using BlazorApp.Middlewares;
using BlazorApp.Models.Exceptions;
using Microsoft.AspNetCore.Http;
using Microsoft.Extensions.Logging;
using Moq;
using System.Net;
using System.Text;

namespace BlazorApp.Tests.Middlewares
{
    public class ErrorHandlingMiddlewareTests
    {
        private readonly Mock<ILogger<ErrorHandlingMiddleware>> _loggerMock;

        public ErrorHandlingMiddlewareTests()
        {
            _loggerMock = new Mock<ILogger<ErrorHandlingMiddleware>>();
        }

        private HttpContext CreateHttpContext()
        {
            var context = new DefaultHttpContext();
            context.Response.Body = new MemoryStream();
            return context;
        }

        private string GetResponseBody(HttpContext context)
        {
            context.Response.Body.Seek(0, SeekOrigin.Begin);
            using var reader = new StreamReader(context.Response.Body, Encoding.UTF8);
            return reader.ReadToEnd();
        }

        [Fact]
        public async Task Invoke_WhenNotFoundException_Returns404()
        {
            var context = CreateHttpContext();
            RequestDelegate next = (ctx) => throw new NotFoundException("blabla");

            var middleware = new ErrorHandlingMiddleware(next, _loggerMock.Object);

            await middleware.Invoke(context);

            Assert.Equal((int)HttpStatusCode.NotFound, context.Response.StatusCode);
            var body = GetResponseBody(context);
            Assert.Contains("blabla", body);
        }

        [Fact]
        public async Task Invoke_WhenBusinessException_Returns500()
        {
            var context = CreateHttpContext();
            RequestDelegate next = (ctx) => throw new BusinessException("blabla");

            var middleware = new ErrorHandlingMiddleware(next, _loggerMock.Object);

            await middleware.Invoke(context);

            Assert.Equal((int)HttpStatusCode.InternalServerError, context.Response.StatusCode);
            var body = GetResponseBody(context);
            Assert.Contains("blabla", body);
        }

        [Fact]
        public async Task Invoke_WhenValidationException_Returns400()
        {
            var context = CreateHttpContext();
            RequestDelegate next = (ctx) => throw new ValidationException("blabla");

            var middleware = new ErrorHandlingMiddleware(next, _loggerMock.Object);

            await middleware.Invoke(context);

            Assert.Equal((int)HttpStatusCode.BadRequest, context.Response.StatusCode);
            var body = GetResponseBody(context);
            Assert.Contains("blabla", body);
        }

        [Fact]
        public async Task Invoke_WhenUnhandledException_Returns500()
        {
            var context = CreateHttpContext();
            RequestDelegate next = (ctx) => throw new Exception("blabla");

            var middleware = new ErrorHandlingMiddleware(next, _loggerMock.Object);

            await middleware.Invoke(context);

            Assert.Equal((int)HttpStatusCode.InternalServerError, context.Response.StatusCode);
            var body = GetResponseBody(context);
            Assert.Contains("blabla", body);
        }
    }
}