From 1253129403955045976dca216f268a66e0a4d5f1 Mon Sep 17 00:00:00 2001
From: pointer-to-bios <pointer-to-bios@outlook.com>
Date: Mon, 23 Sep 2024 12:57:16 +0800
Subject: [PATCH] basic api calling interface

---
 .gitignore |   1 +
 Cargo.toml |  10 +++++
 src/lib.rs | 117 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 128 insertions(+)
 create mode 100644 .gitignore
 create mode 100644 Cargo.toml
 create mode 100644 src/lib.rs

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..ea8c4bf
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+/target
diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..e7cf6d0
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,10 @@
+[package]
+name = "nonx-api"
+version = "0.1.0"
+edition = "2021"
+
+[lib]
+proc-macro = true
+
+[dependencies]
+nonx = { path = "../nonx" }
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..138adc5
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,117 @@
+extern crate alloc;
+
+use alloc::{string::ToString, vec::Vec};
+use proc_macro::{token_stream::IntoIter, Delimiter, Group, TokenStream, TokenTree};
+
+fn insert_stream_at(ident: &str, stream: TokenStream, rhs: TokenStream) -> TokenStream {
+    let mut res = TokenStream::new();
+    for tree in stream.into_iter() {
+        if let TokenTree::Ident(i) = &tree {
+            if i.to_string() == ident {
+                res.extend(rhs.clone());
+            } else {
+                res.extend([TokenTree::Ident(i.clone())]);
+            }
+        } else if let TokenTree::Group(g) = &tree {
+            res.extend([TokenTree::Group(Group::new(
+                g.delimiter(),
+                insert_stream_at(ident, g.stream(), rhs.clone()),
+            ))]);
+        } else {
+            res.extend([tree]);
+        }
+    }
+    res
+}
+
+#[proc_macro]
+pub fn nonx_api(input: TokenStream) -> TokenStream {
+    if !nonx::utils::api_map_inited() {
+        nonx::utils::api_remap();
+    }
+    let medium = "{
+        use crate::plugin::api_bus::APIBus;
+        (*((*APIBus::get()).api(__api_name) as *mut fn(__api_arguments) -> __api_return))(__args)
+    }"
+    .parse::<TokenStream>()
+    .unwrap();
+    let mut input_iter = input.into_iter();
+    let api_name = gen_api_name(&mut input_iter);
+    let api_path = gen_api_path(&api_name);
+    let api_name_str_tokenstream = gen_api_name_str_tokenstream(&api_name);
+    let args = gen_args(&mut input_iter);
+    let medium = insert_stream_at("__api_name", medium, api_name_str_tokenstream);
+    let medium = insert_stream_at(
+        "__api_arguments",
+        medium,
+        nonx::utils::api_map_get(&api_path).args.parse().unwrap(),
+    );
+    let medium = insert_stream_at(
+        "__api_return",
+        medium,
+        nonx::utils::api_map_get(&api_path).rets.parse().unwrap(),
+    );
+    let medium = insert_stream_at("__args", medium, args);
+    medium
+}
+
+fn gen_args(input_iter: &mut IntoIter) -> TokenStream {
+    let mut res = TokenStream::new();
+    while let Some(ref t) = input_iter.next() {
+        res.extend([t.clone()]);
+    }
+    res
+}
+
+fn gen_api_name_str_tokenstream(api_name: &TokenStream) -> TokenStream {
+    let mut res = "stringify!".parse::<TokenStream>().unwrap();
+    res.extend([TokenTree::Group(Group::new(
+        Delimiter::Parenthesis,
+        api_name.clone(),
+    ))]);
+    res
+}
+
+fn gen_api_name(input_iter: &mut IntoIter) -> TokenStream {
+    let mut res = TokenStream::new();
+    while let Some(ref t) = input_iter.next() {
+        if let TokenTree::Punct(p) = t {
+            if p.as_char() == ',' {
+                break;
+            }
+        }
+        res.extend([t.clone()]);
+    }
+    res
+}
+
+fn gen_api_path(api_name: &TokenStream) -> Vec<String> {
+    let mut res = Vec::new();
+    let mut single = false;
+    for t in api_name.clone() {
+        match t {
+            TokenTree::Group(_) => panic!("Unexpected token, api path expected."),
+            TokenTree::Ident(i) => {
+                if single {
+                    panic!("Path spliter \'::\' expected, only single \':\'.");
+                }
+                res.push(i.to_string());
+            }
+            TokenTree::Punct(p) => {
+                if p.as_char() != ':' {
+                    panic!("Unexpected token \'{}\' in api path.", p.as_char())
+                }
+                if !single {
+                    single = true;
+                } else {
+                    single = false
+                }
+            }
+            TokenTree::Literal(_) => panic!("Unexpected token, api path expected."),
+        }
+    }
+    if res.len() != 3 {
+        panic!("Api path's depth must be 3.");
+    }
+    res
+}