import { readFileSync, existsSync } from "node:fs";
import { z } from "zod";

// Minimal .env loader so we don't need an extra dependency.
function loadDotEnv(path = ".env"): void {
  if (!existsSync(path)) return;
  for (const rawLine of readFileSync(path, "utf8").split(/\r?\n/)) {
    const line = rawLine.trim();
    if (!line || line.startsWith("#")) continue;
    const eq = line.indexOf("=");
    if (eq === -1) continue;
    const key = line.slice(0, eq).trim();
    let value = line.slice(eq + 1).trim();
    if (
      (value.startsWith('"') && value.endsWith('"')) ||
      (value.startsWith("'") && value.endsWith("'"))
    ) {
      value = value.slice(1, -1);
    }
    if (process.env[key] === undefined) process.env[key] = value;
  }
}

loadDotEnv();

const schema = z.object({
  STOAT_API_URL: z.string().url(),
  STOAT_BOT_TOKEN: z.string().min(1),
  COMMAND_PREFIX: z.string().min(1).default("!"),
  /** LiveKit node name from Revolt.toml ([hosts.livekit]); self-hosted default is "worldwide". */
  VOICE_NODE: z.string().min(1).default("worldwide"),
  /** Remove the invoking message after a command is recognised. Needs ManageMessages. */
  DELETE_COMMAND_MESSAGES: z
    .enum(["true", "false"])
    .default("true")
    .transform((value) => value === "true"),

  PORT: z.coerce.number().int().positive().default(3005),
  HOST: z.string().default("0.0.0.0"),
  PUBLIC_URL: z.string().url(),
  JWT_SECRET: z.string().min(16),
  SESSION_TTL_HOURS: z.coerce.number().positive().default(168),

  YTDLP_PATH: z.string().default("yt-dlp"),
  YTDLP_COOKIES: z.string().optional(),
  /** Extra `--extractor-args` values, separated by ";" — e.g. youtube:player_client=default,web_safari */
  YTDLP_EXTRACTOR_ARGS: z.string().optional(),
  LOCAL_MEDIA_DIR: z.string().optional(),

  DEFAULT_VOLUME: z.coerce.number().min(0).max(200).default(60),
  MAX_QUEUE_SIZE: z.coerce.number().int().positive().default(500),
  /** Upper bound on how many tracks one pasted playlist may add. */
  MAX_PLAYLIST_TRACKS: z.coerce.number().int().positive().default(100),
  SEARCH_RESULT_LIMIT: z.coerce.number().int().positive().max(25).default(10),
  /** Seconds to wait after the last human leaves the voice channel (0 — never leave). */
  EMPTY_TIMEOUT_SECONDS: z.coerce.number().int().min(0).default(120),
  DJ_ROLE_NAME: z.string().default("DJ"),
  /** Only let people summon the bot into the voice channel they are sitting in. */
  REQUIRE_LISTENER: z
    .enum(["true", "false"])
    .default("true")
    .transform((value) => value === "true"),
  REQUIRE_DJ_ROLE: z
    .enum(["true", "false"])
    .default("false")
    .transform((value) => value === "true"),

  LOG_LEVEL: z.string().default("info"),
  NODE_ENV: z.string().default("development"),
});

const parsed = schema.safeParse(process.env);

if (!parsed.success) {
  const issues = parsed.error.issues
    .map((i) => `  - ${i.path.join(".")}: ${i.message}`)
    .join("\n");
  console.error(`Invalid configuration, check your .env file:\n${issues}`);
  process.exit(1);
}

export const config = {
  ...parsed.data,
  STOAT_API_URL: parsed.data.STOAT_API_URL.replace(/\/+$/, ""),
  PUBLIC_URL: parsed.data.PUBLIC_URL.replace(/\/+$/, ""),
  isProduction: parsed.data.NODE_ENV === "production",
};

export type Config = typeof config;