import {
  runSsh,
  shellQuote,
  resolveFolderRemoteDir,
  REMOTE_HOST,
  isSafeFolder,
  isSafeFile
} from "../utils/ssh.ts"
import { spawn } from "node:child_process"

function buildContentDisposition(fileName: string) {
  const asciiName = fileName.replace(/[^\x20-\x7E]/g, "_").replace(/["\\]/g, "_")
  return `attachment; filename="${asciiName}"; filename*=UTF-8''${encodeURIComponent(fileName)}`
}

export default defineEventHandler(async (event) => {
  const { folder, file } = getQuery(event)
  const folderName = typeof folder === "string" ? folder : null
  const fileName = typeof file === "string" ? file : null

  if (!folderName || !fileName) {
    throw createError({ statusCode: 400, statusMessage: "Paramètres manquants" })
  }

  if (!isSafeFolder(folderName) || !isSafeFile(fileName)) {
    throw createError({ statusCode: 400, statusMessage: "Paramètres invalides" })
  }

  const remoteDir = await resolveFolderRemoteDir(folderName)
  if (!remoteDir) {
    throw createError({ statusCode: 404, statusMessage: "Dossier introuvable" })
  }

  const remotePath = `${remoteDir}/${fileName}`
  const existsOutput = await runSsh(`[ -f ${shellQuote(remotePath)} ] && echo yes || echo no`)
  if (existsOutput.trim() !== "yes") {
    throw createError({ statusCode: 404, statusMessage: "Fichier introuvable" })
  }

  setHeader(event, "Content-Type", "application/octet-stream")
  setHeader(event, "Content-Disposition", buildContentDisposition(fileName))

  const child = spawn("ssh", [
    "-o",
    "BatchMode=yes",
    "-o",
    "ConnectTimeout=5",
    REMOTE_HOST,
    `cat ${shellQuote(remotePath)}`
  ])

  let stderr = ""
  child.stderr.on("data", (chunk) => {
    stderr += chunk.toString()
  })

  child.on("close", (code) => {
    if (code !== 0) {
      console.error(`Erreur téléchargement SSH (${code}): ${stderr}`)
    }
  })
  event.node.res.on("close", () => child.kill())
  return sendStream(event, child.stdout)
})