using System;
using System.Collections.Generic;
using System.Linq;
using Interfaces;
using SQLite.Net;
using SQLite.Net.Platform.Win32;

namespace SQLiteRepository
{
    public class SQLiteRepository : IRepository
    {
        private readonly SQLiteConnection _connection;
        private string _path = "flexitimedb.db";

        public SQLiteRepository()
        {
            _connection = new SQLiteConnection(new SQLitePlatformWin32(), _path);

            _connection.CreateTable<CardUniqueId>();
            _connection.CreateTable<UserIdentity>();
            _connection.CreateTable<TimeLog>();
        }

        public UserList GetUsers()
        {
            var ret = new UserList();

            var users = _connection.Query<UserIdentity>(SQLiteProcedures.GET_ALL_USERS);

            if (!users.Any())
            {
                ret.PageNumber = 1;
                ret.PageSize = 20;
                return ret;
            }

            foreach (var user in users)
            {
                var userObj = ChangeToUserObject(user);
                var cards = _connection.Query<CardUniqueId>(
                    SQLiteProcedures.GET_CARDS_BY_USER_ID,
                    user.Id);

                foreach (var card in cards)
                {
                    userObj.AssociatedIdentifiers.Add(new Identifier()
                    {
                        UniqueId = card.CardUId,
                        IsAssociatedToUser = true,
                        Id = card.Id
                    });
                }
                ret.Users.Add(userObj);
            }
            ret.PageSize = 20;
            ret.PageNumber = 1;

            return ret;
        }

        public UserList Search(string searchParam)
        {
            var ret = new UserList();
            searchParam = string.Format("%{0}%", searchParam);
            var users = _connection.Query<UserIdentity>(
                SQLiteProcedures.SEARCH_USER_LIST,
                searchParam, searchParam);

            if (!users.Any())
            {
                ret.PageNumber = 1;
                ret.PageSize = 20;
                return ret;
            }

            foreach (var user in users)
            {
                var userObj = ChangeToUserObject(user);
                var cards = _connection.Query<CardUniqueId>(
                    SQLiteProcedures.GET_CARDS_BY_USER_ID,
                    user.Id);

                foreach (var card in cards)
                {
                    userObj.AssociatedIdentifiers.Add(new Identifier()
                    {
                        UniqueId = card.CardUId,
                        IsAssociatedToUser = true,
                        Id = card.Id
                    });
                }
                ret.Users.Add(userObj);
            }
            ret.PageSize = 20;
            ret.PageNumber = 1;

            return ret;
        }

        public User GetUser(int id)
        {
            var ret = new User();

            var users = _connection.Query<UserIdentity>(
                SQLiteProcedures.GET_USER_BY_ID,
                id);

            if (!users.Any()) return ret;

            var user = users.First();
            ret = ChangeToUserObject(user);
            var cards = _connection.Query<CardUniqueId>(
                SQLiteProcedures.GET_CARDS_BY_USER_ID,
                user.Id);

            foreach (var card in cards)
            {
                ret.AssociatedIdentifiers.Add(new Identifier { UniqueId = card.CardUId, IsAssociatedToUser = true, Id = card.Id});
            }

            return ret;
        }

        public TimeLogList GetTimeLogs(int userId)
        {
            throw new NotImplementedException();
        }

        public TimeLogList GetTimeLogs(int userId, int calendarWeek)
        {
            throw new NotImplementedException();
        }

        public IdentifierList GetUnassignedIdentifierList()
        {
            var ret = new IdentifierList();
            var cardQuery = _connection.Query<CardUniqueId>(
                SQLiteProcedures.GET_UNASSIGNED_CARD_LIST,
                Constants.UNASSIGNED_CARD_USER_ID);

            foreach (var card in cardQuery)
            {
                ret.data.Add(new Identifier
                {
                    Id = card.Id,
                    IsAssociatedToUser = card.UserId_FK != Constants.UNASSIGNED_CARD_USER_ID,
                    UniqueId = card.CardUId
                });
            }
            return ret;
        }

        //TODO: add method which returns userId? maybe as ref?
        public OperationResponse UpdateUser(User user)
        {
            //if(user.UserId <=0) return OperationResponse.FAILED;

            var ret = OperationResponse.NONE;
            var cardIds = new List<int>();

            //Get a list of current cards, convert into a list of Identifier Objects..
            var currentCards =
                _connection.Query<CardUniqueId>(SQLiteProcedures.GET_CARDS_BY_USER_ID, user.UserId)
                    .Select(x => new Identifier {Id = x.Id, IsAssociatedToUser = true, UniqueId = x.CardUId});
            var cardsToRemove = currentCards.Except(user.AssociatedIdentifiers).Select(x=>x.Id).ToList();

            #region GetUnique Identifiers (what am i doing here?)
            foreach (var card in user.AssociatedIdentifiers)
            {
                var existingCard = _connection.Query<CardUniqueId>(
                    SQLiteProcedures.GET_CARDS_BY_UNIQUE_ID, card.UniqueId);

                if (!existingCard.Any())
                {
                    var cardInsert = new CardUniqueId { CardUId = card.UniqueId, UserId_FK = -1 };
                    _connection.Insert(cardInsert);
                    cardIds.Add(cardInsert.Id);
                    if (ret < OperationResponse.CREATED)
                        ret = OperationResponse.CREATED;    //only change it if my status supercedes.
                }
                else
                {
                    cardIds.Add(existingCard.First().Id);
                    if (ret < OperationResponse.UPDATED)
                        ret = OperationResponse.UPDATED;
                }
            } 
            #endregion

            #region Update/Create User
            int userId;
            var userQuery = _connection.Query<UserIdentity>(
                SQLiteProcedures.GET_USER_BY_FIRST_AND_LAST,
                user.FirstName, user.LastName);

            if (userQuery.Any())
            {
                userId = userQuery.First().Id;
                if (ret < OperationResponse.UPDATED)
                    ret = OperationResponse.UPDATED;
            }
            else
            {
                var userInsert = new UserIdentity
                {
                    FirstName = user.FirstName,
                    LastName = user.LastName,
                    HoursPerWeek = user.HoursPerWeek
                };
                _connection.Insert(userInsert);
                userId = userInsert.Id;
                if (ret < OperationResponse.CREATED)
                    ret = OperationResponse.CREATED;
            } 
            #endregion

            #region Update Card/Unique Id entries.
            foreach (var cardId in cardIds)
            {
                _connection.Query<CardUniqueId>(
                    SQLiteProcedures.UPDATE_CARD_USER_ID,
                    userId, cardId);
            }
            foreach (var card in cardsToRemove)
            {
                _connection.Query<CardUniqueId>(
                    SQLiteProcedures.UPDATE_CARD_USER_ID,
                    -1, card);
            } 
            #endregion

            return ret;
        }

        public OperationResponse LogEventTime(Identifier identifier)
        {
            var cardIdQuery = _connection.Query<CardUniqueId>(
                   SQLiteProcedures.GET_CARDS_BY_UNIQUE_ID,
                   identifier.UniqueId);
            
            var ident = new CardUniqueId();
            if (!cardIdQuery.Any())
            {
                //new card, create it!
                ident.UserId_FK = -1;
                ident.CardUId = identifier.UniqueId;
                _connection.Insert(ident);
            }
            else
            {
                //TODO: handle when more than one comes back. should NEVER happen but....
                ident = cardIdQuery.First();
            }

            var userId = ident.UserId_FK;

            //TODO: Handle In/Out Flag..
            //TODO: Handle When the identifier is assigned to a user (identifier has -1)
            var timeLog = new TimeLog
            {
                SwipeEventDateTime = DateTime.UtcNow,
                UserId_FK = userId,
                IdentifierId = ident.Id
            };
            
            _connection.Insert(timeLog);

            return OperationResponse.SUCCESS;
        }

        private User ChangeToUserObject(UserIdentity user)
        {
            return new User
            {
                UserId = user.Id,
                FirstName = user.FirstName,
                LastName = user.LastName,
                HoursPerWeek = user.HoursPerWeek,
                IsContractor = user.IsContractor
            };
        }
    }
}