import UIKit
import PDFKit
import SVProgressHUD

class PdfViewController: UIViewController {
    
    @IBOutlet weak var dummyPdfView: UIView!
    
    @IBOutlet weak var courseLAbel: UILabel!
    
    var pdfView : PDFView!
    
    var pdfString = ""
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        setPDF()
    }
    
    func setPDF() {
        
        SVProgressHUD.show(withStatus: "Loading...")

        DispatchQueue.global(qos: .background).async {
            if let pdfURL = URL(string: self.pdfString), let pdfDocument = PDFDocument(url: pdfURL) {
                DispatchQueue.main.async {
                    // Create and configure the PDFView on the main thread
                    let newPDFView = PDFView(frame: self.dummyPdfView.bounds)
                    newPDFView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
                    self.dummyPdfView.addSubview(newPDFView)
                    
                    // Set properties and assign document to PDFView
                    newPDFView.autoScales = true
                    newPDFView.displayDirection = .vertical
                    newPDFView.displayMode = .singlePageContinuous
                    newPDFView.document = pdfDocument
                    
                    SVProgressHUD.dismiss()
                }
            } else {
                DispatchQueue.main.async {
                    SVProgressHUD.showError(withStatus: "Failed to load PDF")
                }
            }
        }
    }
    
    @IBAction func backButtonPressed(_ sender: Any) {
        SVProgressHUD.dismiss()
        self.dismiss(animated: true)
    }
}