export default class TimeManager {
  static format(input) {
    const date = new Date(input)
    if (Number.isNaN(date.getTime())) return ''

    const now = new Date()
    const diffMs = now.getTime() - date.getTime()

    if (diffMs >= 0 && diffMs < 60 * 1000) {
      return '刚刚'
    }

    if (diffMs >= 0 && diffMs < 60 * 60 * 1000) {
      const mins = Math.floor(diffMs / 60_000)
      return `${mins || 1}分钟前`
    }

    const startOfToday = new Date(now.getFullYear(), now.getMonth(), now.getDate())
    const startOfDate = new Date(date.getFullYear(), date.getMonth(), date.getDate())
    const diffDays = Math.floor((startOfToday - startOfDate) / 86400000)

    const hh = date.getHours().toString().padStart(2, '0')
    const mm = date.getMinutes().toString().padStart(2, '0')
    const timePart = `${hh}:${mm}`

    if (diffDays === 0) return `今天 ${timePart}`
    if (diffDays === 1) return `昨天 ${timePart}`
    if (diffDays === 2) return `前天 ${timePart}`

    const month = date.getMonth() + 1
    const day = date.getDate()

    if (date.getFullYear() === now.getFullYear()) {
      return `${month}.${day} ${timePart}`
    }

    if (date.getFullYear() === now.getFullYear() - 1) {
      return `去年 ${month}.${day} ${timePart}`
    }

    return `${date.getFullYear()}.${month}.${day} ${timePart}`
  }

  // 仅显示日期（不含时间）
  static formatWithDay(input) {
    const date = new Date(input)
    if (Number.isNaN(date.getTime())) return ''

    const now = new Date()

    const startOfToday = new Date(now.getFullYear(), now.getMonth(), now.getDate())
    const startOfDate = new Date(date.getFullYear(), date.getMonth(), date.getDate())
    const diffDays = Math.floor((startOfToday - startOfDate) / 86400000)

    if (diffDays === 0) return '今天'
    if (diffDays === 1) return '昨天'
    if (diffDays === 2) return '前天'

    const month = date.getMonth() + 1
    const day = date.getDate()

    if (date.getFullYear() === now.getFullYear()) {
      return `${month}.${day}`
    }

    if (date.getFullYear() === now.getFullYear() - 1) {
      return `去年 ${month}.${day}`
    }

    return `${date.getFullYear()}.${month}.${day}`
  }
}