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

/// <summary>
/// Tests for parsing the configured SMTP TLS mode into the three-state enum.
/// </summary>
public class SmtpTlsModeParserTests
{
    /// <summary>Verifies that a known mode string parses to the expected TLS mode.</summary>
    /// <param name="input">The configured mode string.</param>
    /// <param name="expected">The expected parsed TLS mode.</param>
    [Theory]
    [InlineData("none", SmtpTlsMode.None)]
    [InlineData("None", SmtpTlsMode.None)]
    [InlineData("NONE", SmtpTlsMode.None)]
    [InlineData("starttls", SmtpTlsMode.StartTls)]
    [InlineData("StartTLS", SmtpTlsMode.StartTls)]
    [InlineData("ssl", SmtpTlsMode.Ssl)]
    [InlineData("SSL", SmtpTlsMode.Ssl)]
    [InlineData("  starttls  ", SmtpTlsMode.StartTls)]
    public void Parse_KnownModes_ReturnsExpected(string input, SmtpTlsMode expected)
    {
        Assert.Equal(expected, SmtpTlsModeParser.Parse(input));
    }

    /// <summary>Verifies that a null or empty mode defaults to StartTLS.</summary>
    /// <param name="input">The null or empty mode string.</param>
    [Theory]
    [InlineData(null)]
    [InlineData("")]
    [InlineData("   ")]
    public void Parse_NullOrEmpty_DefaultsToStartTls(string? input)
    {
        Assert.Equal(SmtpTlsMode.StartTls, SmtpTlsModeParser.Parse(input));
    }

    /// <summary>Verifies that an unknown mode string throws.</summary>
    /// <param name="input">The unrecognized mode string.</param>
    [Theory]
    [InlineData("auto")]
    [InlineData("tls")]
    [InlineData("implicit")]
    public void Parse_UnknownMode_Throws(string input)
    {
        // An unknown mode must be rejected, not silently treated as Auto.
        Assert.Throws<ArgumentException>(() => SmtpTlsModeParser.Parse(input));
    }
}