import type { CollectionConfig } from 'payload/types'
import type { Readable } from 'stream'
import type { CollectionCachingConfig, PluginOptions, StaticHandler } from './types'
import { createKey } from './utilities/createKey'
import { getStorageClient } from './utilities/getStorageClient'

interface Args {
  collection: CollectionConfig
  cachingOptions?: PluginOptions['uploadCaching']
}

export const getStaticHandler = ({ collection, cachingOptions }: Args): StaticHandler => {
  let maxAge = 86400 // 24 hours default
  let collCacheConfig: CollectionCachingConfig | undefined
  if (cachingOptions !== false) {
    // Set custom maxAge for all collections
    maxAge = cachingOptions?.maxAge || maxAge
    collCacheConfig = cachingOptions?.collections?.[collection.slug] || {}
  }

  // Set maxAge using collection-specific override
  maxAge = collCacheConfig?.maxAge || maxAge

  let cachingEnabled =
    cachingOptions !== false &&
    !!process.env.PAYLOAD_CLOUD_CACHE_KEY &&
    collCacheConfig?.enabled !== false

  return async (req, res, next) => {
    try {
      const { storageClient, identityID } = await getStorageClient()

      const Key = createKey({
        collection: collection.slug,
        filename: req.params.filename,
        identityID,
      })

      const object = await storageClient.getObject({
        Bucket: process.env.PAYLOAD_CLOUD_BUCKET,
        Key,
      })

      res.set({
        'Content-Length': object.ContentLength,
        'Content-Type': object.ContentType,
        ...(cachingEnabled && { 'Cache-Control': `public, max-age=${maxAge}` }),
        ETag: object.ETag,
      })

      if (object?.Body) {
        return (object.Body as Readable).pipe(res)
      }

      return next()
    } catch (err: unknown) {
      req.payload.logger.error({ msg: 'Error getting file from cloud storage', err })
      return next()
    }
  }
}