CustomAnvil/src/main/kotlin/io/delilaheve/util/ItemUtil.kt

package io.delilaheve.util

import org.bukkit.Material.ENCHANTED_BOOK
import org.bukkit.inventory.ItemStack
import org.bukkit.inventory.meta.Damageable
import xyz.alexcrea.cuanvil.enchant.CAEnchantment
import kotlin.math.ceil
import kotlin.math.max
import kotlin.math.min

/**
 * Item manipulation utilities
 */
object ItemUtil {

    /**
     * Check if this [ItemStack] is an [ENCHANTED_BOOK]
     */
    fun ItemStack.isEnchantedBook() = type == ENCHANTED_BOOK

    /**
     * Find the enchantment map for this [ItemStack] and return it as a [MutableMap]
     */
    fun ItemStack.findEnchantments(): MutableMap<CAEnchantment, Int> = CAEnchantment.getEnchants(this)

    /**
     * Apply an [enchantments] map to this [ItemStack]
     */
    fun ItemStack.setEnchantmentsUnsafe(enchantments: Map<CAEnchantment, Int>) {
        CAEnchantment.clearEnchants(this)

        enchantments.forEach { (enchantment, level) ->
            enchantment.addEnchantmentUnsafe(this, level)
        }

    }

    /**
     * Set this [ItemStack]s durability from a combination of the
     * [first] and [second] item's durability values
     * @return if the item was repaired
     */
    fun ItemStack.repairFrom(
        first: ItemStack,
        second: ItemStack
    ): Boolean {
        (itemMeta as? Damageable)?.let {
            val durability = type.maxDurability.toInt()
            val firstDamage = (first.itemMeta as? Damageable)?.damage ?: 0
            if (firstDamage == 0) return false

            val firstDurability = durability - firstDamage
            val secondDamage = (second.itemMeta as? Damageable)?.damage ?: 0
            val secondDurability = durability - secondDamage
            val combinedDurability = firstDurability + secondDurability
            val newDurability = min(combinedDurability, durability)
            it.damage = durability - newDurability
            itemMeta = it
            return true
        }
        return false
    }

    fun ItemStack.unitRepair(
        unitAmount: Int,
        percentPerUnit: Double
    ): Int {
        (itemMeta as? Damageable)?.let {
            val durability = type.maxDurability.toInt()
            val firstDamage = it.damage
            if (firstDamage == 0) return 0
            var unitCount = 0
            var damage = firstDamage
            while ((unitCount < unitAmount) && (damage > 0)) {
                unitCount++
                damage = ceil(firstDamage - durability * percentPerUnit * unitCount).toInt()
            }

            it.damage = max(damage, 0)
            itemMeta = it
            return unitCount
        }
        return 0
    }

    /**
     * Check that this [ItemStack] can merge with the [other]
     *
     * The two items should either be the same type, or, the [other] is a book
     */
    fun ItemStack.canMergeWith(
        other: ItemStack?
    ) = (other != null) && (type == other.type || (other.isEnchantedBook()))
}