1 files changed, 22 insertions, 0 deletions
diff --git a/src/plan.rs b/src/plan.rs
index 3d28d96..f3e58fa 100644
--- a/src/plan.rs
+++ b/src/plan.rs
@@ -1,5 +1,8 @@
+use std::path::Path;
+
 use anyhow::Result;
 
+use crate::package_installer::{AptConfig, PackageRequest};
 use crate::{ImageSpec, Stage};
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -24,4 +27,23 @@ impl BuildPlan {
     pub fn dependencies(&self, stage: Stage) -> &'static [Stage] {
         stage.dependencies()
     }
+
+    /// Compile package-installation inputs from the validated immutable spec.
+    /// This keeps ALT's external resolver behind the typed adapter boundary.
+    pub fn package_request(
+        &self,
+        workdir: impl AsRef<Path>,
+        apt_config: impl AsRef<Path>,
+    ) -> Result<PackageRequest> {
+        PackageRequest::new(
+            workdir,
+            AptConfig::new(apt_config)?,
+            self.spec.packages.base.iter().cloned(),
+            self.spec
+                .packages
+                .selectors
+                .iter()
+                .map(|selector| selector.as_str().to_owned()),
+        )
+    }
 }