package net.pterodactylus.rhynodge.filters.webpages.epicgames

import com.fasterxml.jackson.databind.JsonNode
import net.pterodactylus.rhynodge.Filter
import net.pterodactylus.rhynodge.State
import net.pterodactylus.rhynodge.states.JsonState
import java.time.Instant

class EpicGamesFilter : Filter {

	override fun filter(state: State): State {
		state as? JsonState ?: throw IllegalArgumentException("state must be a JSON state")
		return state.jsonNode.at("/data/Catalog/searchStore/elements").map { gameJson: JsonNode ->
			val title = gameJson.get("title").asText()
			val imageUrl = gameJson.at("/keyImages/1/url").asText()
			val startDate = getPromotionalOfferStartDate(gameJson)
			val endDate = getPromotionalOfferEndDate(gameJson)
			FreeGame(title, imageUrl, startDate, endDate)
		}.let { FreeGamesState(it.toSet()) }
	}

	private fun getPromotionalOfferEndDate(gameJson: JsonNode) = getPromotionalOfferDate(gameJson, "endDate")
	private fun getPromotionalOfferStartDate(gameJson: JsonNode) = getPromotionalOfferDate(gameJson, "startDate")

	private fun getPromotionalOfferDate(gameJson: JsonNode, date: String) = listOf("promotionalOffers", "upcomingPromotionalOffers")
		.map { "/promotions/$it/0/promotionalOffers/0/$date" }
		.map(gameJson::at)
		.filterNot(JsonNode::isMissingNode)
		.map(JsonNode::asText)
		.map(Instant::parse)
		.first()

}