// <copyright file="PathsSerializeExtensions.cs" company="MUnique">
// Licensed under the MIT License. See LICENSE file in the project root for full license information.
// </copyright>

namespace MUnique.OpenMU.Pathfinding.PreCalculation;

using System.IO;

/// <summary>
/// Extension methods for paths serialization.
/// </summary>
public static class PathsSerializeExtensions
{
    /// <summary>
    /// The format in which the path infos will be serialized.
    /// </summary>
    public enum PathInfoFormat
    {
        /// <summary>
        /// The compact format.
        /// This format uses just 1 byte for end and 1 byte for next step.
        /// It can only be used for maximumRange lower than 8, because of the space limitation.
        /// </summary>
        Compact,

        /// <summary>
        /// The normal format. Every point uses exactly 2 bytes.
        /// </summary>
        Normal,
    }

    /// <summary>
    /// Serializes the path infos to the target stream.
    /// </summary>
    /// <param name="pathInfos">The path infos.</param>
    /// <param name="target">The target stream.</param>
    /// <param name="format">The format.</param>
    public static void SerializeToStream(this IEnumerable<PathInfo> pathInfos, Stream target, PathInfoFormat format)
    {
        IPathsSerializer serializer = format == PathInfoFormat.Compact ? new CompactPathsSerializer() as IPathsSerializer : new NormalPathsSerializer();
        target.WriteByte((byte)format);
        serializer.Serialize(pathInfos, target);
    }

    /// <summary>
    /// Deserializes the path infos from the source stream.
    /// </summary>
    /// <param name="source">The source stream.</param>
    /// <returns>The path infos.</returns>
    public static IEnumerable<PathInfo> DeserializeFromStream(this Stream source)
    {
        var format = (PathInfoFormat)source.ReadByte();
        IPathsSerializer serializer = format == PathInfoFormat.Compact ? new CompactPathsSerializer() as IPathsSerializer : new NormalPathsSerializer();
        return serializer.Deserialize(source);
    }
}