import { defineEventHandler, getQuery } from 'h3'
import { query } from '../../../utils/db'

/**
 * 주차별 취합 목록
 * GET /api/report/summary/weekly-list
 */
export default defineEventHandler(async (event) => {
  const queryParams = getQuery(event)
  const year = queryParams.year ? parseInt(queryParams.year as string) : new Date().getFullYear()
  
  // 주차별로 그룹핑
  const rows = await query(`
    SELECT 
      s.report_year,
      s.report_week,
      COUNT(DISTINCT s.project_id) as project_count,
      SUM(s.member_count) as total_members,
      SUM(COALESCE(s.total_work_hours, 0)) as total_work_hours,
      MAX(s.aggregated_at) as latest_aggregated_at,
      ARRAY_AGG(DISTINCT p.project_name ORDER BY p.project_name) as project_names
    FROM wr_aggregated_report_summary s
    JOIN wr_project_info p ON s.project_id = p.project_id
    WHERE s.report_year = $1
    GROUP BY s.report_year, s.report_week
    ORDER BY s.report_week DESC
  `, [year])
  
  return {
    weeks: rows.map((r: any) => {
      const { monday, sunday } = getWeekDates(r.report_year, r.report_week)
      return {
        reportYear: r.report_year,
        reportWeek: r.report_week,
        weekStartDate: monday,
        weekEndDate: sunday,
        projectCount: parseInt(r.project_count),
        totalMembers: parseInt(r.total_members),
        totalWorkHours: parseFloat(r.total_work_hours) || 0,
        latestAggregatedAt: r.latest_aggregated_at,
        projects: r.project_names || []
      }
    })
  }
})

// ISO 8601 주차 기준 월요일~일요일 계산
function getWeekDates(year: number, week: number): { monday: string, sunday: string } {
  // 해당 연도의 1월 4일이 속한 주가 1주차 (ISO 8601)
  const jan4 = new Date(year, 0, 4)
  const jan4DayOfWeek = jan4.getDay() || 7 // 일요일=7
  
  // 1주차의 월요일
  const week1Monday = new Date(jan4)
  week1Monday.setDate(jan4.getDate() - jan4DayOfWeek + 1)
  
  // 요청된 주차의 월요일
  const monday = new Date(week1Monday)
  monday.setDate(week1Monday.getDate() + (week - 1) * 7)
  
  // 일요일
  const sunday = new Date(monday)
  sunday.setDate(monday.getDate() + 6)
  
  return {
    monday: formatDate(monday),
    sunday: formatDate(sunday)
  }
}

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