/**
 * Duty list (timeline) rendering.
 */

import { dutyListEl, state } from "./dom.js";
import { EVENT_TYPE_LABELS } from "./constants.js";
import { escapeHtml } from "./utils.js";
import {
  localDateString,
  firstDayOfMonth,
  lastDayOfMonth,
  dateKeyToDDMM,
  formatTimeLocal,
  formatDateKey
} from "./dateUtils.js";

/**
 * Build HTML for one timeline duty card: one-day "DD.MM, HH:MM – HH:MM" or multi-day.
 * @param {object} d - Duty
 * @param {boolean} isCurrent - Whether this is "current" duty
 * @returns {string}
 */
export function dutyTimelineCardHtml(d, isCurrent) {
  const startLocal = localDateString(new Date(d.start_at));
  const endLocal = localDateString(new Date(d.end_at));
  const startDDMM = dateKeyToDDMM(startLocal);
  const endDDMM = dateKeyToDDMM(endLocal);
  const startTime = formatTimeLocal(d.start_at);
  const endTime = formatTimeLocal(d.end_at);
  let timeStr;
  if (startLocal === endLocal) {
    timeStr = startDDMM + ", " + startTime + " – " + endTime;
  } else {
    timeStr = startDDMM + " " + startTime + " – " + endDDMM + " " + endTime;
  }
  const typeLabel = isCurrent
    ? "Сейчас дежурит"
    : (EVENT_TYPE_LABELS[d.event_type] || "Дежурство");
  const extraClass = isCurrent ? " duty-item--current" : "";
  return (
    '<div class="duty-item duty-item--duty duty-timeline-card' +
    extraClass +
    '"><span class="duty-item-type">' +
    escapeHtml(typeLabel) +
    '</span> <span class="name">' +
    escapeHtml(d.full_name) +
    '</span><div class="time">' +
    escapeHtml(timeStr) +
    "</div></div>"
  );
}

/**
 * Build HTML for one duty card.
 * @param {object} d - Duty
 * @param {string} [typeLabelOverride] - e.g. "Сейчас дежурит"
 * @param {boolean} [showUntilEnd] - Show "до HH:MM" instead of range
 * @param {string} [extraClass] - e.g. "duty-item--current"
 * @returns {string}
 */
export function dutyItemHtml(d, typeLabelOverride, showUntilEnd, extraClass) {
  const typeLabel =
    typeLabelOverride != null
      ? typeLabelOverride
      : (EVENT_TYPE_LABELS[d.event_type] || d.event_type);
  let itemClass = "duty-item duty-item--" + (d.event_type || "duty");
  if (extraClass) itemClass += " " + extraClass;
  let timeOrRange = "";
  if (showUntilEnd && d.event_type === "duty") {
    timeOrRange = "до " + formatTimeLocal(d.end_at);
  } else if (d.event_type === "vacation" || d.event_type === "unavailable") {
    const startStr = formatDateKey(d.start_at);
    const endStr = formatDateKey(d.end_at);
    timeOrRange = startStr === endStr ? startStr : startStr + " – " + endStr;
  } else {
    timeOrRange =
      formatTimeLocal(d.start_at) + " – " + formatTimeLocal(d.end_at);
  }
  return (
    '<div class="' +
    itemClass +
    '"><span class="duty-item-type">' +
    escapeHtml(typeLabel) +
    '</span> <span class="name">' +
    escapeHtml(d.full_name) +
    '</span><div class="time">' +
    timeOrRange +
    "</div></div>"
  );
}

/**
 * Render duty list (timeline) for current month; scroll to today if visible.
 * @param {object[]} duties - Duties (only duty type used for timeline)
 */
export function renderDutyList(duties) {
  if (!dutyListEl) return;
  const filtered = duties.filter((d) => d.event_type === "duty");
  if (filtered.length === 0) {
    dutyListEl.classList.remove("duty-timeline");
    dutyListEl.innerHTML = '<p class="muted">В этом месяце дежурств нет.</p>';
    return;
  }
  dutyListEl.classList.add("duty-timeline");
  const current = state.current;
  const todayKey = localDateString(new Date());
  const firstKey = localDateString(firstDayOfMonth(current));
  const lastKey = localDateString(lastDayOfMonth(current));
  const showTodayInMonth = todayKey >= firstKey && todayKey <= lastKey;
  const dateSet = new Set();
  filtered.forEach((d) => {
    dateSet.add(localDateString(new Date(d.start_at)));
  });
  if (showTodayInMonth) dateSet.add(todayKey);
  const dates = Array.from(dateSet).sort();
  const now = new Date();
  let fullHtml = "";
  dates.forEach((date) => {
    const isToday = date === todayKey;
    const dayClass =
      "duty-timeline-day" + (isToday ? " duty-timeline-day--today" : "");
    const dateLabel = dateKeyToDDMM(date);
    const dateCellHtml = isToday
      ? '<span class="duty-timeline-date"><span class="duty-timeline-date-label">Сегодня</span><span class="duty-timeline-date-day">' +
        escapeHtml(dateLabel) +
        '</span><span class="duty-timeline-date-dot" aria-hidden="true"></span></span>'
      : '<span class="duty-timeline-date">' + escapeHtml(dateLabel) + "</span>";
    const dayDuties = filtered
      .filter((d) => localDateString(new Date(d.start_at)) === date)
      .sort((a, b) => new Date(a.start_at) - new Date(b.start_at));
    let dayHtml = "";
    dayDuties.forEach((d) => {
      const start = new Date(d.start_at);
      const end = new Date(d.end_at);
      const isCurrent = isToday && start <= now && now < end;
      dayHtml +=
        '<div class="duty-timeline-row">' +
        dateCellHtml +
        '<span class="duty-timeline-track" aria-hidden="true"></span><div class="duty-timeline-card-wrap">' +
        dutyTimelineCardHtml(d, isCurrent) +
        "</div></div>";
    });
    if (dayDuties.length === 0 && isToday) {
      dayHtml +=
        '<div class="duty-timeline-row duty-timeline-row--empty">' +
        dateCellHtml +
        '<span class="duty-timeline-track" aria-hidden="true"></span><div class="duty-timeline-card-wrap"></div></div>';
    }
    fullHtml +=
      '<div class="' +
      dayClass +
      '" data-date="' +
      escapeHtml(date) +
      '">' +
      dayHtml +
      "</div>";
  });
  dutyListEl.innerHTML = fullHtml;
  const scrollTarget = dutyListEl.querySelector(".duty-timeline-day--today");
  if (scrollTarget) {
    const calendarSticky = document.getElementById("calendarSticky");
    if (calendarSticky) {
      requestAnimationFrame(() => {
        const calendarHeight = calendarSticky.offsetHeight;
        const todayTop = scrollTarget.getBoundingClientRect().top + window.scrollY;
        const scrollTop = Math.max(0, todayTop - calendarHeight);
        window.scrollTo({ top: scrollTop, behavior: "auto" });
      });
    } else {
      scrollTarget.scrollIntoView({ behavior: "auto", block: "start" });
    }
  }
}