/// <summary>Try to apply a text operation.</summary>
/// <param name="target">The target map to change.</param>
/// <param name="operation">The text operation to apply.</param>
/// <param name="error">An error indicating why applying the operation failed, if applicable.</param>
/// <returns>Returns whether applying the operation succeeded.</returns>
private bool TryApplyTextOperation(Map target, TextOperation operation, out string error)
{
var targetRoot = operation.GetTargetRoot();
switch (targetRoot)
{
case TextOperationTargetRoot.MapProperties:
{
// validate
if (operation.Target.Length > 2)
return this.Fail($"a '{TextOperationTargetRoot.MapProperties}' path must only have one other segment for the property name.", out error);
// get key/value
string key = operation.Target[1].Value;
string value = target.Properties.TryGetValue(key, out PropertyValue property)
? property.ToString()
: null;
// apply
target.Properties[key] = operation.Apply(value);
}
break;
default:
return this.Fail(
targetRoot == null
? $"unknown path root '{operation.Target[0]}'."
: $"path root '{targetRoot}' isn't valid for an {nameof(PatchType.EditMap)} patch",
out error
);
}
error = null;
return true;
}
/// <summary>Try to apply a text operation.</summary>
/// <param name="operation">The text operation to apply.</param>
/// <param name="hasEntry">Get whether the collection has the given entry.</param>
/// <param name="getEntry">Get an entry from the collection.</param>
/// <param name="removeEntry">Remove an entry from the collection.</param>
/// <param name="setEntry">Add or replace an entry in the collection.</param>
/// <param name="error">An error indicating why applying the operation failed, if applicable.</param>
/// <returns>Returns whether applying the operation succeeded.</returns>
private bool TryApplyTextOperation <TKey, TValue>(TextOperation operation, Func <TKey, bool> hasEntry, Func <TKey, TValue> getEntry, Action <TKey> removeEntry, Action <TKey, TValue> setEntry, out string error)
{
var targetRoot = operation.GetTargetRoot();
switch (targetRoot)
{
case TextOperationTargetRoot.Entries:
{
// validate
if (typeof(TValue) != typeof(string))
{
return(this.Fail($"an '{TextOperationTargetRoot.Entries}' text operation can only be used for string entries. For data model entries, use '{TextOperationTargetRoot.Fields}' instead.", out error));
}
if (operation.Target.Length > 2)
{
return(this.Fail($"an '{TextOperationTargetRoot.Entries}' path must only have one other segment for the property name.", out error));
}
// get key
string rawKey = operation.Target[1].Value;
TKey key;
if (typeof(TKey) == typeof(string))
{
key = (TKey)(object)rawKey;
}
else if (typeof(TKey) == typeof(int))
{
if (!int.TryParse(rawKey, out int intKey))
{
return(this.Fail($"can't use value '{rawKey}' as an entry key because this asset uses numeric keys.", out error));
}
key = (TKey)(object)intKey;
}
else
{
return(this.Fail($"unsupported asset key type '{typeof(TKey).FullName}'.", out error));
}
// get value
string value = hasEntry(key)
? (string)(object)getEntry(key)
: null;
// set value
setEntry(key, (TValue)(object)operation.Apply(value));
}
break;
case TextOperationTargetRoot.Fields:
throw new NotImplementedException("TODO");
default:
return(this.Fail(
targetRoot == null
? $"unknown path root '{operation.Target[0]}'."
: $"path root '{targetRoot}' isn't valid for an {nameof(PatchType.EditMap)} patch",
out error
));
}
error = null;
return(true);
}