meta.ts

import type { ImageInfo, ImageCTX } from '../../types/image'

export async function imageMeta(_ctx: ImageCTX, url: string): Promise<ImageInfo> {
  // TODO: Reimplement cache using storage
  // const cache = getCache<ImageInfo>(ctx)

  // const cacheKey = 'image:meta:' + url
  // if (cache.has(cacheKey)) {
  //   return cache.get(cacheKey)
  // }

  const meta = await _imageMeta(url).catch((err) => {
    console.error('Failed to get image meta for ' + url, err + '')
    return {
      width: 0,
      height: 0,
      ratio: 0,
    }
  })

  // cache.set(cacheKey, meta)
  return meta
}

async function _imageMeta(url: string): Promise<ImageInfo> {
  if (import.meta.server) {
    const imageMeta = await import('image-meta').then(r => r.imageMeta)
    const data: Buffer = await fetch(url).then((res: any) => res.buffer())
    const metadata = imageMeta(data)
    if (!metadata) {
      throw new Error(`No metadata could be extracted from the image \`${url}\`.`)
    }
    const { width, height } = metadata
    const meta = {
      width: width!,
      height: height!,
      ratio: width && height ? width / height : undefined,
    }

    return meta
  }
  if (typeof Image === 'undefined') {
    throw new TypeError('Image not supported')
  }

  return new Promise((resolve, reject) => {
    const img = new Image()
    img.onload = () => {
      const meta = {
        width: img.width,
        height: img.height,
        ratio: img.width / img.height,
      }
      resolve(meta)
    }
    img.onerror = err => reject(err)
    img.src = url
  })
}