1 files changed, 92 insertions, 0 deletions
diff --git a/src/customize/ctx.rs b/src/customize/ctx.rs
new file mode 100644
index 0000000..185fc31
--- /dev/null
+++ b/src/customize/ctx.rs
@@ -0,0 +1,92 @@
+use std::fmt;
+
+use protobuf::reflect::EnumDescriptor;
+use protobuf::reflect::FieldDescriptor;
+use protobuf::reflect::FileDescriptor;
+use protobuf::reflect::MessageDescriptor;
+use protobuf::reflect::OneofDescriptor;
+
+use crate::customize::CustomizeCallback;
+use crate::Customize;
+
+#[derive(Clone)]
+pub(crate) struct CustomizeElemCtx<'a> {
+    pub(crate) for_elem: Customize,
+    pub(crate) for_children: Customize,
+    pub(crate) callback: &'a dyn CustomizeCallback,
+}
+
+impl<'a> fmt::Debug for CustomizeElemCtx<'a> {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        f.debug_struct("CustomizeElemCtx")
+            .field("for_elem", &self.for_elem)
+            .field("for_children", &self.for_children)
+            .finish_non_exhaustive()
+    }
+}
+
+impl<'a> CustomizeElemCtx<'a> {
+    pub(crate) fn child(
+        &self,
+        elem_from_rustproto: &Customize,
+        elem_descriptor: &impl DescriptorForCustomize,
+    ) -> CustomizeElemCtx<'a> {
+        let mut for_elem = self.for_children.clone();
+        for_elem.update_with(elem_from_rustproto);
+
+        let for_children = for_elem.clone();
+
+        for_elem.update_with(&elem_descriptor.customize(self.callback));
+
+        CustomizeElemCtx {
+            for_elem,
+            for_children,
+            callback: self.callback,
+        }
+    }
+}
+
+pub(crate) trait DescriptorForCustomize {
+    fn customize(&self, callback: &dyn CustomizeCallback) -> Customize;
+}
+
+impl DescriptorForCustomize for MessageDescriptor {
+    fn customize(&self, callback: &dyn CustomizeCallback) -> Customize {
+        callback.message(self)
+    }
+}
+
+impl DescriptorForCustomize for FieldDescriptor {
+    fn customize(&self, callback: &dyn CustomizeCallback) -> Customize {
+        callback.field(self)
+    }
+}
+
+impl DescriptorForCustomize for EnumDescriptor {
+    fn customize(&self, callback: &dyn CustomizeCallback) -> Customize {
+        callback.enumeration(self)
+    }
+}
+
+impl DescriptorForCustomize for OneofDescriptor {
+    fn customize(&self, callback: &dyn CustomizeCallback) -> Customize {
+        callback.oneof(self)
+    }
+}
+
+impl DescriptorForCustomize for FileDescriptor {
+    fn customize(&self, callback: &dyn CustomizeCallback) -> Customize {
+        callback.file(self)
+    }
+}
+
+pub(crate) struct SpecialFieldPseudoDescriptor<'a> {
+    pub(crate) message: &'a MessageDescriptor,
+    pub(crate) field: &'a str,
+}
+
+impl<'a> DescriptorForCustomize for SpecialFieldPseudoDescriptor<'a> {
+    fn customize(&self, callback: &dyn CustomizeCallback) -> Customize {
+        callback.special_field(self.message, self.field)
+    }
+}