using System.Collections.Generic;
using Vellum;

namespace Clave.Vellum
{
    /// <summary>
    /// Saves a ChordSet as a list of its chords, each with its priority and whether it is enabled.
    /// </summary>
    /// <remarks>
    /// Loading adds the chords again, which ranks them against each other as if they had been added in code.
    /// </remarks>
    public sealed class ChordSetConverter : SaveConverter<ChordSet>
    {
        public const string ChordsKey = "chords";
        public const string ChordKey = "chord";
        public const string PriorityKey = "priority";
        public const string EnabledKey = "enabled";

        public override SaveNode Write(ChordSet value, SaveSession session)
        {
            var chords = new List<SavedChord>();
            foreach (Chord chord in value)
            {
                chords.Add(new SavedChord(chord, value.PriorityOf(chord), value.IsEnabled(chord)));
            }

            return SavedChords.Write(chords, session);
        }

        public override ChordSet Read(SaveNode node, SaveSession session)
        {
            var builder = new ChordSetBuilder();
            foreach (SavedChord saved in SavedChords.Read(node, session))
            {
                builder.Add(saved.Chord, saved.Priority);
                if (!saved.Enabled)
                {
                    builder.SetEnabled(saved.Chord, false);
                }
            }

            return builder.Build();
        }

        public override bool TryListChildren(SaveNode node, ChildList children)
        {
            return SavedChords.TryListChildren(node, children);
        }
    }
}