//
//  KMPDFInsertPreviewViewController.swift
//  PDF Reader Pro
//
//  Created by wanjun on 2022/11/24.
//

import Cocoa

@objc protocol KMPDFInsertPreviewViewControllerDelegate {
    @objc optional func insertPreviewViewController(_ viewController: KMPDFInsertPreviewViewController, pageChanged: Int)
}

class KMPDFInsertPreviewViewController: NSViewController {

    @IBOutlet weak var previewView: CPDFListView!
    @IBOutlet weak var leftTurnBox: KMBox!
    @IBOutlet weak var leftTurnImageView: NSImageView!
    @IBOutlet weak var currentPageNumberTextField: NSTextField!
    @IBOutlet weak var totalPageNumberLabel: NSTextField!
    @IBOutlet weak var rightTurnBox: KMBox!
    @IBOutlet weak var rightTurnImageView: NSImageView!
    
    var pdfDocument: CPDFDocument? = nil
    
    open weak var delete: KMPDFInsertPreviewViewControllerDelegate?
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do view setup here.
        
        previewView.document = pdfDocument
        previewView.autoScales = true
        
        initializeUI()
        initLocalization()
        
        leftTurnBox.downCallback = { [self] (downEntered: Bool, mouseBox: KMBox, event) -> Void in
            if downEntered {
                previousButtonAction(leftTurnBox)
            }
        }
        rightTurnBox.downCallback = { [self] (downEntered: Bool, mouseBox: KMBox, event) -> Void in
            if downEntered {
                nextButtonAction(rightTurnBox)
            }
        }
        
        NotificationCenter.default.addObserver(self, selector: #selector(PDFViewDocumentChangedNotification), name: NSNotification.Name.CPDFViewPageChanged, object: nil)
    }
    
    override func viewDidAppear() {
        super.viewDidAppear()
        
        reloadPDFData()
    }
    
    // MARK: Init
    
    func initializeUI() -> Void {
        
    }
    
    func initLocalization() -> Void {
        leftTurnBox.toolTip = NSLocalizedString("向前", comment: "")
        rightTurnBox.toolTip = NSLocalizedString("向后", comment: "")
    }

    // MARK: private

    func reloadPDFData() -> Void {
        previewView.documentView().documentView?.enclosingScrollView?.hasVerticalScroller = false
        previewView.documentView().documentView?.enclosingScrollView?.hasHorizontalScroller = false
        
        let pageCount = pdfDocument?.pageCount
        let currentPageIndex = pdfDocument?.index(for: previewView.currentPage())
        currentPageNumberTextField.stringValue = String(format: "%ld", (currentPageIndex!+1))
        totalPageNumberLabel.stringValue = String(format: "/ %ld", pageCount!)
        
        self.delete?.insertPreviewViewController?(self, pageChanged: Int(currentPageIndex!+1))
    }
    
    // MARK: Action
    
    @IBAction func nextButtonAction(_ sender: KMBox) -> Void {
        previewView.goToNextPage(nil)
        reloadPDFData()
    }
    
    @IBAction func previousButtonAction(_ sender: KMBox) -> Void {
        previewView.goToPreviousPage(nil)
        reloadPDFData()
    }
    
    // MARK: Notification
    
    @objc func PDFViewDocumentChangedNotification(_ notification: Notification) -> Void {
        let page = previewView.currentPage()
        let pageIndex = previewView.document.index(for: page)
        currentPageNumberTextField.stringValue = String(format: "%ld", (pageIndex + 1))
    }
}

extension KMPDFInsertPreviewViewController: NSTextFieldDelegate {
    func controlTextDidChange(_ obj: Notification) {
        
    }
    
    func controlTextDidEndEditing(_ obj: Notification) {
        let textField = obj.object as! NSTextField
        if textField.isEqual(currentPageNumberTextField) {
            let index = Int(currentPageNumberTextField.stringValue)
            let pageCount = pdfDocument?.pageCount
            let currentPageIndex = pdfDocument?.index(for: previewView.currentPage())
            if index! > 0 && index! <= pageCount! {
                let gotoPage = pdfDocument?.page(at: UInt(index! - 1))
                previewView.go(toPageIndex: Int((pdfDocument?.index(for: gotoPage))!), animated: true)
                reloadPDFData()
            } else {
                currentPageNumberTextField.stringValue = String(format: "%ld", (currentPageIndex!+1))
            }
        }
    }
}