using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.Extensions.Hosting;
using StellaOps.Scheduler.Queue;
using StellaOps.Scheduler.WebService.GraphJobs.Events;
using StellaOps.Scheduler.WebService.Options;
using System;

namespace StellaOps.Scheduler.WebService.EventWebhooks;

internal static class WebhookRateLimiterServiceCollectionExtensions
{
    public static IServiceCollection AddSchedulerWebhookRateLimiter(
        this IServiceCollection services,
        IConfiguration configuration,
        IHostEnvironment environment)
    {
        ArgumentNullException.ThrowIfNull(services);
        ArgumentNullException.ThrowIfNull(configuration);
        ArgumentNullException.ThrowIfNull(environment);

        services.RemoveAll<IWebhookRateLimiter>();

        if (environment.IsEnvironment("Testing"))
        {
            services.AddSingleton<IWebhookRateLimiter, InMemoryWebhookRateLimiter>();
            return services;
        }

        var eventsOptions = new SchedulerEventsOptions();
        configuration.GetSection("Scheduler:Events").Bind(eventsOptions);
        eventsOptions.Webhooks ??= new SchedulerInboundWebhooksOptions();
        eventsOptions.Webhooks.Conselier ??= SchedulerWebhookOptions.CreateDefault("conselier");
        eventsOptions.Webhooks.Excitor ??= SchedulerWebhookOptions.CreateDefault("excitor");

        if (!eventsOptions.Webhooks.Conselier.Enabled && !eventsOptions.Webhooks.Excitor.Enabled)
        {
            services.AddSingleton<IWebhookRateLimiter, NoOpWebhookRateLimiter>();
            return services;
        }

        var queueOptions = new SchedulerQueueOptions();
        configuration.GetSection("scheduler:queue").Bind(queueOptions);

        if (queueOptions.Kind != SchedulerQueueTransportKind.Redis || string.IsNullOrWhiteSpace(queueOptions.Redis.ConnectionString))
        {
            throw new InvalidOperationException(
                "Scheduler inbound webhooks require scheduler:queue Redis connection outside the Testing environment.");
        }

        var redisOptions = new SchedulerRedisQueueOptions
        {
            ConnectionString = queueOptions.Redis.ConnectionString,
            Database = queueOptions.Redis.Database,
            InitializationTimeout = queueOptions.Redis.InitializationTimeout
        };

        services.AddSingleton<IWebhookRateLimiter>(sp =>
            new RedisWebhookRateLimiter(
                redisOptions,
                sp.GetRequiredService<IRedisConnectionFactory>(),
                sp.GetService<TimeProvider>()));

        return services;
    }
}