//
//  KMBGTemplateController.swift
//  PDF Reader Pro
//
//  Created by Niehaoyu on 2024/11/7.
//

import Cocoa
import KMComponentLibrary

@objc protocol KMBGTemplateControllerDelegate: AnyObject {
    
    @objc optional func templateControllerDidAddData(_ controller: KMBGTemplateController)
    
    @objc optional func templateControllerDidEditData(_ controller: KMBGTemplateController, _ data: KMBackgroundModel)
 
    //选中内容切换
    @objc optional func templateControllerDidSelectedChanged(_ controller: KMBGTemplateController)
    
}

class KMBGTemplateController: NSViewController {
  
    @IBOutlet var contendView: NSView!
    @IBOutlet var titleLabel: NSTextField!
    @IBOutlet var addButton: ComponentButton!
    
    @IBOutlet var emptyView: ComponentEmpty!
    
    @IBOutlet var scrollView: NSScrollView!
    @IBOutlet var collectionView: NSCollectionView!
    
    weak open var delegate: KMBGTemplateControllerDelegate?

    var selectedBackground: KMBackgroundModel?
    
    override func viewDidLoad() {
        super.viewDidLoad()
        // Do view setup here.
        
        configUI()
     
        setupProperty()
        
        reloadData()
    }
    
    func setupProperty() {
        
        addButton.properties = ComponentButtonProperty(type: .text_gray, size: .xxs, onlyIcon: true, icon: NSImage(named: "watermark_template_add"), keepPressState: false)
        addButton.setTarget(self, action: #selector(buttonClicked(_:)))
        
        emptyView.properties = ComponentEmptyProperty(emptyType: .noWatermark, text: KMLocalizedString("No Template"), subText: KMLocalizedString("Here is the description."))
    }
      
    func configUI() {
        
        view.wantsLayer = true
        view.layer?.backgroundColor = ComponentLibrary.shared.getComponentColorFromKey("colorBg/layout-middle").cgColor
         
        titleLabel.stringValue = KMLocalizedString("Templates")
        titleLabel.textColor = ComponentLibrary.shared.getComponentColorFromKey("colorText/2")
        titleLabel.font = ComponentLibrary.shared.getFontFromKey("mac/body-m-bold")
         
        collectionView.backgroundColors = [NSColor.clear]
        collectionView.wantsLayer = true
        collectionView.layer?.backgroundColor = NSColor.clear.cgColor
        collectionView.delegate = self
        collectionView.dataSource = self
        collectionView.allowsEmptySelection = false
        collectionView.allowsMultipleSelection = false
        
        collectionView.register(KMBGTemplateItem.self, forItemWithIdentifier: NSUserInterfaceItemIdentifier(rawValue: "KMBGTemplateItem"))
     }
    
    //刷新所有数据
    public func reloadData() {
        if KMBackgroundManager.defaultManager.datas.count == 0 {
            collectionView.isHidden = true
            
            emptyView.isHidden = false
        } else {
            emptyView.isHidden = true
            
            collectionView.isHidden = false
            collectionView.reloadData()
            
            updateSelectedState()
        }
    }
    
    func updateSelectedState() {
        if let selData = selectedBackground {
            if let index = KMBackgroundManager.defaultManager.datas.firstIndex(of: selData) {
                
                let indexpath = IndexPath(item: index, section: 0)
                var set = Set<IndexPath>()
                set.insert(indexpath)
                
                collectionView.selectItems(at: set, scrollPosition: .top)
            }
        } else {
            collectionView.deselectAll(nil)
        }
    }
     
    private func collectionViewSelectedChanged() {
        let indexs = collectionView.selectionIndexPaths
        
        if indexs.count > 0 {
            for index in indexs {
                let data = KMBackgroundManager.defaultManager.datas[index.item]
                selectedBackground = data
            }
        } else {
            selectedBackground = nil
        }
        
        delegate?.templateControllerDidSelectedChanged?(self)
    }
    
    //MARK: - action
    @objc func buttonClicked(_ sender: ComponentButton) {
        if sender == addButton {
            if selectedBackground != nil {
                selectedBackground = nil
                reloadData()
                delegate?.templateControllerDidSelectedChanged?(self)
            }
            
            delegate?.templateControllerDidAddData?(self)
        }
    }
}

//MARK: - NSCollectionViewDelegate, NSCollectionViewDataSource
extension KMBGTemplateController: NSCollectionViewDelegate, NSCollectionViewDataSource, NSCollectionViewDelegateFlowLayout {
    
    public func collectionView(_ collectionView: NSCollectionView, numberOfItemsInSection section: Int) -> Int {
        return KMBackgroundManager.defaultManager.datas.count
    }
     
    public func collectionView(_ collectionView: NSCollectionView, itemForRepresentedObjectAt indexPath: IndexPath) -> NSCollectionViewItem {
        if indexPath.item >= KMBackgroundManager.defaultManager.datas.count {
            return NSCollectionViewItem()
        }
        
        let item: KMBGTemplateItem = collectionView.makeItem(withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "KMBGTemplateItem"), for: indexPath) as! KMBGTemplateItem
        item.delegate = self
        item.backgroundModel = KMBackgroundManager.defaultManager.datas[indexPath.item]
        if let selData = selectedBackground {
            if item.backgroundModel == selData {
                item.isSelected = true
            }
        }
        item.reloadData()
        return item
    }
    
    public func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> NSSize {

        return CGSize(width: 168, height: 237)
    }
     
    func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
        return 8
    }
    
    func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
        return 8
    }
    
    func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, insetForSectionAt section: Int) -> NSEdgeInsets {
        return NSEdgeInsets(top: 8, left: 0, bottom: 8, right: 0)
    }
    
    public func collectionView(_ collectionView: NSCollectionView, didSelectItemsAt indexPaths: Set<IndexPath>) {
        collectionViewSelectedChanged()
    }
    
    public func collectionView(_ collectionView: NSCollectionView, didDeselectItemsAt indexPaths: Set<IndexPath>) {
        collectionViewSelectedChanged()
    }
    
}

//MARK: - kmNWatermarkTemplateItemDelegate
extension KMBGTemplateController: KMBGTemplateItemDelegate {
    func kmNBGTemplateItemDidEdit(_ view: KMBGTemplateItem) {
        if let data = view.backgroundModel {
            delegate?.templateControllerDidEditData?(self, data)
        }
    }
    
    func kmNBGTemplateItemDidDelete(_ view: KMBGTemplateItem) {
        if let data = view.backgroundModel {
            let alert = NSAlert()
            alert.alertStyle = .critical
            alert.messageText = String(format: KMLocalizedString("Are you sure you want to remove the background?"))
            alert.addButton(withTitle: KMLocalizedString("Delete"))
            alert.addButton(withTitle: KMLocalizedString("Cancel"))
            
            alert.beginSheetModal(for: NSApp.mainWindow!) { (response) in
                if response == .alertFirstButtonReturn {
                    let _ = KMBackgroundManager.defaultManager.deleteTemplate(model: data)
                    if data == self.selectedBackground {
                        self.selectedBackground = nil
                        
                        self.delegate?.templateControllerDidSelectedChanged?(self)
                    }
                    self.reloadData()
                }
            }
        }
    }
    
//    func kmNBGTemplateItemDidUpdateSelectedState(_ view: KMBGTemplateItem) {
//        if view.itemSelected {
//            selectedBackground = view.backgroundModel
//        } else {
//            selectedBackground = nil
//        }
//        
//        collectionViewSelectedChanged()
//    }
}