Simplifications

src/main/kotlin/moe/kageru/kagebot/MessageUtil.kt

@@ -6,24 +6,17 @@ import org.javacord.api.entity.message.Message
 import org.javacord.api.entity.message.MessageAuthor
 import org.javacord.api.entity.message.Messageable
 import org.javacord.api.entity.message.embed.EmbedBuilder
-import org.javacord.api.entity.user.User
 import java.util.concurrent.CompletableFuture
 
 object MessageUtil {
-    fun mention(user: MessageAuthor): String {
-        return "<@${user.id}>"
-    }
-
-    fun mention(user: User): String {
-        return "<@${user.id}>"
-    }
+    fun MessageAuthor.mention() = "<@$id>"
 
     fun withEmbed(op: EmbedBuilder.() -> Unit): EmbedBuilder {
-        val builder = EmbedBuilder()
-        Config.server.icon.ifPresent { builder.setThumbnail(it) }
-        builder.setColor(SystemSpec.color)
-        builder.op()
-        return builder
+        return EmbedBuilder().apply {
+            Config.server.icon.ifPresent { setThumbnail(it) }
+            setColor(SystemSpec.color)
+            op()
+        }
     }
 
     fun Messageable.sendEmbed(op: EmbedBuilder.() -> Unit) {

src/main/kotlin/moe/kageru/kagebot/command/Command.kt

@@ -4,7 +4,7 @@ import com.fasterxml.jackson.annotation.JsonProperty
 import moe.kageru.kagebot.Globals
 import moe.kageru.kagebot.Log
 import moe.kageru.kagebot.MessageUtil
-import moe.kageru.kagebot.Util.applyIf
+import moe.kageru.kagebot.MessageUtil.mention
 import moe.kageru.kagebot.config.Config
 import moe.kageru.kagebot.features.MessageFeature
 import org.javacord.api.entity.message.MessageAuthor
@@ -49,22 +49,12 @@ class Command(
     }
 
     private fun respond(author: MessageAuthor, response: String) =
-        response.applyIf(response.contains(AUTHOR_PLACEHOLDER)) {
-            it.replace(AUTHOR_PLACEHOLDER, MessageUtil.mention(author))
-        }
+        response.replace(AUTHOR_PLACEHOLDER, author.mention())
 }
 
 @Suppress("unused")
-enum class MatchType {
-    PREFIX {
-        override fun matches(message: String, command: Command) = message.startsWith(command.trigger, ignoreCase = true)
-    },
-    CONTAINS {
-        override fun matches(message: String, command: Command) = message.contains(command.trigger, ignoreCase = true)
-    },
-    REGEX {
-        override fun matches(message: String, command: Command) = command.regex!!.matches(message)
-    };
-
-    abstract fun matches(message: String, command: Command): Boolean
+enum class MatchType(val matches: (String, Command) -> Boolean) {
+    PREFIX({ message, command -> message.startsWith(command.trigger, ignoreCase = true) }),
+    CONTAINS({ message, command -> message.contains(command.trigger, ignoreCase = true) }),
+    REGEX({ message, command -> command.regex!!.matches(message) });
 }

src/main/kotlin/moe/kageru/kagebot/config/ConfigSpecs.kt

@@ -23,5 +23,5 @@ object CommandSpec : ConfigSpec(prefix = "") {
 }
 
 object FeatureSpec : ConfigSpec(prefix = "") {
-    val features by optional(Features.DEFAULT, name = "feature")
+    val features by optional(Features(), name = "feature")
 }

src/main/kotlin/moe/kageru/kagebot/extensions/ArrowExtensions.kt

@@ -13,10 +13,10 @@ fun <L, R> Either<L, R>.on(op: (R) -> Unit): Either<L, R> {
 
 fun <T> Either<*, T>.unwrap(): T = getOrElse { error("Attempted to unwrap Either.left") }
 
-fun <A, B, C, A2, F> Tuple3<A, B, C>.mapFirst(AP: Functor<F>, op: (A) -> Kind<F, A2>) = let { (a, b, c) ->
+inline fun <A, B, C, A2, F> Tuple3<A, B, C>.mapFirst(AP: Functor<F>, op: (A) -> Kind<F, A2>) = let { (a, b, c) ->
     AP.run { op(a).map { Tuple3(it, b, c) } }
 }
 
-fun <A, B, C, B2, F> Tuple3<A, B, C>.mapSecond(AP: Functor<F>, op: (B) -> Kind<F, B2>) = let { (a, b, c) ->
+inline fun <A, B, C, B2, F> Tuple3<A, B, C>.mapSecond(AP: Functor<F>, op: (B) -> Kind<F, B2>) = let { (a, b, c) ->
     AP.run { op(b).map { Tuple3(a, it, c) } }
 }

src/main/kotlin/moe/kageru/kagebot/features/Features.kt

@@ -1,6 +1,10 @@
 package moe.kageru.kagebot.features
 
-class Features(val welcome: WelcomeFeature?, val timeout: TimeoutFeature?, vc: TempVCFeature = TempVCFeature(null)) {
+class Features(
+    val welcome: WelcomeFeature? = null,
+    val timeout: TimeoutFeature? = null,
+    vc: TempVCFeature = TempVCFeature(null)
+) {
     private val debug = DebugFeature()
     private val help = HelpFeature()
     private val getConfig = GetConfigFeature()
@@ -19,8 +23,4 @@ class Features(val welcome: WelcomeFeature?, val timeout: TimeoutFeature?, vc: T
 
     fun findByString(feature: String) = featureMap[feature]
     fun eventFeatures() = all.filterIsInstance<EventFeature>()
-
-    companion object {
-        val DEFAULT = Features(null, null)
-    }
 }

src/main/kotlin/moe/kageru/kagebot/features/WelcomeFeature.kt

@@ -3,8 +3,8 @@ package moe.kageru.kagebot.features
 import moe.kageru.kagebot.Log
 import moe.kageru.kagebot.MessageUtil
 import moe.kageru.kagebot.Util
-import moe.kageru.kagebot.Util.checked
 import moe.kageru.kagebot.Util.asOption
+import moe.kageru.kagebot.Util.checked
 import moe.kageru.kagebot.extensions.unwrap
 import org.javacord.api.DiscordApi
 import org.javacord.api.entity.channel.TextChannel
@@ -31,7 +31,7 @@ class WelcomeFeature(
         // If the user disabled direct messages, try the fallback (if defined)
         if (message.asOption().isEmpty() && hasFallback()) {
             fallbackChannel!!.sendMessage(
-                fallbackMessage!!.replace("@@", MessageUtil.mention(event.user))
+                fallbackMessage!!.replace("@@", event.user.mentionTag)
             )
         }
     }