Eden's Stages manager

Stages.kt

package modules.dialogue

/**
 * @author Jire
 */
class Stages(val dialogue: Dialogue) {
	
	companion object {
		const val START_STAGE = 1
		const val END_STAGE = -1
	}
	
	val START_STAGE = Companion.START_STAGE // for no-import use in handles
	val END_STAGE = Companion.END_STAGE // for no-import use in handles
	
	private val idToStage = HashMap<Int, Stage>()
	
	fun defineStage(id: Int, stage: Stage) {
		idToStage.put(id, stage)
	}
	
	fun stageFor(id: Int) = idToStage[id]
	
	operator inline fun <R> Int.invoke(crossinline handle: Stage.() -> R) {
		if (this < 1) throw IllegalArgumentException("You can only define stages one through infinity!")
		if (stageFor(this) != null) throw IllegalStateException("Stage $this is already defined!")
		
		val stage = Stage(this)
		stage.next = {
			val result = stage.handle()
			
			if (result is Int) result
			else dialogue.stage + 1 // the new stage is our current stage + 1
		}
		
		defineStage(this, stage)
	}
	
	// MISC MACROS
	
	operator fun String.minus(next: String) = ArrayList<String>(5).apply { add(this@minus); add(next) }
	operator fun MutableList<String>.minus(next: String) = apply { add(next) }
	
	inner class StageMacro(val strings: List<String>, val stage: Int)
	
	operator fun MutableList<String>.minus(stage: Int) = StageMacro(this, stage)
	operator fun String.minus(stage: Int) = StageMacro(listOf(this), stage)
	
	// NPC MACROS
	
	fun Int.npc(vararg lines: String) = invoke { dialogue.npc(*lines) }
	fun Int.npc(vararg lines: String, nextStage: Int) = invoke { dialogue.npc(*lines); nextStage }
	
	infix fun Int.npc(lines: List<String>) = npc(*lines.toTypedArray())
	infix fun Int.npc(message: String) = npc(message.split("\n"))
	infix fun Int.npc(macro: StageMacro) = npc(*macro.strings.toTypedArray(), nextStage = macro.stage)
	
	// PLAYER MACROS
	fun Int.player(vararg lines: String) = invoke { dialogue.player(*lines) }
	fun Int.player(vararg lines: String, nextStage: Int) = invoke { dialogue.player(*lines); nextStage }
	
	infix fun Int.player(lines: List<String>) = player(*lines.toTypedArray())
	infix fun Int.player(message: String) = player(message.split("\n"))
	infix fun Int.player(macro: StageMacro) = player(*macro.strings.toTypedArray(), nextStage = macro.stage)
	
	// OPTION MACROS
	fun Int.options(vararg options: String) = invoke { dialogue.options(*options) }
	fun Int.options(vararg options: String, nextStage: Int) = invoke { dialogue.options(*options); nextStage }
	
	infix fun Int.options(options: List<String>) = options(*options.toTypedArray())
	infix fun Int.options(options: String) = options(options.split("\n"))
	infix fun Int.options(macro: StageMacro) = options(*macro.strings.toTypedArray(), nextStage = macro.stage)
	
}