// Copyright 2022 Luca Casonato. All rights reserved. MIT license.
/**
 * Web Fonts Developer API Client for Deno
 * =======================================
 * 
 * The Google Web Fonts Developer API lets you retrieve information about web fonts served by Google.
 * 
 * Docs: https://developers.google.com/fonts/docs/developer_api
 * Source: https://googleapis.deno.dev/v1/webfonts:v1.ts
 */

import { auth, CredentialsClient, GoogleAuth, request } from "/_/base@v1/mod.ts";
export { auth, GoogleAuth };
export type { CredentialsClient };

/**
 * The Google Web Fonts Developer API lets you retrieve information about web
 * fonts served by Google.
 */
export class WebFonts {
  #client: CredentialsClient | undefined;
  #baseUrl: string;

  constructor(client?: CredentialsClient, baseUrl: string = "https://webfonts.googleapis.com/") {
    this.#client = client;
    this.#baseUrl = baseUrl;
  }

  /**
   * Retrieves the list of fonts currently served by the Google Fonts Developer
   * API.
   *
   */
  async webfontsList(opts: WebfontsListOptions = {}): Promise<WebfontList> {
    const url = new URL(`${this.#baseUrl}v1/webfonts`);
    if (opts.capability !== undefined) {
      url.searchParams.append("capability", String(opts.capability));
    }
    if (opts.family !== undefined) {
      url.searchParams.append("family", String(opts.family));
    }
    if (opts.sort !== undefined) {
      url.searchParams.append("sort", String(opts.sort));
    }
    if (opts.subset !== undefined) {
      url.searchParams.append("subset", String(opts.subset));
    }
    const data = await request(url.href, {
      client: this.#client,
      method: "GET",
    });
    return data as WebfontList;
  }
}

/**
 * Metadata for a variable font axis.
 */
export interface Axis {
  /**
   * maximum value
   */
  end?: number;
  /**
   * minimum value
   */
  start?: number;
  /**
   * tag name.
   */
  tag?: string;
}

/**
 * Metadata describing a family of fonts.
 */
export interface Webfont {
  /**
   * Axis for variable fonts.
   */
  axes?: Axis[];
  /**
   * The category of the font.
   */
  category?: string;
  /**
   * The color format(s) available for this family.
   */
  colorCapabilities?: string[];
  /**
   * The name of the font.
   */
  family?: string;
  /**
   * The font files (with all supported scripts) for each one of the available
   * variants, as a key : value map.
   */
  files?: {
    [key: string]: string
  };
  /**
   * This kind represents a webfont object in the webfonts service.
   */
  kind?: string;
  /**
   * The date (format "yyyy-MM-dd") the font was modified for the last time.
   */
  lastModified?: string;
  /**
   * Font URL for menu subset, a subset of the font that is enough to display
   * the font name
   */
  menu?: string;
  /**
   * The scripts supported by the font.
   */
  subsets?: string[];
  /**
   * The available variants for the font.
   */
  variants?: string[];
  /**
   * The font version.
   */
  version?: string;
}

/**
 * Response containing the list of fonts currently served by the Google Fonts
 * API.
 */
export interface WebfontList {
  /**
   * The list of fonts currently served by the Google Fonts API.
   */
  items?: Webfont[];
  /**
   * This kind represents a list of webfont objects in the webfonts service.
   */
  kind?: string;
}

/**
 * Additional options for WebFonts#webfontsList.
 */
export interface WebfontsListOptions {
  /**
   * Controls the font urls in `Webfont.files`, by default, static ttf fonts
   * are sent.
   */
  capability?:  | "CAPABILITY_UNSPECIFIED" | "WOFF2" | "VF";
  /**
   * Filters by Webfont.family, using literal match. If not set, returns all
   * families
   */
  family?: string;
  /**
   * Enables sorting of the list.
   */
  sort?:  | "SORT_UNDEFINED" | "ALPHA" | "DATE" | "POPULARITY" | "STYLE" | "TRENDING";
  /**
   * Filters by Webfont.subset, if subset is found in Webfont.subsets. If not
   * set, returns all families.
   */
  subset?: string;
}