import type { NextApiRequest, NextApiResponse } from 'next'
import { prisma } from '@/lib/prisma'
import { requireAuth } from '@/lib/auth'

const STOPWORDS = new Set(['from', 'with', 'during', 'this', 'that', 'were', 'found', 'units', 'batch', 'final', 'client', 'reported'])

export default async function handler(req: NextApiRequest, res: NextApiResponse) {
  const user = await requireAuth(req, res)
  if (!user) return
  if (req.method !== 'GET') return res.status(405).end()

  const { category, search, similarTo } = req.query

  // Similar-fix matching: given a description, find resolutions sharing keywords
  if (similarTo) {
    const words = (similarTo as string)
      .toLowerCase()
      .match(/\b\w{4,}\b/g)?.filter(w => !STOPWORDS.has(w)) || []

    if (words.length === 0) return res.json({ data: [] })

    const all = await prisma.resolution.findMany({ orderBy: { createdAt: 'desc' } })
    const matches = all.filter(r => {
      const text = (r.title + ' ' + r.resolution).toLowerCase()
      return words.some(w => text.includes(w))
    })
    return res.json({ data: matches.slice(0, 3) })
  }

  const where: any = {}
  if (category) where.category = category as string
  if (search) {
    where.OR = [
      { title: { contains: search as string, mode: 'insensitive' } },
      { resolution: { contains: search as string, mode: 'insensitive' } },
      { category: { contains: search as string, mode: 'insensitive' } },
    ]
  }

  const resolutions = await prisma.resolution.findMany({ where, orderBy: { createdAt: 'desc' } })
  return res.json({ data: resolutions })
}