export const runtime = 'nodejs'
import { NextResponse } from 'next/server'
import { PrismaClient } from '@/app/generated/prisma'
import { auth } from '@/auth'
import fs from 'fs/promises'
import path from 'path'
import { parse } from 'csv-parse/sync'

function parseKoreanDateToISO(dateStr: string): string | null {
  // 입력 예: '2025. 9. 1.' → ISO YYYY-MM-DDT00:00:00.000Z (로컬 기준 단순화)
  const m = dateStr?.match(/^(\d{4})\.\s*(\d{1,2})\.\s*(\d{1,2})\.?$/);
  if (!m) return null;
  const yyyy = Number(m[1]);
  const mm = Number(m[2]);
  const dd = Number(m[3]);
  // UTC 자정으로 맞춤
  const d = new Date(Date.UTC(yyyy, mm - 1, dd, 0, 0, 0));
  return d.toISOString();
}

function toInt(v: any): number {
  if (v == null) return 0;
  if (typeof v === 'number') return Math.floor(v);
  const s = String(v).replace(/,/g, '').trim();
  const n = Number(s);
  return Number.isFinite(n) ? Math.floor(n) : 0;
}

export async function GET(request: Request) {
  try {
    // 세션 사용자 확인 (핸들 매핑용)
    const session = await auth();
    if (!session?.user?.email) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
    }

    const { searchParams } = new URL(request.url)
    const dateParam = searchParams.get('date') || 'latest'

    let rows: any[] = []
    let dateStr: string | undefined = undefined

    if (dateParam === 'files') {
      // Read from local CSV and use fixed date 250831
      const filePath = path.join(process.cwd(), 'datas', 'to0831.csv')
      const csv = await fs.readFile(filePath, 'utf-8')
      rows = parse(csv, {
        columns: true,
        skip_empty_lines: true,
        bom: true,
        relax_column_count: true,
        trim: true,
      }) as any[]
      dateStr = '250831'
    } else {
      const upstream = await fetch(`http://localhost:9556/data?date=${encodeURIComponent(dateParam)}`, {
        method: 'GET',
      })
      const text = await upstream.text()
      let data: any = null
      try {
        data = text ? JSON.parse(text) : null
      } catch {
        data = { message: text }
      }
      rows = Array.isArray(data?.data) ? data.data : []
      dateStr = data?.date
      if (!dateStr) {
        return NextResponse.json({ error: 'invalid upstream payload' }, { status: 502 })
      }
    }

    // 유효성 체크
    if (!dateStr || rows.length === 0) {
      return NextResponse.json({ error: 'invalid upstream payload' }, { status: 502 })
    }
    if (rows.length <= 1) {
      return NextResponse.json({ success: true, message: 'no rows to import', date: dateStr })
    }

    // Convert date string: supports 'YYYY. M. D.' or 'YYMMDD'
    const parseYYMMDD = (s: string): string | null => {
      const m = s.match(/^(\d{2})(\d{2})(\d{2})$/)
      if (!m) return null
      const yyyy = 2000 + Number(m[1])
      const mm = Number(m[2])
      const dd = Number(m[3])
      return new Date(Date.UTC(yyyy, mm - 1, dd, 0, 0, 0)).toISOString()
    }

    const isoDate = parseKoreanDateToISO(dateStr) || parseYYMMDD(dateStr) || new Date().toISOString();
    const prisma = new PrismaClient();
    try {
      // handle 연결은 비워둠 (요청에 따라 핸들 매핑 생략)

      let upserted = 0;
      // 2번째 행부터 반영
      for (let i = 1; i < rows.length; i++) {
        const row = rows[i] || {};
        const contentId: string | undefined = row['콘텐츠'] ?? row['contentId'] ?? row['콘텐츠 ID'];
        const subject: string = row['동영상 제목'] ?? row['제목'] ?? row['title'] ?? row['동영상'] ?? `content-${i}`;
        const publishAtRaw: string | undefined = row['동영상 게시 시간'] ?? row['게시 시간'] ?? row['publishedAt'];
        const publishAtDate = publishAtRaw ? new Date(publishAtRaw) : new Date(isoDate);

        // Content upsert: id=콘텐츠, subject=동영상 제목, pubDate=동영상 게시 시간
        const upsertedContent = await prisma.content.upsert({
          where: { id: String(contentId ?? `content-${i}`) },
          update: {
            subject,
            pubDate: publishAtDate,
          },
          create: {
            id: String(contentId ?? `content-${i}`),
            subject,
            pubDate: publishAtDate,
            // handle 연결 없음
          },
          select: { id: true },
        });

        const views = toInt(row['조회수']);
        const validViews = toInt(row['유효 조회수']);
        const premiumViews = toInt(row['YouTube Premium 조회수']);
        const watchTime = toInt(row['시청 시간(단위: 시간)']);

        // contentId + date 복합 유니크로 upsert
        await prisma.contentDayView.upsert({
          where: { contentId_date: { contentId: upsertedContent.id, date: new Date(isoDate) } },
          update: { views, validViews, premiumViews, watchTime },
          create: {
            contentId: upsertedContent.id,
            date: new Date(isoDate),
            views,
            validViews,
            premiumViews,
            watchTime,
          },
        });
        upserted += 1;
      }

      return NextResponse.json({ success: true, date: dateStr, upserted, data: rows })
    } finally {
      try { await (prisma as any).$disconnect() } catch {}
    }
  } catch (e) {
    console.error('contents/update upstream error:', e)
    return NextResponse.json({ error: '업스트림 요청 실패' }, { status: 502 })
  }
}