using System.Threading.Channels;
using Microsoft.EntityFrameworkCore;
using Novelly.Api.Agent;
using Novelly.Api.Beats;
using Novelly.Api.Chapters;
using Novelly.Api.Characters;
using Novelly.Api.Common.Validation;
using Novelly.Api.Data;
using Novelly.Api.Imports;
using Novelly.Api.Projects;
using Novelly.Api.Questions;
using Novelly.Api.Scenes;
using Novelly.Api.Tags;

namespace Novelly.Api.Common;

/// <summary>
/// Wires up every feature's services in one place. Endpoints, the embedded agent and the
/// MCP server all resolve the same instances, so a capability added here is available to
/// all three.
/// </summary>
public static class NovellyServiceRegistration
{
    public static IServiceCollection AddNovelly(this IServiceCollection services, IConfiguration configuration)
    {
        var connectionString = configuration.GetConnectionString("Novel")
            ?? "Data Source=novel.db";

        services.AddDbContext<NovelDbContext>(options => options.UseSqlite(connectionString));
        services.AddScoped<INovelDbContext>(sp => sp.GetRequiredService<NovelDbContext>());

        services.AddScoped<ProjectService>();
        services.AddScoped<CharacterService>();
        services.AddScoped<CharacterArcService>();
        services.AddScoped<BeatService>();
        services.AddScoped<TagService>();
        services.AddScoped<ChapterService>();
        services.AddScoped<SceneService>();
        services.AddScoped<OpenQuestionService>();
        services.AddScoped<NovelAgentToolset>();
        services.AddScoped<NovelAgentService>();

        services.Configure<AgentOptions>(configuration.GetSection(AgentOptions.SectionName));
        services.AddScoped<IAgentModelClient, AnthropicAgentModelClient>();

        // A single unbounded queue shared by the request path (writer, in ImportService)
        // and the background runner (reader) — the only background-job infra in the app.
        services.AddSingleton(Channel.CreateUnbounded<Guid>());
        services.AddScoped<ImportService>();
        services.AddScoped<ImportAgentToolset>();
        services.AddScoped<ImportAgentService>();
        services.AddHostedService<ImportJobRunner>();

        services.AddModelValidatorsFromAssemblyContaining<Program>();

        return services;
    }
}