using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Threading.Tasks;
using System.Web.Mvc;
using MongoDB.Bson;
using MongoDB.Bson.Serialization.Attributes;
using MongoDB.Driver;
using Required = System.ComponentModel.DataAnnotations.RequiredAttribute;

namespace BuildFeed.Model
{
    [DataObject]
    public class MetaItemModel
    {
        [Key]
        [BsonId]
        [@Required]
        public MetaItemKey Id { get; set; }

        [DisplayName("Meta Description")]
        public string MetaDescription { get; set; }

        [DisplayName("Page Content")]
        [AllowHtml]
        public string PageContent { get; set; }
    }

    public class MetaItem
    {
        private const string META_COLLECTION_NAME = "metaitem";
        private readonly BuildRepository _bModel;

        private readonly IMongoCollection<MetaItemModel> _metaCollection;

        public MetaItem()
        {
            MongoClientSettings settings = new MongoClientSettings
            {
                Server = new MongoServerAddress(MongoConfig.Host, MongoConfig.Port)
            };

            if (!string.IsNullOrEmpty(MongoConfig.Username) && !string.IsNullOrEmpty(MongoConfig.Password))
            {
                settings.Credentials = new List<MongoCredential>
                {
                    MongoCredential.CreateCredential(MongoConfig.Database, MongoConfig.Username, MongoConfig.Password)
                };
            }

            MongoClient dbClient = new MongoClient(settings);

            _metaCollection = dbClient.GetDatabase(MongoConfig.Database).GetCollection<MetaItemModel>(META_COLLECTION_NAME);
            _bModel = new BuildRepository();
        }

        [DataObjectMethod(DataObjectMethodType.Select, false)]
        public async Task<IEnumerable<MetaItemModel>> Select()
        {
            return await _metaCollection.Find(new BsonDocument()).ToListAsync();
        }

        [DataObjectMethod(DataObjectMethodType.Select, true)]
        public async Task<IEnumerable<MetaItemModel>> SelectByType(MetaType type)
        {
            return await _metaCollection.Find(f => f.Id.Type == type).ToListAsync();
        }

        [DataObjectMethod(DataObjectMethodType.Select, false)]
        public async Task<MetaItemModel> SelectById(MetaItemKey id)
        {
            return await _metaCollection.Find(f => f.Id.Type == id.Type && f.Id.Value == id.Value).SingleOrDefaultAsync();
        }

        [DataObjectMethod(DataObjectMethodType.Select, false)]
        public async Task<IEnumerable<string>> SelectUnusedLabs()
        {
            string[] labs = await _bModel.SelectAllLabs();

            List<MetaItemModel> usedLabs = await _metaCollection.Find(f => f.Id.Type == MetaType.Lab).ToListAsync();

            return from l in labs
                   where usedLabs.All(ul => ul.Id.Value != l)
                   select l;
        }

        [DataObjectMethod(DataObjectMethodType.Select, false)]
        public async Task<IEnumerable<string>> SelectUnusedVersions()
        {
            BuildVersion[] versions = await _bModel.SelectAllVersions();

            List<MetaItemModel> usedVersions = await _metaCollection.Find(f => f.Id.Type == MetaType.Version).ToListAsync();

            return from v in versions
                   where usedVersions.All(ul => ul.Id.Value != v.ToString())
                   select v.ToString();
        }

        [DataObjectMethod(DataObjectMethodType.Select, false)]
        public async Task<IEnumerable<string>> SelectUnusedYears()
        {
            int[] years = await _bModel.SelectAllYears();

            List<MetaItemModel> usedYears = await _metaCollection.Find(f => f.Id.Type == MetaType.Year).ToListAsync();

            return from y in years
                   where usedYears.All(ul => ul.Id.Value != y.ToString())
                   select y.ToString();
        }

        [DataObjectMethod(DataObjectMethodType.Insert, true)]
        public async Task Insert(MetaItemModel item)
        {
            await _metaCollection.InsertOneAsync(item);
        }

        [DataObjectMethod(DataObjectMethodType.Update, true)]
        public async Task Update(MetaItemModel item)
        {
            await _metaCollection.ReplaceOneAsync(f => f.Id.Type == item.Id.Type && f.Id.Value == item.Id.Value, item);
        }

        [DataObjectMethod(DataObjectMethodType.Insert, false)]
        public async Task InsertAll(IEnumerable<MetaItemModel> items)
        {
            await _metaCollection.InsertManyAsync(items);
        }

        [DataObjectMethod(DataObjectMethodType.Delete, true)]
        public async Task DeleteById(MetaItemKey id)
        {
            await _metaCollection.DeleteOneAsync(f => f.Id.Type == id.Type && f.Id.Value == id.Value);
        }
    }

    public class MetaItemKey
    {
        public MetaType Type { get; set; }
        public string Value { get; set; }

        public MetaItemKey()
        {
        }

        public MetaItemKey(string id)
        {
            string[] items = id.Split(':');
            Type = (MetaType)Enum.Parse(typeof(MetaType), items[0]);
            Value = items[1];
        }

        public override string ToString()
        {
            return $"{Type}:{Value}";
        }
    }

    public enum MetaType
    {
        Lab,
        Version,
        Source,
        Year
    }
}