using ZB.MOM.WW.Configuration;

namespace ZB.MOM.WW.ScadaBridge.SiteRuntime;

/// <summary>
/// Validates <see cref="SiteRuntimeOptions"/> at startup. These values size the
/// staggered Instance-Actor startup batches, the dedicated script-execution thread
/// pool, and the site-wide Akka stream's per-subscriber buffer; a zero or negative
/// count either creates a degenerate thread scheduler / stream stage or trips an
/// <see cref="ArgumentOutOfRangeException"/> deep inside actor construction with an
/// opaque message that never names the offending config key. Registered with
/// <c>ValidateOnStart()</c> so a bad <c>ScadaBridge:SiteRuntime</c> section fails
/// fast at boot with a clear, key-naming message.
/// </summary>
public sealed class SiteRuntimeOptionsValidator : OptionsValidatorBase<SiteRuntimeOptions>
{
    /// <inheritdoc />
    protected override void Validate(ValidationBuilder builder, SiteRuntimeOptions options)
    {
        builder.RequireThat(options.StartupBatchSize > 0,
            $"ScadaBridge:SiteRuntime:StartupBatchSize must be greater than 0 " +
            $"(was {options.StartupBatchSize}); it sizes each staggered Instance-Actor startup batch.");

        builder.RequireThat(options.StartupBatchDelayMs >= 0,
            $"ScadaBridge:SiteRuntime:StartupBatchDelayMs must be >= 0 " +
            $"(was {options.StartupBatchDelayMs}); it is the inter-batch startup delay.");

        builder.RequireThat(options.MaxScriptCallDepth > 0,
            $"ScadaBridge:SiteRuntime:MaxScriptCallDepth must be greater than 0 " +
            $"(was {options.MaxScriptCallDepth}); it bounds recursive CallScript/CallShared depth.");

        builder.RequireThat(options.ScriptExecutionTimeoutSeconds > 0,
            $"ScadaBridge:SiteRuntime:ScriptExecutionTimeoutSeconds must be greater than 0 " +
            $"(was {options.ScriptExecutionTimeoutSeconds}).");

        builder.RequireThat(options.StreamBufferSize > 0,
            $"ScadaBridge:SiteRuntime:StreamBufferSize must be greater than 0 " +
            $"(was {options.StreamBufferSize}); it is the per-subscriber site-stream buffer size.");

        builder.RequireThat(options.ScriptExecutionThreadCount > 0,
            $"ScadaBridge:SiteRuntime:ScriptExecutionThreadCount must be greater than 0 " +
            $"(was {options.ScriptExecutionThreadCount}); it sizes the dedicated script-execution scheduler.");

        builder.RequireThat(options.MirroredAlarmCapPerSource > 0,
            $"ScadaBridge:SiteRuntime:MirroredAlarmCapPerSource must be greater than 0 " +
            $"(was {options.MirroredAlarmCapPerSource}).");

        builder.RequireThat(options.NativeAlarmRetryIntervalMs > 0,
            $"ScadaBridge:SiteRuntime:NativeAlarmRetryIntervalMs must be greater than 0 " +
            $"(was {options.NativeAlarmRetryIntervalMs}).");

        builder.RequireThat(options.ConfigFetchTimeoutSeconds > 0,
            $"ScadaBridge:SiteRuntime:ConfigFetchTimeoutSeconds must be greater than 0 " +
            $"(was {options.ConfigFetchTimeoutSeconds}).");

        builder.RequireThat(options.ConfigFetchRetryCount >= 0,
            $"ScadaBridge:SiteRuntime:ConfigFetchRetryCount must be >= 0 " +
            $"(was {options.ConfigFetchRetryCount}).");

        builder.RequireThat(options.TagSubscribeRetryIntervalMs > 0,
            $"ScadaBridge:SiteRuntime:TagSubscribeRetryIntervalMs must be greater than 0 " +
            $"(was {options.TagSubscribeRetryIntervalMs}); a zero interval hot-loops the tag-subscribe " +
            "retry and a negative one throws inside the Instance Actor's retry scheduling.");

        builder.RequireThat(options.StuckScriptGraceMs >= 0,
            $"ScadaBridge:SiteRuntime:StuckScriptGraceMs must be >= 0 " +
            $"(was {options.StuckScriptGraceMs}); a negative grace throws inside the stuck-script watchdog's delay.");
    }
}