ModelDownloader.swift

import Foundation

extensionBundle{
vardisplayName:String?{
returnobject(forInfoDictionaryKey: kCFBundleNameKey asString)as?String
}
}

varcacheDirectory:URL{
letparent=FileManager.default.urls(for:.cachesDirectory, in:.userDomainMask)[0]
return parent.appending(path:Bundle.main.bundleIdentifier!)
}

classModelDownloader{
enumState{
case pending
case completed
case failed(Error?)
}

@Publishedvarstate=State.pending

letbaseURL=URL(string:"https://huggingface.co/datasets/ggerganov/whisper.cpp/resolve/main")!

letmodelName:String
letsession:URLSession
letfilename:String
letmodelURL:URL

vartask:URLSessionDownloadTask?

init(modelName:String, configuration:URLSessionConfiguration=.default){
self.modelName = modelName
 session =URLSession(configuration: configuration)
 filename ="\(modelName).bin"
 modelURL = cacheDirectory.appending(path: filename)
}

func resume(){
if !FileManager.default.fileExists(atPath: cacheDirectory.absoluteURL.path){
try!FileManager.default.createDirectory(at: cacheDirectory, withIntermediateDirectories:false)
}

letdestination= modelURL.absoluteURL
ifFileManager.default.fileExists(atPath: destination.path){
 state =.completed
return
}

letrequest=URLRequest(url: baseURL.appending(path: filename))

lettask= session.downloadTask(with: request){[weak self] location, response, error in
iflet error = error {
self?.state =.failed(error)
return
}
iflet location = location {
do{
tryFileManager.default.moveItem(at: location, to: destination)
self?.state =.completed
}catch{
self?.state =.failed(error)
}
}else{
self?.state =.failed(nil)
}
}
 task.resume()
self.task = task
}
}