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

import Cocoa

@objc protocol KMNThumbnailBaseViewDelegate: AnyObject {
    @objc optional func clickThumbnailViewControlle(pageEditVC:KMNThumbnailBaseViewController?,currentIndex:Int)
    
    @objc optional func insertPDFThumbnailViewControlle(pageEditVC:KMNThumbnailBaseViewController?,pdfDocment:CPDFDocument?)
}

internal let kmnThumLocalForDraggedTypes = NSPasteboard.PasteboardType(rawValue: "kmnThumLocalForDraggedTypes")

class KMNThumbnailBaseViewController: KMNBaseViewController,NSCollectionViewDelegate, NSCollectionViewDataSource,NSCollectionViewDelegateFlowLayout {
    
    weak open var thumbnailBaseViewDelegate: KMNThumbnailBaseViewDelegate?
    
    @IBOutlet var backViewBox: NSBox!
    @IBOutlet var collectionView: KMNThumbnailCollectionView!
    
    let subTitleHeight: CGFloat = 20.0
    
    let maxCellHeight: CGFloat = 280.0
    
    private var currentDocument:CPDFDocument?
    
    public var currentUndoManager:UndoManager?
    
    public var showDocument: CPDFDocument? {
        return currentDocument
    }
    private var thumbnails:[KMNThumbnail] = []
    
    var selectionIndexPaths: Set<IndexPath> = [] {
        didSet {
            var indexpaths: Set<IndexPath> = []
            for indexpath in selectionIndexPaths {
                if (indexpath.section >= collectionView.numberOfSections) {
                    continue
                }
                if indexpath.section < 0 {
                    continue
                }
                if (indexpath.item >= collectionView.numberOfItems(inSection: indexpath.section)) {
                    continue
                }
                if indexpath.item < 0 {
                    continue
                }
                
                indexpaths.insert(indexpath)
            }
            
            collectionView.selectionIndexPaths = indexpaths
            collectionView.scrollToItems(at: indexpaths, scrollPosition: .top)
        }
    }
    
    public var clickPageIndex: Int{
        let minIndexPath = selectionIndexPaths.min(by: { $0.item < $1.item })
        return minIndexPath?.item ?? 0
    }
    
    public var isAdjustWidth:Bool = false
        
    public var isShowPageSize:Bool = false {
        didSet {
            if oldValue != isShowPageSize {
                var pageSize = pageThumbnailSize
                if(isShowPageSize) {
                    pageSize.height += subTitleHeight
                } else {
                    pageSize.height -= subTitleHeight

                }
                pageThumbnailSize = pageSize
                collectionView.reloadData()
            }
        }
    }
    
    public var pageThumbnailSize:CGSize = CGSizeMake(185.0, 260) {
        didSet {
            collectionView.reloadData()
        }
    }
    public let defaultItemSize = NSMakeSize(185.0, 260)
    
    var dragLocalityPages: [CPDFPage] = []
    
    deinit {
        thumbnailBaseViewDelegate = nil
        KMPrint("KMNThumbnailBaseViewController deinit.")
    }
    
    init(_ document: CPDFDocument?) {
        super.init(nibName: "KMNThumbnailBaseViewController", bundle: nil)
        currentDocument = document
    }
    
    init(_ filePath: String,password:String?) {
        super.init(nibName: "KMNThumbnailBaseViewController", bundle: nil)
        let document = CPDFDocument.init(url: URL(fileURLWithPath: filePath))
        if password != nil {
            document?.unlock(withPassword: password as String?)
        }
        
        if document?.allowsCopying == false || document?.allowsPrinting == false {
            self.exitCurrentView()
        } else {
            currentDocument = document
        }
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        collectionView.delegate = self
        collectionView.dataSource = self
        collectionView.isSelectable = true //支持拖拽需设置未True
        collectionView.allowsMultipleSelection = true
        
        collectionView.register(KMNThumbnailCollectionViewItem.self, forItemWithIdentifier: NSUserInterfaceItemIdentifier(rawValue: "thumbnailCollectionViewItem"))
        
        collectionView.registerForDraggedTypes([.fileURL])
        collectionView.setDraggingSourceOperationMask(.every, forLocal: false)
        collectionView.setDraggingSourceOperationMask(.every, forLocal: true)

        refreshDatas()
    }
    
    public func exitCurrentView() {
        thumbnailBaseViewDelegate?.clickThumbnailViewControlle?(pageEditVC: self, currentIndex: clickPageIndex)
    }
    
    public func supportDragFileTypes()->[String] {
        let supportFiles = KMNConvertTool.pdfExtensions + KMConvertPDFManager.supportFileType()

        return supportFiles
    }
    
    public func refreshDatas() {
        thumbnails = []
        if currentDocument != nil {
            for i in 0 ... currentDocument!.pageCount {
                let thumbnail = KMNThumbnail.init(document: currentDocument!, currentPageIndex: Int(i))
                thumbnails.append(thumbnail)
            }
        }
    }

    // MARK: - NSCollectionViewDataSource
    func collectionView(_ collectionView: NSCollectionView, numberOfItemsInSection section: Int) -> Int {
        return thumbnails.count
    }
    
    func collectionView(_ collectionView: NSCollectionView, itemForRepresentedObjectAt indexPath: IndexPath) -> NSCollectionViewItem {
        let item: KMNThumbnailCollectionViewItem = collectionView.makeItem(withIdentifier: NSUserInterfaceItemIdentifier(rawValue: "thumbnailCollectionViewItem"), for: indexPath) as! KMNThumbnailCollectionViewItem
        item.isShowFileSize = isShowPageSize
        item.doubleClickBack = { [weak self] in
            self?.thumbnailBaseViewDelegate?.clickThumbnailViewControlle?(pageEditVC: self, currentIndex: indexPath.item)
        }

        item.thumbnailMode = thumbnails[indexPath.item]
        return item
    }
    
    
    // MARK: - NSCollectionViewDelegateFlowLayout
    
    func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> NSSize {
        if isAdjustWidth == false {
            return pageThumbnailSize
        } else {
            let thumbnailMode: KMNThumbnail = thumbnails[indexPath.item]
            let pageSize = thumbnailMode.pageSize
            
            var cellHeight = pageSize.width / ((pageThumbnailSize.width - 32) * pageThumbnailSize.height)
            var cellWidth = pageThumbnailSize.width
            if cellHeight > maxCellHeight {
                cellHeight = 280.0
                cellWidth = cellHeight/pageSize.height * pageSize.width
            }
            
            return CGSize(width: cellWidth, height: cellHeight)
        }
    }
    
    func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, minimumLineSpacingForSectionAt section: Int) -> CGFloat {
        return 16.0
    }
    
    func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, minimumInteritemSpacingForSectionAt section: Int) -> CGFloat {
        return 24.0
    }
    
    public func collectionView(_ collectionView: NSCollectionView, layout collectionViewLayout: NSCollectionViewLayout, insetForSectionAt section: Int) -> NSEdgeInsets {
        return NSEdgeInsetsMake(24.0, 24.0, 24.0, 24.0)
    }
    
    //MARK: - NSCollectionViewDelegate
    func collectionView(_ collectionView: NSCollectionView,
                        writeItemsAt indexPaths: Set<IndexPath>,
                        to pasteboard: NSPasteboard) -> Bool {
        if IAPProductsManager.default().isAvailableAllFunction() == false {
            return false
        }
        
        var docmentName = currentDocument?.documentURL.lastPathComponent.deletingPathExtension ?? ""
        let pagesName = indexPaths.count > 1 ? " pages" : " page"
        var tFileName = pagesName + KMNTools.parseIndexPathsSet(indexSets: collectionView.selectionIndexPaths)
        if tFileName.count > 50 {
            tFileName = String(tFileName.prefix(50))
        }
        
        pasteboard.declareTypes([.fileURL], owner: self)
        let writePDFDocument = CPDFDocument()
        
        for indexPath in indexPaths {
            let row = indexPath.item
            if let copyPage = currentDocument?.page(at: UInt(row)) as? CPDFPage {
                writePDFDocument?.insertPageObject(copyPage, at: writePDFDocument?.pageCount ?? 0)
            }
        }
        
        var cachesDir = FileManager.default.urls(for: .cachesDirectory, in: .userDomainMask).first!
        cachesDir =  cachesDir.appendingPathComponent("PageEdit_Pasteboard")
        let fileManager = FileManager.default
        if !fileManager.fileExists(atPath: cachesDir.path) {
            try? FileManager.default.createDirectory(atPath: cachesDir.path, withIntermediateDirectories: true, attributes: nil)
        }
        docmentName = "\(docmentName)\(tFileName)"
        if docmentName.count > 50 {
            docmentName = String(docmentName.prefix(50))
        }
        
        let filePathURL = cachesDir.appendingPathComponent(docmentName).appendingPathExtension("pdf")
        let success = writePDFDocument?.write(to: filePathURL, isSaveFontSubset:false)
        if success == true {
            pasteboard.setPropertyList([filePathURL.path], forType: .fileURL)
            return true
        } else {
            return false
        }
    }
    
    func collectionView(_ collectionView: NSCollectionView,
                        draggingSession session: NSDraggingSession,
                        willBeginAt screenPoint: NSPoint,
                        forItemsAt indexPaths: Set<IndexPath>) {
        let sortedIndexPaths = indexPaths.sorted { (ip1, ip2) -> Bool in
            if ip1.section == ip2.section {
                return ip1.item < ip2.item
            }
            return ip1.section < ip2.section
        }
        dragLocalityPages = []
        for fromIndexPath in sortedIndexPaths {
            let page = thumbnails[fromIndexPath.item].thumbnaiPage
            if(page != nil) {
                dragLocalityPages.append(page!)
            }
        }
    }

    func collectionView(_ collectionView: NSCollectionView, validateDrop draggingInfo: NSDraggingInfo, proposedIndexPath proposedDropIndexPath: AutoreleasingUnsafeMutablePointer<NSIndexPath>, dropOperation proposedDropOperation: UnsafeMutablePointer<NSCollectionView.DropOperation>) -> NSDragOperation {
        let pboard = draggingInfo.draggingPasteboard
        
        if dragLocalityPages.count != 0 {
            if proposedDropOperation.pointee == .on {
                proposedDropOperation.pointee = .before
            }
            return .move
        } else if let availableType = pboard.availableType(from: [.fileURL]), availableType == .fileURL {
            if let fileNames = pboard.propertyList(forType: .fileURL) as? [String], fileNames.count >= 1 {
                let path = fileNames.first!
                let pathExtension = URL(fileURLWithPath: path).pathExtension.lowercased()
                if pathExtension == "pdf" || supportDragFileTypes().contains(pathExtension) {
                    return .copy
                }
            }
        }
        return []
    }

    func collectionView(_ collectionView: NSCollectionView,
                        acceptDrop draggingInfo: NSDraggingInfo,
                        indexPath: IndexPath,
                        dropOperation: NSCollectionView.DropOperation) -> Bool {
        let pboard = draggingInfo.draggingPasteboard
        if dragLocalityPages.count != 0 {
            movePages(pages: dragLocalityPages, destinationDex: indexPath.item)
            return true
        } else if let availableType = pboard.availableType(from: [.fileURL]), availableType == .fileURL {
            let index = indexPath.item
            
            if let fileNames = pboard.propertyList(forType: .fileURL) as? [String] {
                insertFromFilePath(fileNames: fileNames, formDex: 0, indexDex: UInt(index), selectIndexs: []) { zSelectIndexs in
                    self.refreshDatas()
                    self.selectPages(with: zSelectIndexs)
                }
                
                return true
            }
        }
        return false
    }

    func collectionView(_ collectionView: NSCollectionView,
                        draggingSession session: NSDraggingSession,
                        endedAt screenPoint: NSPoint,
                        dragOperation operation: NSDragOperation) {
        dragLocalityPages = []
    }

}