import { NOTIFY_ENV } from "./constants.ts";

export type Toggle = "on" | "off";

function parseToggle(value: unknown): Toggle | undefined {
  if (typeof value !== "string") return undefined;
  const normalized = value.trim().toLowerCase();
  return normalized === "on" || normalized === "1" || normalized === "true" ? "on" :
    normalized === "off" || normalized === "0" || normalized === "false" ? "off" : undefined;
}

export interface FlagReader {
  getFlag(name: string): boolean | string | undefined;
}

export function resolveToggle(
  flag: unknown,
  env: unknown,
  fallback: Toggle,
): Toggle {
  return parseToggle(flag) ?? parseToggle(env) ?? fallback;
}

export function resolveNotificationConfig(
  flags: FlagReader,
  env: Readonly<Record<string, string | undefined>> = process.env,
): { completion: Toggle; error: Toggle; tool: Toggle } {
  return {
    completion: resolveToggle(flags.getFlag("notify-completion"), env[NOTIFY_ENV.completion], "on"),
    error: resolveToggle(flags.getFlag("notify-error"), env[NOTIFY_ENV.error], "on"),
    tool: resolveToggle(flags.getFlag("notify-tool"), env[NOTIFY_ENV.tool], "off"),
  };
}