ATLYSS TechPendium

const VENDOR_SELL_MODIFIER = 0.38;


const Utils = require("Utils");

function getSellPrice(buyPrice) {
    return buyPrice ? Math.floor(Math.max(buyPrice * VENDOR_SELL_MODIFIER, 1)) : "N/A";
}

async function calculateItemDropFromList(dropList, itemGuid, options = {}) {
    if (!Array.isArray(dropList) || !itemGuid) {
        return null;
    }

    const entry = dropList.find(e => e?.guid === itemGuid);
    if (!entry) return null;

    const dropChance = Number(entry.dropChance) || 0;

    // 🔹 Creep-style quantity (Unity Random.Range)
    if (entry.dropQuantity !== undefined) {
        const dropQuantity = Number(entry.dropQuantity) || 1;

        // Unity Random.Range(1, dropQuantity)
        const maxActual = Math.max(1, dropQuantity - 1);
        const averageQuantity =
            maxActual > 1 ? (1 + maxActual) / 2 : 1;

        return {
            dropChance,
            quantityMin: 1,
            quantityMax: maxActual,
            averageQuantity,
            effectiveDrop: dropChance * averageQuantity
        };
    }

    // 🔹 Loot-table fixed quantity
    const quantity = Number(entry.quantity) || 1;

    return {
        dropChance,
        quantityMin: quantity,
        quantityMax: quantity,
        averageQuantity: quantity,
        effectiveDrop: dropChance * quantity
    };
}

async function calculateCreepDrops(creep, itemGuid, options = {}) {
    if (
        !creep ||
        !itemGuid ||
        !creep.loot ||
        !Array.isArray(creep.loot.items)
    ) {
        return null;
    }

    const lootEntry = creep.loot.items.find(
        entry => entry?.guid === itemGuid
    );

    if (!lootEntry) return null;

    const item = await Utils.resolveItemByGuid(itemGuid, options);
    if (!item) return null;

    const dropChance = Number(lootEntry.dropChance) || 0;

    const dropQuantity = Number(lootEntry.dropQuantity) || 1;

    // Unity Random.Range(1, dropQuantity)
    const maxActual = Math.max(1, dropQuantity - 1);
    const averageQuantity = maxActual > 1
        ? (1 + maxActual) / 2
        : 1;

    return {
        creepId: creep.id ?? null,
        creepName: creep.name ?? null,
        itemGuid,
        itemName: item.name ?? lootEntry.name ?? null,
        dropChance,
        quantityMin: 1,
        quantityMax: maxActual,
        averageQuantity,
        effectiveDrop: dropChance * averageQuantity
    };
}

async function calculateCreepDrops(creep, itemGuid, options = {}) {
    if (!creep?.loot?.items) return null;

    return calculateItemDropFromList(
        creep.loot.items,
        itemGuid,
        options
    );
}

async function calculateLootTableDrops(table, itemGuid, options = {}) {
    if (!table?.drops) return null;

    return calculateItemDropFromList(
        table.drops,
        itemGuid,
        options
    );
}

exports = {
  getSellPrice,
  calculateCreepDrops,
  calculateLootTableDrops
}