//! Finds the Rust files in a tree worth looking at.

use std::path::{Path, PathBuf};

use walkdir::WalkDir;

/// Directories that hold code nobody here wrote, or nothing at all.
const SKIP: &[&str] = &["target", "vendor", "node_modules", ".git", "pkg", "dist"];

/// Every `.rs` file under `root` with at least `min_lines` lines.
pub fn rust_files(root: &Path, min_lines: usize) -> Vec<(PathBuf, usize)> {
    let mut out = Vec::new();
    for entry in WalkDir::new(root)
        .into_iter()
        .filter_entry(|e| {
            !e.file_name()
                .to_str()
                .is_some_and(|n| SKIP.contains(&n) || n.starts_with(".claude"))
        })
        .filter_map(Result::ok)
    {
        if !entry.file_type().is_file() {
            continue;
        }
        if entry.path().extension().and_then(|e| e.to_str()) != Some("rs") {
            continue;
        }
        let Ok(text) = std::fs::read_to_string(entry.path()) else {
            continue;
        };
        let lines = text.lines().count();
        if lines >= min_lines {
            out.push((entry.into_path(), lines));
        }
    }
    out.sort();
    out
}