import { LDClient, LDContext, LDFlagSet, LDOptions } from 'launchdarkly-js-client-sdk';
import * as React from 'react';

/**
 * Initialization options for the LaunchDarkly React SDK. These are in addition to the options exposed
 * by [[LDOptions]] which are common to both the JavaScript and React SDKs.
 */
export interface LDReactOptions {
  /**
   * Whether the React SDK should transform flag keys into camel-cased format.
   * Using camel-cased flag keys allow for easier use as prop values, however,
   * these keys won't directly match the flag keys as known to LaunchDarkly.
   * Consequently, flag key collisions may be possible and the Code References feature
   * will not function properly.
   *
   * This is true by default, meaning that keys will automatically be converted to camel-case.
   *
   * For more information, see the React SDK Reference Guide on
   * [flag keys](https://docs.launchdarkly.com/sdk/client-side/react/react-web#flag-keys).
   *
   * @see https://docs.launchdarkly.com/sdk/client-side/react/react-web#flag-keys
   */
  useCamelCaseFlagKeys?: boolean;

  /**
   * Whether to send flag evaluation events when a flag is read from the `flags` object
   * returned by the `useFlags` hook. This is true by default, meaning flag evaluation
   * events will be sent by default.
   */
  sendEventsOnFlagRead?: boolean;
}

/**
 * Contains default values for the `reactOptions` object.
 */
export const defaultReactOptions = { useCamelCaseFlagKeys: true, sendEventsOnFlagRead: true };

/**
 * Configuration object used to initialise LaunchDarkly's JS client.
 */
export interface ProviderConfig {
  /**
   * Your project and environment specific client side ID. You can find
   * this in your LaunchDarkly portal under Account settings. This is
   * the only mandatory property required to use the React SDK.
   */
  clientSideID: string;

  /**
   * A LaunchDarkly context object. If unspecified, an anonymous context
   * with kind: 'user' will be created and used.
   */
  context?: LDContext;

  /**
   * @deprecated The `user` property will be removed in a future version,
   * please update your code to use context instead.
   */
  user?: LDContext;

  /**
   * If set to true, the ldClient will not be initialized until the context prop has been defined.
   */
  deferInitialization?: boolean;

  /**
   * LaunchDarkly initialization options. These options are common between LaunchDarkly's JavaScript and React SDKs.
   *
   * @see https://docs.launchdarkly.com/sdk/features/config#javascript
   */
  options?: LDOptions;

  /**
   * Additional initialization options specific to the React SDK.
   *
   * @see options
   */
  reactOptions?: LDReactOptions;

  /**
   * If specified, `launchdarkly-react-client-sdk` will only listen for changes to these flags.
   * Otherwise, all flags will be requested and listened to.
   * Flag keys must be in their original form as known to LaunchDarkly rather than in their camel-cased form.
   */
  flags?: LDFlagSet;

  /**
   * Optionally, the ldClient can be initialised outside of the provider
   * and passed in, instead of being initialised by the provider.
   * Note: it should only be passed in when it has emitted the 'ready'
   * event, to ensure that the flags are properly set.
   */
  ldClient?: LDClient | Promise<LDClient | undefined>;
}

/**
 * Configuration object used to initialize LaunchDarkly's JS client asynchronously.
 */
export type AsyncProviderConfig = Omit<ProviderConfig, 'deferInitialization'> & {
  /**
   * @deprecated - `asyncWithLDProvider` does not support the `deferInitialization` config option because
   * `asyncWithLDProvider` needs to be initialized at the app entry point prior to render to ensure flags and the
   * ldClient are ready at the beginning of the app.
   */
  deferInitialization?: boolean;
};

/**
 * The return type of withLDProvider HOC. Exported for testing purposes only.
 *
 * @ignore
 */
export interface EnhancedComponent extends React.Component {
  subscribeToChanges(ldClient: LDClient): void;
  // tslint:disable-next-line:invalid-void
  componentDidMount(): Promise<void>;
  // tslint:disable-next-line:invalid-void
  componentDidUpdate(prevProps: ProviderConfig): Promise<void>;
}

/**
 * Return type of `initLDClient`.
 */
export interface AllFlagsLDClient {
  /**
   * Contains all flags from LaunchDarkly.
   */
  flags: LDFlagSet;

  /**
   * An instance of `LDClient` from the LaunchDarkly JS SDK (`launchdarkly-js-client-sdk`).
   *
   * @see https://docs.launchdarkly.com/sdk/client-side/javascript
   */
  ldClient: LDClient;

  /**
   * LaunchDarkly client initialization error, if there was one.
   */
  error?: Error;
}

/**
 * Map of camelized flag keys to original unmodified flag keys.
 */
export interface LDFlagKeyMap {
  [camelCasedKey: string]: string;
}

export * from 'launchdarkly-js-client-sdk';