/**
 * The debug renderers of `value-debug`, as this package's own modules reach
 * them: each function here forwards to the renderer of the same name, which
 * `value-debug` hands over when it loads. A module of this package imports them
 * as `@/value-debug`.
 *
 * This module imports nothing at run time, so a module anywhere in the package
 * can import it without causing a circular load-time dependency.
 *
 * A renderer works once `value-debug` has loaded, and throws before then. A
 * program which imports the package has it loaded, whichever entry of the
 * export map it imports, other than an entry which renders nothing. A unit test
 * which imports one module by its path may not, and gets it by importing
 * `@/for-testing-only.ts`.
 */

import type * as valueDebug from "@/value-debug/index.ts";

/** The renderers `value-debug` installs, by the names it exports them under. */
export type DebugRenderers = Pick<
  typeof valueDebug,
  | "debugStr"
  | "toCompactDebugString"
  | "toDebugKindString"
  | "toIndentedDebugString"
  | "toLongQuotedDebugString"
  | "toShortQuotedDebugString"
  | "toStructuredDebugValue"
>;

/** The installed renderers, or `undefined` until `value-debug` has loaded. */
let installedRenderers: DebugRenderers | undefined;

/**
 * Installs the renderers the functions of this module forward to. `value-debug`
 * calls this as it loads, and nothing else does.
 */
export function installDebugRenderers(renderers: DebugRenderers): void {
  installedRenderers = renderers;
}

/**
 * Whether the renderers are installed, which they are once `value-debug` has
 * loaded.
 */
export function areDebugRenderersInstalled(): boolean {
  return installedRenderers !== undefined;
}

/**
 * Returns the installed renderers.
 *
 * @throws {Error} if `value-debug` has not been loaded.
 */
function renderers(): DebugRenderers {
  if (installedRenderers === undefined) {
    throw new Error(
      "The debug renderers are not installed: nothing has loaded " +
        "`value-debug`. A unit test gets them by importing " +
        "`@/for-testing-only.ts`.",
    );
  }

  return installedRenderers;
}

/** Forwards to `debugStr` of `value-debug`. */
export const debugStr: DebugRenderers["debugStr"] = (strings, ...values) =>
  renderers().debugStr(strings, ...values);

/** Forwards to `toCompactDebugString()` of `value-debug`. */
export const toCompactDebugString: DebugRenderers["toCompactDebugString"] = (
  value,
  options,
) => renderers().toCompactDebugString(value, options);

/** Forwards to `toDebugKindString()` of `value-debug`. */
export const toDebugKindString: DebugRenderers["toDebugKindString"] = (
  value,
) => renderers().toDebugKindString(value);

/** Forwards to `toIndentedDebugString()` of `value-debug`. */
export const toIndentedDebugString: DebugRenderers["toIndentedDebugString"] = (
  value,
  options,
) => renderers().toIndentedDebugString(value, options);

/** Forwards to `toLongQuotedDebugString()` of `value-debug`. */
export const toLongQuotedDebugString:
  DebugRenderers["toLongQuotedDebugString"] = (value) =>
    renderers().toLongQuotedDebugString(value);

/** Forwards to `toShortQuotedDebugString()` of `value-debug`. */
export const toShortQuotedDebugString:
  DebugRenderers["toShortQuotedDebugString"] = (value) =>
    renderers().toShortQuotedDebugString(value);

/** Forwards to `toStructuredDebugValue()` of `value-debug`. */
export const toStructuredDebugValue: DebugRenderers["toStructuredDebugValue"] =
  (value, options) => renderers().toStructuredDebugValue(value, options);