using Microsoft.Extensions.Configuration;
using Shouldly;
using Xunit;

namespace ZB.MOM.WW.OtOpcUa.Runtime.Tests.Historian;

/// <summary>
///     #603 + review R1 m3: the two "is this node's LocalDb replicated" predicates — permissive for table
///     registration (<see cref="LocalDbReplicationPolicy.CapturesChanges"/>), strict for the alarm drain gate
///     (<see cref="LocalDbReplicationPolicy.SharesRowsWithPeer"/>).
/// </summary>
public sealed class LocalDbReplicationPolicyTests
{
    private const string Peer = "LocalDb:Replication:PeerAddress";
    private const string Key = "LocalDb:Replication:ApiKey";
    private const string Port = "LocalDb:SyncListenPort";

    private static IConfiguration Config(params (string Key, string? Value)[] pairs) =>
        new ConfigurationBuilder()
            .AddInMemoryCollection(pairs.Select(p => new KeyValuePair<string, string?>(p.Key, p.Value)))
            .Build();

    /// <summary>Registration: PeerAddress OR ApiKey counts; the listen port alone and blank values do not.</summary>
    [Theory]
    [InlineData(Peer, "http://peer:9001", true)]
    [InlineData(Key, "k", true)]
    [InlineData(Port, "9001", false)]
    [InlineData(Key, "  ", false)]
    public void CapturesChanges_follows_the_PeerAddress_or_ApiKey_rule(string key, string value, bool expected)
    {
        LocalDbReplicationPolicy.CapturesChanges(Config((key, value))).ShouldBe(expected);
    }

    /// <summary>Drain gate: ApiKey AND (PeerAddress OR SyncListenPort &gt; 0).</summary>
    [Theory]
    [InlineData("http://peer:9001", "k", null, true)]   // dialling half of a pair
    [InlineData(null, "k", "9001", true)]               // listening half of a pair
    [InlineData("http://peer:9001", "k", "9001", true)] // both
    [InlineData(null, "k", null, false)]                // key, no path: shares nothing (review R1 m3)
    [InlineData(null, "k", "0", false)]                 // port 0 = no listener
    [InlineData(null, "k", "nope", false)]              // unparseable port = no listener
    [InlineData("http://peer:9001", null, "9001", false)] // paths, no key: both auth directions fail closed
    [InlineData(null, "  ", "9001", false)]             // blank key
    public void SharesRowsWithPeer_needs_a_key_and_a_sync_path(string? peer, string? key, string? port, bool expected)
    {
        LocalDbReplicationPolicy.SharesRowsWithPeer(Config((Peer, peer), (Key, key), (Port, port))).ShouldBe(expected);
    }

    /// <summary>Every node the gate treats as sharing rows also captures — never a gated node with no capture.</summary>
    [Theory]
    [InlineData("http://peer:9001", "k", null)]
    [InlineData(null, "k", "9001")]
    public void A_node_sharing_rows_always_captures(string? peer, string? key, string? port)
    {
        var config = Config((Peer, peer), (Key, key), (Port, port));
        LocalDbReplicationPolicy.SharesRowsWithPeer(config).ShouldBeTrue();
        LocalDbReplicationPolicy.CapturesChanges(config).ShouldBeTrue();
    }

    /// <summary>No replication keys at all is an unpaired node under both predicates.</summary>
    [Fact]
    public void Both_predicates_are_false_for_an_empty_configuration()
    {
        LocalDbReplicationPolicy.CapturesChanges(Config()).ShouldBeFalse();
        LocalDbReplicationPolicy.SharesRowsWithPeer(Config()).ShouldBeFalse();
    }
}