using System.Collections.Generic;
using System.Linq;
using UIWidgetsSample;

namespace ChatComponents
{
    public enum RoomType
    {
        channel,
        direct,
        group,
        unsupported
    }


    /// A class that represents a room where 2 or more participants can chat
    public class Room : Equatable
    {
        /// Created room timestamp, in ms
        public readonly int? createdAt;

        /// Room"s unique ID
        public readonly string id;

        /// Room"s image. In case of the [RoomType.direct] - avatar of the second person,
        /// otherwise a custom image [RoomType.group].
        public readonly string imageUrl;

        /// Additional custom metadata or attributes related to the room
        public readonly Dictionary<string, object> metadata;

        /// Room"s name. In case of the [RoomType.direct] - name of the second person,
        /// otherwise a custom name [RoomType.group].
        public readonly string name;

        /// [RoomType]
        public readonly RoomType type;

        /// List of users which are in the room
        public readonly List<User> users;

        /// Creates a [Room]
        public Room(
            RoomType type,
            List<User> users,
            string id,
            int? createdAt = null,
            string imageUrl = null,
            Dictionary<string, object> metadata = null,
            string name = null
        )
        {
            this.type = type;
            this.users = users;
            this.id = id;
            this.createdAt = createdAt;
            this.imageUrl = imageUrl;
            this.metadata = metadata;
            this.name = name;
        }

        /// Equatable props
        public override List<object> props => new List<object>
            {createdAt, id, imageUrl, metadata, name, type, users};

        /// Creates room from a map (decoded JSON).
        public Room fromJson(Dictionary<string, object> json)
        {
            var users = (json["users"] as List<Dictionary<string, object>>);
            var usersList = new List<User>();
            foreach (var user in users){
                if (User.fromJson(user) != null)
                {
                    usersList.Add(User.fromJson(user));
                }
            
            }

            return new Room(
                createdAt: json["createdAt"] as int?,
                id: json["id"] as string,
                imageUrl: json["imageUrl"] as string,
                metadata: json["metadata"] as Dictionary<string, object>,
                name: json["name"] as string,
                type: ChatRoomUtils.getRoomTypeFromString(json["type"] as string),
                users: usersList);
        }

        /// Converts room to the map representation, encodable to JSON.
        public Dictionary<string, object> toJson()
        {
            var users = new List<User>();
            return new Dictionary<string, object>
            {
                {"createdAt", createdAt},
                {"id", id},
                {"imageUrl", imageUrl},
                {"metadata", metadata},
                {"name", name},
                {"type", ChatRoomUtils.toShortString(type)},
                {"users", users.Where(e => e.toJson() != null).ToList()}
            };
        }

        /// Creates a copy of the room with an updated data.
        /// [imageUrl] and [name] with null values will nullify existing values
        /// [metadata] with null value will nullify existing metadata, otherwise
        /// both metadatas will be merged into one Map, where keys from a passed
        /// metadata will overwite keys from the previous one.
        /// [type] and [users] with null values will be overwritten by previous values.
        private Room copyWith(
            string imageUrl = null,
            Dictionary<string, object> metadata = null,
            string name = null,
            RoomType? type = null,
            List<User> users = null
        )
        {
            var result = new Dictionary<string, object>();
            if (this.metadata != null)
                foreach (var metaItem in this.metadata)
                    result.Add(metaItem.Key, metaItem.Value);
            foreach (var metaItem in metadata) result.Add(metaItem.Key, metaItem.Value);


            return new Room(
                id: id,
                imageUrl: imageUrl,
                metadata: metadata == null
                    ? null
                    : result,
                name: name,
                type: type ?? this.type,
                users: users ?? this.users
            );
        }
    }
}