import { BackendModule, InitOptions, ReadCallback, Services } from "i18next";

export namespace i18next {
    interface InitOptions {
        backend?: i18nextFsBackend.i18nextFsBackendOptions | undefined;
    }
}

export namespace i18nextFsBackend {
    type loadPathFunction = (language: string, namespace: string) => string;

    interface i18nextFsBackendOptions {
        loadPath?: string | loadPathFunction | undefined;
        addPath?: string | undefined;
        ident?: number | undefined;
        parse?: ((data: string) => unknown) | undefined;
        stringify?: ((data: unknown) => string) | undefined;
    }
}

export default class Backend implements BackendModule<i18nextFsBackend.i18nextFsBackendOptions> {
    type: "backend";
    constructor(
        services: Services,
        backendOptions: i18nextFsBackend.i18nextFsBackendOptions,
        i18nextOptions: InitOptions,
    );
    init(
        services: Services,
        backendOptions: i18nextFsBackend.i18nextFsBackendOptions,
        i18nextOptions: InitOptions,
    ): void;
    read(language: string, namespace: string, callback: ReadCallback): void;
    create(languages: string[], namespace: string, key: string, fallbackValue: string): void;

    write(): void;
    writeFile(lng: string, namespace: string): void;
    queue(lng: string, namespace: string, key: string, fallbackValue: string, callback: unknown): void;

    static type: "backend";
}