feat: add lootContextFor and smeltedForm to Loot

core/src/Loot.cpp

@@ -314,3 +314,114 @@ int LootRoll::totalCount() const {
     return total;
 }
 
+LootContext lootContextFor(const HurtSource& source, ItemId tool, const EnchantSet& toolEnchants,
+                           uint32_t seed) {
+    LootContext context;
+    context.seed = seed != 0 ? seed : 0x9e3779b9u;
+    context.killedBy = source.type;
+    context.fiery = source.fiery || isFireDamage(source.type);
+    context.playerKill = source.byPlayer;
+    context.tool = tool;
+    context.toolEnchants = toolEnchants;
+    return context;
+}
+
+ItemId smeltedForm(ItemId raw) {
+    switch (raw) {
+        case ItemId::RawPorkchop: return ItemId::CookedPorkchop;
+        case ItemId::RawBeef:     return ItemId::CookedBeef;
+        case ItemId::RawMutton:   return ItemId::CookedMutton;
+        case ItemId::IronOre:     return ItemId::IronIngot;
+        case ItemId::GoldOre:     return ItemId::GoldIngot;
+        default:                  return raw;
+    }
+}
+
+bool toolQualifiesFor(Block block, ItemId tool) {
+    if (correctToolFor(block) != ToolType::Pickaxe) return true;
+
+    const ItemInfo& info = itemInfo(tool);
+    if (info.toolType != ToolType::Pickaxe) return false;
+    switch (block) {
+        case Block::DiamondOre:
+        case Block::EmeraldOre:
+        case Block::GoldOre:
+            return info.toolTier == ToolTier::Iron || info.toolTier == ToolTier::Diamond;
+        case Block::IronOre:
+        case Block::LapisOre:
+        case Block::RedstoneOre:
+            return info.toolTier != ToolTier::Wood && info.toolTier != ToolTier::Gold;
+        default:
+            return true;
+    }
+}
+
+const LootTable& blockLootTable(Block block) {
+    static const std::vector<LootTable> tables = buildBlockTables();
+    if (block >= Block::Count) return emptyTable();
+    return tables[static_cast<std::size_t>(block)];
+}
+
+const LootTable& mobLootTable(LootTable::MobKind kind) {
+    static const std::vector<LootTable> tables = {
+        zombieTable(),
+        skeletonTable(),
+        creeperTable(),
+        meatTable(ItemId::RawMutton, 1, 2),
+        meatTable(ItemId::RawBeef, 1, 3),
+        meatTable(ItemId::RawPorkchop, 1, 3),
+    };
+    if (kind >= LootTable::MobKind::Count) return emptyTable();
+    return tables[static_cast<std::size_t>(kind)];
+}
+
+const LootTable& chestLootTable(LootTable::ChestKind kind) {
+    static const std::vector<LootTable> tables = {
+        dungeonChestTable(),
+        villageChestTable(),
+        templeChestTable(),
+    };
+    if (kind >= LootTable::ChestKind::Count) return emptyTable();
+    return tables[static_cast<std::size_t>(kind)];
+}
+
+LootRoll rollLootTable(const LootTable& table, const LootContext& context) {
+    LootRoll roll;
+    uint32_t rng = context.seed != 0 ? context.seed : 0x9e3779b9u;
+
+    for (const LootPool& pool : table.pools) {
+        int rolls = rollBetween(rng, pool.minRolls, pool.maxRolls);
+        rolls += pool.bonusRollsPerLooting * context.looting();
+        for (int r = 0; r < rolls; ++r) {
+            int totalWeight = 0;
+            for (const LootEntry& entry : pool.entries) {
+                if (conditionsPass(entry, context)) totalWeight += entry.weight;
+            }
+            if (totalWeight <= 0) continue;
+            int pick = rollBelow(rng, totalWeight);
+            for (const LootEntry& entry : pool.entries) {
+                if (!conditionsPass(entry, context)) continue;
+                pick -= entry.weight;
+                if (pick >= 0) continue;
+                emitEntry(roll, entry, context, rng);
+                break;
+            }
+        }
+    }
+    return roll;
+}
+
+LootRoll rollBlockDrops(Block block, const LootContext& context) {
+    if (!toolQualifiesFor(block, context.tool)) return {};
+    return rollLootTable(blockLootTable(block), context);
+}
+
+LootRoll rollMobDrops(LootTable::MobKind kind, const LootContext& context) {
+    return rollLootTable(mobLootTable(kind), context);
+}
+
+LootRoll rollChestContents(LootTable::ChestKind kind, const LootContext& context) {
+    return rollLootTable(chestLootTable(kind), context);
+}
+
+} // namespace vf