using System;
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Xml;

namespace AIPractice.Shared.Labels
{
    /// <summary>
    /// All labels in this group can be multi-selected.
    /// </summary>
    public class MultiSelectionLabelGroup:LabelGroup
    {
        public MultiSelectionLabelGroup(string id, string title, GroupType type, IEnumerable<ImageLabel> labels) : base(
            id, title, type, labels)
        {

        }

        public static MultiSelectionLabelGroup FromXml(string xmlContent)
        {
            using (var ms = new MemoryStream(Encoding.Unicode.GetBytes(xmlContent)))
            {
                using (var r = XmlReader.Create(ms))
                {
                    r.Read();
                    var id = r.GetAttribute("id");
                    var title = r.GetAttribute("title");
                    var type = (GroupType) int.Parse(r.GetAttribute("type") ?? throw new InvalidOperationException());
                    var labels = new List<ImageLabel>();
                    while (r.NodeType == XmlNodeType.Element &&
                           (r.Name == nameof(DescriptionLabel) ||
                            r.Name == nameof(ConclusionLabel)) || r.Read())
                    {
                        if (r.NodeType == XmlNodeType.EndElement && r.Name == nameof(MultiSelectionLabelGroup))
                        {
                            break;
                        }
                        if (r.Name == nameof(DescriptionLabel))
                        {
                            labels.Add(DescriptionLabel.FromXml(r.ReadOuterXml()));
                        }
                        if (r.Name == nameof(ConclusionLabel))
                        {
                            labels.Add(ConclusionLabel.FromXml(r.ReadOuterXml()));
                        }
                    }
                    return new MultiSelectionLabelGroup(id, title, type, labels);
                }
            }
        }

        public override string ToXml()
        {
            var sb = new StringBuilder();
            sb.Append($"<{nameof(MultiSelectionLabelGroup)} id=\"{Id}\" title=\"{Title}\" type=\"{(int)Type}\">");
            foreach (var label in Labels)
            {
                sb.Append(label.ToXml());
            }
            sb.Append($"</{nameof(MultiSelectionLabelGroup)}>");
            return sb.ToString();
        }
    }
}