using System;
using Shouldly;
using Xunit;
using ZB.MOM.WW.LmxOpcUa.Host.Domain;
using ZB.MOM.WW.LmxOpcUa.Host.OpcUa;

namespace ZB.MOM.WW.LmxOpcUa.Tests.OpcUa
{
    /// <summary>
    /// Verifies how bridge VTQ values are translated to and from OPC UA data values for the published namespace.
    /// </summary>
    public class DataValueConverterTests
    {
        /// <summary>
        /// Confirms that boolean runtime values are preserved when converted to OPC UA data values.
        /// </summary>
        [Fact]
        public void FromVtq_Boolean()
        {
            var vtq = Vtq.Good(true);
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe(true);
            Opc.Ua.StatusCode.IsGood(dv.StatusCode).ShouldBe(true);
        }

        /// <summary>
        /// Confirms that integer runtime values are preserved when converted to OPC UA data values.
        /// </summary>
        [Fact]
        public void FromVtq_Int32()
        {
            var vtq = Vtq.Good(42);
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe(42);
        }

        /// <summary>
        /// Confirms that float runtime values are preserved when converted to OPC UA data values.
        /// </summary>
        [Fact]
        public void FromVtq_Float()
        {
            var vtq = Vtq.Good(3.14f);
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe(3.14f);
        }

        /// <summary>
        /// Confirms that double runtime values are preserved when converted to OPC UA data values.
        /// </summary>
        [Fact]
        public void FromVtq_Double()
        {
            var vtq = Vtq.Good(3.14159);
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe(3.14159);
        }

        /// <summary>
        /// Confirms that string runtime values are preserved when converted to OPC UA data values.
        /// </summary>
        [Fact]
        public void FromVtq_String()
        {
            var vtq = Vtq.Good("hello");
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe("hello");
        }

        /// <summary>
        /// Confirms that UTC timestamps remain UTC when a VTQ is converted for OPC UA clients.
        /// </summary>
        [Fact]
        public void FromVtq_DateTime_IsUtc()
        {
            var utcTime = new DateTime(2024, 6, 15, 10, 30, 0, DateTimeKind.Utc);
            var vtq = new Vtq(utcTime, utcTime, Quality.Good);
            var dv = DataValueConverter.FromVtq(vtq);
            ((DateTime)dv.Value).Kind.ShouldBe(DateTimeKind.Utc);
        }

        /// <summary>
        /// Confirms that elapsed-time values are exposed to OPC UA clients in seconds.
        /// </summary>
        [Fact]
        public void FromVtq_TimeSpan_ConvertedToSeconds()
        {
            var vtq = Vtq.Good(TimeSpan.FromMinutes(2.5));
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe(150.0);
        }

        /// <summary>
        /// Confirms that string arrays remain arrays when exposed through OPC UA.
        /// </summary>
        [Fact]
        public void FromVtq_StringArray()
        {
            var arr = new[] { "a", "b", "c" };
            var vtq = Vtq.Good(arr);
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe(arr);
        }

        /// <summary>
        /// Confirms that integer arrays remain arrays when exposed through OPC UA.
        /// </summary>
        [Fact]
        public void FromVtq_IntArray()
        {
            var arr = new[] { 1, 2, 3 };
            var vtq = Vtq.Good(arr);
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBe(arr);
        }

        /// <summary>
        /// Confirms that bad runtime quality is translated to a bad OPC UA status code.
        /// </summary>
        [Fact]
        public void FromVtq_BadQuality_MapsToStatusCode()
        {
            var vtq = Vtq.Bad(Quality.BadCommFailure);
            var dv = DataValueConverter.FromVtq(vtq);
            Opc.Ua.StatusCode.IsBad(dv.StatusCode).ShouldBe(true);
        }

        /// <summary>
        /// Confirms that uncertain runtime quality is translated to an uncertain OPC UA status code.
        /// </summary>
        [Fact]
        public void FromVtq_UncertainQuality()
        {
            var vtq = Vtq.Uncertain(42);
            var dv = DataValueConverter.FromVtq(vtq);
            Opc.Ua.StatusCode.IsUncertain(dv.StatusCode).ShouldBe(true);
        }

        /// <summary>
        /// Confirms that null runtime values remain null when converted for OPC UA.
        /// </summary>
        [Fact]
        public void FromVtq_NullValue()
        {
            var vtq = Vtq.Good(null);
            var dv = DataValueConverter.FromVtq(vtq);
            dv.Value.ShouldBeNull();
        }

        /// <summary>
        /// Confirms that a data value can round-trip back into a VTQ without losing the process value or quality.
        /// </summary>
        [Fact]
        public void ToVtq_RoundTrip()
        {
            var original = new Vtq(42, DateTime.UtcNow, Quality.Good);
            var dv = DataValueConverter.FromVtq(original);
            var roundTrip = DataValueConverter.ToVtq(dv);

            roundTrip.Value.ShouldBe(42);
            roundTrip.Quality.ShouldBe(Quality.Good);
        }
    }
}