using System.IO;
using System.Reflection;
using Shouldly;
using Xunit;

namespace ZB.MOM.WW.OtOpcUa.Admin.Tests;

/// <summary>
///     Regression for Admin-010 — admin-ui.md "Tech Stack" requires Bootstrap 5
///     "vendored under wwwroot/lib/bootstrap/" so the Admin app has no third-party
///     runtime dependency and works in air-gapped fleet deployments. These tests
///     guard against a future re-introduction of the cdn.jsdelivr.net references
///     in App.razor.
/// </summary>
[Trait("Category", "Unit")]
public sealed class BootstrapVendoringTests
{
    [Fact]
    public void AppRazor_does_not_reference_a_remote_CDN_for_bootstrap()
    {
        var appRazor = File.ReadAllText(ResolveAdminPath("Components/App.razor"));

        appRazor.ShouldNotContain("cdn.jsdelivr.net",
            customMessage: "Admin-010: Bootstrap must be served from the vendored copy under wwwroot/lib/bootstrap/, not jsDelivr — air-gapped deployments cannot reach the public CDN.");
        appRazor.ShouldNotContain("cdnjs.cloudflare.com",
            customMessage: "Admin-010: third-party CDN references regress the vendoring requirement.");
        appRazor.ShouldNotContain("unpkg.com",
            customMessage: "Admin-010: third-party CDN references regress the vendoring requirement.");
    }

    [Fact]
    public void AppRazor_references_vendored_bootstrap_assets()
    {
        var appRazor = File.ReadAllText(ResolveAdminPath("Components/App.razor"));

        appRazor.ShouldContain("lib/bootstrap/css/bootstrap.min.css",
            customMessage: "App.razor must load the vendored Bootstrap stylesheet.");
        appRazor.ShouldContain("lib/bootstrap/js/bootstrap.bundle.min.js",
            customMessage: "App.razor must load the vendored Bootstrap JS bundle.");
    }

    [Fact]
    public void Vendored_bootstrap_assets_exist_under_wwwroot_lib_bootstrap()
    {
        var root = ResolveAdminPath("wwwroot/lib/bootstrap");

        Directory.Exists(root).ShouldBeTrue($"expected vendored bootstrap directory at '{root}'");
        File.Exists(Path.Combine(root, "css", "bootstrap.min.css")).ShouldBeTrue("bootstrap.min.css missing");
        File.Exists(Path.Combine(root, "js", "bootstrap.bundle.min.js")).ShouldBeTrue("bootstrap.bundle.min.js missing");

        // Sanity-check non-empty (a zero-byte placeholder would still pass File.Exists).
        new FileInfo(Path.Combine(root, "css", "bootstrap.min.css")).Length.ShouldBeGreaterThan(100_000);
        new FileInfo(Path.Combine(root, "js",  "bootstrap.bundle.min.js")).Length.ShouldBeGreaterThan(50_000);
    }

    /// <summary>Resolve a path under the Admin source project from the test runner's bin folder.</summary>
    private static string ResolveAdminPath(string relative)
    {
        var asmDir = Path.GetDirectoryName(typeof(BootstrapVendoringTests).Assembly.Location)!;
        // tests/Server/ZB.MOM.WW.OtOpcUa.Admin.Tests/bin/Debug/net10.0 -> ../../../../../src/Server/...
        var repoRoot = Path.GetFullPath(Path.Combine(asmDir, "..", "..", "..", "..", "..", ".."));
        return Path.Combine(repoRoot, "src", "Server", "ZB.MOM.WW.OtOpcUa.Admin", relative.Replace('/', Path.DirectorySeparatorChar));
    }
}