using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using MediatR;
using Microsoft.AspNetCore.Authentication.JwtBearer;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Hosting;
using Microsoft.IdentityModel.Tokens;
using MyHN.Application;
using MyHN.Domain;
using MyHN.Infrastructure;
using MyHN.Infrastructure.Repositories;
using NSwag.Generation.Processors.Security;

namespace Api
{
  /// <summary>
  /// Représente les options nécessaires à la génération / validation
  /// d'un jeton JWT.
  /// </summary>
  public class TokenOptions
  {
    public string Issuer { get; set; }
    public string Audience { get; set; }
    public string SecurityKey { get; set; }

    public SecurityKey Key => new SymmetricSecurityKey(Encoding.UTF8.GetBytes(SecurityKey));
  }

  public class Startup
  {
    public Startup(IConfiguration configuration)
    {
      Configuration = configuration;
    }

    public IConfiguration Configuration { get; }

    // This method gets called by the runtime. Use this method to add services to the container.
    // For more information on how to configure your application, visit https://go.microsoft.com/fwlink/?LinkID=398940
    public void ConfigureServices(IServiceCollection services)
    {
      services.AddMyHNServices(Configuration)
        .AddUserProvider<HttpUserProvider>();

      var tokenOptions = Configuration.GetSection("Token").Get<TokenOptions>();
      services.AddSingleton<TokenOptions>(tokenOptions);

      services.AddIdentityCore<IdentityUser>(options =>
      {
        options.Password.RequiredLength = options.Password.RequiredUniqueChars = 0;
        options.Password.RequireDigit = options.Password.RequireLowercase = options.Password.RequireNonAlphanumeric = options.Password.RequireUppercase = false;
      })
            .AddRoles<IdentityRole>()
            .AddEntityFrameworkStores<MyHNDbContext>()
            .AddSignInManager();

      services.AddAuthentication(JwtBearerDefaults.AuthenticationScheme)
          .AddJwtBearer(options =>
          {
            options.TokenValidationParameters = new TokenValidationParameters
            {
              ValidateIssuer = true,
              ValidateAudience = true,
              ValidateLifetime = true,
              ValidateIssuerSigningKey = true,
              ValidIssuer = tokenOptions.Issuer,
              ValidAudience = tokenOptions.Audience,
              IssuerSigningKey = tokenOptions.Key
            };
          });

      services.AddControllers(options =>
      {
        options.Filters.Add(new CustomExceptionFilter());
      });

      services.AddOpenApiDocument(doc =>
      {
        doc.AddSecurity("JWT", Enumerable.Empty<string>(), new NSwag.OpenApiSecurityScheme()
        {
          Type = NSwag.OpenApiSecuritySchemeType.ApiKey,
          Name = "Authorization",
          In = NSwag.OpenApiSecurityApiKeyLocation.Header,
          Description = "Renseigner votre jeton: Bearer {votre jeton}"
        });

        // doc.OperationProcessors.Add(new AspNetCoreOperationSecurityScopeProcessor("JWT"));

        doc.PostProcess = od =>
        {
          od.Info.Title = "MyHN API Documentation";
        };
      });
    }

    // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
    public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
    {
      MigrateDatabase(app.ApplicationServices);
      app.UseOpenApi();

      if (env.IsDevelopment())
      {
        app.UseDeveloperExceptionPage();
        app.UseSwaggerUi3();
      }

      app.UseCors(o =>
      {
        o.AllowAnyOrigin();
        o.AllowAnyMethod();
        // o.AllowAnyHeader();
        o.WithHeaders("content-type", "authorization");
      });

      app.UseRouting();

      app.UseAuthentication();
      app.UseAuthorization();

      app.UseEndpoints(endpoints =>
      {
        endpoints.MapControllers();
        endpoints.MapGet("/", async context =>
              {
                await context.Response.WriteAsync("Hello World!");
              });
      });
    }

    private void MigrateDatabase(IServiceProvider provider)
    {
      using var scope = provider.CreateScope();
      using var ctx = scope.ServiceProvider.GetRequiredService<MyHNDbContext>();
      ctx.Database.Migrate();
    }
  }
}