//! # main.rs — BEDS Entry Point
//!
//! Application entry point. Invokes the IPL (Initial Program Load) sequence
//! which bootstraps all required services before the node enters its
//! operational state.
//!
//! ## Calling Agents
//! None — this is the process entry point.
//!
//! ## Inputs
//! - `BEDS_ENV` environment variable selects the env config file (default: dev)
//!
//! ## Outputs
//! - Running BEDS node, blocked on signal handler (not yet implemented)
//! - On fatal IPL failure: error output to console, process exits non-zero
//!
//! **Author:** ms
//! **Version:** 1.0
//!
//! ## History
//! * `2026-04-02` - mks - original coding
//! * `2026-04-02` - mks - refactored startup sequence into ipl()

mod amqp;
mod config;
mod logging;

/// Executes the BEDS Initial Program Load (IPL) sequence.
///
/// IPL bootstraps the node in strict order. Each step must succeed before
/// the next is attempted. In production environments, any failure is fatal
/// and the process exits with a console error report. In development
/// environments, non-critical failures are logged and IPL continues.
///
/// ## IPL Sequence
/// 1. Load configuration (beds.toml + env override)
/// 2. Initialize logging
/// 3. Connect to required services (AMQP, store adapters) — not yet implemented
/// 4. Declare queues based on node role — not yet implemented
/// 5. Node green
///
/// # Returns
///
/// `Ok(())` if all required services are available and the node is ready.
/// `Err(String)` with a descriptive error message if IPL cannot complete.
///
/// # History
///
/// * `2026-04-02` - mks - original coding
fn ipl() -> Result<(), String> {
    // load configuration — fatal in all environments if this fails
    let cfg = config::load().map_err(|e| format!("Failed to load config: {}", e))?;

    // initialize logging — must come before any tracing calls
    logging::init_from_config(cfg.syslog, cfg.syslog_mirror_console);

    tracing::info!("BEDS IPL starting, node={} env={}", cfg.id.wbid, cfg.id.env_name);
    tracing::info!("Configuration loaded");
    tracing::info!("Logging initialized");

    // validate broker reachability — fatal in production, non-fatal in all other envs
    match amqp::validate(&cfg.broker_services) {
        Ok(()) => tracing::info!("RabbitMQ reachable"),
        Err(e) => {
            if cfg.id.env_name == "production" {
                return Err(e);
            }
            tracing::warn!("RabbitMQ unreachable (non-fatal in {}): {}", cfg.id.env_name, e);
        }
    }

    Ok(())
}

fn main() {
    if let Err(e) = ipl() {
        eprintln!("[BEDS] [FATAL] [IPL] {}", e);
        std::process::exit(1);
    }
}