namespace ZB.MOM.WW.ScadaBridge.NotificationService.Tests;

/// <summary>
/// Tests for scrubbing SMTP credential secrets out of log/result text.
/// </summary>
public class CredentialRedactorTests
{
    /// <summary>Verifies that a Basic auth password is masked.</summary>
    [Fact]
    public void Scrub_BasicAuthPassword_IsMasked()
    {
        // Password 'Hunter2pass!word' is 16 chars (>= MinSecretLength=12) and
        // therefore qualifies as a redactable secret-shaped trailing component.
        var text = "535 5.7.8 Authentication failed for user 'svc' with password 'Hunter2pass!word'";
        var result = CredentialRedactor.Scrub(text, "svc:Hunter2pass!word");

        Assert.DoesNotContain("Hunter2pass!word", result);
        Assert.DoesNotContain("svc:Hunter2pass!word", result);
    }

    /// <summary>Verifies that an OAuth2 client secret is masked.</summary>
    [Fact]
    public void Scrub_OAuth2ClientSecret_IsMasked()
    {
        var text = "Token request failed: client_secret=Sup3rSecretValue rejected by tenant";
        var result = CredentialRedactor.Scrub(text, "tenant-guid:client-guid:Sup3rSecretValue");

        Assert.DoesNotContain("Sup3rSecretValue", result);
    }

    /// <summary>Verifies that null credentials leave the text unchanged.</summary>
    [Fact]
    public void Scrub_NullCredentials_ReturnsTextUnchanged()
    {
        Assert.Equal("plain text", CredentialRedactor.Scrub("plain text", null));
    }

    /// <summary>Verifies that scrubbing null text returns an empty string.</summary>
    [Fact]
    public void Scrub_NullText_ReturnsEmpty()
    {
        Assert.Equal(string.Empty, CredentialRedactor.Scrub(null, "user:pass"));
    }

    // --- Don't over-mask short non-secret components ---

    /// <summary>Verifies that a short user name is not masked outside the packed credential string.</summary>
    [Fact]
    public void Scrub_ShortUserName_IsNotMaskedOutsidePackedString()
    {
        // 'root' is the Basic Auth user name — short, common, and absolutely
        // not a secret. It must NOT be masked when it appears in unrelated
        // diagnostic text like a file path.
        var text = "Config file at /root/.config/scada.conf was not found.";
        var result = CredentialRedactor.Scrub(text, "root:hunter2longenoughpwd");

        Assert.Contains("/root/.config", result);
    }

    /// <summary>Verifies that a tenant ID is not masked outside the packed credential string.</summary>
    [Fact]
    public void Scrub_TenantId_IsNotMaskedOutsidePackedString()
    {
        // The tenant id is not secret — only the client secret is. A tenant id
        // appearing in unrelated text (e.g. an error-code suffix) must survive.
        var text = "Error code tnt-1234567890-abcd reported by upstream";
        var result = CredentialRedactor.Scrub(text, "tnt-1234567890-abcd:cli-guid:RealClientSecretLongEnough");

        Assert.Contains("tnt-1234567890-abcd", result);
    }

    /// <summary>Verifies that a full packed credential is always masked regardless of its length.</summary>
    [Fact]
    public void Scrub_FullPackedCredential_IsAlwaysMaskedRegardlessOfLength()
    {
        // Even a short packed string must be masked when it appears verbatim —
        // that exact appearance can only come from the credential itself.
        var text = "Auth bundle was rejected: u:p";
        var result = CredentialRedactor.Scrub(text, "u:p");

        Assert.DoesNotContain("u:p", result);
    }
}