Add custom args parser to allow spaces in arguments

Fixes #96 where worlds with spaces could not be
used with chunkmaster.

Signed-off-by: trivernis <trivernis@protonmail.com>

src/main/kotlin/net/trivernis/chunkmaster/commands/CommandChunkmaster.kt

@@ -1,6 +1,7 @@
 package net.trivernis.chunkmaster.commands
 
 import net.trivernis.chunkmaster.Chunkmaster
+import net.trivernis.chunkmaster.lib.ArgParser
 import net.trivernis.chunkmaster.lib.Subcommand
 import org.bukkit.Server
 import org.bukkit.command.Command
@@ -11,6 +12,7 @@ import org.bukkit.command.TabCompleter
 class CommandChunkmaster(private val chunkmaster: Chunkmaster, private val server: Server) : CommandExecutor,
     TabCompleter {
     private val commands = HashMap<String, Subcommand>()
+    private val argParser = ArgParser()
 
     init {
         registerCommands()
@@ -36,7 +38,9 @@ class CommandChunkmaster(private val chunkmaster: Chunkmaster, private val serve
     /**
      * /chunkmaster command to handle all commands
      */
-    override fun onCommand(sender: CommandSender, command: Command, label: String, args: Array<out String>): Boolean {
+    override fun onCommand(sender: CommandSender, command: Command, label: String, bukkitArgs: Array<out String>): Boolean {
+        val args = argParser.parseArguments(bukkitArgs.joinToString(" "))
+
         if (args.isNotEmpty()) {
             if (sender.hasPermission("chunkmaster.${args[0].toLowerCase()}")) {
                 return if (commands.containsKey(args[0])) {

src/main/kotlin/net/trivernis/chunkmaster/lib/ArgParser.kt

@@ -0,0 +1,77 @@
+package net.trivernis.chunkmaster.lib
+
+/**
+ * Better argument parser for command arguments
+ */
+class ArgParser {
+    private var input = ""
+    private var position = 0
+    private var currentChar = ' '
+
+    /**
+     * Parses arguments from a string and respects quotes
+     */
+    fun parseArguments(arguments: String): List<String> {
+        if (arguments.isEmpty()) {
+            return emptyList()
+        }
+
+        input = arguments
+        position = 0
+        currentChar = input[position]
+        val args = ArrayList<String>()
+        var arg = ""
+
+        while (!endReached()) {
+            nextCharacter()
+
+            if (currentChar.isWhitespace()) {
+              if (arg.isNotBlank()) {
+                  args.add(arg)
+              }
+              arg = ""
+            } else if (currentChar == '"') {
+                if (arg.isNotBlank()) {
+                    args.add(arg)
+                }
+                arg = parseString()
+                if (arg.isNotBlank()) {
+                    args.add(arg)
+                }
+                arg = ""
+            } else {
+                arg += currentChar
+            }
+        }
+        if (arg.isNotBlank()) {
+            args.add(arg)
+        }
+        return args
+    }
+
+    /**
+     * Parses an enquoted string
+     */
+    private fun parseString(): String {
+        var output = ""
+
+        while (!endReached()) {
+            nextCharacter()
+            if (currentChar == '"') {
+                break
+            }
+            output += currentChar
+        }
+        return output
+    }
+
+    private fun nextCharacter() {
+        if (!endReached()) {
+            currentChar = input[position++]
+        }
+    }
+
+    private fun endReached(): Boolean {
+        return position >= input.length
+    }
+}

src/test/kotlin/net/trivernis/chunkmaster/lib/ArgParserTest.kt

@@ -0,0 +1,49 @@
+package net.trivernis.chunkmaster.lib
+
+import io.kotest.matchers.shouldBe
+import org.junit.Test
+
+class ArgParserTest {
+    var argParser = ArgParser()
+
+    @Test
+    fun `it parses arguments`() {
+        argParser.parseArguments("first second third forth").shouldBe(listOf("first", "second", "third", "forth"))
+    }
+
+    @Test
+    fun `it parses quoted arguments as one argument`() {
+        argParser.parseArguments("first \"second with space\" third").shouldBe(listOf("first", "second with space", "third"))
+        argParser.parseArguments("\"first\" \"second\" \"third\"").shouldBe(listOf("first", "second", "third"))
+    }
+
+    @Test
+    fun `it parses single arguments`() {
+        argParser.parseArguments("one").shouldBe(listOf("one"))
+        argParser.parseArguments("\"one\"").shouldBe(listOf("one"))
+    }
+
+    @Test
+    fun `it parses no arguments`() {
+        argParser.parseArguments("").shouldBe(emptyList())
+    }
+
+    @Test
+    fun `it parses just whitespace as no arguments`() {
+        argParser.parseArguments("     ").shouldBe(emptyList())
+        argParser.parseArguments("\t\t").shouldBe(emptyList())
+    }
+
+    @Test
+    fun `it parses arguments with weird whitespace`() {
+        argParser.parseArguments("   first      second  \t third \n forth    ").shouldBe(listOf("first", "second", "third", "forth"))
+    }
+
+    @Test
+    fun `it deals predictable with malformed input`() {
+        argParser.parseArguments("first \"second third fourth").shouldBe(listOf("first", "second third fourth"))
+        argParser.parseArguments("\"first second \"third\" fourth").shouldBe(listOf("first second ", "third", " fourth"))
+        argParser.parseArguments("first second third fourth\"").shouldBe(listOf("first", "second", "third", "fourth"))
+        argParser.parseArguments("\"").shouldBe(emptyList())
+    }
+}

src/test/kotlin/net/trivernis/chunkmaster/lib/LanguageManagerTest.kt

@@ -1,8 +1,8 @@
-package net.trivernis.chunkmaster
+package net.trivernis.chunkmaster.lib
 import io.kotest.matchers.string.shouldNotBeEmpty
 import io.mockk.every
 import io.mockk.mockk
-import net.trivernis.chunkmaster.lib.LanguageManager
+import net.trivernis.chunkmaster.Chunkmaster
 import org.bukkit.configuration.file.FileConfiguration
 import org.junit.Test