const QUARTER_NAME_MAP = {
  1: 'Q1',
  2: 'Q2',
  3: 'Q3',
  4: 'Q4'
}

const CHINESE_QUARTER_MAP = {
  一: 1,
  二: 2,
  三: 3,
  四: 4
}

const BUDGET_REPORT_COLORS = {
  travel: 'var(--theme-primary)',
  meal: 'var(--theme-secondary)',
  office: 'var(--warning)',
  communication: 'var(--info)'
}

const PREVIOUS_QUARTER_SPEND = [
  {
    key: 'travel',
    name: '差旅',
    value: 468000,
    previousValue: 395600,
    recommendedBudget: 550000,
    color: BUDGET_REPORT_COLORS.travel,
    drivers: ['客户现场实施增加', '跨区域项目支持', '住宿单价上浮'],
    risk: 'Q2 差旅占比最高，Q3 如果继续集中出差，建议把提醒阈值放在 75%。',
    suggestion: '建议 Q3 编制 52-56 万，优先锁定核心项目差旅，非项目型出行走事前说明。'
  },
  {
    key: 'meal',
    name: '招待费',
    value: 286000,
    previousValue: 255100,
    recommendedBudget: 320000,
    color: BUDGET_REPORT_COLORS.meal,
    drivers: ['重点客户拜访', '渠道活动增多', '单次人均金额偏高'],
    risk: '招待费增长快于整体费用，容易触发合规说明和客户关联材料补充。',
    suggestion: '建议 Q3 编制 30-32 万，并按客户拓展活动拆分额度，避免月底集中消耗。'
  },
  {
    key: 'office',
    name: '办公用品',
    value: 181600,
    previousValue: 172000,
    recommendedBudget: 200000,
    color: BUDGET_REPORT_COLORS.office,
    drivers: ['新员工入职物资', '会议设备补充', '季度集中采购'],
    risk: '办公用品整体平稳，但集中采购会造成单月占用偏高。',
    suggestion: '建议 Q3 编制 19-20 万，采用月度采购节奏，把一次性采购纳入占用预留。'
  },
  {
    key: 'communication',
    name: '通信',
    value: 98000,
    previousValue: 102800,
    recommendedBudget: 110000,
    color: BUDGET_REPORT_COLORS.communication,
    drivers: ['固定通讯补贴', '项目远程协同', '少量专线费用'],
    risk: '通信费用占比较低且略有下降，适合维持刚性额度。',
    suggestion: '建议 Q3 编制 10-11 万，保留 8% 弹性池用于项目临时通讯支出。'
  }
]

const currency = (value) =>
  Number(value || 0).toLocaleString('zh-CN', {
    minimumFractionDigits: 0,
    maximumFractionDigits: 0
  })

const compactCurrency = (value) => `¥${(Number(value || 0) / 10000).toFixed(1)}万`

const percent = (value, total) => {
  const denominator = Number(total || 0)
  if (!denominator) return '0.0%'
  return `${((Number(value || 0) / denominator) * 100).toFixed(1)}%`
}

function normalizeBudgetText(rawText) {
  return String(rawText || '')
    .replace(/\s+/g, '')
    .toLowerCase()
}

function parseQuarter(rawText) {
  const text = String(rawText || '')
  const qMatch = text.match(/[qQ]\s*([1-4])/)
  if (qMatch) return Number(qMatch[1])

  const numberMatch = text.match(/第?\s*([1-4])\s*(?:季|季度)/)
  if (numberMatch) return Number(numberMatch[1])

  const chineseMatch = text.match(/第?\s*([一二三四])\s*(?:季|季度)/)
  if (chineseMatch) return CHINESE_QUARTER_MAP[chineseMatch[1]] || 0

  return 0
}

function parseYear(rawText) {
  const match = String(rawText || '').match(/(20\d{2})/)
  return match ? Number(match[1]) : 2026
}

function hasExplicitYear(rawText) {
  return /(20\d{2})/.test(String(rawText || ''))
}

function resolvePreviousPeriod(year, quarter) {
  if (quarter > 1) {
    return { year, quarter: quarter - 1 }
  }
  return { year: year - 1, quarter: 4 }
}

export function shouldUseBudgetCompileReport(rawText, options = {}) {
  if (String(options.sessionType || '').trim() !== 'budget') {
    return false
  }
  const text = normalizeBudgetText(rawText)
  const hasTargetPeriod = parseQuarter(rawText) || hasExplicitYear(rawText)
  return Boolean(
    text &&
      /(预算|budget)/.test(text) &&
      /(编制|制定|测算|生成|规划|预算一下|compile|create|plan)/.test(text) &&
      hasTargetPeriod
  )
}

export function buildBudgetCompileReport(rawText, user = {}) {
  const targetYear = parseYear(rawText)
  const parsedQuarter = parseQuarter(rawText)
  const isAnnualBudget = !parsedQuarter
  const targetQuarter = parsedQuarter || 1
  const previous = isAnnualBudget
    ? { year: targetYear - 1, quarter: 0 }
    : resolvePreviousPeriod(targetYear, targetQuarter)
  const periodMultiplier = isAnnualBudget ? 4 : 1
  const totalSpend = PREVIOUS_QUARTER_SPEND.reduce((sum, item) => sum + item.value * periodMultiplier, 0)
  const totalBudget = 1320000 * periodMultiplier
  const recommendedTotal = PREVIOUS_QUARTER_SPEND.reduce((sum, item) => sum + item.recommendedBudget * periodMultiplier, 0)
  const departmentName = String(user.departmentName || user.department || '').trim() || '当前部门'

  const items = PREVIOUS_QUARTER_SPEND.map((item) => {
    const value = item.value * periodMultiplier
    const previousValue = item.previousValue * periodMultiplier
    const recommendedBudget = item.recommendedBudget * periodMultiplier
    const trendValue = item.previousValue
      ? ((value - previousValue) / previousValue) * 100
      : 0
    return {
      ...item,
      value,
      previousValue,
      recommendedBudget,
      amountDisplay: compactCurrency(value),
      display: percent(value, totalSpend),
      share: percent(value, totalSpend),
      trend: `${trendValue >= 0 ? '+' : ''}${trendValue.toFixed(1)}%`,
      trendTone: trendValue >= 10 ? 'risk' : trendValue >= 0 ? 'warn' : 'stable',
      recommendedDisplay: compactCurrency(recommendedBudget),
      editableBudget: recommendedBudget,
      reminderThreshold: item.key === 'communication' || item.key === 'office' ? 60 : 70,
      alertThreshold: item.key === 'communication' || item.key === 'office' ? 70 : 80,
      riskThreshold: item.key === 'communication' || item.key === 'office' ? 80 : 90,
      editNote: item.suggestion
    }
  })

  const topItem = [...items].sort((a, b) => b.value - a.value)[0]
  const growthItem = [...items].sort((a, b) => {
    const aGrowth = a.previousValue ? (a.value - a.previousValue) / a.previousValue : 0
    const bGrowth = b.previousValue ? (b.value - b.previousValue) / b.previousValue : 0
    return bGrowth - aGrowth
  })[0]

  return {
    type: 'budget_compile_analysis',
    title: isAnnualBudget
      ? `${targetYear}年度预算编制前置分析报告`
      : `${targetYear}年${targetQuarter}季度预算编制前置分析报告`,
    subtitle: isAnnualBudget
      ? `基于${previous.year}年度预算执行模拟数据`
      : `基于${previous.year}年${previous.quarter}季度预算执行模拟数据`,
    departmentName,
    targetPeriod: isAnnualBudget ? `${targetYear}年度` : `${targetYear}年${QUARTER_NAME_MAP[targetQuarter]}`,
    basePeriod: isAnnualBudget ? `${previous.year}年度` : `${previous.year}年${QUARTER_NAME_MAP[previous.quarter]}`,
    periodType: isAnnualBudget ? '年度预算' : '季度预算',
    centerValue: compactCurrency(totalSpend),
    centerLabel: isAnnualBudget ? '去年开销' : '上季度开销',
    summary: {
      totalBudget: compactCurrency(totalBudget),
      totalSpend: compactCurrency(totalSpend),
      usageRate: percent(totalSpend, totalBudget),
      recommendedTotal: compactCurrency(recommendedTotal)
    },
    macroInsights: [
      `${isAnnualBudget ? `${previous.year}年度` : `${previous.year}年${previous.quarter}季度`}实际开销 ${compactCurrency(totalSpend)}，预算使用率 ${percent(totalSpend, totalBudget)}，整体仍在可控区间。`,
      `${topItem.name}是最大开销项，占 ${topItem.share}，建议作为${isAnnualBudget ? `${targetYear}年度` : `${targetYear}年${targetQuarter}季度`}预算编制的第一优先级。`,
      `${growthItem.name}环比增长 ${growthItem.trend}，需要在预算说明中提前解释业务驱动，避免后续报销阶段反复补充材料。`
    ],
    items,
    editableDraft: {
      status: 'editing',
      rows: items.map((item) => ({
        key: item.key,
        name: item.name,
        budgetAmount: item.editableBudget,
        reminderThreshold: item.reminderThreshold,
        alertThreshold: item.alertThreshold,
        riskThreshold: item.riskThreshold,
        note: item.editNote
      }))
    },
    recommendations: [
      `建议${isAnnualBudget ? `${targetYear}年度` : `${targetYear}年${targetQuarter}季度`}总预算先按 ${compactCurrency(recommendedTotal)} 编制，再预留 5%-8% 部门机动池。`,
      '差旅和招待费采用更早的提醒阈值，通信和办公用品保持稳定额度，避免把预算过度分散到低波动项目。',
      '正式编制时建议把重点项目、客户活动和集中采购计划写入预算说明，后续费用控制会更容易解释。'
    ],
    generatedAt: '模拟数据 · 用于 Demo 预览'
  }
}

export async function handleBudgetCompileReportSubmit(runtime) {
  const {
    adjustComposerTextareaHeight,
    clearAttachedFiles,
    completeFlowStep,
    composerBusinessTimeDraftTouched,
    composerBusinessTimeTags,
    composerDraft,
    createMessage,
    currentUser,
    fileInputRef,
    fileNames,
    messages,
    nextTick,
    options,
    persistSessionState,
    rawText,
    replaceMessage,
    resetFlowRun,
    scrollToBottom,
    startFlowStep,
    submitting,
    userText
  } = runtime
  const analysisStartedAt = Date.now()
  resetFlowRun()
  startFlowStep('budget-prior-quarter-analysis', {
    title: '上季度预算开销分析',
    tool: 'budget.analysis.previous_quarter',
    detail: '正在汇总上季度费用占比、增长点和下一季度编制建议...'
  })
  startFlowStep('budget-compile-guidance', {
    title: '预算编制建议生成',
    tool: 'budget.compile.recommendation',
    detail: '正在生成预算编制前置分析报告...'
  })
  if (!options.skipUserMessage) {
    messages.value.push(createMessage('user', userText, fileNames))
  }
  const pendingMessage = createMessage(
    'assistant',
    '我先不直接进入预算表单，先执行上季度预算开销结构分析，再给您一版下一季度预算编制建议。',
    [],
    { meta: ['预算分析中'] }
  )
  messages.value.push(pendingMessage)
  composerDraft.value = ''
  composerBusinessTimeTags.value = []
  composerBusinessTimeDraftTouched.value = false
  clearAttachedFiles()
  if (fileInputRef.value) {
    fileInputRef.value.value = ''
  }
  submitting.value = true
  nextTick(() => {
    adjustComposerTextareaHeight()
    scrollToBottom()
  })
  persistSessionState()

  try {
    await new Promise((resolve) => setTimeout(resolve, 360))
    const budgetReport = buildBudgetCompileReport(rawText, currentUser.value || {})
    completeFlowStep(
      'budget-prior-quarter-analysis',
      '已完成上季度费用占比、增长点和风险点分析',
      Date.now() - analysisStartedAt
    )
    completeFlowStep(
      'budget-compile-guidance',
      '已生成下一季度预算编制建议',
      Date.now() - analysisStartedAt
    )
    replaceMessage(pendingMessage.id, createMessage(
      'assistant',
      '下面先按上季度模拟数据做一版预算编制前置分析。正式接入预算池后，这里会替换成真实部门预算和报销消耗数据。',
      [],
      {
        meta: ['预算分析报告', '模拟数据'],
        budgetReport
      }
    ))
    persistSessionState()
  } finally {
    submitting.value = false
    nextTick(scrollToBottom)
  }
  return null
}