using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.AdminUI.Uns.TagEditors;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;

namespace ZB.MOM.WW.OtOpcUa.AdminUI.Tests.Uns;

/// <summary>
///     Parity guards for the per-driver <b>CSV column</b> dispatch map (<c>deferment.md</c> G-5). It was
///     already a testable structure — unlike the two Razor <c>@switch</c> blocks that needed extracting
///     first — so nothing but the tests was missing.
/// </summary>
/// <remarks>
///     <b>The browse-commit seam (G-6) is guarded next door, not here (Gitea #558).</b> This class used to
///     also hold <c>Browse_commit_falls_back_to_the_generic_address_key_for_exactly_the_non_browsable_drivers</c>,
///     over the same <c>RawBrowseCommitMapper.BuildTagConfig</c> seam
///     <see cref="RawBrowseCommitMapperParityTests"/> now enumerates. Two guards over one seam means two
///     hand-authored lists of "drivers that legitimately reach the generic key", and the pair can only
///     drift — this one's was additionally MISNAMED (<c>NonBrowsableDriverTypes</c> really meant "types
///     that produce the generic key": <c>AbLegacy</c> is genuinely non-browsable yet correctly absent,
///     because it has a typed branch). The surviving list is
///     <c>RawBrowseCommitMapperParityTests.GenericKeyExemptions</c>, which is named for what it holds,
///     carries a written reason per entry, and is checked against a <b>derived</b> browsable set rather
///     than a second hand-authored one.
/// </remarks>
[Trait("Category", "Unit")]
public sealed class DriverDispatchMapParityTests
{
    /// <summary>
    ///     Driver types with a typed tag editor but no CSV map, so import/export silently degrades them to
    ///     the raw <c>TagConfigJson</c> fallback. Empty — every editor-backed driver now has typed columns.
    ///     <para>Deliberately expressed as "has a typed editor ⇒ has typed CSV columns" rather than
    ///     "every driver type", because a driver with no typed editor has nothing to project into columns.
    ///     Tying the two maps together is what makes this catch the next omission.</para>
    /// </summary>
    [Fact]
    public void Every_driver_with_a_typed_tag_editor_has_typed_csv_columns()
    {
        var missing = DriverTypeNames.All
            .Where(t => TagConfigEditorMap.Resolve(t) is not null && CsvColumnMap.Resolve(t) is null)
            .OrderBy(t => t, StringComparer.Ordinal)
            .ToList();

        missing.ShouldBeEmpty(
            $"these driver types have a typed tag editor but no CsvColumnMap entry, so CSV import/export "
            + $"drops them to the raw TagConfigJson fallback: {string.Join(", ", missing)}");
    }

    /// <summary>A CSV map for a driver type that no longer exists is a stale entry.</summary>
    [Fact]
    public void Every_csv_map_targets_a_declared_driver_type()
    {
        var declared = DriverTypeNames.All.ToHashSet(StringComparer.OrdinalIgnoreCase);
        var stale = CsvColumnMap.All
            .Select(m => m.DriverType)
            .Where(t => !declared.Contains(t))
            .OrderBy(t => t, StringComparer.Ordinal)
            .ToList();

        stale.ShouldBeEmpty($"CsvColumnMap has entries for undeclared driver types: {string.Join(", ", stale)}");
    }
}