MireaBackend/Endpoint/Common/Services/UrlHelper.cs

using Microsoft.AspNetCore.Http;
using System;
using System.Linq;

namespace Mirea.Api.Endpoint.Common.Services;

public static class UrlHelper
{
    public static string GetCurrentScheme(this HttpContext context) =>
        context.Request.Headers["X-Forwarded-Proto"].FirstOrDefault() ?? context.Request.Scheme;

    public static string GetCurrentDomain(this HttpContext context) =>
        context.Request.Headers["X-Forwarded-Host"].FirstOrDefault() ?? context.Request.Host.Host;
    public static int? GetCurrentPort(this HttpContext context) =>
        string.IsNullOrEmpty(context.Request.Headers["X-Forwarded-Port"].FirstOrDefault()) ? context.Request.Host.Port :
            int.Parse(context.Request.Headers["X-Forwarded-Port"].First()!);

    private static string CreateSubPath(string? path)
    {
        if (string.IsNullOrEmpty(path))
            return "/";

        return "/" + path.Trim('/') + "/";
    }

    public static string GetSubPath => CreateSubPath(Environment.GetEnvironmentVariable("ACTUAL_SUB_PATH"));

    public static string GetSubPathWithoutFirstApiName
    {
        get
        {
            var path = GetSubPath;

            if (string.IsNullOrEmpty(path) || path == "/")
                return CreateSubPath(null);

            var parts = path.Split('/', StringSplitOptions.RemoveEmptyEntries);

            if (parts[^1].Equals("api", StringComparison.CurrentCultureIgnoreCase))
                parts = parts.Take(parts.Length - 1).ToArray();

            return CreateSubPath(string.Join("/", parts));
        }
    }

    public static string GetSubPathSwagger => CreateSubPath(Environment.GetEnvironmentVariable("SWAGGER_SUB_PATH"));

    public static string GetApiUrl(this HttpContext context, string apiPath = "")
    {
        var scheme = GetCurrentScheme(context);
        var domain = GetCurrentDomain(context).TrimEnd('/').Replace("localhost", "127.0.0.1");

        var port = GetCurrentPort(context);
        var portString = port.HasValue && port != 80 && port != 443 ? $":{port}" : string.Empty;

        return $"{scheme}://{domain}{portString}{GetSubPathWithoutFirstApiName}{apiPath.Trim('/')}";
    }
}