/**
 * Frontend logger with configurable level (window.__DT_LOG_LEVEL).
 * Only messages at or above the configured level are forwarded to console.
 * Prefix [DutyTeller][level] for DevTools filtering.
 */

const LEVEL_ORDER = { debug: 0, info: 1, warn: 2, error: 3 };

/**
 * Resolve current log level from window.__DT_LOG_LEVEL. Default: info.
 * @returns {string} One of "debug", "info", "warn", "error"
 */
function getLogLevel() {
  const raw =
    (typeof window !== "undefined" && window.__DT_LOG_LEVEL) || "info";
  const level = String(raw).toLowerCase();
  return LEVEL_ORDER.hasOwnProperty(level) ? level : "info";
}

/**
 * Return true if message at level should be emitted (level >= configured).
 * @param {string} messageLevel - "debug" | "info" | "warn" | "error"
 * @returns {boolean}
 */
function shouldLog(messageLevel) {
  const configured = getLogLevel();
  const configuredNum = LEVEL_ORDER[configured] ?? 1;
  const messageNum = LEVEL_ORDER[messageLevel] ?? 1;
  return messageNum >= configuredNum;
}

const PREFIX = "[DutyTeller]";

function logAt(level, args) {
  if (!shouldLog(level)) return;
  const consoleMethod =
    level === "debug"
      ? console.debug
      : level === "info"
        ? console.info
        : level === "warn"
          ? console.warn
          : console.error;
  const prefix = `${PREFIX}[${level}]`;
  if (args.length === 0) {
    consoleMethod(prefix);
  } else if (args.length === 1) {
    consoleMethod(prefix, args[0]);
  } else {
    consoleMethod(prefix, ...args);
  }
}

/**
 * Logger object with debug, info, warn, error (signature like console).
 * Example: logger.info("Loaded", { count: 5 });
 */
export const logger = {
  debug(msg, ...args) {
    logAt("debug", [msg, ...args]);
  },
  info(msg, ...args) {
    logAt("info", [msg, ...args]);
  },
  warn(msg, ...args) {
    logAt("warn", [msg, ...args]);
  },
  error(msg, ...args) {
    logAt("error", [msg, ...args]);
  },
};