enchantement_calculations.java

TradeOffers.SellEnchantedToolFactory toolFactory;
try {
    toolFactory = (TradeOffers.SellEnchantedToolFactory) tradeFactory;
} catch(ClassCastException e) {
    LOGGER.error("Enchanted ToolItem or ArmorItem does not have a SellEnchantedToolFactory! ");
    return 0;
}

int lvl = MAX_TOOL_ENCHANT_LVL;

int i = enchantedItem.getEnchantability();
if (i <= 0) return 0;
lvl += 1 + 2 * (i / 4 + 1);
float f = 0.15F;
lvl = Math.max(1, Math.round((float) lvl + (float) lvl * f));
int numPossibleEnchants =  intLog(lvl, 2);

List<EnchantmentLevelEntry> possibleEntriesList = EnchantmentHelper.getPossibleEntries(lvl, enchantedStack, false);
Set<EnchantmentLevelEntry> possibleEntriesSet = new HashSet<>(possibleEntriesList);
if (lvl > MAX_TOOL_ENCHANT_LVL) {
    return 0;
}

for (Map.Entry<Enchantment, Integer> entry : enchantments) {
    Enchantment enchantment = entry.getKey();
    int actualLevel = entry.getValue();

    if (enchantment.isTreasure())
        return 0;

    if (!possibleEntriesSet.contains(new EnchantmentLevelEntry(entry.getKey(), entry.getValue())))
        return 0;

    return 0;
}

int price = Math.min(toolFactory.basePrice + INDETERMINATE, 64);