exports.blurOffensiveImages = functions.storage.object().onChange(event => {
    const object = event.data;
    console.log(event)

    // Exit if this is a move or deletion event.
    if (object.resourceState === 'not_exists') {
      return -1
    }

    if (event.data.metadata.isModerateOperation) {
        console.log("Side-effect")
        return -1
    }

    // Check the image content using the Cloud Vision API.
    return visionClient.safeSearchDetection(`gs://happyin-8708e.appspot.com/${object.name}`).then(data => {
      const { adult, violence } = data[0].safeSearchAnnotation;
      console.log("Flags: ", adult, violence)

      const _flags = ["VERY_UNLIKELY", "UNLIKELY", "POSSIBLE", "LIKELY", "VERY_LIKELY"]

      if (_flags.includes(adult) || _flags.includes(violence)) {
         let _moderatedImage = admin.storage().bucket().file('/assets/forbidden-photo.jpg')
         console.log("Copying to: " + object.name)
         return _moderatedImage.copy({
            destination: `gs://happyin-8708e.appspot.com/${object.name}`,
            metadata: {
                isModerateOperation: true
            }
        })
      }
      else
        return true
    })
})