PDF_Office/PDF Office/PDF Master/KMClass/KMNPDFPageEdit/KMNThumbnailManager.swift

//
//  KMNThumbnailManager.swift
//  PDF Reader Pro
//
//  Created by 丁林圭 on 2024/10/21.
//

import Cocoa

let kmnThumbnailFolder: String = {
    let documentDirectory = NSSearchPathForDirectoriesInDomains(.documentDirectory, .userDomainMask, true).first!
    return (documentDirectory as NSString).appendingPathComponent("ThumbnailFolder")
}()

public class KMNThumbnail: NSObject {
    var thumbnailDocument:CPDFDocument = CPDFDocument()
    
   typealias KMNThumbnailCompletion = (_ image: NSImage?) -> Void

    var thumbnaiPage:CPDFPage?
    var pageSize:CGSize = CGSizeZero
    var pageIndex:Int = 0
    
    var isHoveBookMark:Bool = false

    public var pageRotate:CGFloat = 0.0 {
        didSet {
            
        }
    }
    
    public init(document: CPDFDocument,currentPageIndex:Int) {
        thumbnailDocument = document
        pageIndex = currentPageIndex
        let page = document.page(at: UInt(currentPageIndex))
        let size =  page?.bounds.size ?? CGSizeZero
        if (page?.rotation ?? 0) % 180 == 0 {
            pageSize = size
        } else {
            pageSize = CGSize(width: size.height, height: size.width)

        }
        thumbnaiPage = page
        pageRotate = 0
        
        isHoveBookMark = document.bookmark(forPageIndex: UInt(pageIndex)) != nil
        
        super.init()
    }
    
    public override init() {
        super.init()
    }
    
    func generateThumImage(completion: KMNThumbnailCompletion?) {
        let filePathID = fileId(for: thumbnailDocument)
        let docsFilePath = kmnThumbnailFolder + "/" + filePathID
        let fileManager = FileManager.default

        if !fileManager.fileExists(atPath: docsFilePath) {
            try? FileManager.default.createDirectory(atPath: docsFilePath, withIntermediateDirectories: true, attributes: nil)
        }
        let imageFilePath = docsFilePath + "/" + (self.thumbnaiPage?.label ?? String(self.pageIndex)) + ".png"
        
        if fileManager.fileExists(atPath: imageFilePath) {
           let image = NSImage.init(contentsOfFile: imageFilePath) ?? NSImage()
            if completion != nil {
                completion!(image)
            }
        } else {
            var thumSize = pageSize
            if pageSize.width < 100 {
                thumSize.width = 100
                thumSize.height *= 100/pageSize.width
            }
            
            thumbnaiPage?.thumbnail(of: thumSize, needReset: true,completion: { pageImage in

                // 将 NSImage 转换为 PNG 数据
                guard let tiffData = pageImage?.tiffRepresentation,
                         let bitmapImage = NSBitmapImageRep(data: tiffData),
                         let pngData = bitmapImage.representation(using: .png, properties: [:]) else {
                       return
                   }

                   do {
                       try pngData.write(to: URL(fileURLWithPath: imageFilePath))
                   } catch {
                   }
                
                if completion != nil {
                    completion!(pageImage)
                }
            });
        }
    }
    
    fileprivate func fileId(for document: CPDFDocument) -> String {
        return "\(document.documentURL.path.hash)"
    }
}

class KMNThumbnailManager: NSObject {
    
    class func clearCacheThumImage() {
        if FileManager.default.fileExists(atPath: kmnThumbnailFolder) {
            try?FileManager.default.removeItem(atPath: kmnThumbnailFolder)
        }

    }
}