import { Feature } from "#Source/environment/base.index.ts"

import { ensurePermissionGranted } from "./permission.ts"

/**
 * @description Writes the given text to the clipboard. This function ensures
 * that the Clipboard API is available and that the necessary
 * permissions are granted before attempting to write to the clipboard.
 */
export const writeTextToClipboard = async <T extends string>(text: T): Promise<T> => {
  Feature.ensureClipboard()
  await ensurePermissionGranted({ name: "clipboard-write" })

  // write text to clipboard
  await navigator.clipboard.writeText(text)

  return text
}

/**
 * @description Reads text from the clipboard. This function ensures that
 * the Clipboard API is available and that the necessary
 * permissions are granted before attempting to read from the clipboard.
 *
 * It returns the text read from the clipboard as a string.
 */
export const readTextFromClipboard = async (): Promise<string> => {
  Feature.ensureClipboard()
  await ensurePermissionGranted({ name: "clipboard-read" })

  // read text from clipboard
  const text = await navigator.clipboard.readText()

  return text
}

/**
 * @description Writes the given image blob to the clipboard. This function ensures
 * that the Clipboard API is available and that the necessary
 * permissions are granted before attempting to write to the clipboard.
 *
 * It returns the blob that was written to the clipboard.
 */
export const writeBlobImageToClipboard = async <T extends Blob>(blob: T): Promise<T> => {
  Feature.ensureClipboard()
  await ensurePermissionGranted({ name: "clipboard-write" })

  // write image to clipboard
  await navigator.clipboard.write([new ClipboardItem({ [blob.type]: blob })])

  return blob
}

const base64ToBlob = (base64: string): Blob | null => {
  try {
    const byteString = atob(base64.split(",")[1] ?? "")
    const mimeString = base64.split(",")[0]?.split(":")[1]?.split(";")[0]
    if (mimeString === undefined) {
      throw new Error("Invalid MIME type")
    }

    const arrayBuffer = new ArrayBuffer(byteString.length)
    const uintArray = new Uint8Array(arrayBuffer)
    for (let i = 0; i < byteString.length; i = i + 1) {
      const codePoint = byteString.codePointAt(i)
      if (codePoint === undefined) {
        throw new Error("Invalid character in base64 string")
      }
      uintArray[i] = codePoint
    }

    return new Blob([arrayBuffer], { type: mimeString })
  } catch (exception) {
    console.error("Failed to convert base64 to Blob:", exception)
    return null
  }
}
/**
 * @description Writes a base64-encoded image to the clipboard. This function first converts
 * the base64 string to a Blob object and then uses the `writeBlobImageToClipboard`
 * function to write the image to the clipboard.
 *
 * It returns the original base64 string if the operation is successful.
 */
export const writeBase64ImageToClipboard = async <T extends string>(base64: T): Promise<T> => {
  const blob = base64ToBlob(base64)
  if (blob === null) {
    throw new Error("Failed to convert base64 to Blob")
  }
  await writeBlobImageToClipboard(blob)
  return base64
}