// (c) Copyright Ascensio System SIA 2010-2022
//
// This program is a free software product.
// You can redistribute it and/or modify it under the terms
// of the GNU Affero General Public License (AGPL) version 3 as published by the Free Software
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// to the effect that Ascensio System SIA expressly excludes the warranty of non-infringement of
// any third-party rights.
//
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// of MERCHANTABILITY or FITNESS FOR A PARTICULAR  PURPOSE. For details, see
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using ASC.Core;

namespace ASC.AuditTrail.Repositories;

[Scope(Additional = typeof(AuditEventsRepositoryExtensions))]
public class AuditEventsRepository
{
    private MessagesContext AuditTrailContext => _lazyAuditTrailContext.Value;

    private readonly Lazy<MessagesContext> _lazyAuditTrailContext;
    private readonly AuditActionMapper _auditActionMapper;
    private readonly TenantManager _tenantManager;
    private readonly IMapper _mapper;

    public AuditEventsRepository(
        AuditActionMapper auditActionMapper,
        TenantManager tenantManager,
        DbContextManager<MessagesContext> dbContextManager,
        IMapper mapper)
    {
        _lazyAuditTrailContext = new Lazy<MessagesContext>(() => dbContextManager.Value);
        _auditActionMapper = auditActionMapper;
        _tenantManager = tenantManager;
        _mapper = mapper;
    }

    private IEnumerable<AuditEventDto> Get(int tenant, DateTime? fromDate, DateTime? to, int? limit)
    {
        var query =
           (from q in AuditTrailContext.AuditEvents
            from p in AuditTrailContext.Users.Where(p => q.UserId == p.Id).DefaultIfEmpty()
            where q.TenantId == tenant
            orderby q.Date descending
            select new AuditEventQuery
            {
                Event = q,
                FirstName = p.FirstName,
                LastName = p.LastName,
                UserName = p.UserName
            });

        if (fromDate.HasValue && to.HasValue)
        {
            query = query.Where(q => q.Event.Date >= fromDate & q.Event.Date <= to);
        }

        if (limit.HasValue)
        {
            query = query.Take((int)limit);
        }

        return _mapper.Map<List<AuditEventQuery>, IEnumerable<AuditEventDto>>(query.ToList());
    }

    public IEnumerable<AuditEventDto> GetByFilter(
        Guid? userId = null,
        ProductType? productType = null,
        ModuleType? moduleType = null,
        ActionType? actionType = null,
        MessageAction? action = null,
        EntryType? entry = null,
        string target = null,
        DateTime? from = null,
        DateTime? to = null,
        int startIndex = 0,
        int limit = 0)
    {
        var tenant = _tenantManager.GetCurrentTenant().Id;

        var query =
          (from q in AuditTrailContext.AuditEvents
           from p in AuditTrailContext.Users.Where(p => q.UserId == p.Id).DefaultIfEmpty()
           where q.TenantId == tenant
           orderby q.Date descending
           select new AuditEventQuery
           {
               Event = q,
               FirstName = p.FirstName,
               LastName = p.LastName,
               UserName = p.UserName
           });

        if (startIndex > 0)
        {
            query = query.Skip(startIndex);
        }
        if (limit > 0)
        {
            query = query.Take(limit);
        }

        if (userId.HasValue && userId.Value != Guid.Empty)
        {
            query = query.Where(r => r.Event.UserId == userId.Value);
        }

        var isNeedFindEntry = entry.HasValue && entry.Value != EntryType.None && target != null;


        if (action.HasValue && action.Value != MessageAction.None)
        {
            query = query.Where(r => r.Event.Action == (int)action);
        }
        else
        {
            IEnumerable<KeyValuePair<MessageAction, MessageMaps>> actions = new List<KeyValuePair<MessageAction, MessageMaps>>();

            var isFindActionType = actionType.HasValue && actionType.Value != ActionType.None;

            if (productType.HasValue && productType.Value != ProductType.None)
            {
                var productMapper = _auditActionMapper.Mappers.FirstOrDefault(m => m.Product == productType.Value);

                if (productMapper != null)
                {
                    if (moduleType.HasValue && moduleType.Value != ModuleType.None)
                    {
                        var moduleMapper = productMapper.Mappers.FirstOrDefault(m => m.Module == moduleType.Value);
                        if (moduleMapper != null)
                        {
                            actions = moduleMapper.Actions;
                        }
                    }
                    else
                    {
                        actions = productMapper.Mappers.SelectMany(r => r.Actions);
                    }
                }
            }
            else
            {
                actions = _auditActionMapper.Mappers
                        .SelectMany(r => r.Mappers)
                        .SelectMany(r => r.Actions);
            }

            if (isFindActionType || isNeedFindEntry)
            {
                actions = actions
                        .Where(a => (!isFindActionType || a.Value.ActionType == actionType.Value) && (!isNeedFindEntry || (entry.Value == a.Value.EntryType1) || entry.Value == a.Value.EntryType2))
                        .ToList();
            }

            if (isNeedFindEntry)
            {
                FindByEntry(q, entry.Value, target, actions);
            }
            else
            {
                var keys = actions.Select(x => (int)x.Key).ToList();
                q.Where(Exp.In("a.action", keys));
            }
        }

        var hasFromFilter = (from.HasValue && from.Value != DateTime.MinValue);
        var hasToFilter = (to.HasValue && to.Value != DateTime.MinValue);

        if (hasFromFilter || hasToFilter)
        {
            if (hasFromFilter)
            {
                if (hasToFilter)
                {
                    query = query.Where(q => q.Event.Date >= from.Value & q.Event.Date <= to.Value);
                }
                else
                {
                    query = query.Where(q => q.Event.Date >= from.Value);
                }
            }
            else if (hasToFilter)
            {
                query = query.Where(q => q.Event.Date <= to.Value);
            }
        }

        return _mapper.Map<List<AuditEventQuery>, IEnumerable<AuditEventDto>>(query.ToList());
    }

    private static void FindByEntry(IQueryable<AuditEventQuery> q, EntryType entry, string target, IEnumerable<KeyValuePair<MessageAction, MessageMaps>> actions)
    {
        var sb = new StringBuilder();

        foreach (var action in actions)
        {
            if (action.Value.EntryType1 == entry)
            {
                sb.Append(string.Format("(a.action = {0} AND SUBSTRING_INDEX(SUBSTRING_INDEX(a.target,',',{1}),',',1) = {2}) OR ", (int)action.Key, -2, target));
            }
            if (action.Value.EntryType2 == entry)
            {
                sb.Append(string.Format("(a.action = {0} AND SUBSTRING_INDEX(SUBSTRING_INDEX(a.target,',',{1}),',',1) = {2}) OR ", (int)action.Key, -1, target));
            }
        }

        sb.Remove(sb.Length - 3, 3);
        q.Where(sb.ToString());
    }

    public int GetCount(int tenant, DateTime? from = null, DateTime? to = null)
    {
        var query = AuditTrailContext.AuditEvents
            .Where(a => a.TenantId == tenant);

        if (from.HasValue && to.HasValue)
        {
            query = query.Where(a => a.Date >= from & a.Date <= to);
        }

        return query.Count();
    }
}

public static class AuditEventsRepositoryExtensions
{
    public static void Register(DIHelper services)
    {
        services.TryAdd<EventTypeConverter>();
    }
}