Add quirk for stone_slab rename

The old stone_slab block from pre-1.14 has been renamed to
smooth_stone_slab, and the name stone_slab was reused for a new block.
Resolve the palette entry depending on the chunk's dataVersion.

src/Resource/LegacyBlockType.inc

@@ -143,7 +143,7 @@
 /*  41 */ simple("gold_block"),
 /*  42 */ simple("iron_block"),
 /*  43 */ {
-	"stone_slab",
+	"smooth_stone_slab",
 	"sandstone_slab",
 	"oak_slab",
 	"cobblestone_slab",
@@ -153,7 +153,7 @@
 	"quartz_slab",
 },
 /*  44 */ {
-	"stone_slab",
+	"smooth_stone_slab",
 	"sandstone_slab",
 	"oak_slab",
 	"cobblestone_slab",

src/World/Chunk.cpp

@@ -25,6 +25,7 @@
 
 
 #include "Chunk.hpp"
+#include "../NBT/IntTag.hpp"
 #include "../NBT/ListTag.hpp"
 #include "../NBT/StringTag.hpp"
 
@@ -51,9 +52,12 @@ Chunk::Chunk(const ChunkData *data) {
 	else if (biomeInts && biomeInts->getLength() != SIZE*SIZE)
 		throw std::invalid_argument("corrupt biome data");
 
+	auto dataVersionTag = data->getRoot().get<NBT::IntTag>("DataVersion");
+	uint32_t dataVersion = dataVersionTag ? dataVersionTag->getValue() : 0;
+
 	for (auto &sTag : *sectionsTag) {
 		auto s = std::dynamic_pointer_cast<const NBT::CompoundTag>(sTag);
-		std::unique_ptr<Section> section = Section::makeSection(s);
+		std::unique_ptr<Section> section = Section::makeSection(s, dataVersion);
 		size_t Y = section->getY();
 		sections.resize(Y);
 		sections.push_back(std::move(section));

src/World/Section.cpp

@@ -44,12 +44,12 @@ const Resource::BlockType * Section::getBlockStateAt(size_t, size_t, size_t) con
 	return nullptr;
 }
 
-std::unique_ptr<Section> Section::makeSection(const std::shared_ptr<const NBT::CompoundTag> &section) {
+std::unique_ptr<Section> Section::makeSection(const std::shared_ptr<const NBT::CompoundTag> &section, uint32_t dataVersion) {
 	std::shared_ptr<const NBT::LongArrayTag> blockStates = section->get<NBT::LongArrayTag>("BlockStates");
 	if (blockStates) {
 		const std::shared_ptr<const NBT::ListTag> palette = assertValue(section->get<NBT::ListTag>("Palette"));
 
-		return std::unique_ptr<Section>(new PaletteSection(section, std::move(blockStates), palette));
+		return std::unique_ptr<Section>(new PaletteSection(section, std::move(blockStates), palette, dataVersion));
 	}
 
 	std::shared_ptr<const NBT::ByteArrayTag> blocks = section->get<NBT::ByteArrayTag>("Blocks");
@@ -71,10 +71,18 @@ const Resource::BlockType * LegacySection::getBlockStateAt(size_t x, size_t y, s
 }
 
 
+const Resource::BlockType * PaletteSection::lookup(const std::string &name, uint32_t dataVersion) {
+	if (dataVersion < 1900 && name == "minecraft:stone_slab")
+		return Resource::BlockType::lookup("minecraft:smooth_stone_slab");
+
+	return Resource::BlockType::lookup(name);
+}
+
 PaletteSection::PaletteSection(
 	const std::shared_ptr<const NBT::CompoundTag> &section,
 	std::shared_ptr<const NBT::LongArrayTag> &&blockStates0,
-	const std::shared_ptr<const NBT::ListTag> &paletteData
+	const std::shared_ptr<const NBT::ListTag> &paletteData,
+	uint32_t dataVersion
 ) : Section(section), blockStates(blockStates0) {
 	if (blockStates->getLength() % 64)
 		throw std::invalid_argument("corrupt section data");
@@ -90,7 +98,7 @@ PaletteSection::PaletteSection(
 		const NBT::CompoundTag &paletteEntry = *assertValue(dynamic_cast<const NBT::CompoundTag *>(entry.get()));
 		std::string name = assertValue(paletteEntry.get<NBT::StringTag>("Name"))->getValue();
 
-		const Resource::BlockType *type = Resource::BlockType::lookup(name);
+		const Resource::BlockType *type = lookup(name, dataVersion);
 		if (!type)
 			std::fprintf(stderr, "Warning: unknown block type: %s\n", name.c_str());
 

src/World/Section.hpp

@@ -81,7 +81,7 @@ public:
 		return getHalf(blockLight->getValue(), x, y, z);
 	}
 
-	static std::unique_ptr<Section> makeSection(const std::shared_ptr<const NBT::CompoundTag> &section);
+	static std::unique_ptr<Section> makeSection(const std::shared_ptr<const NBT::CompoundTag> &section, uint32_t dataVersion);
 };
 
 class LegacySection : public Section {
@@ -116,6 +116,8 @@ private:
 	uint16_t mask;
 
 
+	static const Resource::BlockType * lookup(const std::string &name, uint32_t dataVersion);
+
 	static size_t mangleByteIndex(size_t index) {
 		return (index & ~(size_t)7) + 7 - (index & 7);
 	}
@@ -124,7 +126,8 @@ public:
 	PaletteSection(
 		const std::shared_ptr<const NBT::CompoundTag> &section,
 		std::shared_ptr<const NBT::LongArrayTag> &&blockStates0,
-		const std::shared_ptr<const NBT::ListTag> &paletteData
+		const std::shared_ptr<const NBT::ListTag> &paletteData,
+		uint32_t dataVersion
 	);
 
 	virtual const Resource::BlockType * getBlockStateAt(size_t x, size_t y, size_t z) const;