source: trunk/sources/HeuristicLab.Persistence/3.3/Interfaces/ICompositeSerializer.cs @ 3155

using System;
using System.Collections.Generic;
using HeuristicLab.Persistence.Core;

namespace HeuristicLab.Persistence.Interfaces {

  /// <summary>
  /// A composite serializer does not directly transform an object into its
  /// serialized form. It merely decomposes into other objects, that can
  /// later be used to recompose the same object.
  /// </summary>
  public interface ICompositeSerializer {

    /// <summary>
    /// Defines the Priorty of this composite serializer. Higher number means
    /// higher prioriy. Negative numbers are fallback serializers that are
    /// disabled by default.
    /// 
    /// All default generic composite serializers have priority 100. Specializations
    /// have priority 200 so they will  be tried first. Priorities are
    /// only considered for default configurations.
    /// </summary>
    int Priority { get; }

    /// <summary>
    /// Determines for every type whether the composite serializer is applicable.
    /// </summary>
    /// <param name="type">The type.</param>
    /// <returns>
    /// <c>true</c> if this instance can serialize the specified type; otherwise, <c>false</c>.
    /// </returns>
    bool CanSerialize(Type type);

    /// <summary>
    /// Give a reason if possibly why the given type cannot be serialized by this
    /// ICompositeSerializer.
    /// </summary>
    /// <param name="type">The type.</param>
    /// <returns>A string justifying why type cannot be serialized.</returns>
    string JustifyRejection(Type type);

    /// <summary>
    /// Generate MetaInfo necessary for instance creation. (e.g. dimensions
    /// necessary for array creation.
    /// </summary>
    /// <param name="obj">An object.</param>
    /// <returns>An enumerable of <see cref="Tag"/>s.</returns>
    IEnumerable<Tag> CreateMetaInfo(object obj);

    /// <summary>
    /// Decompose an object into <see cref="Tag"/>s, the tag name can be null,
    /// the order in which elements are generated is guaranteed to be
    /// the same as they will be supplied to the Populate method.
    /// </summary>
    /// <param name="obj">An object.</param>
    /// <returns>An enumerable of <see cref="Tag"/>s.</returns>
    IEnumerable<Tag> Decompose(object obj);

    /// <summary>
    /// Create an instance of the object using the provided meta information.
    /// </summary>
    /// <param name="type">A type.</param>
    /// <param name="metaInfo">The meta information.</param>
    /// <returns>A fresh instance of the provided type.</returns>
    object CreateInstance(Type type, IEnumerable<Tag> metaInfo);

    /// <summary>
    /// Fills an object with values from the previously generated <see cref="Tag"/>s
    /// in Decompose. The order in which the values are supplied is
    /// the same as they where generated. <see cref="Tag"/> names might be null.
    /// </summary>
    /// <param name="instance">An empty object instance.</param>
    /// <param name="tags">The tags.</param>
    /// <param name="type">The type.</param>
    void Populate(object instance, IEnumerable<Tag> tags, Type type);
  }

}