move content units-related code to separate files

src/content/loading/ItemLoader.cpp

@@ -0,0 +1,73 @@
+#define VC_ENABLE_REFLECTION
+#include "ContentUnitLoader.hpp"
+
+#include "../ContentBuilder.hpp"
+#include "coders/json.hpp"
+#include "core_defs.hpp"
+#include "data/dv.hpp"
+#include "debug/Logger.hpp"
+#include "io/io.hpp"
+#include "util/stringutil.hpp"
+#include "items/ItemDef.hpp"
+
+static debug::Logger logger("item-content-loader");
+
+template<> void ContentUnitLoader<ItemDef>::loadUnit(
+    ItemDef& def, const std::string& name, const io::path& file
+) {
+    auto root = io::read_json(file);
+    def.properties = root;
+
+    if (root.has("parent")) {
+        const auto& parentName = root["parent"].asString();
+        auto parentDef = builder.get(parentName);
+        if (parentDef == nullptr) {
+            throw std::runtime_error(
+                "Failed to find parent(" + parentName + ") for " + name
+            );
+        }
+        parentDef->cloneTo(def);
+    }
+    root.at("caption").get(def.caption);
+
+    std::string iconTypeStr = "";
+    root.at("icon-type").get(iconTypeStr);
+    if (iconTypeStr == "none") {
+        def.iconType = ItemIconType::NONE;
+    } else if (iconTypeStr == "block") {
+        def.iconType = ItemIconType::BLOCK;
+    } else if (iconTypeStr == "sprite") {
+        def.iconType = ItemIconType::SPRITE;
+    } else if (iconTypeStr.length()) {
+        logger.error() << name << ": unknown icon type - " << iconTypeStr;
+    }
+    root.at("icon").get(def.icon);
+    root.at("placing-block").get(def.placingBlock);
+    root.at("script-name").get(def.scriptName);
+    root.at("model-name").get(def.modelName);
+    root.at("stack-size").get(def.stackSize);
+    root.at("uses").get(def.uses);
+
+    std::string usesDisplayStr = "";
+    root.at("uses-display").get(usesDisplayStr);
+    if (usesDisplayStr == "none") {
+        def.usesDisplay = ItemUsesDisplay::NONE;
+    } else if (usesDisplayStr == "number") {
+        def.usesDisplay = ItemUsesDisplay::NUMBER;
+    } else if (usesDisplayStr == "relation") {
+        def.usesDisplay = ItemUsesDisplay::RELATION;
+    } else if (usesDisplayStr == "vbar") {
+        def.usesDisplay = ItemUsesDisplay::VBAR;
+    } else if (usesDisplayStr.length()) {
+        logger.error() << name << ": unknown uses display mode - " << usesDisplayStr;
+    }
+
+    if (auto found = root.at("emission")) {
+        const auto& emissionarr = *found;
+        def.emission[0] = emissionarr[0].asNumber();
+        def.emission[1] = emissionarr[1].asNumber();
+        def.emission[2] = emissionarr[2].asNumber();
+    }
+
+    def.scriptFile = pack.id + ":scripts/" + def.scriptName + ".lua";
+}