use std::time::{Instant, SystemTime, UNIX_EPOCH};
use tree_sitter::{Node as TsNode, Parser, Tree};
use crate::extraction::complexity::{count_complexity, R_COMPLEXITY};
use crate::types::{
generate_node_id, Edge, EdgeKind, ExtractionResult, Node, NodeKind, UnresolvedRef, Visibility,
};
pub struct RExtractor;
struct ExtractionState {
nodes: Vec<Node>,
edges: Vec<Edge>,
unresolved_refs: Vec<UnresolvedRef>,
errors: Vec<String>,
node_stack: Vec<(String, String)>,
file_path: String,
source: Vec<u8>,
timestamp: u64,
}
impl ExtractionState {
fn new(file_path: &str, source: &str) -> Self {
let timestamp = SystemTime::now()
.duration_since(UNIX_EPOCH)
.unwrap_or_default()
.as_secs();
Self {
nodes: Vec::new(),
edges: Vec::new(),
unresolved_refs: Vec::new(),
errors: Vec::new(),
node_stack: Vec::new(),
file_path: file_path.to_string(),
source: source.as_bytes().to_vec(),
timestamp,
}
}
fn qualified_prefix(&self) -> String {
let mut parts = vec![self.file_path.clone()];
for (name, _) in &self.node_stack {
parts.push(name.clone());
}
parts.join("::")
}
fn parent_node_id(&self) -> Option<&str> {
self.node_stack.last().map(|(_, id)| id.as_str())
}
fn node_text(&self, node: TsNode<'_>) -> String {
node.utf8_text(&self.source)
.unwrap_or("<invalid utf8>")
.to_string()
}
}
impl RExtractor {
pub fn extract_r(file_path: &str, source: &str) -> ExtractionResult {
let start = Instant::now();
let mut state = ExtractionState::new(file_path, source);
let tree = match Self::parse_source(source) {
Ok(t) => t,
Err(msg) => {
state.errors.push(msg);
return Self::build_result(state, start);
}
};
let file_node = Node {
id: generate_node_id(file_path, &NodeKind::File, file_path, 0),
kind: NodeKind::File,
name: file_path.to_string(),
qualified_name: file_path.to_string(),
file_path: file_path.to_string(),
start_line: 0,
end_line: source.lines().count().saturating_sub(1) as u32,
start_column: 0,
end_column: 0,
signature: None,
docstring: None,
visibility: Visibility::Pub,
is_async: false,
branches: 0,
loops: 0,
returns: 0,
max_nesting: 0,
unsafe_blocks: 0,
unchecked_calls: 0,
assertions: 0,
updated_at: state.timestamp,
};
let file_node_id = file_node.id.clone();
state.nodes.push(file_node);
state.node_stack.push((file_path.to_string(), file_node_id));
let root = tree.root_node();
Self::visit_children(&mut state, root);
state.node_stack.pop();
Self::build_result(state, start)
}
fn parse_source(source: &str) -> Result<Tree, String> {
let mut parser = Parser::new();
let language = crate::extraction::ts_provider::language("r");
parser
.set_language(&language)
.map_err(|e| format!("failed to load R grammar: {e}"))?;
parser
.parse(source, None)
.ok_or_else(|| "tree-sitter parse returned None".to_string())
}
fn visit_children(state: &mut ExtractionState, node: TsNode<'_>) {
let mut cursor = node.walk();
if cursor.goto_first_child() {
loop {
Self::visit_node(state, cursor.node());
if !cursor.goto_next_sibling() {
break;
}
}
}
}
fn visit_node(state: &mut ExtractionState, node: TsNode<'_>) {
match node.kind() {
"binary_operator" => Self::visit_assignment(state, node),
_ => Self::visit_children(state, node),
}
}
fn visit_assignment(state: &mut ExtractionState, node: TsNode<'_>) {
let (Some(lhs), Some(op_node), Some(rhs)) = (node.child(0), node.child(1), node.child(2))
else {
return;
};
let op = state.node_text(op_node);
if op != "<-" && op != "=" && op != "<<-" {
Self::visit_children(state, node);
return;
}
if rhs.kind() != "function_definition" {
Self::visit_node(state, rhs);
return;
}
let name = match lhs.kind() {
"identifier" => state.node_text(lhs),
"namespace_operator" => {
lhs.child((lhs.child_count() - 1) as u32)
.map(|n| state.node_text(n))
.unwrap_or_else(|| state.node_text(lhs))
}
_ => state.node_text(lhs),
};
let docstring = Self::extract_docstring(state, node);
let signature = Self::extract_signature(state, rhs);
let start_line = node.start_position().row as u32;
let end_line = node.end_position().row as u32;
let qualified_name = format!("{}::{}", state.qualified_prefix(), name);
let id = generate_node_id(&state.file_path, &NodeKind::Function, &name, start_line);
let metrics = if rhs.child_count() > 0 {
count_complexity(rhs, &R_COMPLEXITY, &state.source)
} else {
Default::default()
};
let graph_node = Node {
id: id.clone(),
kind: NodeKind::Function,
name: name.clone(),
qualified_name,
file_path: state.file_path.clone(),
start_line,
end_line,
start_column: node.start_position().column as u32,
end_column: node.end_position().column as u32,
signature,
docstring,
visibility: Visibility::Pub,
is_async: false,
branches: metrics.branches,
loops: metrics.loops,
returns: metrics.returns,
max_nesting: metrics.max_nesting,
unsafe_blocks: 0,
unchecked_calls: metrics.unchecked_calls,
assertions: metrics.assertions,
updated_at: state.timestamp,
};
state.nodes.push(graph_node);
if let Some(parent_id) = state.parent_node_id() {
state.edges.push(Edge {
source: parent_id.to_string(),
target: id.clone(),
kind: EdgeKind::Contains,
line: Some(start_line),
});
}
if let Some(body) = rhs.child_by_field_name("body") {
Self::extract_calls(state, body, &id);
}
}
fn extract_calls(state: &mut ExtractionState, node: TsNode<'_>, fn_id: &str) {
let mut cursor = node.walk();
if cursor.goto_first_child() {
loop {
let child = cursor.node();
if child.kind() == "call" {
if let Some(callee) = child.child(0) {
let name = state.node_text(callee);
state.unresolved_refs.push(UnresolvedRef {
from_node_id: fn_id.to_string(),
reference_name: name,
reference_kind: EdgeKind::Calls,
line: child.start_position().row as u32,
column: child.start_position().column as u32,
file_path: state.file_path.clone(),
});
}
Self::extract_calls(state, child, fn_id);
} else if child.kind() != "function_definition" {
Self::extract_calls(state, child, fn_id);
}
if !cursor.goto_next_sibling() {
break;
}
}
}
}
fn extract_signature(state: &ExtractionState, fn_def: TsNode<'_>) -> Option<String> {
if let Some(params) = fn_def.child_by_field_name("parameters") {
return Some(format!("function{}", state.node_text(params)));
}
let text = state.node_text(fn_def);
text.lines().next().map(|l| l.trim().to_string())
}
fn extract_docstring(state: &ExtractionState, node: TsNode<'_>) -> Option<String> {
let mut comments = Vec::new();
let mut prev = node.prev_named_sibling();
while let Some(p) = prev {
if p.kind() == "comment" {
let text = state.node_text(p);
if text.starts_with("#'") {
comments.push(text.trim_start_matches("#'").trim().to_string());
prev = p.prev_named_sibling();
} else {
break;
}
} else {
break;
}
}
if comments.is_empty() {
return None;
}
comments.reverse();
Some(comments.join("\n"))
}
fn build_result(state: ExtractionState, start: Instant) -> ExtractionResult {
ExtractionResult {
nodes: state.nodes,
edges: state.edges,
unresolved_refs: state.unresolved_refs,
errors: state.errors,
duration_ms: start.elapsed().as_millis() as u64,
}
}
}
impl crate::extraction::LanguageExtractor for RExtractor {
fn extensions(&self) -> &[&str] {
&["r", "R"]
}
fn language_name(&self) -> &'static str {
"R"
}
fn extract(&self, file_path: &str, source: &str) -> ExtractionResult {
Self::extract_r(file_path, source)
}
}