use proc_macro::TokenStream;
use quote::quote;
use syn::{FnArg, ItemFn, Pat, ext::IdentExt};
use crate::{
args::{self, Argument, RenameRuleExt, RenameTarget},
utils::{
GeneratorResult, gen_deprecation, generate_default, get_crate_path, get_rustdoc,
parse_graphql_attrs, remove_graphql_attrs, visible_fn,
},
};
pub fn generate(
directive_args: &args::TypeDirective,
item_fn: &mut ItemFn,
) -> GeneratorResult<TokenStream> {
let crate_name = get_crate_path(&directive_args.crate_path, directive_args.internal);
let ident = &item_fn.sig.ident;
let vis = &item_fn.vis;
let directive_name = if !directive_args.name_type {
let name = directive_args
.name
.clone()
.unwrap_or_else(|| item_fn.sig.ident.to_string());
quote!(::std::borrow::Cow::Borrowed(#name))
} else {
quote!(<Self as #crate_name::TypeName>::type_name())
};
let desc = get_rustdoc(&item_fn.attrs)?
.map(|s| quote!(::std::option::Option::Some(::std::string::ToString::to_string(#s))))
.unwrap_or_else(|| quote!(::std::option::Option::None));
let visible = visible_fn(&directive_args.visible);
let repeatable = directive_args.repeatable;
let composable = match directive_args.composable.as_ref() {
Some(url) => quote!(::std::option::Option::Some(::std::string::ToString::to_string(#url))),
None => quote!(::std::option::Option::None),
};
let mut schema_args = Vec::new();
let mut input_args = Vec::new();
let mut directive_input_args = Vec::new();
for arg in item_fn.sig.inputs.iter_mut() {
let mut arg_info = None;
if let FnArg::Typed(pat) = arg
&& let Pat::Ident(ident) = &*pat.pat
{
arg_info = Some((ident.clone(), pat.ty.clone(), pat.attrs.clone()));
remove_graphql_attrs(&mut pat.attrs);
}
let (arg_ident, arg_ty, arg_attrs) = match arg_info {
Some(info) => info,
None => {
return Err(syn::Error::new_spanned(arg, "Invalid argument type.").into());
}
};
let Argument {
name,
desc,
default,
default_with,
visible,
secret,
directives,
deprecation,
..
} = parse_graphql_attrs::<args::Argument>(&arg_attrs)?.unwrap_or_default();
let name = name.clone().unwrap_or_else(|| {
directive_args
.rename_args
.rename(arg_ident.ident.unraw().to_string(), RenameTarget::Argument)
});
let desc = desc
.as_ref()
.map(|s| quote! {::std::option::Option::Some(::std::string::ToString::to_string(#s))})
.unwrap_or_else(|| quote! {::std::option::Option::None});
let default = generate_default(&default, &default_with)?;
let schema_default = default
.as_ref()
.map(|value| {
quote! {
::std::option::Option::Some(::std::string::ToString::to_string(
&<#arg_ty as #crate_name::InputType>::to_value(&#value)
))
}
})
.unwrap_or_else(|| quote! {::std::option::Option::None});
let visible = visible_fn(&visible);
let deprecation = gen_deprecation(&deprecation, &crate_name);
schema_args.push(quote! {
args.insert(::std::borrow::ToOwned::to_owned(#name), #crate_name::registry::MetaInputValue {
name: ::std::string::ToString::to_string(#name),
description: #desc,
ty: <#arg_ty as #crate_name::InputType>::create_type_info(registry),
deprecation: #deprecation,
default_value: #schema_default,
visible: #visible,
inaccessible: false,
tags: ::std::default::Default::default(),
is_secret: #secret,
directive_invocations: ::std::vec![ #(#directives),* ],
});
});
input_args.push(quote! { #arg });
directive_input_args.push(quote! {
if let Some(val) = #crate_name::InputType::as_raw_value(&#arg_ident) {
args.insert(::std::string::ToString::to_string(#name), #crate_name::InputType::to_value(val));
};
});
}
let locations = directive_args
.locations
.iter()
.map(|loc| {
let loc = quote::format_ident!("{}", loc.to_string());
quote!(#crate_name::registry::__DirectiveLocation::#loc)
})
.collect::<Vec<_>>();
if locations.is_empty() {
return Err(syn::Error::new(
ident.span(),
"At least one location is required for the directive.",
)
.into());
}
let location_traits = directive_args
.locations
.iter()
.map(|loc| loc.location_trait_identifier())
.collect::<Vec<_>>();
let expanded = quote! {
#[allow(non_camel_case_types)]
#vis struct #ident;
impl #crate_name::TypeDirective for #ident {
fn name(&self) -> ::std::borrow::Cow<'static, ::std::primitive::str> {
#directive_name
}
fn register(&self, registry: &mut #crate_name::registry::Registry) {
let meta = #crate_name::registry::MetaDirective {
name: ::std::borrow::Cow::into_owned(#directive_name),
description: #desc,
locations: vec![#(#locations),*],
args: {
#[allow(unused_mut)]
let mut args = #crate_name::indexmap::IndexMap::new();
#(#schema_args)*
args
},
is_repeatable: #repeatable,
visible: #visible,
composable: #composable,
};
registry.add_directive(meta);
}
}
#(impl #crate_name::registry::location_traits::#location_traits for #ident {})*
impl #ident {
pub fn apply(#(#input_args),*) -> #crate_name::registry::MetaDirectiveInvocation {
let directive = ::std::borrow::Cow::into_owned(#directive_name);
let mut args = #crate_name::indexmap::IndexMap::new();
#(#directive_input_args)*;
#crate_name::registry::MetaDirectiveInvocation {
name: directive,
args,
}
}
}
};
Ok(expanded.into())
}