import { addDaysIso, mondayOf, todayIso } from "@/domain/work-orders/utils/wizard-date-utils";

export interface WorkWeek {
  mondayIso: string;
  label: string;
  live: boolean;
}

export function currentWeekMonday(): string {
  return mondayOf(todayIso());
}

export function weekRange(mondayIso: string): [string, string] {
  return [mondayIso, addDaysIso(mondayIso, 4)];
}

export function compactWeekLabel(mondayIso: string): string {
  if (!/^\d{4}-\d{2}-\d{2}$/.test(mondayIso)) {
    return "";
  }
  const fridayIso = addDaysIso(mondayIso, 4);
  const [, sm, sd] = mondayIso.split("-").map(Number);
  const [, em, ed] = fridayIso.split("-").map(Number);
  return `${sm}/${sd}–${em}/${ed}`;
}

export function isLiveWeek(mondayIso: string): boolean {
  return mondayIso === currentWeekMonday();
}

export function isFutureWeek(mondayIso: string): boolean {
  return mondayIso > currentWeekMonday();
}

export function nextWeekMonday(): string {
  return addDaysIso(currentWeekMonday(), 7);
}

function toWorkWeek(mondayIso: string): WorkWeek {
  return {
    mondayIso,
    label: compactWeekLabel(mondayIso),
    live: isLiveWeek(mondayIso),
  };
}

export function buildWeekWindow(anchorMonday: string, before = 4, after = 4): WorkWeek[] {
  const weeks: WorkWeek[] = [];
  const liveMonday = currentWeekMonday();
  const upcomingMonday = nextWeekMonday();

  for (let i = -before; i <= after; i += 1) {
    const mondayIso = addDaysIso(anchorMonday, i * 7);
    if (isFutureWeek(mondayIso) && mondayIso !== upcomingMonday) {
      continue;
    }
    weeks.push(toWorkWeek(mondayIso));
  }

  for (const requiredMonday of [liveMonday, upcomingMonday]) {
    if (!weeks.some((week) => week.mondayIso === requiredMonday)) {
      weeks.push(toWorkWeek(requiredMonday));
    }
  }

  weeks.sort((a, b) => a.mondayIso.localeCompare(b.mondayIso));
  return weeks;
}