package utils

import (
	"fmt"
	"log"
	"net/http"
)

func Err(w http.ResponseWriter, code int, a ...interface{}) {

	var msg string  // format string for error message
	var hc int      // HTTP error code

	var prefix string = fmt.Sprintf("Error %d - ", code)

	// ATTENTION: the used error codes in this switch statements should be
	// stable. Do not change them, just append to the list!
	switch code {

		case 1:
			msg = "Failed to load recipes from database."
			hc = http.StatusInternalServerError

		case 2:
			msg = "Could not parse recipe from database request."
			hc = http.StatusInternalServerError

		case 3:
			msg = "Exactly 1 'id' URL parameter expected but %d provided."
			hc = http.StatusBadRequest

		case 4:
			msg = "'id' URL parameter '%s' doas not match the regex '%s'."
			hc = http.StatusBadRequest

		case 5:
			msg = "Received error from database: '%s'."
			hc = http.StatusInternalServerError

		case 6:
			msg = "Expected exactly 1 recipe from database but got %d."
			hc = http.StatusInternalServerError

		// deprecated
		case 7:
			msg = "Exactly 1 'type' URL parameter expected but %d provided."
			hc = http.StatusBadRequest

		case 8:
			msg = "Form data does not contain recipe URL (key is '%s')."
			hc = http.StatusBadRequest

		case 9:
			msg = "Could not add recipe: '%s'."
			hc = http.StatusInternalServerError

		case 10:
			msg = "Expected exactly 1 recipe URL in '%s' but got %d (regex is '%s')."
			hc = http.StatusBadRequest

		case 11:
			msg = "Could not get recipe ID from database: '%s'."
			hc = http.StatusInternalServerError

		// deprecated
		case 12:
			msg = "Given recipe type '%s' is unknown."
			hc = http.StatusBadRequest

		default:
			msg = "An unknown error occured."
			hc = http.StatusInternalServerError

	}

	// format full error message
	final := fmt.Sprintf(prefix + msg, a...)

	// send message to log and user
	log.Println(final)
	http.Error(w, final, hc)

}