const memoryCards = require('../../data/memoryCards')
const { chapterRoute } = require('../../utils/chapterRoute')

const MEMORY_CARD_ID_PATTERN = /^S\d{2}-C\d{2}-MC\d{2}$/
const INVALID_CARD_MESSAGE = '这回生活观察暂时没有找到。回到封面，还可以慢慢翻一回。'

function normalizeCardId(value) {
  const raw = String(value || '').trim()
  if (!raw || raw.length > 64) return ''
  let decoded = raw
  try {
    decoded = decodeURIComponent(raw)
  } catch (error) {
    return ''
  }
  return MEMORY_CARD_ID_PATTERN.test(decoded) ? decoded : ''
}

function findReportCard(value) {
  const cardId = normalizeCardId(value)
  if (!cardId) return null
  return memoryCards.find((card) => card.cardId === cardId) || null
}

function twoDigits(value) {
  return String(value).padStart(2, '0')
}

Page({
  data: {
    reportCard: null,
    chapterLabel: '',
    invalidCard: false,
    invalidCardMessage: INVALID_CARD_MESSAGE,
  },

  onLoad(options = {}) {
    const reportCard = findReportCard(options.cardId)
    if (!reportCard) {
      this.setData({
        reportCard: null,
        chapterLabel: '',
        invalidCard: true,
      })
      return
    }
    this.setData({
      reportCard: { ...reportCard },
      chapterLabel: `第${twoDigits(reportCard.chapterNumber)}回`,
      invalidCard: false,
    })
  },

  backToChapter() {
    const reportCard = this.data.reportCard
    if (!reportCard || !reportCard.chapterNumber) {
      this.goHome()
      return
    }
    const pages = typeof getCurrentPages === 'function'
      ? getCurrentPages()
      : []
    const previous = pages[pages.length - 2]
    if (
      previous
      && String(previous.route || '').endsWith('/pages/chapter/chapter')
      && typeof wx.navigateBack === 'function'
    ) {
      wx.navigateBack({ delta: 1 })
      return
    }
    wx.navigateTo({
      url: chapterRoute(reportCard.chapterNumber),
    })
  },

  goHome() {
    const target = { url: '/pages/home/home' }
    if (typeof wx.reLaunch === 'function') {
      wx.reLaunch(target)
      return
    }
    wx.redirectTo(target)
  },
})