// API.cs
// 
// Copyright (C) 2009 Bartek Jasicki
//
// This file is part of Grubng.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.
//

/**@file Database.cs
 * Provide function for server API.*/

using System;

namespace grubupload
{
	
	/**Provide function for server API.*/
	internal static class API
	{
		/// <summary>
		/// Function return status of server
		/// </summary>
		/// <param name="freespace">
		/// A <see cref="System.Boolean"/> True is is enough free disk space on server, otherwise false
		/// </param>
		/// <param name="uploading">
		/// A <see cref="System.Boolean"/> True if server uploading .arc files to database.
		/// </param>
		/// <param name="connected">
		/// A <see cref="System.Int16"/> Amount of connected clients to server.
		/// </param>
		/// <param name="version">
		/// A <see cref="System.String"/> Version of server
		/// </param>
		/// <param name="workpath">
		/// A <see cref="System.String"/> Full path to working directory
		/// </param>
		/// <returns>
		/// A <see cref="System.String"/> Status of server
		/// </returns>
		public static string Status(bool freespace, bool uploading, short connected, ref string version, ref string workpath)
		{
			System.Text.StringBuilder returnvalue = new System.Text.StringBuilder();
			if (freespace && !uploading)
			{
				returnvalue.Append("OK;");
			}
			if (freespace && uploading)
			{
				returnvalue.Append("Warning;");
			}
			if (!freespace)
			{
				returnvalue.Append("Error;");
			}
			returnvalue.Append(connected);
			returnvalue.Append(";");
			returnvalue.Append(version);
			returnvalue.Append(";");
			Mono.Unix.UnixDriveInfo drive = new Mono.Unix.UnixDriveInfo(workpath);
			returnvalue.Append(Math.Round((Convert.ToDouble(drive.AvailableFreeSpace) / Convert.ToDouble(drive.TotalSize)) * 100, 1));
			drive = null;
			return returnvalue.ToString();
		}
		
		/**Function read from database weekly stats for user.
		 * @param username Username in database.
		 * @param db Object to Database class.
		 * @return string with weekly selected user stats.*/
		public static string UserWeekly(string username, ref Database db)
		{
			string result = db.ReadDB("SELECT urls FROM weekly WHERE user='" + username + "'", 1);
			string[] urls = result.Split('\n');
			int urlsum = 0;
			int arcs = 0;
			foreach (string url in urls)
			{
				if (String.IsNullOrEmpty(url.Trim()))
				{
					break;
				}
				urlsum += Convert.ToInt32(url.Trim());
				arcs ++;
			}
			string startdate = String.Empty;
			string enddate = String.Empty;
			if (urlsum > 0)
			{
				startdate = db.ReadDB("SELECT MIN(senddate) FROM weekly WHERE user='" + username + "'", 
				                      1);
				startdate = DateTime.FromFileTime(Convert.ToInt64(startdate.Trim())).ToShortDateString();
				enddate = db.ReadDB("SELECT MAX(senddate) FROM weekly WHERE user='" + username + "'", 1);
				enddate = DateTime.FromFileTime(Convert.ToInt64(enddate.Trim())).ToShortDateString();
				return arcs.ToString() + "," + urlsum + "," + startdate + "," + enddate;
			}
			else
			{
				return "No user in database";
			}
		}
		
		/**Function read from database stats for user.
		 * @param username Username in database.
		 * @param table Name of table with stats.
		 * @param db Object to Database class.
		 * @return string with selected user stats.*/
		public static string UserStats(string username, string year, string month, string table, ref Database db)
		{
			string result;
			if (table == "monthly")
			{
				if ((String.IsNullOrEmpty(year)) && (String.IsNullOrEmpty(month)))
				{
					result = db.ReadDB("SELECT user, year, month, arcs, urls FROM monthly WHERE user='" + 
					                   username + "'", 5);
				}
				else
				{
					result = db.ReadDB("SELECT user, arcs, urls FROM monthly WHERE user='" + username + 
					                   "'" + " AND year=" + year + " AND month=" + month, 3);
				}
			}
			else
			{
				if (String.IsNullOrEmpty(year))
				{
					result = db.ReadDB("SELECT user, year, arcs, urls FROM yearly WHERE user='" + 
					                   username + "'", 4);
				}
				else
				{
					result = db.ReadDB("SELECT user, arcs, urls FROM yearly WHERE user='" + 
					                   username + "'" + " AND year=" + year, 3);
				}
			}
			char[] parameters = new char[2] {'\n', ','};
			result = result.TrimEnd(parameters);
			if (String.IsNullOrEmpty(result))
			{
				result = "No user in database";
			}
			return result;
		}
		
		/**Function read from database stats for users.
		 * @param offset Number of user from which start count stats.
		 * @param year Year from which start count stats.
		 * @param month Month from which start count stats.
		 * @param table Name of table with stats.
		 * @param db Object to Database class.
		 * @return string with users stats.*/
		public static string ListUsers(string offset, string year, string month, string table, ref Database db)
		{
			System.Text.StringBuilder result = new System.Text.StringBuilder();
			string date = String.Empty;
			switch (table)
			{
			case "weekly":
				string startdate = DateTime.UtcNow.AddDays(-7).ToFileTime().ToString();
				result = result.Append(db.ReadDB("SELECT user FROM weekly" + " WHERE senddate > " + 
				                                 startdate + " GROUP BY user LIMIT 20 OFFSET " + offset, 
				                                 1));
				break;
			case "monthly":
				date = db.ReadDB("SELECT year, month FROM monthly GROUP BY year, month", 2);
				date = date.Replace(',', '/');
				date = date.TrimEnd('\n');
				date = date.Replace('\n', ',');
				date = date + '\n';
				result = result.Append(db.ReadDB("SELECT user FROM monthly WHERE year=" + 
				                                 year + " AND month=" + month + 
				                                 " GROUP BY user LIMIT 20 OFFSET " + offset, 1));
				break;
			case "yearly":
				date = db.ReadDB("SELECT year FROM yearly GROUP BY year", 1);
				result = result.Append(db.ReadDB("SELECT user FROM yearly WHERE year=" + 
				                                 year + " GROUP BY user LIMIT 20 OFFSET " + offset, 1));
				break;
			default:
				break;
			}
			if (result.Length == 0)
			{
				result = new System.Text.StringBuilder("No users");
			}
			else
			{
				string[] users = result.ToString().Split('\n');
				result = new System.Text.StringBuilder();
				foreach (string user in users)
				{
					if (String.IsNullOrEmpty(user.Trim()))
					{
						break;
					}
					if (table == "weekly")
					{
						result.Append(user.Trim());
						result.Append(",");
						result.Append(API.UserWeekly(user.Trim(), ref db));
						result.Append("\n");
					}
					else
					{
						result.Append(API.UserStats(user.Trim(), year, month, table, ref db));
						result.Append("\n");
					}
				}
				result = new System.Text.StringBuilder(result.ToString().TrimEnd('\n'));
			}
			return date + result.ToString();
		}
		
		/**Function read overall of send arc files and urls to server.
		 * @param username Username in database.
		 * @param db Object to Database class.
		 * @return string with overall stats.*/
		public static string OverallStats(string username, ref Database db)
		{
			string result;
			if (String.IsNullOrEmpty(username))
			{
				result = db.ReadDB("SELECT SUM(arcs), SUM(urls), COUNT(user) FROM yearly", 3);
			}
			else
			{
				result = db.ReadDB("SELECT SUM(arcs), SUM(urls) FROM yearly WHERE user='" + 
				                   username + "'", 2);
				result = username + "," + result;
			}
			return result;
		}
	}
}