0.1.0-0-pre.9

crates/common/game-assets-lib/src/resolver.rs

@@ -0,0 +1,45 @@
+// file: crates/common/game-assets-lib/src/resolver.rs
+// version: 1
+
+/// Resolves logical asset URIs against separate common and game roots.
+#[derive(Clone, Debug, Eq, PartialEq)]
+pub struct AssetResolver {
+    common_root: std::path::PathBuf,
+    game_root: std::path::PathBuf,
+}
+
+impl AssetResolver {
+    /// Creates a resolver from physical common and game asset roots.
+    #[must_use]
+    pub fn new(common_root: impl Into<std::path::PathBuf>, game_root: impl Into<std::path::PathBuf>) -> Self {
+        return Self { common_root: common_root.into(), game_root: game_root.into() };
+    }
+
+    /// Resolves `common://` or `game://` URI into a physical path without touching the filesystem.
+    pub fn resolve(&self, uri: &str) -> Result<std::path::PathBuf, crate::AssetError> {
+        let (root, relative) = if let Some(relative) = uri.strip_prefix("common://") {
+            (&self.common_root, relative)
+        } else if let Some(relative) = uri.strip_prefix("game://") {
+            (&self.game_root, relative)
+        } else {
+            return Err(crate::AssetError::UnsupportedScheme);
+        };
+        if relative.is_empty() {
+            return Err(crate::AssetError::EmptyPath);
+        }
+        let relative_path = std::path::Path::new(relative);
+        if relative_path.is_absolute() || relative.contains('\\') {
+            return Err(crate::AssetError::InvalidPath);
+        }
+        for component in relative_path.components() {
+            if !matches!(component, std::path::Component::Normal(_)) {
+                return Err(crate::AssetError::InvalidPath);
+            }
+        }
+        return Ok(root.join(relative_path));
+    }
+}
+
+#[cfg(test)]
+#[path = "../unit_tests/resolver.rs"]
+mod tests;