import {strict as assert} from "assert";

import type {ElementHandle, Page} from "puppeteer";

import common from "../puppeteer_lib/common";

async function user_checkbox(page: Page, name: string): Promise<string> {
    const user_id = await common.get_user_id_from_name(page, name);
    return `#user-checkboxes [data-user-id="${CSS.escape(user_id.toString())}"]`;
}

async function user_span(page: Page, name: string): Promise<string> {
    return (await user_checkbox(page, name)) + " input ~ span";
}

async function stream_checkbox(page: Page, stream_name: string): Promise<string> {
    const stream_id = await common.get_stream_id(page, stream_name);
    return `#stream-checkboxes [data-stream-id="${CSS.escape(stream_id.toString())}"]`;
}

async function stream_span(page: Page, stream_name: string): Promise<string> {
    return (await stream_checkbox(page, stream_name)) + " input ~ span";
}

async function wait_for_checked(page: Page, user_name: string, is_checked: boolean): Promise<void> {
    const selector = await user_checkbox(page, user_name);
    await page.waitForFunction(
        (selector: string, is_checked: boolean) =>
            $(selector).find("input")[0].checked === is_checked,
        {},
        selector,
        is_checked,
    );
}

async function stream_name_error(page: Page): Promise<string> {
    await page.waitForSelector("#stream_name_error", {visible: true});
    return await common.get_text_from_selector(page, "#stream_name_error");
}

async function open_streams_modal(page: Page): Promise<void> {
    const all_streams_selector = 'a[href="#streams/all"]';
    await page.waitForSelector(all_streams_selector, {visible: true});
    await page.click(all_streams_selector);

    await page.waitForSelector("#subscription_overlay.new-style", {visible: true});
    const url = await common.page_url_with_fragment(page);
    assert(url.includes("#streams/all"));
}

async function test_subscription_button_verona_stream(page: Page): Promise<void> {
    const button_selector = "[data-stream-name='Verona'] .sub_unsub_button";
    const subscribed_selector = `${button_selector}.checked`;
    const unsubscribed_selector = `${button_selector}:not(.checked)`;

    async function subscribed(): Promise<ElementHandle | null> {
        return await page.waitForSelector(subscribed_selector, {visible: true});
    }

    async function unsubscribed(): Promise<ElementHandle | null> {
        return await page.waitForSelector(unsubscribed_selector, {visible: true});
    }

    // Note that we intentionally re-find the button after each click, since
    // the live-update code may replace the whole row.
    let button;

    // We assume Verona is already subscribed, so the first line here
    // should happen immediately.
    button = await subscribed();
    button!.click();
    button = await unsubscribed();
    button!.click();
    button = await subscribed();
    button!.click();
    button = await unsubscribed();
    button!.click();
    button = await subscribed();
}

async function click_create_new_stream(
    page: Page,
    cordelia_checkbox: string,
    othello_checkbox: string,
): Promise<void> {
    await page.click("#add_new_subscription .create_stream_button");
    await page.waitForSelector(cordelia_checkbox, {visible: true});
    await page.waitForSelector(othello_checkbox, {visible: true});
}

async function open_copy_from_stream_dropdown(
    page: Page,
    scotland_checkbox: string,
    rome_checkbox: string,
): Promise<void> {
    await page.click("#copy-from-stream-expand-collapse .control-label");
    await page.waitForSelector(scotland_checkbox, {visible: true});
    await page.waitForSelector(rome_checkbox, {visible: true});
}

async function test_check_all_only_affects_visible_users(page: Page): Promise<void> {
    await page.click(".subs_set_all_users");
    await wait_for_checked(page, "cordelia", false);
    await wait_for_checked(page, "othello", true);
}

async function test_uncheck_all(page: Page): Promise<void> {
    await page.click(".subs_unset_all_users");
    await wait_for_checked(page, "othello", false);
}

async function clear_ot_filter_with_backspace(page: Page): Promise<void> {
    await page.click(".add-user-list-filter");
    await page.keyboard.press("Backspace");
    await page.keyboard.press("Backspace");
}

async function verify_filtered_users_are_visible_again(
    page: Page,
    cordelia_checkbox: string,
    othello_checkbox: string,
): Promise<void> {
    await page.waitForSelector(cordelia_checkbox, {visible: true});
    await page.waitForSelector(othello_checkbox, {visible: true});
}

async function test_user_filter_ui(
    page: Page,
    cordelia_checkbox: string,
    othello_checkbox: string,
    scotland_checkbox: string,
    rome_checkbox: string,
): Promise<void> {
    await page.waitForSelector("form#stream_creation_form", {visible: true});

    await common.fill_form(page, "form#stream_creation_form", {user_list_filter: "ot"});
    await page.waitForSelector("#user-checkboxes", {visible: true});
    await page.waitForSelector(cordelia_checkbox, {hidden: true});
    await page.waitForSelector(othello_checkbox, {visible: true});

    // Filter shouldn't affect streams.
    await page.waitForSelector(scotland_checkbox, {visible: true});
    await page.waitForSelector(rome_checkbox, {visible: true});

    await test_check_all_only_affects_visible_users(page);
    await test_uncheck_all(page);

    await clear_ot_filter_with_backspace(page);
    await verify_filtered_users_are_visible_again(page, cordelia_checkbox, othello_checkbox);
}

async function create_stream(page: Page): Promise<void> {
    await page.waitForXPath('//*[text()="Create stream"]', {visible: true});
    await common.fill_form(page, "form#stream_creation_form", {
        stream_name: "Puppeteer",
        stream_description: "Everything Puppeteer",
    });
    await page.click(await stream_span(page, "Scotland")); //  Subscribes all users from Scotland
    await page.click(await user_span(page, "cordelia")); // Add cordelia.
    await wait_for_checked(page, "cordelia", true);
    await page.click(await user_span(page, "othello")); // Remove othello who was selected from Scotland.
    await wait_for_checked(page, "othello", false);
    await page.click("form#stream_creation_form button.button.sea-green");
    await page.waitForFunction(() => $(".stream-name").is(':contains("Puppeteer")'));
    const stream_name = await common.get_text_from_selector(
        page,
        ".stream-header .stream-name .stream-name-editable",
    );
    const stream_description = await common.get_text_from_selector(
        page,
        ".stream-description-editable ",
    );
    const subscriber_count_selector = "[data-stream-name='Puppeteer'] .subscriber-count";
    assert.strictEqual(stream_name, "Puppeteer");
    assert.strictEqual(stream_description, "Everything Puppeteer");

    // Assert subscriber count becomes 6(scotland(+5), cordelia(+1), othello(-1), Desdemona(+1)).
    await page.waitForFunction(
        (subscriber_count_selector: string) => $(subscriber_count_selector).text().trim() === "6",
        {},
        subscriber_count_selector,
    );
}

async function test_streams_with_empty_names_cannot_be_created(page: Page): Promise<void> {
    await page.click("#add_new_subscription .create_stream_button");
    await page.waitForSelector("form#stream_creation_form", {visible: true});
    await common.fill_form(page, "form#stream_creation_form", {stream_name: "  "});
    await page.click("form#stream_creation_form button.button.sea-green");
    assert.strictEqual(await stream_name_error(page), "A stream needs to have a name");
}

async function test_streams_with_duplicate_names_cannot_be_created(page: Page): Promise<void> {
    await common.fill_form(page, "form#stream_creation_form", {stream_name: "Puppeteer"});
    await page.click("form#stream_creation_form button.button.sea-green");
    assert.strictEqual(await stream_name_error(page), "A stream with this name already exists");

    const cancel_button_selector = "form#stream_creation_form button.button.white";
    await page.click(cancel_button_selector);
}

async function test_stream_creation(page: Page): Promise<void> {
    const cordelia_checkbox = await user_checkbox(page, "cordelia");
    const othello_checkbox = await user_checkbox(page, "othello");
    const scotland_checkbox = await stream_checkbox(page, "Scotland");
    const rome_checkbox = await stream_checkbox(page, "Rome");

    await click_create_new_stream(page, cordelia_checkbox, othello_checkbox);
    await open_copy_from_stream_dropdown(page, scotland_checkbox, rome_checkbox);
    await test_user_filter_ui(
        page,
        cordelia_checkbox,
        othello_checkbox,
        scotland_checkbox,
        rome_checkbox,
    );
    await create_stream(page);
    await test_streams_with_empty_names_cannot_be_created(page);
    await test_streams_with_duplicate_names_cannot_be_created(page);
}

async function test_streams_search_feature(page: Page): Promise<void> {
    assert.strictEqual(await common.get_text_from_selector(page, "#search_stream_name"), "");
    const hidden_streams_selector = ".stream-row.notdisplayed .stream-name";
    assert.strictEqual(
        await common.get_text_from_selector(
            page,
            '.stream-row[data-stream-name="Verona"] .stream-name',
        ),
        "Verona",
    );
    assert(
        !(await common.get_text_from_selector(page, hidden_streams_selector)).includes("Verona"),
        "#Verona is hidden",
    );

    await page.type('#stream_filter input[type="text"]', "Puppeteer");
    assert.strictEqual(
        await common.get_text_from_selector(page, ".stream-row:not(.notdisplayed) .stream-name"),
        "Puppeteer",
    );
    assert(
        (await common.get_text_from_selector(page, hidden_streams_selector)).includes("Verona"),
        "#Verona is not hidden",
    );
    assert(
        !(await common.get_text_from_selector(page, hidden_streams_selector)).includes("Puppeteer"),
        "Puppeteer is hidden after searching.",
    );
}

async function subscriptions_tests(page: Page): Promise<void> {
    await common.log_in(page);
    await open_streams_modal(page);
    await test_subscription_button_verona_stream(page);
    await test_stream_creation(page);
    await test_streams_search_feature(page);
    await common.log_out(page);
}

common.run_test(subscriptions_tests);