package apperr

import (
	"errors"
	"log"
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"
)

func Middleware(c *gin.Context) {
	c.Next()

	if len(c.Errors) > 0 {
		// Failsafe default response
		response := ErrorResponse{
			Error: ErrorDetail{
				Code:    http.StatusInternalServerError,
				Message: "Internal Server Error",
			},
		}

		// Iterate over all errors so none are lost in the logs
		for _, ginErr := range c.Errors {
			actualErr := ginErr.Err
			var appErr *Error

			if errors.As(actualErr, &appErr) {
				// We continually overwrite the response, so the final client response is the last error added
				response.Error.Code = appErr.Code
				response.Error.Message = appErr.Message
				response.Error.Details = appErr.Details
				appErr.Log(c)
			} else {
				if c.Writer.Status() != http.StatusOK {
					response.Error.Code = c.Writer.Status()
					response.Error.Message = http.StatusText(c.Writer.Status())
				}
				internalErrStr := strings.ReplaceAll(actualErr.Error(), "\n", " ")
				log.Printf("\033[31m[UNHANDLED ERROR]\033[0m %s %s - %s\n", c.Request.Method, c.Request.URL.Path, internalErrStr)
			}
		}

		// Send formatted JSON for the last error encountered
		if !c.Writer.Written() {
			c.JSON(response.Error.Code, response)
		}

		// Empty the backpack to prevent Gin from duplicating logs via its internal logger
		c.Errors = nil
	}
}