using DocumentService.Client.Configuration;
using DocumentService.Client.Extensions;
using DocumentService.Client.Interfaces;
using DocumentService.Client.Models.ValueObjects;
using Microsoft.Extensions.DependencyInjection;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace DocumentService.Client;

/// <summary>
/// Static entry point for configuring and building the DocumentService client.
/// </summary>
public static class Client
{
    private static Action<DocumentServiceClientOptions> Options { get; set; } = null!;

    private static readonly Lazy<IServiceProvider> LazyProvider = new(() =>
    {
        var services = new ServiceCollection();
        services.AddDocumentServiceClients(Options);
        return services.BuildServiceProvider();
    });

    public static bool IsConfigured => LazyProvider.IsValueCreated;

    public static OnReconfigure OnReconfigure { get; set; } = OnReconfigure.ThrowException;

    /// <summary>
    /// Configures the client using a full <see cref="DocumentServiceClientOptions"/> action.
    /// </summary>
    /// <param name="configuration">Action that configures the client options.</param>
    public static void Configure(Action<DocumentServiceClientOptions> configuration)
    {
        if(IsConfigured)
            switch (OnReconfigure)
            {
                case OnReconfigure.ThrowException:
                    throw new InvalidOperationException("DocumentService.Client is already configured. Reconfiguration is not allowed.");
                case OnReconfigure.Ignore:
                    return;
            }
        Options = configuration;
        _ = LazyProvider.Value; // init service provider
    }

    /// <summary>
    /// Configures the client with only a base URL. Use the overload with options action for full control.
    /// </summary>
    /// <param name="baseUrl">Base URL of the DocumentService API.</param>
    public static void Configure(string baseUrl)
    {
        if (IsConfigured)
            switch (OnReconfigure)
            {
                case OnReconfigure.ThrowException:
                    throw new InvalidOperationException("DocumentService.Client is already configured. Reconfiguration is not allowed.");
                case OnReconfigure.Ignore:
                    return;
            }

        Options = options => {
            options = new DocumentServiceClientOptions
            {
                BaseUrl = baseUrl
            };
        };
        _ = LazyProvider.Value; // init service provider
    }

    private static IServiceProvider Provider => IsConfigured 
        ? LazyProvider.Value 
        : throw new InvalidOperationException("DocumentService.Client is not configured.");

    private static T GetRequiredServiceOfScope<T>() where T : notnull => Provider.CreateAsyncScope().ServiceProvider.GetRequiredService<T>();

    #region Controllers
    public static IPdfAttachmentClient Attachment => GetRequiredServiceOfScope<IPdfAttachmentClient>();

    public static IPdfConversionClient Conversion => GetRequiredServiceOfScope<IPdfConversionClient>();

    public static IPdfOperationsClient Operations => GetRequiredServiceOfScope<IPdfOperationsClient>();

    public static IPdfValidationClient Validation => GetRequiredServiceOfScope<IPdfValidationClient>();

    public static ISwissQrCodeClient SwissQrCode => GetRequiredServiceOfScope<ISwissQrCodeClient>();

    public static IZugferdClient Zugferd => GetRequiredServiceOfScope<IZugferdClient>();
    #endregion
}