// This file contains some utility types that either can't be expressed in
// JSDoc syntax or that result in a different behaviour when typed in JSDoc.

/**
 * Utility type that takes IPFS Core API function type (with 0 to 4 arguments
 * & last **optional** `options` parameter) and derives a function type with
 * `options` parameter extended with given `Extra` options.
 *
 * **Caution**: API Functions with more than for arguments ahead of `options`
 * will result to `never` type. API function that does not take `options` will
 * result in function whose last argument is extended with `Extra` which would
 * be an error.
 */
// This is typed in TS file because otherwise TS unifies on the first parameter
// regardless of number of parameters function has.
export interface APIWithExtraOptions<API extends (...args: any[]) => any, Extra> { (...args: WithExtendedOptions<Parameters<API>, Extra>): ReturnType<API> }

type End = never[]
type WithExtendedOptions<Params, Ext> = Params extends [...End]
  ? []
  // (options?: Options) -> (options?: Options & Ext)
  : Params extends [options?: infer Options, ...end: End]
    ? [options?: Options & Ext]
  // (a: A1, options?: Options) -> (a1: A1, options?: Options & Ext)
    : Params extends [a1: infer A1, options?: infer Options, ...end: End]
      ? [a1: A1, options?: Options & Ext]
    // (a1?: A1, options?: Options) -> (a1?: A1, options?: Options & Ext)
      : Params extends [a1?: infer A1, options?: infer Options, ...end: End]
        ? [a1?: A1, options?: Options & Ext]
      // (a1: A1, a2: A2, options?: Options) -> (a1: A1, a2: A2 options?: Options & Ext)
        : Params extends [a1: infer A1, a2: infer A2, options?: infer Options, ...end: End]
          ? [a1: A1, a2: A2, options?: Options & Ext]
        // (a1: A1, a2?: A2, options?: Options) -> (a1: A1, a2?: A2 options?: Options & Ext)
          : Params extends [a1: infer A1, a2?: infer A2, options?: infer Options, ...end: End]
            ? [a1: A1, a2?: A2, options?: Options & Ext]
          // (a1: A1, a2?: A2, options?: Options) -> (a1: A1, a2?: A2 options?: Options & Ext)
            : Params extends [a1?: infer A1, a2?: infer A2, options?: infer Options, ...end: End]
              ? [a1?: A1, a2?: A2, options?: Options & Ext]
            // (a1: A1, a2: A2, a3:A3 options?: Options) -> (a1: A1, a2: A2, a3:A3, options?: Options & Ext)
              : Params extends [a1: infer A1, a2: infer A2, a3:infer A3, options?: infer Options, ...end: End]
                ? [a1: A1, a2: A2, a3: A3, options?: Options & Ext]
              // (a1: A1, a2: A2, a3?:A3 options?: Options) -> (a1: A1, a2: A2, a3?:A3, options?: Options & Ext)
                : Params extends [a1: infer A1, a2:infer A2, a3?: infer A3, options?: infer Options, ...end: End]
                  ? [a1: A1, a2: A2, a3?: A3, options?: Options & Ext]
                // (a1: A1, a2?: A2, a3?:A3 options?: Options) -> (a1: A1, a2?: A2, a3?:A3, options?: Options & Ext)
                  : Params extends [a1: infer A1, a2?: infer A2, a3?: infer A3, options?: infer Options, ...end: End]
                    ? [a1: A1, a2?: A2, a3?: A3, options?: Options & Ext]
                  // (a1?: A1, a2?: A2, a3?:A3 options?: Options) -> (a1?: A1, a2?: A2, a3?:A3, options?: Options & Ext)
                    : Params extends [a1?: infer A1, a2?: infer A2, a3?: infer A3, options?: infer Options, ...end: End]
                      ? [a1?: A1, a2?: A2, a3?: A3, options?: Options & Ext]
                      : never

export type APIMethodWithExtraOptions <
  API,
  Key extends keyof API,
  Extra
> = API[Key] extends (...args: any[]) => any ? APIWithExtraOptions<API[Key], Extra> : never