/**
 * Central configuration — the ONE place the SDK reads environment.
 *
 * Values come from node-config (a package's `config/` dir: `default.json` for
 * defaults + `custom-environment-variables.json` mapping env vars → keys), which
 * is the single declarative place every env var is documented. If a package
 * ships no config/ (or a key isn't mapped), we fall back to the raw env var and
 * then a built-in default — so the SDK works with or without node-config.
 *
 * Nothing else in the SDK touches `process.env`. Import { cfg } from here.
 */

import config from "config";

// read resolves a value in priority order: node-config → raw env var → default.
// This module is the only place `process.env` is read.
function read(key: string, envVar: string, fallback = ""): string {
  try {
    if (config.has(key)) {
      const v = config.get(key);
      if (v != null && v !== "") return String(v);
    }
  } catch {
    // node-config not configured for this process (no config/ dir) — fall through.
  }
  return process.env[envVar] ?? fallback;
}

export const cfg = {
  /** Platform API base URL. env: NP_API_URL */
  apiUrl: () => read("api.url", "NP_API_URL", "https://api.nullplatform.com"),

  /** Platform API key. env: NP_API_KEY */
  apiKey: () => read("api.key", "NP_API_KEY"),

  /** Executions/streaming API URL. env: NP_EXECUTIONS_API_URL */
  executionsApiUrl: () => read("api.executionsUrl", "NP_EXECUTIONS_API_URL"),

  /** Agent transport mode marker. env: NP_AGENT_PLUGIN */
  agentMode: () => read("agent.mode", "NP_AGENT_PLUGIN"),

  /**
   * When set, the gRPC server listens on this TCP address (e.g. ":50051") instead
   * of a unix socket + go-plugin handshake. Used when the worker runs as its own
   * pod/container and the orchestrating agent dials it over the network.
   * env: NP_GRPC_LISTEN
   */
  grpcListen: () => read("agent.grpcListen", "NP_GRPC_LISTEN"),

  /**
   * Execution mode: "dev" | "test" | "" (production/agent). Set explicitly by
   * `np package dev` / `np package test`. When "dev" or "test" the SDK uses the
   * in-memory platform client and NEVER touches the real API — even if an API
   * key is present in the environment. env: NP_MODE
   */
  mode: () => read("mode", "NP_MODE"),

  /** The action payload injected in subprocess-exec mode. env: NP_ACTION_CONTEXT */
  actionContext: () => read("agent.actionContext", "NP_ACTION_CONTEXT"),

  /** Tracing API base URL; tracing is off when empty. env: NP_TRACING_URL */
  tracingUrl: () => read("tracing.url", "NP_TRACING_URL"),

  /** Path to a plugin manifest override. env: NP_PLUGIN_MANIFEST */
  pluginManifest: () => read("plugin.manifest", "NP_PLUGIN_MANIFEST"),
} as const;