import { queryOne } from '../../../utils/db'
import { requireAuth, getCurrentUser } from '../../../utils/session'
import { getValidGoogleToken } from '../../../utils/google-token'

/**
 * 구글 그룹 메시지 목록 조회
 * GET /api/google-group/[id]/messages
 */
export default defineEventHandler(async (event) => {
  const user = await requireAuth(event)
  const groupId = parseInt(getRouterParam(event, 'id') || '0')
  const queryParams = getQuery(event)
  
  if (!groupId) {
    throw createError({ statusCode: 400, message: '그룹 ID가 필요합니다.' })
  }
  
  // 그룹 정보 조회
  const group = await queryOne<any>(`
    SELECT group_email, group_name FROM wr_google_group WHERE group_id = $1
  `, [groupId])
  
  if (!group) {
    throw createError({ statusCode: 404, message: '그룹을 찾을 수 없습니다.' })
  }
  
  // Google 토큰 확인
  const accessToken = await getValidGoogleToken(user.employeeId)
  if (!accessToken) {
    throw createError({ 
      statusCode: 401, 
      message: 'Google 계정 연결이 필요합니다.' 
    })
  }
  
  const maxResults = parseInt(queryParams.limit as string) || 20
  const pageToken = queryParams.pageToken as string || ''
  
  try {
    // Gmail API로 그룹 메일 검색
    const searchQuery = encodeURIComponent(`from:${group.group_email} OR to:${group.group_email}`)
    let url = `https://gmail.googleapis.com/gmail/v1/users/me/messages?q=${searchQuery}&maxResults=${maxResults}`
    if (pageToken) url += `&pageToken=${pageToken}`
    
    const listRes = await fetch(url, {
      headers: { Authorization: `Bearer ${accessToken}` }
    })
    
    if (!listRes.ok) {
      throw createError({ statusCode: 500, message: 'Gmail API 오류' })
    }
    
    const listData = await listRes.json()
    const messages: any[] = []
    
    // 각 메시지 상세 정보 조회 (최대 10개)
    for (const msg of (listData.messages || []).slice(0, 10)) {
      const detailRes = await fetch(
        `https://gmail.googleapis.com/gmail/v1/users/me/messages/${msg.id}?format=metadata&metadataHeaders=Subject&metadataHeaders=From&metadataHeaders=Date`,
        { headers: { Authorization: `Bearer ${accessToken}` } }
      )
      
      if (detailRes.ok) {
        const detail = await detailRes.json()
        const headers = detail.payload?.headers || []
        
        messages.push({
          messageId: msg.id,
          threadId: msg.threadId,
          subject: headers.find((h: any) => h.name === 'Subject')?.value || '(제목 없음)',
          from: headers.find((h: any) => h.name === 'From')?.value || '',
          date: headers.find((h: any) => h.name === 'Date')?.value || '',
          snippet: detail.snippet || ''
        })
      }
    }
    
    return {
      group: { groupId, groupEmail: group.group_email, groupName: group.group_name },
      messages,
      nextPageToken: listData.nextPageToken || null
    }
    
  } catch (e: any) {
    throw createError({ statusCode: 500, message: e.message || '메시지 조회 실패' })
  }
})