From f92a529502ea870158fd7913dca3193f2ed7455c Mon Sep 17 00:00:00 2001
From: Nikita Tokarchuk <nikita@tokarch.uk>
Date: Thu, 9 Jan 2020 12:25:15 +0100
Subject: [PATCH] improve first answer validation

---
 task1-backend/lib/api.go | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/task1-backend/lib/api.go b/task1-backend/lib/api.go
index d880748..5d3c803 100644
--- a/task1-backend/lib/api.go
+++ b/task1-backend/lib/api.go
@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"net/http"
+	"regexp"
 	"strings"
 	"time"
 
@@ -35,8 +36,8 @@ type Api struct {
 }
 
 type Answer struct {
-	Answer json.RawMessage `json:"answer"`
-	Name   string          `json:"name"`
+	Answer string `json:"answer"`
+	Name   string `json:"name"`
 }
 
 func (a *Api) GetHandler() fasthttp.RequestHandler {
@@ -85,8 +86,12 @@ func (a *Api) checkAnswer(ctx *routing.Context) (err error) {
 		return routing.NewHTTPError(http.StatusBadRequest, err.Error())
 	}
 
+	cleaner := regexp.MustCompile("[[:^alnum:]]")
+	pure := cleaner.ReplaceAllLiteralString(answer.Answer, "")
+	pure = strings.ToLower(pure)
+
 	hash := sha256.New()
-	hash.Write(answer.Answer)
+	hash.Write([]byte(pure))
 
 	hexed := make([]byte, hex.EncodedLen(sha256.Size))