Add documentation

This commit is contained in:
toasted-nutbread 2020-04-19 10:24:59 -04:00
parent 0e80c0d5d0
commit a7e7d546c7

View File

@ -15,12 +15,28 @@
* along with this program. If not, see <https://www.gnu.org/licenses/>. * along with this program. If not, see <https://www.gnu.org/licenses/>.
*/ */
/**
* mediaUtility is an object containing helper methods related to media processing.
*/
const mediaUtility = (() => { const mediaUtility = (() => {
/**
* Gets the file extension of a file path. URL search queries and hash
* fragments are not handled.
* @param path The path to the file.
* @returns The file extension, including the '.', or an empty string
* if there is no file extension.
*/
function getFileNameExtension(path) { function getFileNameExtension(path) {
const match = /\.[^./\\]*$/.exec(path); const match = /\.[^./\\]*$/.exec(path);
return match !== null ? match[0] : ''; return match !== null ? match[0] : '';
} }
/**
* Gets an image file's media type using a file path.
* @param path The path to the file.
* @returns The media type string if it can be determined from the file path,
* otherwise null.
*/
function getImageMediaTypeFromFileName(path) { function getImageMediaTypeFromFileName(path) {
switch (getFileNameExtension(path).toLowerCase()) { switch (getFileNameExtension(path).toLowerCase()) {
case '.apng': case '.apng':
@ -52,6 +68,13 @@ const mediaUtility = (() => {
} }
} }
/**
* Attempts to load an image using a base64 encoded content and a media type.
* @param mediaType The media type for the image content.
* @param content The binary content for the image, encoded in base64.
* @returns A Promise which resolves with an HTMLImageElement instance on
* successful load, otherwise an error is thrown.
*/
function loadImageBase64(mediaType, content) { function loadImageBase64(mediaType, content) {
return new Promise((resolve, reject) => { return new Promise((resolve, reject) => {
const image = new Image(); const image = new Image();