using Microsoft.Playwright;

namespace ZB.MOM.WW.ScadaBridge.CentralUI.PlaywrightTests.Deployment;

/// <summary>
/// Shared Topology-page navigation for the Playwright suites. The page loads lazily
/// (bounded instance pages per branch, behind explicit "Load instances" loaders), so
/// any test that addresses an area or instance row must first expand and load every
/// branch.
/// </summary>
internal static class TopologyPageHelper
{
    /// <summary>
    /// Navigates to the Topology page and returns a page whose tree is stable and
    /// fully expanded: it unchecks the <c>#live-updates</c> switch (stopping the 15s
    /// timer that would otherwise reload the tree and collapse expansions / tear down
    /// open dialogs and rename inputs), then clicks <c>Expand all areas</c> so nested
    /// area nodes are rendered and locatable.
    /// </summary>
    /// <param name="pw">The Playwright fixture used to open an authenticated page.</param>
    /// <returns>The authenticated page showing the fully-loaded Topology tree.</returns>
    public static async Task<IPage> OpenStableTopologyAsync(PlaywrightFixture pw) =>
        await OpenStableTopologyAsync(await pw.NewAuthenticatedPageAsync());

    /// <summary>Navigates an existing authenticated <paramref name="page"/> to the fully-loaded Topology tree.</summary>
    /// <param name="page">An authenticated page.</param>
    /// <returns>The same page, showing the fully-loaded Topology tree.</returns>
    public static async Task<IPage> OpenStableTopologyAsync(IPage page)
    {
        await page.GotoAsync($"{PlaywrightFixture.BaseUrl}/deployment/topology");
        await page.WaitForLoadStateAsync(LoadState.NetworkIdle);
        var live = page.Locator("#live-updates");
        if (await live.IsCheckedAsync()) await live.UncheckAsync();   // stop the 15s tree reload
        // Lazy topology loads a bounded first page per branch. These small authoring
        // fixtures need their sites/areas loaded before addressing labels or instances.
        // "Expand all" re-renders over the SignalR circuit, so the click returns before the
        // newly-expanded branches (and their "Load instances" loaders) exist. Wait until no
        // collapsed branch remains before counting loaders — counting immediately raced the
        // render and returned an unexpanded tree whenever the round-trip lost.
        var collapsed = page.Locator("li[role='treeitem'][aria-expanded='false']");
        for (var branch = 0; branch < 300; branch++)
        {
            await page.Locator("button[aria-label='Expand all areas']").ClickAsync();
            await Assertions.Expect(collapsed).ToHaveCountAsync(0);
            var load = page.GetByRole(AriaRole.Button, new() { Name = "Load instances", Exact = true });
            if (await load.CountAsync() == 0) return page;
            var pages = page.GetByText("Page 1", new() { Exact = true });
            var count = await pages.CountAsync();
            await load.First.ClickAsync();
            await Assertions.Expect(pages).ToHaveCountAsync(count + 1);
        }
        throw new InvalidOperationException("Topology fixture exceeded 300 branches.");
    }
}