1 files changed, 81 insertions, 0 deletions
diff --git a/src/main/kotlin/moe/nea/firmament/commands/dsl.kt b/src/main/kotlin/moe/nea/firmament/commands/dsl.kt
new file mode 100644
index 0000000..5ead624
--- /dev/null
+++ b/src/main/kotlin/moe/nea/firmament/commands/dsl.kt
@@ -0,0 +1,81 @@
+package moe.nea.firmament.commands
+
+import com.mojang.brigadier.arguments.ArgumentType
+import com.mojang.brigadier.builder.ArgumentBuilder
+import com.mojang.brigadier.builder.LiteralArgumentBuilder
+import com.mojang.brigadier.builder.RequiredArgumentBuilder
+import com.mojang.brigadier.context.CommandContext
+import java.lang.reflect.ParameterizedType
+import net.fabricmc.fabric.api.client.command.v2.FabricClientCommandSource
+import moe.nea.firmament.util.iterate
+
+
+typealias DefaultSource = FabricClientCommandSource
+
+
+inline val <T : CommandContext<*>> T.context get() = this
+operator fun <T : Any, C : CommandContext<*>> C.get(arg: TypeSafeArg<T>): T {
+    return arg.get(this)
+}
+
+fun literal(
+    name: String,
+    block: LiteralArgumentBuilder<DefaultSource>.() -> Unit
+): LiteralArgumentBuilder<DefaultSource> =
+    LiteralArgumentBuilder.literal<DefaultSource>(name).also(block)
+
+data class TypeSafeArg<T : Any>(val name: String, val argument: ArgumentType<T>) {
+    val argClass by lazy {
+        argument.javaClass
+            .iterate<Class<in ArgumentType<T>>> {
+                it.superclass
+            }
+            .map {
+                it.genericSuperclass
+            }
+            .filterIsInstance<ParameterizedType>()
+            .find { it.rawType == ArgumentType::class.java }!!
+            .let { it.actualTypeArguments[0] as Class<*> }
+    }
+
+    @JvmName("getWithThis")
+    fun <S> CommandContext<S>.get(): T =
+        get(this)
+
+
+    fun <S> get(ctx: CommandContext<S>): T {
+        return ctx.getArgument(name, argClass) as T
+    }
+}
+
+
+fun <T : Any> argument(
+    name: String,
+    argument: ArgumentType<T>,
+    block: RequiredArgumentBuilder<DefaultSource, T>.(TypeSafeArg<T>) -> Unit
+): RequiredArgumentBuilder<DefaultSource, T> =
+    RequiredArgumentBuilder.argument<DefaultSource, T>(name, argument).also { block(it, TypeSafeArg(name, argument)) }
+
+fun <T : ArgumentBuilder<DefaultSource, T>, AT : Any> T.thenArgument(
+    name: String,
+    argument: ArgumentType<AT>,
+    block: RequiredArgumentBuilder<DefaultSource, AT>.(TypeSafeArg<AT>) -> Unit
+): T = then(argument(name, argument, block))
+
+
+fun <T : ArgumentBuilder<DefaultSource, T>> T.thenLiteral(
+    name: String,
+    block: LiteralArgumentBuilder<DefaultSource>.() -> Unit
+): T =
+    then(literal(name, block))
+
+fun <T : ArgumentBuilder<DefaultSource, T>> T.then(node: ArgumentBuilder<DefaultSource, *>, block: T.() -> Unit): T =
+    then(node).also(block)
+
+fun <T : ArgumentBuilder<DefaultSource, T>> T.thenExecute(block: CommandContext<DefaultSource>.() -> Unit): T =
+    executes {
+        block(it)
+        1
+    }
+
+