import { computed, onMounted, ref } from 'vue'

import BudgetTrendChart from '../../components/charts/BudgetTrendChart.vue'
import { fetchEmployeeMeta } from '../../services/employees.js'

const FALLBACK_DEPARTMENTS = [
  { code: 'MARKET-DEPT', name: '市场部', costCenter: 'CC-4100' },
  { code: 'FINANCE-DEPT', name: '财务部', costCenter: 'CC-2100' },
  { code: 'TECH-DEPT', name: '技术部', costCenter: 'CC-6100' },
  { code: 'HR-DEPT', name: '人力资源部', costCenter: 'CC-3200' },
  { code: 'PRODUCTION-DEPT', name: '生产部', costCenter: 'CC-7200' },
  { code: 'PRESIDENT-OFFICE', name: '总裁办', costCenter: 'CC-1000' }
]

const EXPENSE_BLUEPRINTS = [
  { expenseType: '市场推广费', total: 500000, used: 186400, occupied: 120000, warning: 80, action: '提醒' },
  { expenseType: '差旅费', total: 600000, used: 242300, occupied: 150000, warning: 80, action: '提醒' },
  { expenseType: '办公费', total: 300000, used: 68500, occupied: 60000, warning: 70, action: '正常' },
  { expenseType: '培训费', total: 200000, used: 42300, occupied: 20000, warning: 70, action: '正常' },
  { expenseType: '软件服务费', total: 600000, used: 249500, occupied: 240800, warning: 80, action: '管控' }
]

const currency = (value) =>
  Number(value || 0).toLocaleString('zh-CN', {
    minimumFractionDigits: 2,
    maximumFractionDigits: 2
  })

function buildDepartmentRows(departmentCode) {
  const seed = Array.from(String(departmentCode || '')).reduce((sum, char) => sum + char.charCodeAt(0), 0)
  const factor = 0.88 + (seed % 18) / 100

  return EXPENSE_BLUEPRINTS.map((item, index) => {
    const totalAmount = Math.round(item.total * factor)
    const usedAmount = Math.round(item.used * (0.9 + ((seed + index) % 12) / 100))
    const occupiedAmount = Math.round(item.occupied * (0.92 + ((seed + index * 3) % 10) / 100))
    const leftAmount = Math.max(totalAmount - usedAmount - occupiedAmount, 0)
    const rate = Number((((usedAmount + occupiedAmount) / totalAmount) * 100).toFixed(2))

    return {
      ...item,
      totalAmount,
      usedAmount,
      occupiedAmount,
      leftAmount,
      rate,
      rateTone: rate >= item.warning ? 'danger' : rate >= item.warning - 12 ? 'warn' : 'ok',
      warningTone: item.warning >= 80 ? 'budget-warning-red' : 'budget-warning-yellow',
      warningLine: `${item.warning}%`,
      total: currency(totalAmount),
      used: currency(usedAmount),
      occupied: currency(occupiedAmount),
      left: currency(leftAmount)
    }
  })
}

function buildTrendData(rows) {
  const total = rows.reduce((sum, item) => sum + item.totalAmount, 0)
  const used = rows.reduce((sum, item) => sum + item.usedAmount + item.occupiedAmount, 0)

  return {
    labels: ['1月', '2月', '3月', '4月', '5月', '6月', '7月', '8月', '9月', '10月', '11月', '12月'],
    budget: [0.05, 0.18, 0.25, 0.34, 0.45, 0.52, 0.68, 0.76, 0.84, 0.91, 0.96, 1].map((ratio) =>
      Math.round(total * ratio)
    ),
    used: [0.03, 0.1, 0.13, 0.22, 0.3, 0.37, 0.51, 0.59, 0.69, 0.73, 0.86, 0.96].map((ratio) =>
      Math.round(used * ratio)
    )
  }
}

export default {
  name: 'BudgetCenterView',
  components: {
    BudgetTrendChart
  },
  setup() {
    const departments = ref(FALLBACK_DEPARTMENTS)
    const activeDepartmentCode = ref(FALLBACK_DEPARTMENTS[0].code)
    const departmentKeyword = ref('')
    const filters = ref({
      period: '2026年度',
      expenseType: '全部',
      status: '全部'
    })

    const activeDepartment = computed(() =>
      departments.value.find((item) => item.code === activeDepartmentCode.value) || departments.value[0]
    )

    const activeDepartmentName = computed(() => activeDepartment.value?.name || '市场部')
    const departmentRows = computed(() => buildDepartmentRows(activeDepartment.value?.code || activeDepartmentCode.value))
    const visibleBudgetRows = computed(() =>
      departmentRows.value
        .filter((row) => filters.value.expenseType === '全部' || row.expenseType === filters.value.expenseType)
        .filter((row) => {
          if (filters.value.status === '全部') return true
          if (filters.value.status === '预警') return row.rateTone === 'warn'
          if (filters.value.status === '管控') return row.rateTone === 'danger'
          return row.rateTone === 'ok'
        })
    )

    const totals = computed(() => {
      const rows = departmentRows.value
      const total = rows.reduce((sum, item) => sum + item.totalAmount, 0)
      const used = rows.reduce((sum, item) => sum + item.usedAmount, 0)
      const occupied = rows.reduce((sum, item) => sum + item.occupiedAmount, 0)
      return {
        total,
        used,
        occupied,
        left: Math.max(total - used - occupied, 0)
      }
    })

    const budgetMetrics = computed(() => [
      {
        label: '预算总额',
        value: `¥${currency(totals.value.total)}`,
        note: '本年累计',
        tone: 'green',
        icon: 'mdi mdi-wallet-outline'
      },
      {
        label: '已发生',
        value: `¥${currency(totals.value.used)}`,
        note: `占比 ${((totals.value.used / totals.value.total) * 100).toFixed(2)}%`,
        tone: 'blue',
        icon: 'mdi mdi-chart-line'
      },
      {
        label: '已占用',
        value: `¥${currency(totals.value.occupied)}`,
        note: `占比 ${((totals.value.occupied / totals.value.total) * 100).toFixed(2)}%`,
        tone: 'orange',
        icon: 'mdi mdi-briefcase-check-outline'
      },
      {
        label: '剩余可用',
        value: `¥${currency(totals.value.left)}`,
        note: `占比 ${((totals.value.left / totals.value.total) * 100).toFixed(2)}%`,
        tone: 'green',
        icon: 'mdi mdi-currency-cny'
      }
    ])

    const visibleDepartments = computed(() => {
      const keyword = departmentKeyword.value.trim()
      return departments.value
        .filter((item) => !keyword || item.name.includes(keyword) || item.code.includes(keyword))
        .map((item) => ({
          ...item,
          icon: item.code === activeDepartmentCode.value ? 'mdi mdi-account-group-outline' : 'mdi mdi-domain'
        }))
    })

    const warnings = computed(() =>
      departmentRows.value
        .slice()
        .sort((a, b) => b.rate - a.rate)
        .slice(0, 4)
        .map((row, index) => ({
          title: row.expenseType,
          desc: `使用率已达 ${row.rate}%，${row.rate >= row.warning ? '已超过预警线' : '接近预警线'}（${row.warningLine}）`,
          date: index < 2 ? '2026-05-12' : '2026-05-10',
          tone: row.rate >= row.warning ? 'danger' : row.rate >= row.warning - 12 ? 'warn' : 'ok'
        }))
    )

    const trendData = computed(() => buildTrendData(departmentRows.value))

    async function loadDepartments() {
      try {
        const payload = await fetchEmployeeMeta()
        const options = Array.isArray(payload?.organizationOptions) ? payload.organizationOptions : []
        const nextDepartments = options
          .filter((item) => item?.code && item?.name)
          .map((item) => ({
            code: String(item.code),
            name: String(item.name),
            costCenter: String(item.costCenter || '')
          }))

        if (nextDepartments.length) {
          departments.value = nextDepartments
          if (!nextDepartments.some((item) => item.code === activeDepartmentCode.value)) {
            activeDepartmentCode.value = nextDepartments[0].code
          }
        }
      } catch (error) {
        console.warn('Failed to load budget departments from employee meta:', error)
      }
    }

    onMounted(() => {
      void loadDepartments()
    })

    return {
      activeDepartmentCode,
      activeDepartmentName,
      budgetMetrics,
      departmentKeyword,
      expenseTypes: ['全部', ...EXPENSE_BLUEPRINTS.map((item) => item.expenseType)],
      filters,
      periods: ['2026年度', '2026年Q2', '2026年5月'],
      statuses: ['全部', '正常', '预警', '管控'],
      trendData,
      visibleBudgetRows,
      visibleDepartments,
      warnings
    }
  }
}