package orders

import (
	"crypto/rand"
	"encoding/hex"
	"errors"
	"fmt"
	"log"
	"net/http"
	"piekarnikgosipl/data"
	"strconv"
	"strings"
)

type listItem struct {
	id    string
	count int // count multiplied by 10 to allow for half item purchases
}

type order struct {
	id    string
	name  string
	phone string
	items []listItem
}

func newOrderID() string {
	b := make([]byte, 8)
	rand.Read(b)
	return hex.EncodeToString(b)
}

func parseOrder(r *http.Request) (order, error) {
	var o order
	var err error
	var errorList []error
	o.name = strings.TrimSpace(r.PostFormValue("name"))
	if !validName(o.name) {
		errorList = append(errorList, fmt.Errorf("Podaj imię i nazwisko"))
	}
	o.phone, err = parsePhone(r.PostFormValue("phone"))
	if err != nil {
		errorList = append(errorList, err)
	}
	total := 0
	for _, item := range data.Swieta {
		count, err := parseFloat(r.PostFormValue(item.Id))
		if err != nil {
			errorList = append(errorList, fmt.Errorf("Nieprawidłowa ilość dla: %v", item.Name))
			continue
		}
		if count%10 == 5 && !item.Halveable {
			errorList = append(errorList, fmt.Errorf("Produktu %v nie można zamówić w ułamkowej ilości", item.Name))
			continue
		}
		o.items = append(o.items, listItem{item.Id, count})
		price, err := strconv.Atoi(item.Price)
		if err != nil {
			continue
		}
		total += count * price
	}
	if total < 500 {
		errorList = append(errorList, fmt.Errorf("Minimalna wartość zamówienia wynosi 50zł"))
	}
	return o, errors.Join(errorList...)
}

func OrderHandler(w http.ResponseWriter, r *http.Request) {
	r.Body = http.MaxBytesReader(w, r.Body, 16<<10)
	if err := r.ParseForm(); err != nil {
		writeErrors(w, r, http.StatusRequestEntityTooLarge, "Formularz jest nieprawidłowy.")
		return
	}
	o, err := parseOrder(r)
	if err != nil {
		log.Println("ORDER_INVALID", o, err)
		writeErrors(w, r, http.StatusUnprocessableEntity, errorMessages(err)...)
		return
	}
	o.id, err = insertPending(o)
	if err != nil {
		log.Println("ORDER_SHEETS_ERROR", err)
		o.id = newOrderID()
	}
	startCheckout(w, r, o)
}