Content packs structure update

src/content/ContentPack.cpp

@@ -1 +1,46 @@
 #include "ContentPack.h"
+
+#include <stdexcept>
+
+#include "../files/files.h"
+#include "../coders/json.h"
+
+namespace fs = std::filesystem;
+
+const std::string ContentPack::PACKAGE_FILENAME = "package.json";
+const std::string ContentPack::CONTENT_FILENAME = "content.json";
+
+std::filesystem::path ContentPack::getContentFile() const {
+    return folder/fs::path(CONTENT_FILENAME);
+}
+
+bool ContentPack::is_pack(std::filesystem::path folder) {
+    return fs::is_regular_file(folder/fs::path(PACKAGE_FILENAME));
+}
+
+ContentPack ContentPack::read(std::filesystem::path folder) {
+    auto root = files::read_json(folder/fs::path(PACKAGE_FILENAME));
+    ContentPack pack;
+    root->str("id", pack.id);
+    root->str("title", pack.title);
+    root->str("version", pack.version);
+    pack.folder = folder;
+    if (pack.id == "none")
+        throw std::runtime_error("content-pack id is none: "+folder.u8string());
+    return pack;
+}
+
+void ContentPack::scan(fs::path rootfolder,
+                       std::vector<ContentPack>& packs) {
+    if (!fs::is_directory(rootfolder)) {
+        return;
+    }
+    for (auto entry : fs::directory_iterator(rootfolder)) {
+        fs::path folder = entry.path();
+        if (!fs::is_directory(folder))
+            continue;
+        if (!is_pack(folder))
+            continue;
+        packs.push_back(read(folder));
+    }
+}