using System;
using System.Configuration;
using System.Configuration.Provider;
using Npgsql;
using System.Collections.Generic;
using Yavsc.Model.Blogs;

namespace Npgsql.Web.Blog
{
	/// <summary>
	/// Npgsql blog provider.
	/// </summary>
	public class NpgsqlBlogProvider : BlogProvider
	{
		string applicationName;
		string connectionString;

		#region implemented abstract members of BlogProvider
		/// <summary>
		/// Tag the specified postid and tag.
		/// </summary>
		/// <param name="postid">Postid.</param>
		/// <param name="tag">Tag.</param>
		public override long Tag (long postid, string tag)
		{
			using (NpgsqlConnection cnx = new NpgsqlConnection (connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand ()) {
				cmd.CommandText = "insert into bltag (blid,tag) values (@postid,@tag) returning _id";
				cmd.Parameters.AddWithValue("@tag",tag);
				cmd.Parameters.AddWithValue("@postid",postid);
				return (long) cmd.ExecuteScalar ();
			}
		}
		/// <summary>
		/// Removes the tag.
		/// </summary>
		/// <param name="tagid">Tagid.</param>
		public override void RemoveTag (long tagid)
		{
			using (NpgsqlConnection cnx = new NpgsqlConnection (connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand ()) {
				cmd.CommandText = "delete from bltag where _id = @tagid";
				cmd.Parameters.AddWithValue("@tagid",tagid);
				cmd.ExecuteNonQuery ();	
			}
		}
		/// <summary>
		/// Gets the post identifier.
		/// </summary>
		/// <returns>The post identifier.</returns>
		/// <param name="username">Username.</param>
		/// <param name="title">Title.</param>
		public override long GetPostId (string username, string title)
		{
			throw new NotImplementedException ();
		}
		/// <summary>
		/// Gets the comments.
		/// </summary>
		/// <returns>The comments.</returns>
		/// <param name="postid">Postid.</param>
		/// <param name="getHidden">If set to <c>true</c> get hidden.</param>
		public override Comment[] GetComments (long postid, bool getHidden)
		{
			List<Comment> cmts = new List<Comment> ();

			using (NpgsqlConnection cnx=new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {

				cmd.CommandText = "select _id, username, bcontent, modified, posted, visible from comment " +
				                  "where applicationname = @appname and postid = @id" + 
				                  ((getHidden) ?  " and visible = true ":" ") + 
				                  "order by posted asc" ;
				cmd.Parameters.AddWithValue ("@appname", applicationName);
				cmd.Parameters.AddWithValue ("@id", postid);
				cnx.Open ();
				using (NpgsqlDataReader rdr = cmd.ExecuteReader()) {
					while (rdr.Read ()) {
						Comment c = new Comment();
						c.CommentText = rdr.GetString (rdr.GetOrdinal ("bcontent"));
						c.From = rdr.GetString (rdr.GetOrdinal ("username"));
						c.Modified = rdr.GetDateTime (rdr.GetOrdinal ("modified"));
						c.Posted = rdr.GetDateTime (rdr.GetOrdinal ("posted"));
						c.Visible = rdr.GetBoolean (rdr.GetOrdinal ("visible"));
						c.PostId = postid;
						c.Id = rdr.GetInt64(rdr.GetOrdinal("_id"));
						cmts.Add (c);
					}
				}
			}
			return cmts.ToArray();
		}
		/// <summary>
		/// Updates the post.
		/// </summary>
		/// <param name="postid">Postid.</param>
		/// <param name="title">Title.</param>
		/// <param name="content">Content.</param>
		/// <param name="visible">If set to <c>true</c> visible.</param>
		public override void UpdatePost (long postid, string title, string content, bool visible)
		{
			using (NpgsqlConnection cnx = new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {
				DateTime now = DateTime.Now;
				cmd.CommandText = 
					"update blog set modified=@now," +
					" title = @title," +
					" bcontent=@content, " +
					" visible = @visible " +
					"where _id = @id";
				cmd.Parameters.AddWithValue ("@now", now);
				cmd.Parameters.AddWithValue ("@title", title);
				cmd.Parameters.AddWithValue ("@content", content);
				cmd.Parameters.AddWithValue ("@visible", visible);
				cmd.Parameters.AddWithValue ("@id", postid);
				cnx.Open ();
				cmd.ExecuteNonQuery ();
				cnx.Close();
			}
		}
		/// <summary>
		/// Removes the post.
		/// </summary>
		/// <param name="postid">Postid.</param>
		public override void RemovePost (long postid)
		{
			throw new NotImplementedException ();
		}
		/// <summary>
		/// Comment the specified from, postid and content.
		/// </summary>
		/// <param name="from">From.</param>
		/// <param name="postid">Postid.</param>
		/// <param name="content">Content.</param>
		public override long Comment (string from, long postid, string content)
		{
			if (from == null)
				throw new ArgumentNullException("from");
			if (content == null)
				throw new ArgumentNullException("content");
			bool visible = AutoValidateComment;
			using (NpgsqlConnection cnx=
				new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {
				cmd.CommandText = "insert into comment (postid,bcontent," +
					"modified,posted,visible,username,applicationname)" +
				    "values (@postid,@bcontent,@modified,@posted," +
				    "@visible,@username,@appname) returning _id";
				cmd.Parameters.AddWithValue ("@postid", postid);
				cmd.Parameters.AddWithValue ("@bcontent", content);
				DateTime now = DateTime.Now;
				cmd.Parameters.AddWithValue ("@modified", now);
				cmd.Parameters.AddWithValue ("@posted", now);
				cmd.Parameters.AddWithValue ("@visible", visible);
				cmd.Parameters.AddWithValue ("@username", from);
				cmd.Parameters.AddWithValue ("@appname", applicationName);
				cnx.Open ();
				return (long) cmd.ExecuteScalar();
			}
		}
		/// <summary>
		/// Validates the comment.
		/// </summary>
		/// <param name="cmtid">Cmtid.</param>
		public override void ValidateComment (long cmtid)
		{
			throw new NotImplementedException ();
		}
		/// <summary>
		/// Updates the comment.
		/// </summary>
		/// <param name="cmtid">Cmtid.</param>
		/// <param name="content">Content.</param>
		/// <param name="visible">If set to <c>true</c> visible.</param>
		public override void UpdateComment 
		(long cmtid, string content, bool visible)
		{
			throw new NotImplementedException ();
		}

		private bool autoValidateComment = true;
		/// <summary>
		/// Gets or sets a value indicating whether this <see cref="Npgsql.Web.Blog.NpgsqlBlogProvider"/> auto validate comment.
		/// </summary>
		/// <value><c>true</c> if auto validate comment; otherwise, <c>false</c>.</value>
		public override bool AutoValidateComment {
			get {
				return autoValidateComment;
			}
			set {
				autoValidateComment=value;
			}
		}

		/// <summary>
		/// Blogs the title.
		/// </summary>
		/// <returns>The title.</returns>
		/// <param name="username">Username.</param>
		public override string BlogTitle
		 (string username)
		{
			throw new NotImplementedException ();
		}

		#endregion
		/// <summary>
		/// Initialize the specified name and config.
		/// </summary>
		/// <param name="name">Name.</param>
		/// <param name="config">Config.</param>
		public override void Initialize 
		(string name, System.Collections.Specialized.NameValueCollection config)
		{
			string cnxName = config ["connectionStringName"];
			connectionString = ConfigurationManager.ConnectionStrings [cnxName].ConnectionString;
			config.Remove ("connectionStringName");
			applicationName = config ["applicationName"];
			config.Remove ("applicationName");
			defaultPageSize = int.Parse ( config ["pageLen"] ?? "10") ;
			base.Initialize (name, config);
		}
		#region implemented abstract members of BlogProvider
		/// <summary>
		/// Gets the post.
		/// </summary>
		/// <returns>The post.</returns>
		/// <param name="postid">Postid.</param>
		public override BlogEntry GetPost (long postid)
		{
			BlogEntry be = null;
			using (NpgsqlConnection cnx=new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {
				cmd.CommandText = "select username, title, bcontent, modified, posted, visible from blog " +
				                  "where applicationname = @appname and _id = @id";
				cmd.Parameters.AddWithValue ("@appname", applicationName);
				cmd.Parameters.AddWithValue ("@id", postid);
				cnx.Open ();
				using (NpgsqlDataReader rdr = cmd.ExecuteReader()) {
					if (rdr.Read ()) {
						be = new BlogEntry ();
						be.Title = rdr.GetString (rdr.GetOrdinal ("title"));
						be.Content = rdr.GetString (rdr.GetOrdinal ("bcontent"));
						be.UserName = rdr.GetString (rdr.GetOrdinal ("username"));
						be.Modified = rdr.GetDateTime (rdr.GetOrdinal ("modified"));
						be.Posted = rdr.GetDateTime (rdr.GetOrdinal ("posted"));
						be.Visible = rdr.GetBoolean (rdr.GetOrdinal ("visible"));
						be.Id = postid;
					}
				}
			}
			return be;
		}
		/// <summary>
		/// Removes the comment.
		/// </summary>
		/// <returns>The comment.</returns>
		/// <param name="cmtid">Cmtid.</param>
		public override long RemoveComment (long cmtid)
		{
			long postid = 0;
			using (NpgsqlConnection cnx = new NpgsqlConnection (connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand ()) {
				cmd.CommandText = "delete from comment where _id = @id returning postid";
				cmd.Parameters.AddWithValue ("id", cmtid);
				cnx.Open ();
				postid = (long) cmd.ExecuteScalar ();
			}
			return postid;
		}
		/// <summary>
		/// Gets the post.
		/// </summary>
		/// <returns>The post.</returns>
		/// <param name="username">Username.</param>
		/// <param name="title">Title.</param>
		public override BlogEntry GetPost (string username, string title)
		{
			BlogEntry be = null;
			using (NpgsqlConnection cnx=new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {
				cmd.CommandText = "select _id,bcontent,modified,posted,visible from blog " +
				                  "where applicationname = @appname and username = @username and title = @title";
				cmd.Parameters.AddWithValue ("@appname", applicationName);
				cmd.Parameters.AddWithValue ("@username", username);
				cmd.Parameters.AddWithValue ("@title", title);
				cnx.Open ();
				using (NpgsqlDataReader rdr = cmd.ExecuteReader()) {
					if (rdr.Read ()) {
						be = new BlogEntry ();
						be.Title = title;
						be.Content = rdr.GetString (rdr.GetOrdinal ("bcontent"));
						be.UserName = username;
						be.Modified = rdr.GetDateTime (rdr.GetOrdinal ("modified"));
						be.Posted = rdr.GetDateTime (rdr.GetOrdinal ("posted"));
						be.Visible = rdr.GetBoolean (rdr.GetOrdinal ("visible"));
						be.Id = rdr.GetInt64 (rdr.GetOrdinal ("_id"));
					}
					rdr.Close ();
				}
				if (be!=null)
				using (NpgsqlCommand cmdtags = cnx.CreateCommand()) {
					List<string> tags = new List<string> ();
					cmd.CommandText = "select tag.name from tag,tagged where tag._id = tagged.tagid and tagged.postid = @pid";
					cmd.Parameters.AddWithValue ("@pid", be.Id);
					using (NpgsqlDataReader rdrt = cmd.ExecuteReader ()) {
						while (rdrt.Read ()) {
							tags.Add (rdrt.GetString (0));
						}
					}
					be.Tags = tags.ToArray ();
				}
			}
			return be;
		}
		/// <summary>
		/// Post the specified username, title, content and visible.
		/// </summary>
		/// <param name="username">Username.</param>
		/// <param name="title">Title.</param>
		/// <param name="content">Content.</param>
		/// <param name="visible">If set to <c>true</c> visible.</param>
		public override long Post (string username, string title, string content, bool visible)
		{
			if (username == null)
				throw new ArgumentNullException("username");
			if (title == null)
				throw new ArgumentNullException("title");
			if (content == null)
				throw new ArgumentNullException("content");
			using (NpgsqlConnection cnx=new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {
				cmd.CommandText = "insert into blog (title,bcontent,modified,posted,visible,username,applicationname)" +
				                  "values (@title,@bcontent,@modified,@posted,@visible,@username,@appname) returning _id";
				cmd.Parameters.AddWithValue ("@title", title);
				cmd.Parameters.AddWithValue ("@bcontent", content);
				DateTime now = DateTime.Now;
				cmd.Parameters.AddWithValue ("@modified", now);
				cmd.Parameters.AddWithValue ("@posted", now);
				cmd.Parameters.AddWithValue ("@visible", visible);
				cmd.Parameters.AddWithValue ("@username", username);
				cmd.Parameters.AddWithValue ("@appname", applicationName);
				cnx.Open ();
				return (long) cmd.ExecuteScalar();
			}
		}
		/// <summary>
		/// Finds the post.
		/// </summary>
		/// <returns>The post.</returns>
		/// <param name="pattern">Pattern.</param>
		/// <param name="searchflags">Searchflags.</param>
		/// <param name="pageIndex">Page index.</param>
		/// <param name="pageSize">Page size.</param>
		/// <param name="totalRecords">Total records.</param>
		public override BlogEntryCollection FindPost (string pattern, FindBlogEntryFlags searchflags, int pageIndex, int pageSize, out int totalRecords)
		{
			BlogEntryCollection c = new BlogEntryCollection ();
			totalRecords = 0;
			using (NpgsqlConnection cnx=new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {
				cmd.CommandText = "select title,bcontent,modified,posted,username,visible from blog " +
					"where applicationname = @appname";
				cmd.Parameters.AddWithValue ("@appname", applicationName);
				if ((searchflags & FindBlogEntryFlags.MatchContent) > 0) {
					cmd.CommandText += " and bcontent like @bcontent";
					cmd.Parameters.AddWithValue ("@bcontent", pattern);
				}
				if ((searchflags & FindBlogEntryFlags.MatchTitle) > 0) {
					cmd.CommandText += " and title like @title";
					cmd.Parameters.AddWithValue ("@title", pattern);
				}
				if ((searchflags & FindBlogEntryFlags.MatchUserName) > 0) {
					cmd.CommandText += " and username like @username";
					cmd.Parameters.AddWithValue ("@username", pattern);
				}
				if ((searchflags & FindBlogEntryFlags.MatchInvisible) == 0) {
					cmd.CommandText += " and visible = true";
				}

				cmd.CommandText += " order by posted desc";
				cnx.Open ();
				using (NpgsqlDataReader rdr = cmd.ExecuteReader()) {
					// pageIndex became one based
					int firstrec = pageIndex * pageSize;
					int lastrec = firstrec + pageSize - 1;
					while (rdr.Read()) {
						if (totalRecords >= firstrec && totalRecords <= lastrec) {
							BlogEntry be = new BlogEntry ();
							be.Title = rdr.GetString (rdr.GetOrdinal ("title"));
							be.Content = rdr.GetString (rdr.GetOrdinal ("bcontent"));
							be.UserName = rdr.GetString (rdr.GetOrdinal ("username"));
							be.Posted = rdr.GetDateTime (rdr.GetOrdinal ("posted"));
							be.Modified = rdr.GetDateTime (rdr.GetOrdinal ("modified"));
							be.Visible =  rdr.GetBoolean (rdr.GetOrdinal ("visible"));
							c.Add (be);
						}
						totalRecords++;
					}
				}
			}
			return c;
		}
		/// <summary>
		/// Removes the post.
		/// </summary>
		/// <param name="username">Username.</param>
		/// <param name="title">Title.</param>
		public override void RemovePost (string username, string title)
		{
			using (NpgsqlConnection cnx=new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {
				cmd.CommandText = "delete from blog where username = @username and applicationname = @appname and title=@title";
				cmd.Parameters.AddWithValue ("@username",username);
				cmd.Parameters.AddWithValue ("@appname", applicationName);
				cmd.Parameters.AddWithValue ("@title",title);
				cnx.Open ();
				cmd.ExecuteNonQuery ();
				cnx.Close();
			}
		}


		int defaultPageSize = 10;
		/// <summary>
		/// Lasts the posts.
		/// </summary>
		/// <returns>The posts.</returns>
		/// <param name="pageIndex">Page index.</param>
		/// <param name="pageSize">Page size.</param>
		/// <param name="totalRecords">Total records.</param>
		public override BlogEntryCollection LastPosts(int pageIndex, int pageSize, out int totalRecords)
		{
			BlogEntryCollection c = new BlogEntryCollection ();
			using (NpgsqlConnection cnx=new NpgsqlConnection(connectionString))
			using (NpgsqlCommand cmd = cnx.CreateCommand()) {

				/*cmd.CommandText = "select blog.* from blog, " +
					"(select max(posted) lpost, username " +
					"from blog where applicationname = @appname " +
					"group by username) as lblog " +
					"where blog.posted = lblog.lpost and blog.username = lblog.username " ;
					*/
				cmd.CommandText = "select * " +
				                  "from blog where applicationname = @appname and visible = true " +
				                  " order by posted desc limit @len" ;

				cmd.Parameters.AddWithValue ("@appname", applicationName);
				cmd.Parameters.AddWithValue ("@len", defaultPageSize*10);
				cnx.Open ();
				using (NpgsqlDataReader rdr = cmd.ExecuteReader()) {
					totalRecords = 0;
					int firstrec = pageIndex * pageSize;
					int lastrec = firstrec + pageSize - 1;
					while (rdr.Read()) {
						if (totalRecords >= firstrec && totalRecords <= lastrec) {
							BlogEntry be = new BlogEntry ();
							be.Title = rdr.GetString (rdr.GetOrdinal ("title"));
							be.Content = rdr.GetString (rdr.GetOrdinal ("bcontent"));
							be.UserName = rdr.GetString (rdr.GetOrdinal ("username"));
							be.Posted = rdr.GetDateTime (rdr.GetOrdinal ("posted"));
							be.Modified = rdr.GetDateTime (rdr.GetOrdinal ("modified"));
							be.Visible = true; // because of sql code used
							c.Add (be);
						}
						totalRecords++;
					}
				}
			}
			return c;
		}
		#endregion
	}
}