Changeset: 36 Add basic machinery for levels (no saving/loading yet)

1 files changed, 164 insertions, 1 deletions

diff --git a/source/Level.cpp b/source/Level.cpp
index eec7b85..ea3e9a9 100644
--- a/source/Level.cpp
+++ b/source/Level.cpp
@@ -1,12 +1,175 @@
 #include "Level.hpp"
 
+#include "AppConfig.hpp"
+#include "PodVector.hpp"
+#include "RapidJsonHelper.hpp"
+#include "ScopeGuard.hpp"
+#include "Utils.hpp"
+
+#include <rapidjson/document.h>
+#include <rapidjson/filereadstream.h>
+#include <rapidjson/filewritestream.h>
+#include <rapidjson/writer.h>
+#include <cstdio>
+#include <filesystem>
+
+using namespace std::literals;
+namespace fs = std::filesystem;
+
+constexpr auto kInvalidEntryId = std::numeric_limits<size_t>::max();
+
+struct Level::InstanciationEntry {
+	// If set to std::numeric_limits<size_t>::max(), this object is parented to the "root" provided when instanciating
+	size_t parentId;
+	rapidjson::Document data;
+};
+
+Level::Level() = default;
+
+Level::~Level() = default;
+
+void Level::Instanciate(GameObject* relRoot) const {
+}
+
+void LevelManager::DiscoverFilesDesignatedLocation() {
+	auto path = AppConfig::assetDirPath / "Levels";
+	DiscoverFiles(path);
+}
+
+void LevelManager::DiscoverFiles(const std::filesystem::path& dir) {
+	for (auto& item : fs::directory_iterator(dir)) {
+		auto& path = item.path();
+		if (!item.is_regular_file()) {
+			continue;
+		}
+		if (path.extension() != ".json") {
+			continue;
+		}
+
+		// Parse uid from filename, map key
+		Uid uid;
+		uid.ReadString(path.filename().string());
+
+		// Map value
+		LoadableObject obj;
+		obj.filePath = path;
+
+		mObjByUid.try_emplace(uid, std::move(obj));
+	}
+}
+
+Level* LevelManager::FindLevel(const Uid& uid) const {
+	auto iter = mObjByUid.find(uid);
+	if (iter != mObjByUid.end()) {
+		return iter->second.level.Get();
+	} else {
+		return nullptr;
+	}
+}
+
+#define BRUSSEL_DEF_LEVEL_NAME "New Level"
+#define BRUSSEl_DEF_LEVEL_DESC "No description."
+
+Level* LevelManager::LoadLevel(const Uid& uid) {
+	auto iter = mObjByUid.find(uid);
+	if (iter != mObjByUid.end()) {
+		auto& ldObj = iter->second;
+		if (ldObj.level != nullptr) {
+			auto file = Utils::OpenCstdioFile(ldObj.filePath, Utils::Read, false);
+			if (!file) {
+				fprintf(stderr, "Cannot open file level file %s that was discovered on game startup.", ldObj.filePath.string().c_str());
+				return nullptr;
+			}
+			DEFER { fclose(file); };
+
+			char readerBuffer[65536];
+			rapidjson::FileReadStream stream(file, readerBuffer, sizeof(readerBuffer));
+
+			rapidjson::Document root;
+			root.ParseStream(stream);
+
+			Level* level;
+			ldObj.level.Attach(level = new Level());
+
+			level->mMan = this;
+
+#if defined(BRUSSEL_DEV_ENV)
+			BRUSSEL_JSON_GET_DEFAULT(root, "Name", std::string, ldObj.name, BRUSSEL_DEF_LEVEL_NAME);
+			BRUSSEL_JSON_GET_DEFAULT(root, "Description", std::string, ldObj.description, BRUSSEl_DEF_LEVEL_DESC)
+#endif
+
+			auto rvEntries = rapidjson::GetProperty(root, rapidjson::kArrayType, "DataEntries"sv);
+			if (!rvEntries) return nullptr;
+			for (auto iter = rvEntries->Begin(); iter != rvEntries->End(); ++iter) {
+				Level::InstanciationEntry entry;
+
+				BRUSSEL_JSON_GET_DEFAULT(*iter, "ParentId", int, entry.parentId, kInvalidEntryId);
+
+				auto rvDataEntry = rapidjson::GetProperty(*iter, "Data"sv);
+				if (!rvDataEntry) return nullptr;
+				entry.data.CopyFrom(*iter, entry.data.GetAllocator());
+
+				level->mEntries.push_back(std::move(entry));
+			}
+		}
+		return ldObj.level.Get();
+	} else {
+		return nullptr;
+	}
+}
+
+void LevelManager::PrepareLevel(const Uid& uid) {
+	// TODO
+}
+
+LevelManager::LoadableObject& LevelManager::AddLevel(const Uid& uid) {
+	auto&& [iter, inserted] = mObjByUid.try_emplace(uid, LoadableObject{});
+	auto& ldObj = iter->second;
+#if defined(BRUSSEL_DEV_ENV)
+	ldObj.name = BRUSSEL_DEF_LEVEL_NAME;
+	ldObj.description = BRUSSEl_DEF_LEVEL_DESC;
+#endif
+	return ldObj;
+}
+
 LevelWrapperObject::LevelWrapperObject(GameWorld* world)
-	: GameObject(KD_LevelWrapper, world) {
+	: GameObject(KD_LevelWrapper, world) //
+{
 	mStopFreePropagation = true;
 }
 
 LevelWrapperObject::~LevelWrapperObject() {
+	// Destruction/freeing of this object is handled by our parent
 	for (auto child : GetChildren()) {
 		FreeRecursive(child);
 	}
 }
+
+void LevelWrapperObject::SetBoundLevel(Level* level) {
+	if (mLevel != level) {
+		mLevel.Attach(level);
+
+		// Cleanup old children
+		// TODO needs to Resleep()?
+		auto children = RemoveAllChildren();
+		for (auto child : children) {
+			FreeRecursive(child);
+		}
+	}
+
+	level->Instanciate(this);
+
+	PodVector<GameObject*> stack;
+	stack.push_back(this);
+
+	while (!stack.empty()) {
+		auto obj = stack.back();
+		stack.pop_back();
+
+		for (auto child : obj->GetChildren()) {
+			stack.push_back(child);
+		}
+
+		obj->Awaken();
+	}
+}