use crate::detectors::base::{Detector, DetectorConfig};
use uuid::Uuid;
use crate::graph::GraphStore;
use crate::models::{deterministic_finding_id, Finding, Severity};
use anyhow::Result;
use regex::Regex;
use std::path::PathBuf;
use std::sync::OnceLock;
static LOOP: OnceLock<Regex> = OnceLock::new();
static QUERY: OnceLock<Regex> = OnceLock::new();
fn loop_pattern() -> &'static Regex {
LOOP.get_or_init(|| Regex::new(r"(?i)(for\s+\w+\s+in|\.forEach|\.map\(|\.each)").unwrap())
}
fn query_pattern() -> &'static Regex {
QUERY.get_or_init(|| Regex::new(r"(?i)(\.get\(|\.find\(|\.filter\(|\.first\(|\.where\(|\.query\(|SELECT\s|Model\.\w+\.get|await\s+\w+\.findOne)").unwrap())
}
pub struct NPlusOneDetector {
repository_path: PathBuf,
max_findings: usize,
}
impl NPlusOneDetector {
pub fn new(repository_path: impl Into<PathBuf>) -> Self {
Self { repository_path: repository_path.into(), max_findings: 50 }
}
}
impl Detector for NPlusOneDetector {
fn name(&self) -> &'static str { "n-plus-one" }
fn description(&self) -> &'static str { "Detects N+1 query patterns" }
fn detect(&self, _graph: &GraphStore) -> Result<Vec<Finding>> {
let mut findings = vec![];
let walker = ignore::WalkBuilder::new(&self.repository_path).hidden(false).git_ignore(true).build();
for entry in walker.filter_map(|e| e.ok()) {
if findings.len() >= self.max_findings { break; }
let path = entry.path();
if !path.is_file() { continue; }
let path_str = path.to_string_lossy();
if path_str.contains("test") || path_str.contains("spec") { continue; }
let ext = path.extension().and_then(|e| e.to_str()).unwrap_or("");
if !matches!(ext, "py"|"js"|"ts"|"rb"|"java"|"go") { continue; }
if let Some(content) = crate::cache::global_cache().get_content(path) {
let mut in_loop = false;
let mut loop_line = 0;
let mut brace_depth = 0;
for (i, line) in content.lines().enumerate() {
if loop_pattern().is_match(line) {
in_loop = true;
loop_line = i + 1;
brace_depth = 0;
}
if in_loop {
brace_depth += line.matches('{').count() as i32;
brace_depth -= line.matches('}').count() as i32;
if brace_depth < 0 { in_loop = false; continue; }
if query_pattern().is_match(line) {
findings.push(Finding {
id: Uuid::new_v4().to_string(),
detector: "NPlusOneDetector".to_string(),
severity: Severity::High,
title: "Potential N+1 query".to_string(),
description: format!("Database query inside loop (started line {})", loop_line),
affected_files: vec![path.to_path_buf()],
line_start: Some((i + 1) as u32),
line_end: Some((i + 1) as u32),
suggested_fix: Some("Use bulk fetch before loop or eager loading.".to_string()),
estimated_effort: Some("45 minutes".to_string()),
category: Some("performance".to_string()),
cwe_id: None,
why_it_matters: Some("Causes N database calls instead of 1.".to_string()),
..Default::default()
});
in_loop = false;
}
}
}
}
}
Ok(findings)
}
}