use anyhow::{Context, Result};
use serde::de::DeserializeOwned;
use std::path::Path;

#[allow(dead_code)]
/// Generic loader for JSON arrays from a directory.
pub fn load_json_dir<T: DeserializeOwned>(dir: &Path) -> Result<Vec<T>> {
    let mut items = Vec::new();
    if !dir.exists() {
        return Ok(items);
    }
    for entry in std::fs::read_dir(dir).with_context(|| format!("reading dir {dir:?}"))? {
        let entry = entry?;
        let path = entry.path();
        if path.extension().map(|e| e == "json").unwrap_or(false) {
            let content =
                std::fs::read_to_string(&path).with_context(|| format!("reading {path:?}"))?;
            let batch: Vec<T> =
                serde_json::from_str(&content).with_context(|| format!("parsing {path:?}"))?;
            items.extend(batch);
        }
    }
    Ok(items)
}