/**
 * Centralized environment variable access with validation.
 *
 * All runtime environment variables should be accessed through this module
 * instead of reading process.env directly. This provides:
 * - Single source of truth for env var names and defaults
 * - Type-safe accessors (string, number, boolean)
 * - Fail-fast validation via validateEnv() at startup
 * - Shared derived values (e.g. gateway base URL) instead of duplicated logic
 *
 * Bootstrap-level env vars (IS_CONTAINERIZED, DEBUG_STDOUT_LOGS) are defined
 * in config/env-registry.ts which has no internal dependencies and can be
 * imported from platform/logger without circular imports.
 */

import { getLogger } from "../util/logger.js";
import { checkUnrecognizedEnvVars } from "./env-registry.js";
import { getConfig } from "./loader.js";

const log = getLogger("env");

// ── Helpers ──────────────────────────────────────────────────────────────────

/** Read an env var as a trimmed non-empty string, or undefined. */
function str(name: string): string | undefined {
  const v = process.env[name]?.trim();
  return v || undefined;
}

/** Read an env var as an integer with fallback. Returns undefined if not set and no fallback given. */
function int(name: string, fallback: number): number;
function int(name: string): number | undefined;
function int(name: string, fallback?: number): number | undefined {
  const raw = str(name);
  if (!raw) {
    return fallback;
  }
  const n = parseInt(raw, 10);
  if (isNaN(n)) {
    throw new Error(
      `Invalid integer for ${name}: "${raw}"${
        fallback !== undefined ? ` (fallback: ${fallback})` : ""
      }`,
    );
  }
  return n;
}

// ── Gateway ──────────────────────────────────────────────────────────────────

const DEFAULT_GATEWAY_PORT = 7830;

function getGatewayPort(): number {
  return int("GATEWAY_PORT", DEFAULT_GATEWAY_PORT);
}

/**
 * Resolve the gateway base URL for internal service-to-service calls.
 *
 * In containerized deployments the gateway runs in a separate container,
 * reachable via `GATEWAY_INTERNAL_URL` (e.g. `http://gateway:7822`).
 * Falls back to `http://127.0.0.1:<GATEWAY_PORT>` for local deployments.
 */
export function getGatewayInternalBaseUrl(): string {
  return str("GATEWAY_INTERNAL_URL") ?? `http://127.0.0.1:${getGatewayPort()}`;
}

// ── Ingress ──────────────────────────────────────────────────────────────────

let _ingressPublicBaseUrl: string | undefined;

/** Read the ingress public base URL (module-level state, mutated at runtime by config handlers). */
export function getIngressPublicBaseUrl(): string | undefined {
  return _ingressPublicBaseUrl;
}

/** Set or clear the ingress public base URL (used by config handlers). */
export function setIngressPublicBaseUrl(value: string | undefined): void {
  _ingressPublicBaseUrl = value;
}

// ── Runtime HTTP ─────────────────────────────────────────────────────────────

export function getRuntimeHttpPort(): number {
  return int("RUNTIME_HTTP_PORT") ?? 7821;
}

export function getRuntimeHttpHost(): string {
  return str("RUNTIME_HTTP_HOST") || "127.0.0.1";
}

/**
 * True when HTTP API auth is disabled via DISABLE_HTTP_AUTH=true.
 * Used in platform-managed deployments where the platform handles auth.
 */
export function isHttpAuthDisabled(): boolean {
  return str("DISABLE_HTTP_AUTH")?.toLowerCase() === "true";
}

// ── Qdrant ───────────────────────────────────────────────────────────────────

export function getQdrantUrlEnv(): string | undefined {
  return str("QDRANT_URL");
}

export function getQdrantHttpPortEnv(): number | undefined {
  return int("QDRANT_HTTP_PORT");
}

export function getQdrantReadyzTimeoutMs(): number | undefined {
  return int("QDRANT_READYZ_TIMEOUT_MS");
}

// ── Ollama ───────────────────────────────────────────────────────────────────

export function getOllamaBaseUrlEnv(): string | undefined {
  return str("OLLAMA_BASE_URL");
}

// ── Platform ─────────────────────────────────────────────────────────────────

let _platformBaseUrlOverride: string | undefined;

export function setPlatformBaseUrl(value: string | undefined): void {
  _platformBaseUrlOverride = value;
}

export function getPlatformBaseUrl(): string {
  let configUrl: string | undefined;
  try {
    const val = getConfig().platform.baseUrl;
    if (val) {
      configUrl = val;
    }
  } catch {
    // Config not yet available (early bootstrap) — fall through
  }
  // Resolve the default platform URL from VELLUM_ENVIRONMENT.
  // `production`, `staging`, and `test` map to their respective hosted
  // platforms, `local` points at a developer's locally running platform,
  // and everything else (including unset) falls back to dev-platform.
  const env = str("VELLUM_ENVIRONMENT")?.trim();
  let defaultUrl: string;
  if (env === "production") {
    defaultUrl = "https://platform.vellum.ai";
  } else if (env === "staging") {
    defaultUrl = "https://staging-platform.vellum.ai";
  } else if (env === "test") {
    defaultUrl = "https://test-platform.vellum.ai";
  } else if (env === "local") {
    defaultUrl = "http://localhost:8000";
  } else {
    defaultUrl = "https://dev-platform.vellum.ai";
  }
  return (
    configUrl ||
    str("VELLUM_PLATFORM_URL") ||
    _platformBaseUrlOverride ||
    defaultUrl
  );
}

/**
 * Returns the environment-level apex domain (e.g. "vellum.me",
 * "dev.vellum.me", "staging.vellum.me"). Never includes the
 * assistant-specific subdomain.
 */
export function getApexDomain(): string {
  try {
    const url = getPlatformBaseUrl();
    const host = new URL(url).hostname;

    if (host.endsWith("platform.vellum.ai")) {
      const prefix = host.replace(/[-.]?platform\.vellum\.ai$/, "");
      if (prefix) {
        return `${prefix}.vellum.me`;
      }
      return "vellum.me";
    }

    const env = str("VELLUM_ENVIRONMENT")?.trim();
    if (env && env !== "production") {
      return `${env}.vellum.me`;
    }
    return "local.vellum.me";
  } catch {
    // Fall through to default
  }
  return "vellum.me";
}

export function getAssistantDomain(): string {
  const subdomain = (() => {
    try {
      return getConfig().platform?.subdomain;
    } catch {
      return undefined;
    }
  })();
  const apex = getApexDomain();
  if (subdomain) {
    return `${subdomain}.${apex}`;
  }
  return apex;
}

let _platformAssistantIdOverride: string | undefined;

export function setPlatformAssistantId(value: string | undefined): void {
  _platformAssistantIdOverride = value;
}

/**
 * Platform assistant ID — UUID of this assistant on the platform.
 *
 * Resolved from the in-memory override (populated by providers-setup
 * rehydration from the credential store at daemon startup, or by
 * secret-routes when the platform pushes the value).
 */
export function getPlatformAssistantId(): string {
  return _platformAssistantIdOverride ?? "";
}

let _platformOrganizationIdOverride: string | undefined;

export function setPlatformOrganizationId(value: string | undefined): void {
  _platformOrganizationIdOverride = value;
}

/**
 * PLATFORM_ORGANIZATION_ID — UUID of the organization this assistant belongs to.
 * Used for Sentry tagging and platform API calls.
 */
export function getPlatformOrganizationId(): string {
  return (
    str("PLATFORM_ORGANIZATION_ID") ?? _platformOrganizationIdOverride ?? ""
  );
}

let _platformUserIdOverride: string | undefined;

export function setPlatformUserId(value: string | undefined): void {
  _platformUserIdOverride = value;
}

/**
 * PLATFORM_USER_ID — UUID of the user who owns this assistant.
 * Used for telemetry and platform API calls.
 */
export function getPlatformUserId(): string {
  return str("PLATFORM_USER_ID") ?? _platformUserIdOverride ?? "";
}

// ── Startup validation ──────────────────────────────────────────────────────

/**
 * Validate environment at startup. Call early in daemon lifecycle
 * (after dotenv loads). Throws on invalid required values; warns on
 * deprecated vars.
 */
export function validateEnv(): void {
  const gatewayPort = getGatewayPort();
  if (gatewayPort < 1 || gatewayPort > 65535) {
    throw new Error(`Invalid GATEWAY_PORT: ${gatewayPort} (must be 1-65535)`);
  }

  const httpPort = getRuntimeHttpPort();
  if (httpPort < 1 || httpPort > 65535) {
    throw new Error(`Invalid RUNTIME_HTTP_PORT: ${httpPort} (must be 1-65535)`);
  }

  for (const warning of checkUnrecognizedEnvVars()) {
    log.warn(warning);
  }
}