require("svelte/register")

const send = require("koa-send")
const { resolve, join } = require("../../../utilities/centralPath")
const fetch = require("node-fetch")
const fs = require("fs-extra")
const uuid = require("uuid")
const AWS = require("aws-sdk")
const { prepareUpload } = require("../deploy/utils")
const { stringTemplate } = require("../../../utilities/stringTemplating")
const {
  budibaseAppsDir,
  budibaseTempDir,
} = require("../../../utilities/budibaseDir")
const CouchDB = require("../../../db")
const setBuilderToken = require("../../../utilities/builder/setBuilderToken")
const fileProcessor = require("../../../utilities/fileProcessor")
const env = require("../../../environment")

function objectStoreUrl() {
  if (env.SELF_HOSTED) {
    // can use a relative url for this as all goes through the proxy (this is hosted in minio)
    return `/app-assets/assets`
  } else {
    return "https://cdn.app.budi.live/assets"
  }
}

// this was the version before we started versioning the component library
const COMP_LIB_BASE_APP_VERSION = "0.2.5"

exports.serveBuilder = async function(ctx) {
  let builderPath = resolve(__dirname, "../../../../builder")
  if (ctx.file === "index.html") {
    await setBuilderToken(ctx)
  }
  await send(ctx, ctx.file, { root: ctx.devPath || builderPath })
}

exports.uploadFile = async function(ctx) {
  let files
  files =
    ctx.request.files.file.length > 1
      ? Array.from(ctx.request.files.file)
      : [ctx.request.files.file]

  const attachmentsPath = resolve(
    budibaseAppsDir(),
    ctx.user.appId,
    "attachments"
  )

  if (env.CLOUD) {
    // remote upload
    const s3 = new AWS.S3({
      params: {
        Bucket: "prod-budi-app-assets",
      },
    })

    const uploads = files.map(file => {
      const fileExtension = [...file.name.split(".")].pop()
      const processedFileName = `${uuid.v4()}.${fileExtension}`

      return prepareUpload({
        file,
        s3Key: `assets/${ctx.user.appId}/attachments/${processedFileName}`,
        s3,
      })
    })

    ctx.body = await Promise.all(uploads)
    return
  }

  ctx.body = await processLocalFileUploads({
    files,
    outputPath: attachmentsPath,
    appId: ctx.user.appId,
  })
}

async function processLocalFileUploads({ files, outputPath, appId }) {
  // create attachments dir if it doesnt exist
  !fs.existsSync(outputPath) && fs.mkdirSync(outputPath, { recursive: true })

  const filesToProcess = files.map(file => {
    const fileExtension = [...file.name.split(".")].pop()
    // filenames converted to UUIDs so they are unique
    const processedFileName = `${uuid.v4()}.${fileExtension}`

    return {
      name: file.name,
      path: file.path,
      size: file.size,
      type: file.type,
      processedFileName,
      extension: fileExtension,
      outputPath: join(outputPath, processedFileName),
      url: join("/attachments", processedFileName),
    }
  })

  const fileProcessOperations = filesToProcess.map(fileProcessor.process)

  const processedFiles = await Promise.all(fileProcessOperations)

  let pendingFileUploads
  // local document used to track which files need to be uploaded
  // db.get throws an error if the document doesn't exist
  // need to use a promise to default
  const db = new CouchDB(appId)
  await db
    .get("_local/fileuploads")
    .then(data => {
      pendingFileUploads = data
    })
    .catch(() => {
      pendingFileUploads = { _id: "_local/fileuploads", uploads: [] }
    })

  pendingFileUploads.uploads = [
    ...processedFiles,
    ...pendingFileUploads.uploads,
  ]
  await db.put(pendingFileUploads)

  return processedFiles
}

exports.performLocalFileProcessing = async function(ctx) {
  const { files } = ctx.request.body

  const processedFileOutputPath = resolve(
    budibaseAppsDir(),
    ctx.user.appId,
    "attachments"
  )

  try {
    ctx.body = await processLocalFileUploads({
      files,
      outputPath: processedFileOutputPath,
      appId: ctx.user.appId,
    })
  } catch (err) {
    ctx.throw(500, err)
  }
}

exports.serveApp = async function(ctx) {
  const App = require("./templates/BudibaseApp.svelte").default
  const db = new CouchDB(ctx.params.appId)
  const appInfo = await db.get(ctx.params.appId)

  const { head, html, css } = App.render({
    title: appInfo.name,
    production: env.CLOUD,
    appId: ctx.params.appId,
    objectStoreUrl: objectStoreUrl(),
  })

  const appHbs = fs.readFileSync(`${__dirname}/templates/app.hbs`, "utf8")
  ctx.body = stringTemplate(appHbs, {
    head,
    body: html,
    style: css.code,
    appId: ctx.params.appId,
  })
}

exports.serveAttachment = async function(ctx) {
  const appId = ctx.user.appId
  const attachmentsPath = resolve(budibaseAppsDir(), appId, "attachments")

  // Serve from CloudFront
  // TODO: need to replace this with link to self hosted object store
  if (env.CLOUD) {
    const S3_URL = join(objectStoreUrl(), appId, "attachments", ctx.file)
    const response = await fetch(S3_URL)
    const body = await response.text()
    ctx.set("Content-Type", response.headers.get("Content-Type"))
    ctx.body = body
    return
  }

  await send(ctx, ctx.file, { root: attachmentsPath })
}

exports.serveAppAsset = async function(ctx) {
  // default to homedir
  const appPath = resolve(budibaseAppsDir(), ctx.user.appId, "public")

  await send(ctx, ctx.file, { root: ctx.devPath || appPath })
}

exports.serveComponentLibrary = async function(ctx) {
  const appId = ctx.query.appId || ctx.appId
  // default to homedir
  let componentLibraryPath = resolve(
    budibaseAppsDir(),
    appId,
    "node_modules",
    decodeURI(ctx.query.library),
    "package",
    "dist"
  )

  if (ctx.isDev) {
    componentLibraryPath = join(
      budibaseTempDir(),
      decodeURI(ctx.query.library),
      "dist"
    )
  }

  if (env.CLOUD) {
    let componentLib = "componentlibrary"
    if (ctx.user.version) {
      componentLib += `-${ctx.user.version}`
    } else {
      componentLib += `-${COMP_LIB_BASE_APP_VERSION}`
    }
    const S3_URL = encodeURI(
      join(
        objectStoreUrl(appId),
        componentLib,
        ctx.query.library,
        "dist",
        "index.js"
      )
    )
    const response = await fetch(S3_URL)
    const body = await response.text()
    ctx.type = "application/javascript"
    ctx.body = body
    return
  }

  await send(ctx, "/awsDeploy.js", { root: componentLibraryPath })
}