lmxopcua/tests/Drivers/ZB.MOM.WW.OtOpcUa.Driver.Sql.Tests/ColonMarkerDialect.cs

using System.Data.Common;
using ZB.MOM.WW.OtOpcUa.Core.Abstractions;
using ZB.MOM.WW.OtOpcUa.Driver.Sql.Contracts;

namespace ZB.MOM.WW.OtOpcUa.Driver.Sql.Tests;

/// <summary>
///     A <b>test-only</b> dialect that spells parameters the ODP.NET way — <c>:name</c> in the SQL text and a
///     <b>bare</b> <c>name</c> as the <see cref="DbParameter.ParameterName"/> — over the SQLite fixture. It is
///     the falsifiability control for dialect-owned parameter naming: every marker in this repo was hardcoded
///     <c>"@"</c> before, and a planner or loader that still hardcodes it emits <c>@k0</c> against this
///     dialect and fails loudly.
///     <para><b>Why the two halves must differ.</b> A dialect whose marker and bind name are the same string
///     (SQL Server, Npgsql, SQLite) cannot tell a call site that <em>copies</em> the plan's bind name apart
///     from one that reuses the marker. Oracle is the provider where they genuinely diverge, so this fake
///     reproduces that divergence rather than merely changing the prefix.</para>
///     <para><b>It really executes.</b> Everything but the parameter naming (and the catalog SQL's markers)
///     delegates to <see cref="SqliteDialect"/>, and Microsoft.Data.Sqlite accepts both a <c>:</c>-prefixed
///     marker and a prefix-less parameter name — so a poll or a catalog load driven through this dialect runs
///     against the real fixture database rather than being asserted on as text.</para>
///     <para>A decorator rather than a subclass: <see cref="SqliteDialect"/> is sealed, and
///     <c>new</c>-hiding a member would leave interface dispatch calling the original — the substitution
///     would silently not happen and the control would pass for the wrong reason.</para>
/// </summary>
public sealed class ColonMarkerDialect : ISqlDialect
{
    private static readonly SqliteDialect Inner = new();

    /// <summary>Every command handed to <see cref="ConfigureCommand"/>, kept so its binds can be read back.</summary>
    private readonly List<DbCommand> _commands = [];

    /// <summary>How many times <see cref="ConfigureCommand"/> has been called on this instance.</summary>
    /// <remarks>
    ///     Oracle's <c>BindByName</c> is set here, and a command created without it mis-binds by position
    ///     rather than failing — so "was every command configured" has to be observable to be testable.
    /// </remarks>
    public int ConfiguredCommands
    {
        get { lock (_commands) return _commands.Count; }
    }

    /// <summary>
    ///     The <see cref="DbParameter.ParameterName"/> of every parameter bound on every configured command,
    ///     read after the fact.
    ///     <para><b>Why this and not the query's own success.</b> Microsoft.Data.Sqlite resolves a parameter
    ///     whether it is named <c>:k0</c> or bare <c>k0</c>, so a poll that returns the right values proves
    ///     the SQL parsed — not that the caller bound the dialect's bind name. Only the name actually put on
    ///     the parameter distinguishes the two, and on ODP.NET the wrong one is a hard bind failure.</para>
    /// </summary>
    public IReadOnlyList<string> BoundParameterNames
    {
        get
        {
            lock (_commands)
                return _commands
                    .SelectMany(c => c.Parameters.Cast<DbParameter>())
                    .Select(p => p.ParameterName)
                    .ToList();
        }
    }

    /// <inheritdoc/>
    public SqlProvider Provider => Inner.Provider;

    /// <inheritdoc/>
    public DbProviderFactory Factory => Inner.Factory;

    /// <inheritdoc/>
    public string LivenessSql => Inner.LivenessSql;

    /// <inheritdoc/>
    public string SingleRowLimitPrefix => Inner.SingleRowLimitPrefix;

    /// <inheritdoc/>
    public string SingleRowLimitSuffix => Inner.SingleRowLimitSuffix;

    /// <inheritdoc/>
    public string ListSchemasSql => Colonize(Inner.ListSchemasSql);

    /// <inheritdoc/>
    public string DefaultSchemaSql => Colonize(Inner.DefaultSchemaSql);

    /// <inheritdoc/>
    public string ListTablesSql => Colonize(Inner.ListTablesSql);

    /// <inheritdoc/>
    public string ListColumnsSql => Colonize(Inner.ListColumnsSql);

    /// <inheritdoc/>
    public string ParameterMarker(string baseName) => ":" + baseName;

    /// <summary>The bare name, with no prefix — ODP.NET's convention, and deliberately NOT the marker.</summary>
    /// <param name="baseName">The planner's/loader's base name.</param>
    /// <returns>The bind name.</returns>
    public string ParameterBindName(string baseName) => baseName;

    /// <inheritdoc/>
    public void ConfigureCommand(DbCommand command)
    {
        ArgumentNullException.ThrowIfNull(command);
        lock (_commands) _commands.Add(command);
    }

    /// <inheritdoc/>
    public string QuoteIdentifier(string ident) => Inner.QuoteIdentifier(ident);

    /// <inheritdoc/>
    public DriverDataType MapColumnType(string sqlDataType) => Inner.MapColumnType(sqlDataType);

    /// <summary>
    ///     Rewrites the SQLite dialect's <c>@</c> markers as <c>:</c> markers. The catalog SQL is dialect-owned
    ///     text, so a colon-marker dialect must carry colon markers in it — that is precisely the coupling the
    ///     catalog loader's bind names have to stay in step with.
    /// </summary>
    private static string Colonize(string sql) => sql.Replace('@', ':');
}