using SharpChat.ClientCommands;
using System.Globalization;
using System.Text;

namespace SharpChat {
    public class User(
        string userId,
        string userName,
        ColourInheritable colour,
        int rank,
        UserPermissions perms,
        string nickName = "",
        UserStatus status = UserStatus.Online,
        string statusText = ""
    ) {
        public const int DEFAULT_SIZE = 30;
        public const int DEFAULT_MINIMUM_DELAY = 10000;
        public const int DEFAULT_RISKY_OFFSET = 5;

        public string UserId { get; } = userId;
        public string UserName { get; set; } = userName ?? throw new ArgumentNullException(nameof(userName));
        public ColourInheritable Colour { get; set; } = colour;
        public int Rank { get; set; } = rank;
        public UserPermissions Permissions { get; set; } = perms;
        public string NickName { get; set; } = nickName;
        public UserStatus Status { get; set; } = status;
        public string StatusText { get; set; } = statusText;

        public string LegacyName => string.IsNullOrWhiteSpace(NickName) ? UserName : $"~{NickName}";

        public string LegacyNameWithStatus {
            get {
                StringBuilder sb = new();

                if(Status == UserStatus.Away) {
                    string statusText = StatusText.Trim();
                    StringInfo sti = new(statusText);
                    if(Encoding.UTF8.GetByteCount(statusText) > AFKClientCommand.MAX_BYTES
                        || sti.LengthInTextElements > AFKClientCommand.MAX_GRAPHEMES)
                        statusText = sti.SubstringByTextElements(0, Math.Min(sti.LengthInTextElements, AFKClientCommand.MAX_GRAPHEMES)).Trim();

                    sb.AppendFormat("<{0}>_", statusText.ToUpperInvariant());
                }

                sb.Append(LegacyName);

                return sb.ToString();
            }
        }

        public bool Can(UserPermissions perm, bool strict = false) {
            UserPermissions perms = Permissions & perm;
            return strict ? perms == perm : perms > 0;
        }

        public bool NameEquals(string name) {
            return string.Equals(name, UserName, StringComparison.InvariantCultureIgnoreCase)
                || string.Equals(name, NickName, StringComparison.InvariantCultureIgnoreCase)
                || string.Equals(name, LegacyName, StringComparison.InvariantCultureIgnoreCase)
                || string.Equals(name, LegacyNameWithStatus, StringComparison.InvariantCultureIgnoreCase);
        }

        public override int GetHashCode() {
            return UserId.GetHashCode();
        }

        public static string GetDMChannelName(User user1, User user2) {
            return string.Compare(user1.UserId, user2.UserId, StringComparison.InvariantCultureIgnoreCase) > 0
                ? $"@{user2.UserId}-{user1.UserId}"
                : $"@{user1.UserId}-{user2.UserId}";
        }
    }
}