import * as nightwatch from "nightwatch";

declare module "nightwatch" {
    export interface NightwatchVRTSettings {
      "baseline_screenshots_path"?: string;
      "baseline_suffix"?: string;
      "latest_screenshots_path"?: string;
      "latest_suffix"?: string;
      "diff_screenshots_path"?: string;
      "diff_suffix"?: string;
      "threshold"?: number;
      "screenshotPath": (browser: NightwatchAPI) => string;
      "prompt"?: boolean;
    }

    export interface NightwatchAssertions {
        /**
         * Asserts if a screenshot that captures the visual representation of
         * an element in the application is identical to a previously captured
         * screenshot used as a baseline.
         *
         * When this assertion is executed and the baseline screenshot doesn't exists,
         * it will use save captured screenshot as the baseline and the assertion will succeed.
         *
         * The baseline screenshot will be saved in the baseline directory passed in
         * the settings, or the directory specified in the nightwatch configuration
         * (under test_settings/visual_regression_settings), or in a default generated path; in
         * that order. Further assertions will compare against the screenshot that was
         * saved in the first execution of the assertion.
         *
         * @param {String} elementId Identifies the element that will be captured in the screenshot.
         * @param {String} fileName Optional file name for this screenshot; defaults to the selector
         * @param {NightwatchVRTOptions} settings Optional settings to override the defaults and `visual_regression_settings`
         * @param {String} message Optional message for `nightwatch` to log upon completion
         */
        screenshotIdenticalToBaseline: (elementId: string, fileName?: string, options?: NightwatchVRTSettings, message?: string) => this;
    }

    export interface NightwatchAPI {
        /**
         * Takes a screenshot of the visible region encompassed by the bounding rectangle
         * of an element.
        *
         * @link
         * @param {string} selector Identifies the element that will be captured in the screenshot.
         * @param {function} callback Callback function which is called with the captured screenshot as an argument.
         * @returns {Object} The captured screenshot. This object is a Jimp (library) image instance.
         */
        captureElementScreenshot: (elementId: string, callback?: (arg?: any) => void) => this
    }
}