import {Awaitable, JSONState, Maybe, Rehydratable} from '../util'

/** Value that can be used to uniquely identify a user. */
export type AuthenticatableIdentifier = string | number

export interface AuthenticatableCredentials {
    identifier: string,
    credential: string,
}

/**
 * Base class for entities that can be authenticated.
 */
export abstract class Authenticatable implements Rehydratable {

    /** Get the unique identifier of the user. */
    abstract getIdentifier(): AuthenticatableIdentifier

    /** Get the human-readable identifier of the user. */
    abstract getDisplayIdentifier(): string

    abstract dehydrate(): Promise<JSONState>

    abstract rehydrate(state: JSONState): Awaitable<void>
}

/**
 * Base class for a repository that stores and recalls users.
 */
export abstract class AuthenticatableRepository {

    /** Look up the user by their unique identifier. */
    abstract getByIdentifier(id: AuthenticatableIdentifier): Awaitable<Maybe<Authenticatable>>

    /**
     * Attempt to look up and verify a user by their credentials.
     * Returns the user if the credentials are valid.
     * @param credentials
     */
    abstract getByCredentials(credentials: AuthenticatableCredentials): Awaitable<Maybe<Authenticatable>>

    abstract createByCredentials(credentials: AuthenticatableCredentials): Awaitable<Authenticatable>
}