/// <summary>Get a string describing a match strength, which handles values in between like "Perfect-2" or "Strong+3".</summary>
/// <param name="value"></param>
/// <returns></returns>
public static string MatchStrengthToString(LoadMatchStrength value)
{
if (value >= LoadMatchStrength.Perfect)
{
return(MatchStrengthToString(LoadMatchStrength.Perfect, value));
}
if (value >= LoadMatchStrength.Comprehensive)
{
return(MatchStrengthToString(LoadMatchStrength.Comprehensive, value));
}
if (value >= LoadMatchStrength.Strong)
{
return(MatchStrengthToString(LoadMatchStrength.Strong, value));
}
if (value >= LoadMatchStrength.Medium)
{
return(MatchStrengthToString(LoadMatchStrength.Medium, value));
}
if (value >= LoadMatchStrength.Weak)
{
return(MatchStrengthToString(LoadMatchStrength.Weak, value));
}
if (value >= LoadMatchStrength.Generic)
{
return(MatchStrengthToString(LoadMatchStrength.Generic, value));
}
if (value > LoadMatchStrength.None)
{
return(MatchStrengthToString(LoadMatchStrength.Fallback, value));
}
return(MatchStrengthToString(LoadMatchStrength.None, value));
}
static InvalidDataException CreateConflictException(AssetLoader loader, LoadMatchStrength matchStrength, IList <AssetFormat> formats)
{
string text = string.Format("{3} {0} loaders matched {1} with strength {2}: {4}",
typeof(AssetFormat).Name,
loader.Name,
MatchStrengthToString(matchStrength),
formats.Count, string.Join(", ", (from i in formats select i.Name)));
return(new InvalidDataException(text));
}
static string MatchStrengthToString(LoadMatchStrength reference, LoadMatchStrength value)
{
if (value < reference)
{
return(reference.ToString() + (int)(value - reference));
}
else
{
return(reference + "+" + (int)(value - reference));
}
}
/// <summary>Find the best <see cref="AssetFormat"/> for loading an <see cref="Asset"/>.</summary>
/// <param name="matchStrength"></param>
/// <param name="loader"></param>
/// <param name="formats"></param>
/// <param name="resolveConflict"></param>
/// <returns></returns>
public static AssetFormat LoadMatchAsset(out LoadMatchStrength matchStrength, AssetLoader loader, IEnumerable <AssetFormat> formats, ResolveLoadConflictCallback resolveConflict = null)
{
if (loader == null)
{
throw new ArgumentNullException("context");
}
if (formats == null)
{
throw new ArgumentNullException("formats");
}
AssetFormat bestFormat = null;
LoadMatchStrength bestMatch = LoadMatchStrength.None;
bool bestConflict = false;
// Attempt to find the one best loader.
foreach (AssetFormat format in formats)
{
if (!format.CanLoad || !format.IsEnabled)
{
continue;
}
LoadMatchStrength match = format.LoadMatch(loader);
loader.Reset();
if (match <= LoadMatchStrength.None || match < bestMatch)
{
continue;
}
if (match == bestMatch)
{
bestConflict = true;
}
else
{
bestFormat = format;
bestMatch = match;
bestConflict = false;
}
}
matchStrength = bestMatch;
// If a single best loader is found, return it.
if (!bestConflict)
{
if (bestFormat == null)
{
throw new InvalidDataException("No loader could be found for " + loader.Name + ".");
}
return(bestFormat);
}
// Otherwise there are multiple formats with equal match strengths; gather those together.
List <AssetFormat> conflicts = new List <AssetFormat>();
foreach (AssetFormat format in formats)
{
if (!format.CanLoad || !format.IsEnabled)
{
continue;
}
loader.Reset();
LoadMatchStrength match = format.LoadMatch(loader);
if (match == bestMatch)
{
conflicts.Add(format);
}
}
// Attempt to resolve the conflict.
bestFormat = null;
if (resolveConflict != null)
{
bestFormat = resolveConflict(loader, conflicts, matchStrength);
}
// If no resolution is found, throw an exception.
if (bestFormat == null)
{
throw CreateConflictException(loader, matchStrength, conflicts);
}
// A resolution was found, so return the best format.
return(bestFormat);
}
static string MatchStrengthToString(LoadMatchStrength reference, LoadMatchStrength value)
{
if (value < reference)
return reference.ToString() + (int)(value - reference);
else
return reference + "+" + (int)(value - reference);
}
static InvalidDataException CreateConflictException(AssetLoader loader, LoadMatchStrength matchStrength, IList<AssetFormat> formats)
{
string text = string.Format("{3} {0} loaders matched {1} with strength {2}: {4}",
typeof(AssetFormat).Name,
loader.Name,
MatchStrengthToString(matchStrength),
formats.Count, string.Join(", ", (from i in formats select i.Name)));
return new InvalidDataException(text);
}
/// <summary>Get a string describing a match strength, which handles values in between like "Perfect-2" or "Strong+3".</summary>
/// <param name="value"></param>
/// <returns></returns>
public static string MatchStrengthToString(LoadMatchStrength value)
{
if (value >= LoadMatchStrength.Perfect)
return MatchStrengthToString(LoadMatchStrength.Perfect, value);
if (value >= LoadMatchStrength.Comprehensive)
return MatchStrengthToString(LoadMatchStrength.Comprehensive, value);
if (value >= LoadMatchStrength.Strong)
return MatchStrengthToString(LoadMatchStrength.Strong, value);
if (value >= LoadMatchStrength.Medium)
return MatchStrengthToString(LoadMatchStrength.Medium, value);
if (value >= LoadMatchStrength.Weak)
return MatchStrengthToString(LoadMatchStrength.Weak, value);
if (value >= LoadMatchStrength.Generic)
return MatchStrengthToString(LoadMatchStrength.Generic, value);
if (value > LoadMatchStrength.None)
return MatchStrengthToString(LoadMatchStrength.Fallback, value);
return MatchStrengthToString(LoadMatchStrength.None, value);
}
/// <summary>Find the best <see cref="AssetFormat"/> for loading an <see cref="Asset"/>.</summary>
/// <param name="matchStrength"></param>
/// <param name="loader"></param>
/// <param name="formats"></param>
/// <param name="resolveConflict"></param>
/// <returns></returns>
public static AssetFormat LoadMatchAsset(out LoadMatchStrength matchStrength, AssetLoader loader, IEnumerable<AssetFormat> formats, ResolveLoadConflictCallback resolveConflict = null)
{
if (loader == null)
throw new ArgumentNullException("context");
if (formats == null)
throw new ArgumentNullException("formats");
AssetFormat bestFormat = null;
LoadMatchStrength bestMatch = LoadMatchStrength.None;
bool bestConflict = false;
// Attempt to find the one best loader.
foreach (AssetFormat format in formats) {
if (!format.CanLoad || !format.IsEnabled)
continue;
LoadMatchStrength match = format.LoadMatch(loader);
loader.Reset();
if (match <= LoadMatchStrength.None || match < bestMatch)
continue;
if (match == bestMatch)
bestConflict = true;
else {
bestFormat = format;
bestMatch = match;
bestConflict = false;
}
}
matchStrength = bestMatch;
// If a single best loader is found, return it.
if (!bestConflict) {
if (bestFormat == null)
throw new InvalidDataException("No loader could be found for " + loader.Name + ".");
return bestFormat;
}
// Otherwise there are multiple formats with equal match strengths; gather those together.
List<AssetFormat> conflicts = new List<AssetFormat>();
foreach (AssetFormat format in formats) {
if (!format.CanLoad || !format.IsEnabled)
continue;
loader.Reset();
LoadMatchStrength match = format.LoadMatch(loader);
if (match == bestMatch)
conflicts.Add(format);
}
// Attempt to resolve the conflict.
bestFormat = null;
if (resolveConflict != null)
bestFormat = resolveConflict(loader, conflicts, matchStrength);
// If no resolution is found, throw an exception.
if (bestFormat == null)
throw CreateConflictException(loader, matchStrength, conflicts);
// A resolution was found, so return the best format.
return bestFormat;
}
