(masterPage, "keywords", text);

				literal = (Literal)Spludlow.WebControls.Find("LiteralWebContentKeyWords", masterPage.Page);
				if (literal != null)
					literal.Text = text;
			}
		}

		public static void SetMetaHead(MasterPage masterPage, string name, string content)
		{
			HtmlHead htmlHead = (HtmlHead)masterPage.Page.Header;
			HtmlMeta meta = new HtmlMeta();
			meta.Name = name;
			meta.Content = content;
			htmlHead.Controls.Add(meta);
		}

		private static void DisplayHeadFoot(MasterPage masterPage, string heading)
		{
			string pageHeading = GetLiteralText(masterPage, "MenuHead");
			if (pageHeading != null && pageHeading.Length > 0)
				heading = pageHeading;

			if (heading == null)
			{
				heading = masterPage.Request.Url.AbsolutePath;
				int index;
				index = heading.LastIndexOf("/");
				if (index != -1 && index != (heading.Length - 1))
					heading = heading.Substring(index + 1);
				index = heading.LastIndexOf(".");
				if (index != -1)
					heading = heading.Substring(0, index);
			}

			SetLiteralText(masterPage, "MenuHead", heading);

			masterPage.Page.Title = heading;
		}

		public static void SetLiteralText(MasterPage masterPage, string controlName, string text)
		{
			Literal control = (Literal)masterPage.FindControl(controlName);
			if (control == null)
				return;
			control.Text = text;
		}

		public static string GetLiteralText(MasterPage masterPage, string controlName)
		{
			Literal control = (Literal)masterPage.FindControl(controlName);
			if (control == null)
				return null;
			return control.Text;
		}

		private static DataSet LoadData(string webKey)
		{
			DataSet dataSet = (DataSet)Spludlow.Caching.Get(webKey);

			if (dataSet != null)
				return dataSet;

			dataSet = new DataSet();

			string webAppDataDirectory = Path.Combine(HttpContext.Current.Request.PhysicalApplicationPath, "App_Data");

			if (Directory.Exists(webAppDataDirectory) == false)
				Directory.CreateDirectory(webAppDataDirectory);

			string pagesFilename = webAppDataDirectory + @"\Pages.txt";

			if (File.Exists(pagesFilename) == false)
			{
				throw new ApplicationException(pagesFilename + " needs creating");
			}

			DataTable pagesTable = Spludlow.Data.TextTable.ReadFile(pagesFilename, true);

			//	MenuTitle				PageUrl										PageTitle								PageDescription											PageKeyWords

			DataTable table;

			table = Spludlow.Data.TextTable.ReadText(new string[]
			{
				"Id		ParentId	Level	MenuStyle",
				"Int32	Int32		Int32	String",
			});
			foreach (DataColumn column in pagesTable.Columns)
				table.Columns.Add(column.ColumnName, column.DataType);

			int id = 0;
			foreach (DataRow sourceRow in pagesTable.Rows)
			{
				table.ImportRow(sourceRow);

				DataRow row = table.Rows[table.Rows.Count - 1];

				row["Id"] = ++id;

				string pageUrl = (string)row["PageUrl"];
				if (pageUrl.EndsWith("/") == true)
					row["PageUrl"] = pageUrl += "Default.aspx";

				int level = 0;
				foreach (char ch in pageUrl)
				{
					if (ch == '/')
						++level;
				}
				if (pageUrl.EndsWith("/Default.aspx") == true)
					--level;

				if (level == 0)
				{
					level = 1;
					row["ParentId"] = 0;
				}
				row["Level"] = level;

				row["MenuStyle"] = "M" + level + "-0";	//	Not using still just M0 M1 at each level
			}
			pagesTable = table;

			pagesTable.PrimaryKey = new DataColumn[] { pagesTable.Columns["PageUrl"] };

			foreach (DataRow row in pagesTable.Rows)
			{
				string pageUrl = (string) row["PageUrl"];

				if (pageUrl != "/Default.aspx")
				{
					int index = pageUrl.LastIndexOf("/");
					if (pageUrl.EndsWith("/Default.aspx") == true)
						index = pageUrl.LastIndexOf("/", index - 1);

					if (index != -1)
					{
						string parentUrl = pageUrl.Substring(0, index) + "/Default.aspx";

						DataRow parentRow = pagesTable.Rows.Find(parentUrl);
						if (parentRow != null)
							row["ParentId"] = parentRow["Id"];
					}
				}
			}

			pagesTable.TableName = "Pages";
			dataSet.Tables.Add(pagesTable);

			Spludlow.Log.Report("Web Menu; Loaded", dataSet);

			Spludlow.Caching.Set(webKey, dataSet);

			return dataSet;
		}
	}
}