package main

import (
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"strings"
)

type CreateBookRequest struct {
	Title  string  `json:"title"`
	Author string  `json:"author"`
	Price  float64 `json:"price"`
}

// validate — birinchi topilgan xatoni qaytaradi, hammasi to'g'ri bo'lsa "" qaytaradi
func validate(req CreateBookRequest) string {
	if strings.TrimSpace(req.Title) == "" {
		return "title bo'sh bo'lishi mumkin emas"
	}
	if strings.TrimSpace(req.Author) == "" {
		return "author bo'sh bo'lishi mumkin emas"
	}
	if req.Price <= 0 {
		return "price musbat son bo'lishi kerak"
	}
	return ""
}

func createHandler(w http.ResponseWriter, r *http.Request) {
	var req CreateBookRequest
	json.NewDecoder(r.Body).Decode(&req)

	if msg := validate(req); msg != "" {
		w.WriteHeader(http.StatusUnprocessableEntity)
		fmt.Fprint(w, msg)
		return
	}

	w.WriteHeader(http.StatusCreated)
	fmt.Fprint(w, "yaratildi")
}

func main() {
	req := httptest.NewRequest("POST", "/books", strings.NewReader(`{"title":"Go bilan tanishuv","price":45000}`))
	rec := httptest.NewRecorder()
	createHandler(rec, req)
	fmt.Println(rec.Code, rec.Body.String())
}