package dev.cobblesurvival.selftest

import com.cobblemon.mod.common.api.spawning.CobblemonSpawnPools
import com.cobblemon.mod.common.api.spawning.detail.PokemonSpawnDetail
import dev.cobblesurvival.progress.QuestEvents
import dev.cobblesurvival.zone.Zones
import net.minecraft.gametest.framework.GameTestAssertException
import net.minecraft.resources.ResourceLocation
import net.minecraft.world.item.ItemStack
import net.minecraft.world.level.levelgen.Heightmap
import java.util.function.Consumer

/**
 * Roadmap Phase 8 (Adrian, 2026-11-03): the add-ons the quest book and JEI lean on work with the pack. Read by
 * reflection, so the companion mod needs neither at compile time.
 */
object QuestTests {
    fun all() = listOf(
        SelfTestCase("quests_have_cobblemon_tasks", 20, ::cobblemonTasks),
        SelfTestCase("jei_addon_shows_island_spawns", 20, ::addonSpawns),
        SelfTestCase("quest_book_loads", 20, ::bookLoads),
        SelfTestCase("quest_events_mark_zones", 200, ::zoneEvent),
    )

    /** At least this many quests in the book (docs/quests.yaml: 74 on 2026-11-03). */
    private const val MIN_QUESTS = 70

    private fun field(obj: Any, name: String): Any? {
        var c: Class<*>? = obj.javaClass
        while (c != null) {
            runCatching { return c.getDeclaredField(name).apply { isAccessible = true }.get(obj) }
            c = c.superclass
        }
        throw GameTestAssertException("${obj.javaClass.simpleName} has no field $name")
    }

    /**
     * FTB Quests loaded the generated book (tools/quests.py): enough quests, flexible progression, and every task
     * understood: no unknown task type, every item exists, every advancement exists on the server.
     */
    private fun bookLoads(s: Scenario) {
        val file = Class.forName("dev.ftb.mods.ftbquests.quest.ServerQuestFile").getField("INSTANCE").get(null)
            ?: throw GameTestAssertException("FTB Quests has no server quest file")
        val quests = mutableListOf<Any>()
        file.javaClass.getMethod("forAllQuests", Consumer::class.java).invoke(file, Consumer<Any> { quests += it })
        s.check(quests.size >= MIN_QUESTS) { "FTB Quests loaded ${quests.size} quests, not the book's $MIN_QUESTS or more" }
        s.check(field(file, "progressionMode").toString().equals("flexible", ignoreCase = true)) { "the book isn't in flexible mode" }
        val problems = mutableListOf<String>()
        for (quest in quests) {
            for (task in quest.javaClass.getMethod("getTasks").invoke(quest) as Collection<*>) {
                when (task!!.javaClass.simpleName) {
                    "CustomTask" -> problems += "unknown task type in quest ${quest}"
                    "ItemTask" -> if ((field(task, "itemStack") as ItemStack).isEmpty) problems += "an item task with no item in $quest"
                    "AdvancementTask" -> {
                        val id = field(task, "advancement") as ResourceLocation
                        if (s.level.server.advancements.get(id) == null) problems += "no advancement $id"
                    }
                }
            }
        }
        s.check(problems.isEmpty()) { problems.take(5).joinToString("; ") }
        s.helper.succeed()
    }

    /** Walking into a zone marks the hidden advancement its "reach the zone" quest checks (progress/QuestEvents.kt). */
    private fun zoneEvent(s: Scenario) {
        val sample = Zones.samples["button_isle"] ?: throw GameTestAssertException("no sample point for Button Isle")
        val player = s.player()
        s.helper.startSequence()
            .thenExecute {
                s.level.getChunk(sample.x shr 4, sample.z shr 4)
                s.moveTo(player, sample.x + 0.5, s.level.getHeight(Heightmap.Types.MOTION_BLOCKING_NO_LEAVES, sample.x, sample.z).toDouble(), sample.z + 0.5)
            }
            .thenWaitUntil { s.check(QuestEvents.done(player, "zone/button_isle")) { "reaching Button Isle didn't mark zone/button_isle" } }
            .thenSucceed()
    }

    /** Cobblemon Quests Reloaded adds its task type (catch, defeat, evolve, level up, ...) to FTB Quests. */
    private fun cobblemonTasks(s: Scenario) {
        val types = Class.forName("dev.ftb.mods.ftbquests.quest.task.TaskTypes").getField("TYPES").get(null) as Map<*, *>
        s.check(types.keys.any { it.toString() == "cobblemon_tasks:cobblemon_task" }) { "FTB Quests has no Cobblemon task type: ${types.keys}" }
        s.helper.succeed()
    }

    /**
     * Cobblemon Info for REI/JEI/EMI shows what the pack's own spawn pools say (Adrian: check that its spawn info is
     * right for the pack): every entry it lists is one of the zone pools' entries, at the zone's levels, and it lists
     * all of them. It can't show the zone itself, only the zone's biomes (docs/design.md, Phase 8).
     */
    private fun addonSpawns(s: Scenario) {
        val loader = Class.forName("com.cobbledex.SpawnDataLoader")
        val shown = (loader.getMethod("loadFromRuntime").invoke(loader.getField("INSTANCE").get(null)) as Map<*, *>).values.flatMap { it as List<*> }
        fun field(info: Any?, name: String) = info!!.javaClass.getMethod("get" + name.replaceFirstChar { it.uppercase() }).invoke(info) as String
        val ours = CobblemonSpawnPools.WORLD_SPAWN_POOL.details.filterIsInstance<PokemonSpawnDetail>().associateBy { it.id }
        s.check(shown.isNotEmpty()) { "the JEI add-on shows no spawns" }
        val strangers = shown.map { field(it, "id") }.filter { it !in ours }
        s.check(strangers.isEmpty()) { "the JEI add-on shows ${strangers.size} spawns the pack doesn't have, e.g. ${strangers.take(5)}" }
        val wrongLevels = shown.filter { info ->
            val zone = Zones.byId[field(info, "id").substringBefore('-')] ?: return@filter true
            val (low, high) = field(info, "levelRange").split("-").map { it.toInt() }
            low < zone.minLevel || high > zone.maxLevel
        }
        s.check(wrongLevels.isEmpty()) { "the JEI add-on shows levels outside the zone's band: ${wrongLevels.take(5).map { field(it, "id") + " " + field(it, "levelRange") }}" }
        val missing = ours.keys - shown.map { field(it, "id") }.toSet()
        s.check(missing.isEmpty()) { "the JEI add-on leaves out ${missing.size} of the pack's spawns, e.g. ${missing.take(5)}" }
        s.helper.succeed()
    }
}