using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using MongoDB.Bson;
using MongoDB.Driver;

namespace BuildFeed.Model
{
    public partial class BuildRepository
    {
        public async Task<int[]> SelectAllYears(int limit = -1, int skip = 0)
        {
            var query =
                _buildCollection.Aggregate()
                    .Match(Builders<Build>.Filter.Ne(b => b.BuildTime, null))
                    .Group(new BsonDocument("_id", new BsonDocument("$year", $"${nameof(Build.BuildTime)}")))
                    .Sort(new BsonDocument("_id", -1))
                    .Skip(skip);

            if (limit > 0)
            {
                query = query.Limit(limit);
            }

            var grouping = await query.ToListAsync();

            return (from g in grouping
                where !g["_id"].IsBsonNull
                select g["_id"].AsInt32).ToArray();
        }

        public async Task<long> SelectAllYearsCount()
        {
            var query = await _buildCollection.Aggregate()
                .Match(Builders<Build>.Filter.Ne(b => b.BuildTime, null))
                .Group(new BsonDocument("_id", new BsonDocument("$year", $"${nameof(Build.BuildTime)}")))
                .ToListAsync();

            return query.Count;
        }

        public async Task<List<Build>> SelectYear(int year, int limit = -1, int skip = 0)
        {
            var query =
                _buildCollection.Find(Builders<Build>.Filter.And(
                        Builders<Build>.Filter.Gte(b => b.BuildTime,
                            new DateTime(year, 1, 1, 0, 0, 0, DateTimeKind.Utc)),
                        Builders<Build>.Filter.Lte(b => b.BuildTime,
                            new DateTime(year, 12, 31, 23, 59, 59, DateTimeKind.Utc))))
                    .Sort(sortByCompileDate)
                    .Skip(skip);

            if (limit > 0)
            {
                query = query.Limit(limit);
            }

            return await query.ToListAsync();
        }

        public async Task<long> SelectYearCount(int year) => await
            _buildCollection.CountAsync(Builders<Build>.Filter.And(
                Builders<Build>.Filter.Gte(b => b.BuildTime, new DateTime(year, 1, 1, 0, 0, 0, DateTimeKind.Utc)),
                Builders<Build>.Filter.Lte(b => b.BuildTime,
                    new DateTime(year, 12, 31, 23, 59, 59, DateTimeKind.Utc))));
    }
}