import { type ClassValue, clsx } from "clsx";
import { DateTime } from "luxon";
import type { NavigateFunction } from "react-router";
import { twMerge } from "tailwind-merge";

export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs));
}

/**
 * === STRING UTILS ===
 */
export function capitalizeFirstLetter(str: string): string {
  return str.charAt(0).toUpperCase() + str.slice(1);
}

export function titleCase(str: string) {
  return str.replace(
    /\w\S*/g,
    (text) => text.charAt(0).toUpperCase() + text.substring(1).toLowerCase()
  );
}

/**
 * === NAVIGATION UTILS ===
 */
// Force a reload of the page
export function forceReload() {
  window.location.reload();
}

export function goBack(navigate: NavigateFunction) {
  let canGoBack = false;
  // Check if there is a history stack to go back to
  try {
    canGoBack = window.history.length > 1;
  } catch (e) {
    canGoBack = false;
  }
  if (!canGoBack) {
    return navigate("/");
  } else {
    return navigate(-1);
  }
}

/**
 * === COLLES UTILS ===
 */
export const formatDate = (date: string) => {
  const dt = DateTime.fromISO(date).setLocale("fr");
  const str = dt.toLocaleString({
    weekday: "long",
    day: "numeric",
    month: "long",
    year: "numeric",
  });
  return titleCase(str);
};

export const formatTime = (date: string) => {
  const dt = DateTime.fromISO(date).setLocale("fr");
  return dt.toLocaleString({
    hour: "2-digit",
    minute: "2-digit",
  })?.replace(":", "h") || "N/A";
};

export const formatGrade = (grade?: number) => {
  if (grade === undefined || grade === null || grade < 0 || grade > 20)
    return "N/A";

  const rounded = Math.round(grade * 10) / 10;
  const str =
    rounded % 1 === 0
      ? rounded.toFixed(0) // no decimals if .0
      : rounded.toFixed(1); // one decimal otherwise

  return str.replace(".", ",").padStart(2, "0"); // pad with zero if needed
};