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/*
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package org.spongepowered.api.command.parameter.managed;
import net.kyori.adventure.text.Component;
import org.checkerframework.checker.nullness.qual.Nullable;
import org.spongepowered.api.command.CommandCompletion;
import org.spongepowered.api.command.CommandExecutor;
import org.spongepowered.api.command.exception.ArgumentParseException;
import org.spongepowered.api.command.parameter.ArgumentReader;
import org.spongepowered.api.command.parameter.CommandContext;
import org.spongepowered.api.command.parameter.Parameter;
import java.util.List;
import java.util.Optional;
/**
* A value parameter modifier is an alternative to attempting to create an
* element that extends/wraps around a {@link ValueParameter}, particularly
* those that are provided by Sponge on behalf of Minecraft or other
* underlying implementation.
*
* The primary intention of a modifier is to enable custom filtering logic
* on in-built parameters so that plugins can refine the user experience when
* using their commands while retaining most of the properties of the underlying
* parameter. In general, plugins should not use modifiers on
* their own {@link ValueParameter value parameters} or associated classes.
* Further, modifiers are not designed to perform any
* post-processing on any parsed elements, they should generally only be used to
* validate or filter results and completions - post-processing should be
* performed in the {@link CommandExecutor command's exectuor} instead, as by
* this point you know that your command has been selected.
*
* These modifier methods are provided the same information as the original
* parameter, along with the result of the original parameter - that is, these
* modifiers run after the associated parameter has run. The
* main takeaway here is that modifiers cannot add new entries
* to the parameter, only modify what they return and filter out entries that
* are not supported by your operation.
*
* Modifiers are not designed to transform the returned type
* - this is to maintain the integrity of the key typing and to discourage
* additional logic in parameter parsing that should actually exist in the
* {@link CommandExecutor} of the command instead.
*
* Users of modifiers should consider the following when modifying the
* result:
*
*
* - Any supplied parameters may have been modified by the associated
* parameter that this is modifying, and are not snapshots from before.
* - The {@link ArgumentReader} is immutable. This is to
* prevent accidental continued parsing. If you want to use a modifier to
* further parse the input string based on the result of chained parameter,
* create a custom {@link ValueParameter} that follows on from the node in
* question instead - the result of this parse will be available in the
* {@link CommandContext.Builder} in later nodes.
* - Modifiers may choose to not return a value and
* instead add to the {@link CommandContext.Builder} directly. While this is
* permissible, do not be tempted to use modifiers as a way to perform logic
* this is not directly related to parsing a string to avoid unnecessary
* processing that may not be used if a later node fails to parse and this
* node's result is discarded.
* - Modifiers cannot prevent the chained parameter from throwing an
* exception, in the case that they do so this modifier will not be called.
* Instead, add a second {@link ValueParser} to the parameter, and account
* for this in your modifier.
* - The use of a modifier will require that any completion requests are
* sent to the server, regardless of whether completions are actually
* modified. If completions are not being modified, consider whether it
* would be better to process the parsed result in the body of your executor
* instead.
*
*
* With all this in mind, modifiers should be used sparingly, preferring the
* use of other constructs when at all possible.
*/
public interface ValueParameterModifier {
/**
* Modifies the result of {@link ValueParser#parseValue(Parameter.Key,
* ArgumentReader.Mutable, CommandContext.Builder) the chained parameter's
* parse result}.
*
* @param parameterKey The target {@link Parameter.Key} to fill in the
* context
* @param reader The {@link ArgumentReader.Immutable} that may have been
* advanced by the parser
* @param context The {@link CommandContext.Builder} that may have been
* modified by the parser
* @param value The value returned by the parser, if any
* @return The value to associate with the {@code parameterKey}
* @throws ArgumentParseException if the modifier wishes to halt processing
* of this element
*/
Optional modifyResult(
Parameter.Key parameterKey,
ArgumentReader.Immutable reader,
CommandContext.Builder context,
@Nullable T value) throws ArgumentParseException;
/**
* Modifies the result of {@link ValueCompleter#complete(CommandContext,
* String) the chained parameter's completions}.
*
* @param context The {@link CommandContext}
* @param currentInput The input that suggestions are built from
* @param completions The completions suggested by the chained parameter
* @return The modified completions
*/
default List modifyCompletion(
final CommandContext context, final String currentInput, final List completions) {
return completions;
}
/**
* Modifies the message provided in a {@link ArgumentParseException} if the
* modified {@link ValueParser} throws this exception.
*
* @param exceptionMessage The message provided by the {@link ValueParser}
* @return The modified message, or the parameter if it is not to be modified.
*/
default @Nullable Component modifyExceptionMessage(final @Nullable Component exceptionMessage) {
return exceptionMessage;
}
}