refactor: reorganize folder hierarchy

1 files changed, 245 insertions, 0 deletions

diff --git a/macros/src/injectable_impl.rs b/macros/src/injectable_impl.rs
new file mode 100644
index 0000000..3000253
--- /dev/null
+++ b/macros/src/injectable_impl.rs
@@ -0,0 +1,245 @@
+use quote::{quote, ToTokens};
+use syn::parse::{Parse, ParseStream};
+use syn::{
+    parse_str, punctuated::Punctuated, token::Comma, ExprMethodCall, FnArg,
+    GenericArgument, Ident, ImplItem, ImplItemMethod, ItemImpl, Path, PathArguments,
+    Type, TypePath,
+};
+
+const DI_CONTAINER_VAR_NAME: &str = "di_container";
+
+pub struct InjectableImpl
+{
+    pub dependency_types: Vec<Type>,
+    pub self_type: Type,
+    pub original_impl: ItemImpl,
+}
+
+impl Parse for InjectableImpl
+{
+    fn parse(input: ParseStream) -> syn::Result<Self>
+    {
+        match input.parse::<ItemImpl>() {
+            Ok(impl_parsed_input) => {
+                match Self::_get_dependency_types(&impl_parsed_input) {
+                    Ok(dependency_types) => Ok(Self {
+                        dependency_types,
+                        self_type: impl_parsed_input.self_ty.as_ref().clone(),
+                        original_impl: impl_parsed_input,
+                    }),
+                    Err(error_msg) => Err(input.error(error_msg)),
+                }
+            }
+            Err(_) => Err(input.error("Expected an impl")),
+        }
+    }
+}
+
+impl InjectableImpl
+{
+    pub fn expand(&self) -> proc_macro2::TokenStream
+    {
+        let original_impl = &self.original_impl;
+        let self_type = &self.self_type;
+
+        let di_container_var: Ident = parse_str(DI_CONTAINER_VAR_NAME).unwrap();
+
+        let get_dependencies = Self::_create_get_dependencies(&self.dependency_types);
+
+        quote! {
+            #original_impl
+
+            impl syrette::interfaces::injectable::Injectable for #self_type {
+                fn resolve(
+                    #di_container_var: &syrette::DIContainer
+                ) -> error_stack::Result<
+                    syrette::ptr::InterfacePtr<Self>,
+                    syrette::errors::injectable::ResolveError>
+                {
+                    use error_stack::ResultExt;
+
+                    return Ok(syrette::ptr::InterfacePtr::new(Self::new(
+                        #(#get_dependencies
+                            .change_context(syrette::errors::injectable::ResolveError)
+                            .attach_printable(
+                                format!(
+                                    "Unable to resolve a dependency of {}",
+                                    std::any::type_name::<#self_type>()
+                                )
+                            )?
+                        ),*
+                    )));
+                }
+            }
+        }
+    }
+
+    fn _create_get_dependencies(dependency_types: &[Type]) -> Vec<ExprMethodCall>
+    {
+        dependency_types
+            .iter()
+            .filter_map(|dep_type| match dep_type {
+                Type::TraitObject(dep_type_trait) => Some(
+                    parse_str(
+                        format!(
+                            "{}.get::<{}>()",
+                            DI_CONTAINER_VAR_NAME,
+                            dep_type_trait.to_token_stream()
+                        )
+                        .as_str(),
+                    )
+                    .unwrap(),
+                ),
+                Type::Path(dep_type_path) => {
+                    let dep_type_path_str = Self::_path_to_string(&dep_type_path.path);
+
+                    let get_method_name = if dep_type_path_str.ends_with("Factory") {
+                        "get_factory"
+                    } else {
+                        "get"
+                    };
+
+                    Some(
+                        parse_str(
+                            format!(
+                                "{}.{}::<{}>()",
+                                DI_CONTAINER_VAR_NAME, get_method_name, dep_type_path_str
+                            )
+                            .as_str(),
+                        )
+                        .unwrap(),
+                    )
+                }
+                &_ => None,
+            })
+            .collect()
+    }
+
+    fn _find_method_by_name<'impl_lt>(
+        item_impl: &'impl_lt ItemImpl,
+        method_name: &'static str,
+    ) -> Option<&'impl_lt ImplItemMethod>
+    {
+        let impl_items = &item_impl.items;
+
+        impl_items
+            .iter()
+            .filter_map(|impl_item| match impl_item {
+                ImplItem::Method(method_item) => Some(method_item),
+                &_ => None,
+            })
+            .find(|method_item| method_item.sig.ident == method_name)
+    }
+
+    #[allow(clippy::match_wildcard_for_single_variants)]
+    fn get_has_fn_args_self(fn_args: &Punctuated<FnArg, Comma>) -> bool
+    {
+        fn_args.iter().any(|arg| match arg {
+            FnArg::Receiver(_) => true,
+            &_ => false,
+        })
+    }
+
+    fn _get_fn_arg_type_paths(fn_args: &Punctuated<FnArg, Comma>) -> Vec<&TypePath>
+    {
+        fn_args
+            .iter()
+            .filter_map(|arg| match arg {
+                FnArg::Typed(typed_fn_arg) => match typed_fn_arg.ty.as_ref() {
+                    Type::Path(arg_type_path) => Some(arg_type_path),
+                    Type::Reference(ref_type_path) => match ref_type_path.elem.as_ref() {
+                        Type::Path(arg_type_path) => Some(arg_type_path),
+                        &_ => None,
+                    },
+                    &_ => None,
+                },
+                FnArg::Receiver(_receiver_fn_arg) => None,
+            })
+            .collect()
+    }
+
+    fn _path_to_string(path: &Path) -> String
+    {
+        path.segments
+            .pairs()
+            .fold(String::new(), |mut acc, segment_pair| {
+                let segment_ident = &segment_pair.value().ident;
+
+                acc.push_str(segment_ident.to_string().as_str());
+
+                let opt_colon_two = segment_pair.punct();
+
+                match opt_colon_two {
+                    Some(colon_two) => {
+                        acc.push_str(colon_two.to_token_stream().to_string().as_str());
+                    }
+                    None => {}
+                }
+
+                acc
+            })
+    }
+
+    fn _is_type_path_ptr(type_path: &TypePath) -> bool
+    {
+        let arg_type_path_string = Self::_path_to_string(&type_path.path);
+
+        arg_type_path_string == "InterfacePtr"
+            || arg_type_path_string == "ptr::InterfacePtr"
+            || arg_type_path_string == "syrrete::ptr::InterfacePtr"
+            || arg_type_path_string == "FactoryPtr"
+            || arg_type_path_string == "ptr::FactoryPtr"
+            || arg_type_path_string == "syrrete::ptr::FactoryPtr"
+    }
+
+    fn _get_dependency_types(item_impl: &ItemImpl) -> Result<Vec<Type>, &'static str>
+    {
+        let new_method_impl_item = match Self::_find_method_by_name(item_impl, "new") {
+            Some(method_item) => Ok(method_item),
+            None => Err("Missing a 'new' method"),
+        }?;
+
+        let new_method_args = &new_method_impl_item.sig.inputs;
+
+        if Self::get_has_fn_args_self(new_method_args) {
+            return Err("Unexpected self argument in 'new' method");
+        }
+
+        let new_method_arg_type_paths = Self::_get_fn_arg_type_paths(new_method_args);
+
+        if new_method_arg_type_paths
+            .iter()
+            .any(|arg_type_path| !Self::_is_type_path_ptr(arg_type_path))
+        {
+            return Err("All argument types in 'new' method must ptr types");
+        }
+
+        Ok(new_method_arg_type_paths
+            .iter()
+            .filter_map(|arg_type_path| {
+                // Assume the type path has a last segment.
+                let last_path_segment = arg_type_path.path.segments.last().unwrap();
+
+                match &last_path_segment.arguments {
+                    PathArguments::AngleBracketed(angle_bracketed_generic_args) => {
+                        let generic_args = &angle_bracketed_generic_args.args;
+
+                        let opt_first_generic_arg = generic_args.first();
+
+                        // Assume a first generic argument exists because InterfacePtr and
+                        // FactoryPtr requires one
+                        let first_generic_arg = opt_first_generic_arg.as_ref().unwrap();
+
+                        match first_generic_arg {
+                            GenericArgument::Type(first_generic_arg_type) => {
+                                Some(first_generic_arg_type.clone())
+                            }
+                            &_ => None,
+                        }
+                    }
+                    &_ => None,
+                }
+            })
+            .collect())
+    }
+}