// services/deal/commentService.js
const { PrismaClient } = require("@prisma/client")
const prisma = new PrismaClient()

function assertPositiveInt(v, name = "id") {
  const n = Number(v)
  if (!Number.isInteger(n) || n <= 0) throw new Error(`Geçersiz ${name}.`)
  return n
}

async function getCommentsByDealId(dealId) {
  const id = assertPositiveInt(dealId, "dealId")

  // Deal mevcut mu kontrol et
  const deal = await prisma.deal.findUnique({ where: { id } })
  if (!deal) throw new Error("Deal bulunamadı.")

  return prisma.comment.findMany({
    where: { dealId: id },
    include: { user: { select: { username: true } } },
    orderBy: { createdAt: "desc" },
  })
}

async function createComment({ dealId, userId, text }) {
  // Basit doğrulamalar
  const dId = assertPositiveInt(dealId, "dealId")
  const uId = assertPositiveInt(userId, "userId")
  if (!text || typeof text !== "string" || !text.trim())
    throw new Error("Yorum boş olamaz.")

  // Deal var mı kontrol et
  const deal = await prisma.deal.findUnique({ where: { id: dId } })
  if (!deal) throw new Error("Deal bulunamadı.")

  // (Opsiyonel) Kullanıcı var mı kontrolü (ek güvenlik)
  const user = await prisma.user.findUnique({ where: { id: uId } })
  if (!user) throw new Error("Kullanıcı bulunamadı.")

  const comment = await prisma.comment.create({
    data: {
      text: text.trim(),
      userId: uId,
      dealId: dId,
    },
    include: {
      user: { select: { username: true } },
    },
  })

  return comment
}

async function deleteComment(commentId, userId) {
  const cId = assertPositiveInt(commentId, "commentId")
  const uId = assertPositiveInt(userId, "userId")

  const comment = await prisma.comment.findUnique({ where: { id: cId } })
  if (!comment) throw new Error("Yorum bulunamadı.")
  if (comment.userId !== uId) throw new Error("Bu yorumu silme yetkin yok.")

  await prisma.comment.delete({ where: { id: cId } })
  return { message: "Yorum silindi." }
}

module.exports = { getCommentsByDealId, createComment, deleteComment }