use std::sync::Arc;

use axum::extract::{Path, State};
use axum::Json;

use crate::api::common::AuthUser;
use crate::error::{ApiError, AppState};
use crate::fs;

/// GET /api/files/{root_id}/{*path}
///
/// List a directory inside one of the user's roots. The wildcard part is the
/// path relative to that root (percent-decoded by axum).
pub async fn list(
    State(state): State<Arc<AppState>>,
    auth: AuthUser,
    path: Path<(i64, String)>,
) -> Result<Json<serde_json::Value>, ApiError> {
    let (root_id, req_rel) = path.0;
    list_inner(state, auth, root_id, req_rel).await
}

/// GET /api/files/{root_id} — list the root directory itself.
pub async fn list_root(
    State(state): State<Arc<AppState>>,
    auth: AuthUser,
    path: Path<i64>,
) -> Result<Json<serde_json::Value>, ApiError> {
    list_inner(state, auth, path.0, String::new()).await
}

async fn list_inner(
    state: Arc<AppState>,
    auth: AuthUser,
    root_id: i64,
    req_rel: String,
) -> Result<Json<serde_json::Value>, ApiError> {
    let root = auth
        .roots
        .iter()
        .find(|r| r.id == root_id)
        .ok_or_else(|| {
            crate::error::ApiError::new(
                axum::http::StatusCode::FORBIDDEN,
                "no such folder",
            )
        })?;

    let server_root = state.root.clone();
    let root_rel = root.path.clone();
    let full = tokio::task::spawn_blocking(move || fs::resolve_path(&server_root, &root_rel, &req_rel))
        .await
        .map_err(|_| ApiError::new(axum::http::StatusCode::INTERNAL_SERVER_ERROR, "internal error"))??;

    let entries = tokio::task::spawn_blocking(move || fs::list_dir(&full))
        .await
        .map_err(|_| ApiError::new(axum::http::StatusCode::INTERNAL_SERVER_ERROR, "internal error"))??;

    Ok(Json(serde_json::json!({ "entries": entries })))
}