svelte-kit-vice/src/lib/logr/lib/transports.ts

import type { 
    Transport, 
    ConsoleTransportOptions, 
    HttpTransportOptions, 
    LogEntry 
} from './types.ts';

import { LogLevel } from './types.ts';

// ============================================================================
// CONSOLE TRANSPORT
// ============================================================================

/**
 * Transport que emite los logs a la consola del navegador/Node.
 * Es el transport por defecto si no se especifica ninguno en `LogrOptions`.
 *
 * Usa el método de consola apropiado según el nivel:
 * DEBUG → console.debug, INFO → console.info, WARN → console.warn, ERROR → console.error
 *
 * @example
 * createLogr(i18n, { transports: [consoleTransport()] })
 *
 * @example
 * // Sin timestamp ni prefijo
 * consoleTransport({ timestamp: false, prefix: false })
 */
export function consoleTransport(options: ConsoleTransportOptions = {}): Transport {
    const { timestamp: showTimestamp = true, prefix: showPrefix = true } = options;

    return {
        write(entry: LogEntry, resolvedMessage: string): void {
            const args: unknown[] = [];

            if (showTimestamp) args.push(entry.timestamp.toISOString());
            if (showPrefix)    args.push(`[${entry.category}]`);
            args.push(resolvedMessage);

            // Solo añade el contexto si existe — evita un '' vacío al final de cada línea
            if (entry.context) args.push(entry.context);

            switch (entry.level) {
                case LogLevel.DEBUG: console.debug(...args as [unknown, ...unknown[]]); break;
                case LogLevel.INFO:  console.info (...args as [unknown, ...unknown[]]); break;
                case LogLevel.WARN:  console.warn (...args as [unknown, ...unknown[]]); break;
                case LogLevel.ERROR: console.error(...args as [unknown, ...unknown[]]); break;
            }
        }
    };
}

// ============================================================================
// HTTP TRANSPORT
// ============================================================================

/**
 * Transport que envía las entradas de log a un endpoint HTTP remoto via POST.
 * Útil para servicios de logging centralizados (Datadog, Logtail, custom APIs...).
 *
 * El envío es fire-and-forget — los errores de red se loguean en consola
 * pero no interrumpen el flujo de la aplicación.
 *
 * Nota: no incluye retry ni batching. Para alto volumen considera un transport
 * personalizado con cola y reintentos.
 *
 * @example
 * httpTransport({
 *     url    : 'https://logs.myapp.com/ingest',
 *     headers: { 'Authorization': 'Bearer my-token' },
 *     level  : LogLevel.ERROR
 * })
 */
export function httpTransport(options: HttpTransportOptions): Transport {
    // Usa la constante del enum en lugar del magic number 3
    const minLevel = options.level ?? LogLevel.ERROR;

    return {
        write(entry: LogEntry, resolvedMessage: string): void {
            if (entry.level < minLevel) return;

            const payload = {
                timestamp: entry.timestamp.toISOString(),
                level    : entry.level,
                category : entry.category,
                message  : resolvedMessage,
                context  : entry.context,
            };

            // Fire-and-forget — no bloqueamos el hilo principal
            fetch(options.url, {
                method : 'POST',
                headers: {
                    'Content-Type': 'application/json',
                    ...options.headers,
                },
                body: JSON.stringify(payload),
            }).catch(err => {
                console.error('[logr:httpTransport] Failed to send log:', err);
            });
        }
    };
}

// ============================================================================
// CALLBACK TRANSPORT
// ============================================================================

/**
 * Transport que invoca una función callback por cada entrada de log.
 * Es el transport más flexible — ideal para integraciones custom,
 * tests, o cuando necesitas lógica de routing entre destinos.
 *
 * @example
 * // Integración con Sentry
 * callbackTransport((entry, message) => {
 *     if (entry.level >= LogLevel.ERROR) {
 *         Sentry.captureMessage(message, { extra: entry.context });
 *     }
 * })
 *
 * @example
 * // En tests — captura los logs sin output a consola
 * const captured: string[] = [];
 * callbackTransport((_, message) => captured.push(message))
 */
export function callbackTransport(
    fn: (entry: LogEntry, resolvedMessage: string) => void
): Transport {
    return { write: fn };
}