1 files changed, 77 insertions, 0 deletions
diff --git a/bzipper_macros/src/impls/serialise_struct.rs b/bzipper_macros/src/impls/serialise_struct.rs
new file mode 100644
index 0000000..308a6bb
--- /dev/null
+++ b/bzipper_macros/src/impls/serialise_struct.rs
@@ -0,0 +1,77 @@
+// Copyright 2024 Gabriel Bjørnager Jensen.
+//
+// This file is part of bzipper.
+//
+// bzipper is free software: you can redistribute
+// it and/or modify it under the terms of the GNU
+// Lesser General Public License as published by
+// the Free Software Foundation, either version 3
+// of the License, or (at your option) any later
+// version.
+//
+// bzipper is distributed in the hope that it will
+// be useful, but WITHOUT ANY WARRANTY; without
+// even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+// Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Less-
+// er General Public License along with bzipper. If
+// not, see <https://www.gnu.org/licenses/>.
+
+use proc_macro2::{Span, TokenStream};
+use quote::{quote, ToTokens};
+use syn::{
+	DataStruct,
+	Fields,
+	Index,
+	Token,
+	punctuated::Punctuated
+};
+
+#[must_use]
+pub fn serialise_struct(data: &DataStruct) -> TokenStream {
+	if matches!(data.fields, Fields::Unit) {
+		quote! {
+			const SERIALISED_SIZE: usize = 0x0;
+
+			#[inline(always)]
+			fn serialise(&self, buf: &mut [u8]) -> ::bzipper::Result<()> {
+				::core::debug_assert_eq!(buf.len(), Self::SERIALISED_SIZE);
+
+				Ok(())
+			}
+		}
+	} else {
+		let mut serialised_size = Punctuated::<TokenStream, Token![+]>::new();
+		let mut chain_commands  = Punctuated::<TokenStream, Token![;]>::new();
+
+		for (index, field) in data.fields.iter().enumerate() {
+			let ty = &field.ty;
+
+			let name = field.ident
+				.as_ref()
+				.map_or_else(|| Index::from(index).to_token_stream(), ToTokens::to_token_stream);
+
+			serialised_size.push(quote! { <#ty as ::bzipper::Serialise>::SERIALISED_SIZE });
+
+			chain_commands.push(quote! { stream.append(&self.#name)? });
+		}
+
+		chain_commands.push_punct(Token![;](Span::call_site()));
+
+		quote! {
+			const SERIALISED_SIZE: usize = #serialised_size;
+
+			fn serialise(&self, buf: &mut [u8]) -> ::bzipper::Result<()> {
+				::core::debug_assert_eq!(buf.len(), Self::SERIALISED_SIZE);
+
+				let mut stream = ::bzipper::Sstream::new(buf);
+
+				#chain_commands
+
+				Ok(())
+			}
+		}
+	}
+}