function asArray(value) {
  if (Array.isArray(value)) return value;
  if (value == null || value === '') return [];
  return [value];
}

function asNumber(value, fallback = 0) {
  const number = Number(value);
  return Number.isFinite(number) ? number : fallback;
}

function clampPercent(value) {
  return Math.max(0, Math.min(100, asNumber(value)));
}

function formatDateTime(value) {
  if (!value) return '—';
  const date = new Date(value);
  if (Number.isNaN(date.getTime())) return String(value);
  const pad = (number) => String(number).padStart(2, '0');
  return `${date.getFullYear()}-${pad(date.getMonth() + 1)}-${pad(date.getDate())} ${pad(date.getHours())}:${pad(date.getMinutes())}:${pad(date.getSeconds())}`;
}

function containsAbnormalText(value) {
  return /(异常|失败|取消|作废|拒绝|未通过|超时)/.test(String(value || ''));
}

function normalizeStage(stage, index = 0) {
  const source = stage && typeof stage === 'object' ? stage : {};
  const stageStatus = asNumber(source.stageStatus, -1);
  const totalUnits = Math.max(0, asNumber(source.totalUnits));
  const checkedUnits = Math.max(0, asNumber(source.checkedUnits));
  const rawPercent = asNumber(source.progressPercent);
  const isAbnormal = ![1, 2, 3, 4].includes(stageStatus) || checkedUnits > totalUnits || rawPercent < 0 || rawPercent > 100 || containsAbnormalText(source.stageStatusText);
  const athleteNames = asArray(source.athleteNames);
  return Object.assign({}, source, {
    stageKey: source.stageKey || `${source.eventProjectId || 'project'}-${source.groupId || 'group'}-${index}`,
    stageStatus,
    totalUnits,
    checkedUnits,
    progressPercent: clampPercent(rawPercent),
    displayName: source.displayName || [source.projectName, source.groupName].filter(Boolean).join(' - ') || '未命名项目',
    stageStatusText: source.stageStatusText || (isAbnormal ? '状态异常' : '等待中'),
    athleteNames,
    athleteNamesText: athleteNames.join('、') || '—',
    isAbnormal,
    statusClass: isAbnormal ? 'abnormal' : `status-${stageStatus}`
  });
}

function normalizeRound(round) {
  const source = round && typeof round === 'object' ? round : {};
  const passed = source.passed === true;
  const isAbnormal = containsAbnormalText(source.statusText || source.checkinStatusText);
  return Object.assign({}, source, {
    checkinNo: asNumber(source.checkinNo),
    checkinName: source.checkinName || `${asNumber(source.checkinNo)}检`,
    passed,
    checkedTimeText: passed ? formatDateTime(source.checkedTime) : '待完成',
    checkerNameText: passed ? (source.checkerName || '—') : '—',
    isAbnormal,
    statusClass: isAbnormal ? 'abnormal' : (passed ? 'passed' : 'pending')
  });
}

function normalizeMine(item) {
  const source = item && typeof item === 'object' ? item : {};
  const checkinStatus = asNumber(source.checkinStatus, -1);
  const isAbnormal = ![0, 1, 2, 3].includes(checkinStatus) || containsAbnormalText(source.checkinStatusText) || containsAbnormalText(source.notice);
  const athleteNames = asArray(source.athleteNames);
  return Object.assign({}, source, {
    checkinStatus,
    displayName: source.displayName || [source.projectName, source.groupName].filter(Boolean).join(' - ') || '未命名项目',
    athleteNames,
    athleteNamesText: athleteNames.join('、') || '—',
    rounds: asArray(source.rounds).map(normalizeRound),
    checkinStatusText: source.checkinStatusText || (isAbnormal ? '状态异常' : '等待中'),
    isAbnormal,
    statusClass: isAbnormal ? 'abnormal' : `status-${checkinStatus}`
  });
}

function normalizeCheckinProgress(payload) {
  const source = payload && typeof payload === 'object' ? payload : {};
  const stages = asArray(source.stages).map((stage, index) => normalizeStage(stage, index));
  const mine = asArray(source.mine).map(normalizeMine);
  const currentCheckin = source.currentCheckin ? normalizeStage(source.currentCheckin) : null;
  const currentCompeting = source.currentCompeting ? normalizeStage(source.currentCompeting) : null;
  const competingMine = currentCompeting && mine.find((item) =>
    String(item.eventProjectId) === String(currentCompeting.eventProjectId) &&
    String(item.groupId || '') === String(currentCompeting.groupId || '')
  );
  const currentCompetingDetail = currentCompeting ? Object.assign({}, currentCompeting, {
    unitNameText: currentCompeting.unitName || (competingMine && competingMine.unitName) || '—',
    teamNameText: currentCompeting.teamName || (competingMine && competingMine.teamName) || '—',
    athleteNamesText: currentCompeting.athleteNamesText !== '—'
      ? currentCompeting.athleteNamesText
      : ((competingMine && competingMine.athleteNamesText) || '—'),
    registrationTypeText: currentCompeting.registrationTypeText || '个人报名'
  }) : null;
  return Object.assign({}, source, {
    eventName: source.eventName || '检录进度',
    serverTimeText: source.serverTimeText || formatDateTime(source.serverTime),
    weekDayText: source.weekDayText || '',
    currentCheckin,
    currentCompeting,
    currentCompetingDetail,
    stages,
    mine,
    hasData: !!currentCheckin || !!currentCompeting || stages.length > 0 || mine.length > 0
  });
}

module.exports = { normalizeCheckinProgress };