using CPRNIMS.Infrastructure.Database;
using CPRNIMS.Infrastructure.Entities.Common;
using CPRNIMS.WebApi.Exceptions;
using System.Security.Claims;
using System.Text.Json;

namespace CPRNIMS.Middleware
{
    public sealed class GlobalExceptionMiddleware
    {
        private readonly RequestDelegate _next;
        private readonly ILogger<GlobalExceptionMiddleware> _logger;
        private readonly IWebHostEnvironment _env;
        private readonly IServiceScopeFactory _scopeFactory;
        public GlobalExceptionMiddleware(
            RequestDelegate next,
            ILogger<GlobalExceptionMiddleware> logger,
            IWebHostEnvironment env,
            IServiceScopeFactory scopeFactory)
        {
            _next = next;
            _logger = logger;
            _env = env;
            _scopeFactory = scopeFactory;
        }

        public async Task InvokeAsync(HttpContext context)
        {
            try
            {
                await _next(context);
            }
            catch (Exception ex)
            {
                _logger.LogError(ex, "Unhandled exception");

                await LogToDatabaseAsync(context, ex);
                await HandleResponseAsync(context, ex);
            }
        }

        private async Task LogToDatabaseAsync(HttpContext context, Exception ex)
        {
            using var scope = _scopeFactory.CreateScope();
            var db = scope.ServiceProvider.GetRequiredService<NonInventoryDbContext>();

            var errorLog = new ErrorLog
            {
                Id = Guid.NewGuid(),
                Path = context.Request.Path,
                HttpMethod = context.Request.Method,
                QueryString = context.Request.QueryString.Value,
                StatusCode = context.Response.StatusCode,
                ExceptionType = ex.GetType().FullName!,
                Message = ex.Message,
                StackTrace = ex.StackTrace,
                UserId = context.User?.FindFirst(ClaimTypes.NameIdentifier)?.Value,
                IpAddress = context.Connection.RemoteIpAddress?.ToString(),
                CreatedAt = DateTime.UtcNow
            };

            db.ErrorLogs.Add(errorLog);
            await db.SaveChangesAsync();
        }

        private async Task HandleResponseAsync(HttpContext context, Exception ex)
        {
            context.Response.ContentType = "application/json";

            context.Response.StatusCode = ex switch
            {
                AppException app => app.StatusCode,
                ArgumentException => StatusCodes.Status400BadRequest,
                UnauthorizedAccessException => StatusCodes.Status401Unauthorized,
                _ => StatusCodes.Status500InternalServerError
            };

            var response = new
            {
                success = false,
                message = _env.IsDevelopment()
                    ? ex.Message
                    : "An unexpected error occurred"
            };

            await context.Response.WriteAsync(JsonSerializer.Serialize(response));
        }
    }
}