export function dateKey(date: Date) {
  const y = date.getFullYear()
  const m = `${date.getMonth() + 1}`.padStart(2, '0')
  const d = `${date.getDate()}`.padStart(2, '0')
  return `${y}-${m}-${d}`
}

export function habitWeek(now = new Date()) {
  const monday = new Date(now.getFullYear(), now.getMonth(), now.getDate())
  monday.setDate(monday.getDate() - ((monday.getDay() + 6) % 7))
  return Array.from({ length: 7 }, (_, index) => {
    const date = new Date(monday)
    date.setDate(monday.getDate() + index)
    return date
  })
}

export function mergePage<T>(page: T[] | { items?: T[]; next_cursor?: string | null }) {
  if (Array.isArray(page)) return { items: page, nextCursor: null }
  return { items: page.items ?? [], nextCursor: page.next_cursor ?? null }
}

export function isTaskView(view: string) {
  return view === 'tasks' || view === 'today' || view === 'upcoming'
}

export function defaultView() {
  return 'today' as const
}

export function quickTaskFields(view: string, activeList: string, inboxList: string, now = new Date()) {
  if (view !== 'today') return { list_id: activeList }
  const parts = new Intl.DateTimeFormat('en-CA', {
    timeZone: 'Asia/Shanghai',
    year: 'numeric',
    month: '2-digit',
    day: '2-digit',
  }).formatToParts(now)
  const value = (type: Intl.DateTimeFormatPartTypes) => parts.find((part) => part.type === type)?.value
  return {
    list_id: inboxList,
    due_at: `${value('year')}-${value('month')}-${value('day')}T12:00:00+08:00`,
  }
}

export function isHabitComplete(kind: string | undefined, value: number | boolean | undefined, target = 1) {
  if (kind === 'numeric') return Number(value ?? 0) >= target
  return Boolean(value)
}

type HabitSchedule = {
  kind?: string
  cells?: Array<{ day: string; scheduled?: boolean; paused?: boolean; value?: number | boolean }>
}

export function isHabitScheduledToday(habit: HabitSchedule, day: string) {
  const cell = (habit.cells ?? []).find((item) => item.day === day)
  return Boolean(cell?.scheduled && !cell.paused)
}

export function nextHabitSwipeValue(kind: string | undefined, current: number | boolean | undefined, target = 1) {
  const value = Number(current ?? 0)
  if (kind === 'numeric') return Math.min(value + 1, target)
  return value > 0 ? 0 : 1
}

export function previousHabitSwipeValue(kind: string | undefined, current: number | boolean | undefined) {
  const value = Number(current ?? 0)
  if (kind === 'numeric') return Math.max(0, value - 1)
  return 0
}

export function numericHabitInputValue(input: number | string | undefined) {
  if (input === undefined || input === '') return null
  const value = Number(input)
  return Number.isFinite(value) && value >= 0 ? value : null
}

export function countdownDayText(days: number) {
  if (days > 0) return `还有 ${days} 天`
  if (days === 0) return '就是今天'
  return `已经 ${Math.abs(days)} 天`
}

export function countdownKindLabel(kind: string) {
  return ({ countdown: '倒数日', anniversary: '纪念日', birthday: '生日' } as Record<string, string>)[kind] ?? '倒数日'
}

export function calendarModeLabel(mode: string) {
  return mode === 'lunar' ? '农历' : '公历'
}

export function shouldToggleRowSwipe(deltaX: number, deltaY: number) {
  return deltaX >= 64 && deltaX > Math.abs(deltaY) * 1.5
}

export function nextTotalAfterLocalTaskAdd(total: number) {
  return Math.max(0, Number(total) || 0) + 1
}

export function clampFabPosition(x: number, y: number, viewportWidth: number, viewportHeight: number, size = 52, margin = 14, bottomReserved = 74) {
  return {
    x: Math.min(Math.max(x, margin), Math.max(margin, viewportWidth - size - margin)),
    y: Math.min(Math.max(y, margin), Math.max(margin, viewportHeight - size - bottomReserved)),
  }
}

export function isFabDrag(deltaX: number, deltaY: number, threshold = 8) {
  return Math.hypot(deltaX, deltaY) >= threshold
}

export function formatApiErrorDetail(detail: unknown): string {
  if (typeof detail === 'string') return detail
  if (Array.isArray(detail)) {
    const messages = detail.map((item) => {
      if (item && typeof item === 'object') {
        const record = item as Record<string, unknown>
        const location = Array.isArray(record.loc)
          ? record.loc.filter((part) => part !== 'body').join('.')
          : ''
        const message = typeof record.msg === 'string' ? record.msg : JSON.stringify(record)
        return location ? `${location}：${message}` : message
      }
      return String(item)
    })
    return messages.filter(Boolean).join('；') || '请求参数有误'
  }
  if (detail && typeof detail === 'object') {
    const record = detail as Record<string, unknown>
    if ('detail' in record) return formatApiErrorDetail(record.detail)
    return JSON.stringify(record)
  }
  return '请求失败'
}