import BaseDialog from './BaseDialog';

const VB_DIALOG_CONTAINER = '#virtual-background-dialog';
const NONE_THUMBNAIL = '[aria-label="Remove background"]';
const SLIGHT_BLUR_THUMBNAIL = '[aria-label="Half Blur"]';
const BLUR_THUMBNAIL = '[aria-label="Blur"]';

/**
 * Page object for the Virtual Background tab inside the settings dialog.
 */
export default class VirtualBackgroundDialog extends BaseDialog {
    /**
     * Waits for the virtual background dialog container to be displayed.
     */
    async waitForDisplay(): Promise<void> {
        await this.participant.driver.$(VB_DIALOG_CONTAINER).waitForDisplayed({
            timeout: 5000,
            timeoutMsg: 'Virtual background dialog not displayed'
        });
    }

    /**
     * Returns true if the dialog container is currently displayed.
     */
    isDisplayed(): Promise<boolean> {
        return this.participant.driver.$(VB_DIALOG_CONTAINER).isDisplayed();
    }

    /**
     * Clicks a thumbnail and waits for it to become aria-checked.
     * Ensures React has finished re-rendering before the next click, preventing
     * rapid clicks from being swallowed during reconciliation.
     *
     * @param {string} selector - CSS selector for the thumbnail.
     * @param {string} label - Human-readable label for logging.
     */
    private async clickAndWaitChecked(selector: string, label: string): Promise<void> {
        await this.participant.log(`VirtualBackgroundDialog: clicking ${label} thumbnail`);
        const el = this.participant.driver.$(selector);

        await el.waitForClickable({ timeout: 3000, timeoutMsg: `${label} thumbnail not clickable` });

        // Selecting an effect makes the preview (re)load the segmentation model/wasm, which
        // saturates the main thread. Two flaky failure modes follow from that:
        //   1. A click issued while React is mid-reconciliation (e.g. during rapid switching) is
        //      dropped — the onClick handler never fires and the thumbnail never becomes checked.
        //   2. The first selection of a blur effect triggers a cold model/worker init that blocks
        //      the main thread for several seconds, delaying the aria-checked re-render (and the
        //      attribute reads themselves) well past a short timeout.
        // Re-issue the click on every poll until aria-checked confirms it landed (covers 1), and
        // allow a generous timeout for the cold-start re-render under load (covers 2). The poll
        // interval is kept large so a still-pending selection is not needlessly re-triggered.
        await this.participant.driver.waitUntil(
            async () => {
                if (await el.getAttribute('aria-checked') === 'true') {
                    return true;
                }

                await el.click();

                return false;
            },
            {
                timeout: 15000,
                interval: 1500,
                timeoutMsg: `${label} thumbnail did not become checked after click`
            }
        );
    }

    /**
     * Clicks the "Remove background" (None) thumbnail.
     */
    clickNone(): Promise<void> {
        return this.clickAndWaitChecked(NONE_THUMBNAIL, 'None');
    }

    /**
     * Clicks the "Half Blur" (slight blur) thumbnail.
     */
    clickSlightBlur(): Promise<void> {
        return this.clickAndWaitChecked(SLIGHT_BLUR_THUMBNAIL, 'Slight Blur');
    }

    /**
     * Clicks the "Blur" (full blur) thumbnail.
     */
    clickBlur(): Promise<void> {
        return this.clickAndWaitChecked(BLUR_THUMBNAIL, 'Blur');
    }

    /**
     * Returns true if the given thumbnail element has aria-checked="true" (selected in the dialog).
     *
     * @param {string} selector - CSS selector for the thumbnail element.
     */
    async isThumbnailChecked(selector: string): Promise<boolean> {
        const el = this.participant.driver.$(selector);

        await el.waitForExist({ timeout: 2000 });

        return (await el.getAttribute('aria-checked')) === 'true';
    }

    /**
     * Returns true if the None thumbnail is currently selected in the dialog.
     */
    isNoneChecked(): Promise<boolean> {
        return this.isThumbnailChecked(NONE_THUMBNAIL);
    }

    /**
     * Returns true if the Slight Blur thumbnail is currently selected in the dialog.
     */
    isSlightBlurChecked(): Promise<boolean> {
        return this.isThumbnailChecked(SLIGHT_BLUR_THUMBNAIL);
    }

    /**
     * Returns true if the Blur thumbnail is currently selected in the dialog.
     */
    isBlurChecked(): Promise<boolean> {
        return this.isThumbnailChecked(BLUR_THUMBNAIL);
    }

    /**
     * Clicks OK to apply the selected background and close the dialog.
     */
    confirm(): Promise<void> {
        return this.clickOkButton();
    }

    /**
     * Clicks the X button to cancel without applying any changes.
     */
    cancel(): Promise<void> {
        return this.clickCloseButton();
    }
}