using SQLInsight.Core.Data;

namespace SQLInsight.Collectors.Instance;

public sealed class ConfigurationCollector : Collector<ConfigurationSnapshot>
{
    internal const string Sql2005 =
        "SELECT name, CAST(value AS bigint), CAST(value_in_use AS bigint) FROM sys.configurations";

    // What sp_configure itself reads on SQL Server 2000.
    internal const string Sql2000 = """
        SELECT v.name, CAST(c.value AS bigint), CAST(r.value AS bigint)
        FROM master.dbo.spt_values v
        JOIN master.dbo.sysconfigures c ON c.config = v.number
        JOIN master.dbo.syscurconfigs r ON r.config = v.number
        WHERE v.type = 'C'
        """;

    public override string Name => "configuration";
    public override TimeSpan DefaultInterval => TimeSpan.FromMinutes(15);

    protected override async Task<ConfigurationSnapshot> CollectAsync(CollectorContext context, ConfigurationSnapshot? previous)
    {
        var sql = context.Instance.Version.Major >= 9 ? Sql2005 : Sql2000;
        var options = await Db.QueryAsync(context.Connection, sql, r => new ConfigurationOption(r.String(0), r.Long(1), r.Long(2)), context.CancellationToken)
            .ConfigureAwait(false);
        return new ConfigurationSnapshot { CapturedAt = context.Now, Options = options };
    }
}