//! Pre-cutover audit utility for the filename date class (ticket #117).
//!
//! One-shot, operator-run: lists every file matching a filename-class
//! pattern across the configured libraries — the file's current stored
//! date + source and the date / source / offset-source the re-based
//! resolver would assign it. Strictly read-only: it changes nothing.
//!
//! This is the human spot-check that gates the production backfill
//! drain: review the report, fix any mis-tagged pattern or
//! misclassified file, then start the drain.
//!
//! Usage: `cargo run --bin filename_audit` (reads DATABASE_URL and
//! EXCLUDED_DIRS from the environment, like the server).

use std::path::PathBuf;

use diesel::Connection;
use diesel::sqlite::SqliteConnection;
use image_api::filename_audit::{format_report, run_audit};
use image_api::libraries::load_all;

fn main() -> anyhow::Result<()> {
    env_logger::init();
    dotenv::dotenv().ok();

    let database_url = dotenv::var("DATABASE_URL")
        .map_err(|_| anyhow::anyhow!("DATABASE_URL is not set (check .env)"))?;
    let base_path = dotenv::var("BASE_PATH").ok();

    let mut conn =
        SqliteConnection::establish(&database_url).map_err(|e| anyhow::anyhow!(e.to_string()))?;

    // Migrations are already run by the server; the audit only SELECTs.
    // A fresh database without the date-class columns would fail the
    // select below with a clear SQL error — that is the expected signal.

    let global_excludes: Vec<String> = dotenv::var("EXCLUDED_DIRS")
        .unwrap_or_default()
        .split(',')
        .map(str::trim)
        .filter(|s| !s.is_empty())
        .map(String::from)
        .collect();

    let libraries = load_all(&mut conn);
    if libraries.is_empty() {
        anyhow::bail!(
            "no rows in the `libraries` table — is DATABASE_URL pointing at the live database?"
        );
    }

    // BASE_PATH is informational for the operator (the libraries table
    // carries the authoritative roots); warn when it differs from every
    // known root so a stale env var doesn't mislead the review.
    if let Some(base) = &base_path
        && let base = PathBuf::from(base)
        && !libraries
            .iter()
            .any(|l| std::path::Path::new(&l.root_path) == base)
    {
        eprintln!(
            "note: BASE_PATH ({}) does not match any library root; auditing the library table",
            base.display()
        );
    }

    println!("Filename date class audit (read-only)");
    println!("======================================");
    println!("Libraries: {}", libraries.len());
    println!();

    let (rows, skipped) = run_audit(&mut conn, libraries, &global_excludes);
    print!("{}", format_report(&rows, &skipped));

    Ok(())
}