//
//  KMPDFThumbnialPageView.swift
//  PDF Master
//
//  Created by tangchao on 2022/11/24.
//

import Cocoa

extension CPDFPage {
    private static var _pageEditImageKey = "KMPageEditImageKey"
    var pageEditImage: NSImage? {
        get {
            return objc_getAssociatedObject(self, &CPDFPage._pageEditImageKey) as? NSImage
        }
        set {
            objc_setAssociatedObject(self, &CPDFPage._pageEditImageKey, newValue, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
    }
}

class KMPDFThumbnialPageLayer: CATiledLayer {
    var page: CPDFPage?
    
    override init() {
        super.init()
        
        self.initDefaultValue()
    }
    
    required init?(coder: NSCoder) {
        super.init(coder: coder)
        
        self.initDefaultValue()
    }
    
    public func initDefaultValue() {
        self.levelsOfDetail = 2
        self.levelsOfDetailBias = 3
        self.tileSize = CGSize(width: 1024, height: 1024)
    }
    
    override func draw(in ctx: CGContext) {
        super.draw(in: ctx)
        
        if (self.page != nil) {
//            if let data = self.page?.pageEditImage {
//                ctx.saveGState()
//                var bounds = self.page!.bounds
//                let transform = self.page!.transform()
//                bounds = bounds.applying(transform);
//
//                let viewWidth: CGFloat = NSWidth(self.bounds)
//                let viewHeight: CGFloat = NSHeight(self.bounds)
//
//                if (self.page!.rotation == -90 || self.page!.rotation == -270) {
//                    let height = bounds.size.height
//                    bounds.size.height = bounds.size.width
//                    bounds.size.width = height
//                }
//
//                ctx.scaleBy(x: viewWidth / bounds.size.width,
//                            y: viewHeight / bounds.size.height);
//                let bitmap = NSBitmapImageRep(data: data.tiffRepresentation!)
//                ctx.draw((bitmap?.cgImage)!, in: NSMakeRect(0, 0, viewWidth, viewHeight))
//                ctx.restoreGState()
//                self.contents = bitmap?.cgImage
//            } else {
                ctx.saveGState();
                
                var bounds = self.page!.bounds
                let transform = self.page!.transform()
                bounds = bounds.applying(transform);
                
                let viewWidth: CGFloat = NSWidth(self.bounds)
                let viewHeight: CGFloat = NSHeight(self.bounds)
                
                if (self.page!.rotation == -90 || self.page!.rotation == -270) {
                    let height = bounds.size.height
                    bounds.size.height = bounds.size.width
                    bounds.size.width = height
                }
                
                ctx.scaleBy(x: viewWidth / bounds.size.width,
                            y: viewHeight / bounds.size.height);
                self.page!.drawEdit(with: .cropBox, to: ctx)
                ctx.restoreGState();
                
                if let _image = ctx.makeImage() {
                    let image = NSImage(cgImage: _image, size: NSSize(width: viewWidth, height: viewHeight))
                    self.page?.pageEditImage = image
                }
//            }
        }
    }
}

class KMPDFThumbnialPageView: NSView {
    internal var _page: CPDFPage?
    var page: CPDFPage? {
        get {
            self._page
        }
        set {
            self._page = newValue
            
            if pageLayer != nil {
                pageLayer.contents = nil
                pageLayer.delegate = nil
                pageLayer.removeFromSuperlayer()
            }
            
            pageLayer = KMPDFThumbnialPageLayer()
            pageLayer.frame = self.bounds
            pageLayer.page = newValue
            self.layer?.addSublayer(pageLayer)
            
//            if let image = self._page?.pageEditImage {
//                if (self.pageImageIv.superview == nil) {
//                    self.addSubview(self.pageImageIv)
//                }
//                self.pageImageIv.image = image
//                self.pageImageIv.imageScaling = .scaleAxesIndependently
//                self.pageImageIv.translatesAutoresizingMaskIntoConstraints = false
//                self.pageImageIv.frame = self.bounds
//                self.pageImageIv.isHidden = false
////                self.pageImageIv.image = image
//            } else {
//                self.pageImageIv.isHidden = true
//            }
        }
    }
    
    var pageLayer: KMPDFThumbnialPageLayer!
    var pageImageIv = NSImageView()
    
    override init(frame frameRect: NSRect) {
        super.init(frame: frameRect)
        
        self.wantsLayer = true
        self.layer?.backgroundColor = NSColor.white.cgColor
        
        self.shadow = NSShadow()
        self.layer?.shadowColor = NSColor.black.cgColor
        self.layer?.shadowOpacity = 0.2
        self.layer?.shadowRadius = 3
        self.layer?.shadowOffset = CGSize(width: 0, height: -3)
        
        if (pageLayer != nil) {
            pageLayer.frame = self.bounds
        }
        self.pageImageIv.frame = self.bounds
    }
    
    required init?(coder: NSCoder) {
        super.init(coder: coder)
    }
    
    override func layout() {
        super.layout()
        
        if (pageLayer != nil) {
            pageLayer.frame = self.bounds
            pageLayer.setNeedsDisplay()
        }
        self.pageImageIv.frame = self.bounds
    }
    
}