/**
 * <div style={{backgroundColor: "#000", display: "flex", justifyContent: "space-between", color: "#fff", padding: 16}}>
 * <span>Built-in <b>Twitch</b> integration.</span>
 * <a href="https://www.twitch.tv/">
 *   <img style={{display: "block"}} src="https://authjs.dev/img/providers/twitch.svg" height="48" />
 * </a>
 * </div>
 *
 * @module providers/twitch
 */
import type { OIDCConfig, OIDCUserConfig } from "./index.js"

export interface TwitchProfile extends Record<string, any> {
  sub: string
  preferred_username: string
  email: string
  picture: string
}

/**
 * Add Twitch login to your page.
 *
 * ### Setup
 *
 * #### Callback URL
 * ```
 * https://example.com/api/auth/callback/twitch
 * ```
 *
 * #### Configuration
 *```ts
 * import { Auth } from "@auth/core"
 * import Twitch from "@auth/core/providers/twitch"
 *
 * const request = new Request(origin)
 * const response = await Auth(request, {
 *   providers: [
 *     Twitch({ clientId: TWITCH_CLIENT_ID, clientSecret: TWITCH_CLIENT_SECRET }),
 *   ],
 * })
 * ```
 *
 * ### Resources
 *
 * - [Twitch app documentation](https://dev.twitch.tv/console/apps)
 *
 * Add the following redirect URL into the console `http://<your-next-app-url>/api/auth/callback/twitch`
 *
 *
 * ### Notes
 *
 * By default, Auth.js assumes that the Twitch provider is
 * based on the [Open ID Connect](https://openid.net/specs/openid-connect-core-1_0.html) specification.
 *
 * :::tip
 *
 * The Twitch provider comes with a [default configuration](https://github.com/nextauthjs/next-auth/blob/main/packages/core/src/providers/twitch.ts).
 * To override the defaults for your use case, check out [customizing a built-in OAuth provider](https://authjs.dev/guides/configuring-oauth-providers).
 *
 * :::
 *
 * :::info **Disclaimer**
 *
 * If you think you found a bug in the default configuration, you can [open an issue](https://authjs.dev/new/provider-issue).
 *
 * Auth.js strictly adheres to the specification and it cannot take responsibility for any deviation from
 * the spec by the provider. You can open an issue, but if the problem is non-compliance with the spec,
 * we might not pursue a resolution. You can ask for more help in [Discussions](https://authjs.dev/new/github-discussions).
 *
 * :::
 */
export default function Twitch(
  config: OIDCUserConfig<TwitchProfile>
): OIDCConfig<TwitchProfile> {
  return {
    issuer: "https://id.twitch.tv/oauth2",
    id: "twitch",
    name: "Twitch",
    type: "oidc",
    client: { token_endpoint_auth_method: "client_secret_post" },
    authorization: {
      params: {
        scope: "openid user:read:email",
        claims: {
          id_token: { email: null, picture: null, preferred_username: null },
        },
      },
    },
    token: {
      async conform(response) {
        const body = await response.json()
        if (response.ok) {
          if (typeof body.scope === "string") {
            console.warn(
              "'scope' is a string. Redundant workaround, please open an issue."
            )
          } else if (Array.isArray(body.scope)) {
            body.scope = body.scope.join(" ")
            return new Response(JSON.stringify(body), response)
          } else if ("scope" in body) {
            delete body.scope
            return new Response(JSON.stringify(body), response)
          }
        } else {
          const { message: error_description, error } = body
          if (typeof error !== "string") {
            return new Response(
              JSON.stringify({ error: "invalid_request", error_description }),
              response
            )
          }
          console.warn(
            "Response has 'error'. Redundant workaround, please open an issue."
          )
        }
      },
    },
    style: { bg: "#65459B", text: "#fff" },
    options: config,
  }
}