Merge pull request nus-cs2103-AY1718S2#43 from jasmoon/master

Enhance help/man command

docs/AboutUs.adoc

@@ -19,7 +19,7 @@ Responsibilities: Logic
 
 '''
 
-=== Jasmond Toh
+=== Jasmund Toh
 
 {empty}[http://github.com/jasmoon[github]]
 

docs/UserGuide.adoc

@@ -56,9 +56,18 @@ e.g. typing *`help`* and pressing kbd:[Enter] will open the help window.
 * Parameters can be in any order e.g. if the command specifies `n/NAME p/PHONE_NUMBER`, `p/PHONE_NUMBER n/NAME` is also acceptable.
 ====
 
-=== Viewing help : `help`
 
-Format: `help`
+=== Viewing help : `help` or `man`
+
+Shows the help menu or help for the `COMMAND_WORD` requested.
+
+Format: `help`, `help COMMAND_WORD`, `man` or `man COMMAND_WORD`
+
+Examples:
+
+* `help`
+
+* `man add`
 
 === Adding a person: `add`
 

src/main/java/seedu/address/logic/commands/HelpCommand.java

@@ -4,20 +4,59 @@
 import seedu.address.commons.events.ui.ShowHelpRequestEvent;
 
 /**
- * Format full help instructions for every command for display.
+ * Format full help instructions for every command for display or command requested
  */
 public class HelpCommand extends Command {
 
+    public static final String COMMAND_ALIAS = "man";
     public static final String COMMAND_WORD = "help";
 
-    public static final String MESSAGE_USAGE = COMMAND_WORD + ": Shows program usage instructions.\n"
-            + "Example: " + COMMAND_WORD;
+    public static final String MESSAGE_USAGE = COMMAND_WORD + "/" + COMMAND_ALIAS + ": "
+            + "Shows program usage instructions.\n"  + "Example: " + COMMAND_WORD;
 
     public static final String SHOWING_HELP_MESSAGE = "Opened help window.";
+    private String commandRequest = null;
+
+
+    //@@author jasmoon
+    public HelpCommand()    {
+    }
+
+    public HelpCommand(String args) {
+        commandRequest = args.trim();
+    }
 
     @Override
     public CommandResult execute() {
-        EventsCenter.getInstance().post(new ShowHelpRequestEvent());
-        return new CommandResult(SHOWING_HELP_MESSAGE);
+        if (commandRequest == null)   {
+            EventsCenter.getInstance().post(new ShowHelpRequestEvent());
+            return new CommandResult(SHOWING_HELP_MESSAGE);
+
+        } else   {
+            switch(commandRequest) {
+
+            case AddCommand.COMMAND_WORD:
+                return new CommandResult(AddCommand.MESSAGE_USAGE);
+
+            case EditCommand.COMMAND_WORD:
+                return new CommandResult(EditCommand.MESSAGE_USAGE);
+
+            case SelectCommand.COMMAND_WORD:
+                return new CommandResult(SelectCommand.MESSAGE_USAGE);
+
+            case DeleteCommand.COMMAND_WORD:
+                return new CommandResult(DeleteCommand.MESSAGE_USAGE);
+
+            case FindCommand.COMMAND_WORD:
+                return new CommandResult(FindCommand.MESSAGE_USAGE);
+
+            default:
+                return new CommandResult(MESSAGE_USAGE);
+            }
+        }
+    }
+
+    public String getCommandRequest() {
+        return commandRequest;
     }
 }

src/main/java/seedu/address/logic/parser/AddressBookParser.java

@@ -79,7 +79,10 @@ public Command parseCommand(String userInput) throws ParseException {
             return new ExitCommand();
 
         case HelpCommand.COMMAND_WORD:
-            return new HelpCommand();
+            return new HelpCommandParser().parse(arguments);
+
+        case HelpCommand.COMMAND_ALIAS:
+            return new HelpCommandParser().parse(arguments);
 
         case UndoCommand.COMMAND_WORD:
             return new UndoCommand();

src/main/java/seedu/address/logic/parser/HelpCommandParser.java

@@ -0,0 +1,60 @@
+package seedu.address.logic.parser;
+
+import java.util.ArrayList;
+
+import seedu.address.logic.commands.HelpCommand;
+import seedu.address.logic.parser.exceptions.ParseException;
+
+
+
+//@@author jasmoon
+
+/**
+ * Parses input arguments and create a new HelpCommand object.
+ */
+public class HelpCommandParser implements Parser<HelpCommand> {
+
+    public final ArrayList<String> availableCommands;
+
+    /**
+     * HelpCommandParser constructor - creates an ArrayList which contains all commands open to the help function.
+     */
+    public HelpCommandParser()  {
+        availableCommands = new ArrayList<String>();
+        availableCommands.add("add");
+        availableCommands.add("delete");
+        availableCommands.add("edit");
+        availableCommands.add("find");
+        availableCommands.add("select");
+    }
+
+    /**
+     * Parses the given {@code String} of arguments in the context of the HelpCommand
+     * and returns an HelpCommand object for execution.
+     * @throws ParseException if the user input does not conform the expected format
+     */
+
+    public HelpCommand parse(String args) throws ParseException {
+
+        String commandRequest = args.trim();
+        if (commandRequest.length() == 0) {
+            return new HelpCommand();
+        } else {
+            if (availableCommands.contains(commandRequest)) {
+                return new HelpCommand(args);
+            } else {
+                throw new ParseException(formInvalidMessage(commandRequest));
+            }
+        }
+    }
+
+    /**
+     *
+     * @param commandRequest
+     * @return String message for invalid command request.
+     */
+    private String formInvalidMessage(String commandRequest)    {
+        return "Help for '" + commandRequest + "' is unknown or not available.";
+    }
+}
+

src/test/java/seedu/address/logic/parser/AddressBookParserTest.java

@@ -92,8 +92,19 @@ public void parseCommand_find() throws Exception {
 
     @Test
     public void parseCommand_help() throws Exception {
+
+        //@@author jasmoon
         assertTrue(parser.parseCommand(HelpCommand.COMMAND_WORD) instanceof HelpCommand);
-        assertTrue(parser.parseCommand(HelpCommand.COMMAND_WORD + " 3") instanceof HelpCommand);
+        assertTrue(parser.parseCommand(HelpCommand.COMMAND_ALIAS + " find") instanceof HelpCommand);
+        try {
+            parser.parseCommand(HelpCommand.COMMAND_WORD + " 3");
+            fail("The expected ParseException was not thrown");
+        } catch (ParseException pe) {
+            assertEquals("Help for '3' is unknown or not available.", pe.getMessage());
+        }
+        //need help with this test
+        //HelpCommand command = (HelpCommand) parser.parseCommand(HelpCommand.COMMAND_WORD + " find");
+        //assertEquals(new HelpCommand("find").execute(), command.execute());
     }
 
     @Test