1 files changed, 97 insertions, 0 deletions
diff --git a/src/nix/installables.hh b/src/nix/installables.hh
new file mode 100644
index 000000000..020a61a2b
--- /dev/null
+++ b/src/nix/installables.hh
@@ -0,0 +1,97 @@
+#pragma once
+
+#include "util.hh"
+#include "flake/eval-cache.hh"
+
+#include <optional>
+
+namespace nix {
+
+struct Value;
+class EvalState;
+class SourceExprCommand;
+
+struct Buildable
+{
+    Path drvPath; // may be empty
+    std::map<std::string, Path> outputs;
+};
+
+typedef std::vector<Buildable> Buildables;
+
+struct App
+{
+    PathSet context;
+    Path program;
+    // FIXME: add args, sandbox settings, metadata, ...
+
+    App(EvalState & state, Value & vApp);
+};
+
+struct Installable
+{
+    virtual ~Installable() { }
+
+    virtual std::string what() = 0;
+
+    virtual Buildables toBuildables()
+    {
+        throw Error("argument '%s' cannot be built", what());
+    }
+
+    Buildable toBuildable();
+
+    App toApp(EvalState & state);
+
+    virtual Value * toValue(EvalState & state)
+    {
+        throw Error("argument '%s' cannot be evaluated", what());
+    }
+
+    /* Return a value only if this installable is a store path or a
+       symlink to it. */
+    virtual std::optional<Path> getStorePath()
+    {
+        return {};
+    }
+};
+
+struct InstallableValue : Installable
+{
+    SourceExprCommand & cmd;
+
+    InstallableValue(SourceExprCommand & cmd) : cmd(cmd) { }
+
+    virtual std::vector<flake::EvalCache::Derivation> toDerivations();
+
+    Buildables toBuildables() override;
+};
+
+struct InstallableFlake : InstallableValue
+{
+    FlakeRef flakeRef;
+    Strings attrPaths;
+    Strings prefixes;
+
+    InstallableFlake(SourceExprCommand & cmd, FlakeRef && flakeRef, Strings attrPaths)
+        : InstallableValue(cmd), flakeRef(flakeRef), attrPaths(std::move(attrPaths))
+    { }
+
+    InstallableFlake(SourceExprCommand & cmd, FlakeRef && flakeRef,
+        std::string attrPath, Strings && prefixes)
+        : InstallableValue(cmd), flakeRef(flakeRef), attrPaths{attrPath},
+          prefixes(prefixes)
+    { }
+
+    std::string what() override { return flakeRef.to_string() + ":" + *attrPaths.begin(); }
+
+    std::vector<std::string> getActualAttrPaths();
+
+    Value * getFlakeOutputs(EvalState & state, const flake::ResolvedFlake & resFlake);
+
+    std::vector<flake::EvalCache::Derivation> toDerivations() override;
+
+    Value * toValue(EvalState & state) override;
+};
+
+}