using System.Net;

using static System.Net.Mime.MediaTypeNames;

namespace NpgsqlRest;

public static class NpgsqlRestMiddlewareExtensions

{

public static IApplicationBuilder UseNpgsqlRest(this IApplicationBuilder builder, NpgsqlRestOptions options)

{

if (options.ConnectionString is null && options.DataSource is null && options.ServiceProviderMode == ServiceProviderObject.None)

{

throw new ArgumentException("ConnectionString and DataSource are null and ServiceProviderMode is set to None. You must specify connection with connection string, DataSource object or with ServiceProvider");

}

if (options.ConnectionString is not null && options.DataSource is not null && options.ServiceProviderMode == ServiceProviderObject.None)

{

throw new ArgumentException("Both ConnectionString and DataSource are provided. Please specify only one.");

}

if (options.Logger is not null)

{

NpgsqlRestMiddleware.SetLogger(options.Logger);

}

else if (builder is WebApplication app)

{

var factory = app.Services.GetRequiredService<ILoggerFactory>();

NpgsqlRestMiddleware.SetLogger(factory is not null ? factory.CreateLogger(options.LoggerName ?? typeof(NpgsqlRestMiddlewareExtensions).Namespace ?? "NpgsqlRest") : app.Logger);

}

NpgsqlRestMiddleware.SetMetadata(NpgsqlRestMetadataBuilder.Build(options, NpgsqlRestMiddleware.Logger, builder));

if (NpgsqlRestMiddleware.Metadata.Entries.Count == 0)

{

return builder;

}

NpgsqlRestMiddleware.SetOptions(options);

NpgsqlRestMiddleware.SetServiceProvider(builder.ApplicationServices);

bool streamingEventsItialized = false;

if (NpgsqlRestMiddleware.metadata.HasStreamingEvents is true)

{

builder.UseMiddleware<NpgsqlRestNoticeEventSource>();

streamingEventsItialized = true;

}

if (options.RefreshEndpointEnabled)

{

var refreshMethodUpper = options.RefreshMethod.ToUpperInvariant();

var refreshPathUpper = options.RefreshPath.ToUpperInvariant();

builder.Use(async (context, next) =>

{

if (context.Request.Method.Equals(refreshMethodUpper, StringComparison.OrdinalIgnoreCase) &&

context.Request.Path.Equals(refreshPathUpper, StringComparison.OrdinalIgnoreCase))

{

try

{

Volatile.Write(ref NpgsqlRestMiddleware.metadata, NpgsqlRestMetadataBuilder.Build(options, options.Logger, builder));

NpgsqlRestMiddleware.lookup = NpgsqlRestMiddleware.metadata.Entries.GetAlternateLookup<ReadOnlySpan<char>>();

context.Response.StatusCode = (int)HttpStatusCode.OK;

await context.Response.CompleteAsync();

if (NpgsqlRestMiddleware.metadata.HasStreamingEvents is true && streamingEventsItialized is false)

{

builder.UseMiddleware<NpgsqlRestNoticeEventSource>();

streamingEventsItialized = true;

}

}

catch (Exception e)

{

options.Logger?.LogError(e, "Failed to refresh metadata");

context.Response.StatusCode = (int)HttpStatusCode.InternalServerError;

context.Response.ContentType = Text.Plain;

await context.Response.WriteAsync($"Failed to refresh metadata: {e.Message}");

await context.Response.CompleteAsync();

}

return;

}

await next(context);

});

}

return builder.UseMiddleware<NpgsqlRestMiddleware>();

}

}