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Diffstat (limited to 'BJC-Utils2/src/main/java/bjc/utils/cli/GenericCommandMode.java')
| -rw-r--r-- | BJC-Utils2/src/main/java/bjc/utils/cli/GenericCommandMode.java | 356 |
1 files changed, 356 insertions, 0 deletions
diff --git a/BJC-Utils2/src/main/java/bjc/utils/cli/GenericCommandMode.java b/BJC-Utils2/src/main/java/bjc/utils/cli/GenericCommandMode.java new file mode 100644 index 0000000..5b35a0b --- /dev/null +++ b/BJC-Utils2/src/main/java/bjc/utils/cli/GenericCommandMode.java @@ -0,0 +1,356 @@ +package bjc.utils.cli; + +import java.util.TreeMap; +import java.util.function.BiConsumer; +import java.util.function.Consumer; + +import bjc.utils.funcdata.FunctionalMap; +import bjc.utils.funcdata.IFunctionalMap; + +/** + * A general command mode, with a customizable set of commands + * + * There is a small set of commands which is handled by default. The first + * is 'list', which lists all the commands the user can input. The second + * is 'alias', which allows the user to bind a new name to a command + * + * @author ben + * + */ +public class GenericCommandMode implements ICommandMode { + private IFunctionalMap<String, ICommand> commandHandlers; + private IFunctionalMap<String, ICommand> defaultHandlers; + + private IFunctionalMap<String, ICommandHelp> helpTopics; + + private BiConsumer<String, String[]> unknownCommandHandler; + + private Consumer<String> errorOutput; + private Consumer<String> normalOutput; + + private String modeName; + + private String customPrompt; + + /** + * Create a new generic command mode + * + * @param normalOutput + * The function to use for normal output + * @param errorOutput + * The function to use for error output + */ + public GenericCommandMode(Consumer<String> normalOutput, + Consumer<String> errorOutput) { + this.normalOutput = normalOutput; + this.errorOutput = errorOutput; + + commandHandlers = new FunctionalMap<>(new TreeMap<>()); + defaultHandlers = new FunctionalMap<>(new TreeMap<>()); + helpTopics = new FunctionalMap<>(new TreeMap<>()); + + defaultHandlers.put("list", new GenericCommand((args) -> { + listCommands(); + + return this; + }, "list\tList available command", + "Lists all of the commands available in this mode," + + " as well as the commands that are valid in any mode.")); + + defaultHandlers.put("alias", new GenericCommand((args) -> { + aliasCommands(args); + + return this; + }, "alias\tAlias one command to another", + "alias gives a command another name it can be invoked by. It is invoked" + + " with two arguments, the name of the command to alias" + + ", and the alias to give that command.")); + + defaultHandlers.put("help", new GenericCommand((args) -> { + if (args == null || args.length == 0) { + // Invoke general help + helpSummary(); + } else { + // Invoke help for a command + helpCommand(args[0]); + } + + return this; + }, "help\tConsult the help system", + "help consults the internal help system." + + " It can be invoked in two ways. Invoking it with no arguments" + + " causes it to print out all the topics you can ask for details on," + + " while invoking it with the name of a topic will print the entry" + + " for that topic")); + + // Add commands handled in a upper layer + defaultHandlers.put("clear", new GenericCommand((args) -> { + errorOutput.accept( + "ERROR: This is a bug. Please report to the developer"); + + return this; + }, "clear\tClear the screen", + "clear clears the screen of all the text on it," + + " and prepares a fresh prompt.")); + + defaultHandlers.put("exit", new GenericCommand((args) -> { + errorOutput.accept( + "ERROR: This is a bug. Please report to the developer"); + + return this; + }, "exit\tExit the game", + "exit first prompts the user to make sure they want to exit," + + " and if they affirm it, it quits the game")); + } + + /** + * Add an alias to an existing command + * + * @param commandName + * The name of the command to add an alias for + * @param aliasName + * The new alias for the command + * + * @throws IllegalArgumentException + * if the specified command doesn't have a bound handler, + * or if the alias name already has a bound value + */ + public void addCommandAlias(String commandName, String aliasName) { + if (commandName == null) { + throw new NullPointerException( + "Command name must not be null"); + } else if (aliasName == null) { + throw new NullPointerException("Alias name must not be null"); + } else if (!commandHandlers.containsKey(commandName)) { + throw new IllegalArgumentException( + "Cannot alias non-existant command '" + commandName + + "'"); + } else if (commandHandlers.containsKey(aliasName)) { + throw new IllegalArgumentException("Cannot bind alias '" + + aliasName + "' to a command with a bound handler"); + } else { + commandHandlers.put(aliasName, + commandHandlers.get(commandName)); + } + } + + /** + * Add a command to this command mode + * + * @param command + * The command to add + * @param handler + * The handler to use for the specified command + * + * @throws IllegalArgumentException + * if the specified command already has a handler + * registered + */ + public void addCommandHandler(String command, ICommand handler) { + if (command == null) { + throw new NullPointerException("Command must not be null"); + } else if (handler == null) { + throw new NullPointerException("Handler must not be null"); + } else if (canHandleCommand(command)) { + throw new IllegalArgumentException("Command " + command + + " already has a handler registered"); + } else { + commandHandlers.put(command, handler); + } + } + + /** + * Add a help topic to this command mode that isn't tied to a command + * + * @param topicName + * The name of the topic + * @param help + * The contents of the topic + */ + public void addHelpTopic(String topicName, ICommandHelp help) { + helpTopics.put(topicName, help); + } + + private void aliasCommands(String[] args) { + if (args.length != 2) { + errorOutput.accept("ERROR: Alias requires two arguments. " + + "The command name, and the alias for that command"); + } else { + String commandName = args[0]; + String aliasName = args[1]; + + if (!canHandleCommand(commandName)) { + errorOutput.accept("ERROR: '" + commandName + + "' is not a valid command."); + } else if (canHandleCommand(aliasName)) { + errorOutput.accept("ERROR: Cannot overwrite command '" + + aliasName + "'"); + } else { + addCommandAlias(commandName, aliasName); + } + } + } + + @Override + public boolean canHandleCommand(String command) { + return commandHandlers.containsKey(command) + || defaultHandlers.containsKey(command); + } + + @Override + public String getCustomPrompt() { + if (customPrompt != null) { + return customPrompt; + } + + return ICommandMode.super.getCustomPrompt(); + } + + @Override + public String getName() { + if (modeName != null) { + return modeName; + } + + return ICommandMode.super.getName(); + } + + private void helpCommand(String commandName) { + if (commandHandlers.containsKey(commandName)) { + normalOutput.accept("\n" + commandHandlers.get(commandName) + .getHelp().getDescription()); + } else if (defaultHandlers.containsKey(commandName)) { + normalOutput.accept("\n" + defaultHandlers.get(commandName) + .getHelp().getDescription()); + } else if (helpTopics.containsKey(commandName)) { + normalOutput.accept( + "\n" + helpTopics.get(commandName).getDescription()); + } else { + errorOutput + .accept("ERROR: I'm sorry, but there is no help available for '" + + commandName + "'"); + } + } + + private void helpSummary() { + normalOutput.accept( + "Help topics for this command mode are as follows:\n"); + if (commandHandlers.getSize() > 0) { + commandHandlers.forEachValue((command) -> { + normalOutput.accept( + "\t" + command.getHelp().getSummary() + "\n"); + }); + } else { + normalOutput.accept("\tNone available\n"); + } + + normalOutput.accept( + "\nHelp topics available in all command modes are as follows\n"); + if (defaultHandlers.getSize() > 0) { + defaultHandlers.forEachValue((command) -> { + normalOutput.accept( + "\t" + command.getHelp().getSummary() + "\n"); + }); + } else { + normalOutput.accept("\tNone available\n"); + } + + normalOutput.accept( + "\nHelp topics not associated with a command are as follows\n"); + if (helpTopics.getSize() > 0) { + helpTopics.forEachValue((topic) -> { + normalOutput.accept("\t" + topic.getSummary() + "\n"); + }); + } else { + normalOutput.accept("\tNone available\n"); + } + } + + private void listCommands() { + normalOutput.accept( + "The available commands for this mode are as follows:\n"); + + commandHandlers.keyList().forEach((commandName) -> { + normalOutput.accept("\t" + commandName); + }); + + normalOutput.accept( + "\nThe following commands are available in all modes:\n"); + + defaultHandlers.keyList().forEach((commandName) -> { + normalOutput.accept("\t" + commandName); + }); + + normalOutput.accept("\n"); + } + + @Override + public ICommandMode processCommand(String command, String[] args) { + normalOutput.accept("\n"); + + if (defaultHandlers.containsKey(command)) { + return defaultHandlers.get(command).getHandler().handle(args); + } else if (commandHandlers.containsKey(command)) { + return commandHandlers.get(command).getHandler().handle(args); + } else { + if (args != null) { + errorOutput.accept("ERROR: Unrecognized command " + command + + String.join(" ", args)); + } else { + errorOutput + .accept("ERROR: Unrecognized command " + command); + } + + if (unknownCommandHandler == null) { + throw new UnsupportedOperationException( + "Command " + command + " is invalid."); + } + + unknownCommandHandler.accept(command, args); + } + + return this; + } + + /** + * Set the custom prompt for this mode + * + * @param prompt + * The custom prompt for this mode, or null to disable the + * custom prompt + */ + public void setCustomPrompt(String prompt) { + customPrompt = prompt; + } + + /** + * Set the name of this mode + * + * @param name + * The desired name of this mode, or null to use the default + * name + */ + public void setModeName(String name) { + modeName = name; + } + + /** + * Set the handler to use for unknown commands + * + * @param handler + * The handler to use for unknown commands + */ + public void setUnknownCommandHandler( + BiConsumer<String, String[]> handler) { + if (handler == null) { + throw new NullPointerException("Handler must not be null"); + } + + unknownCommandHandler = handler; + } + + @Override + public boolean useCustomPrompt() { + return customPrompt != null; + } +}
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