//
//  NCOperationQueue.swift
//  Nextcloud
//
//  Created by Marino Faggiana on 03/06/2020.
//  Copyright © 2020 Marino Faggiana. All rights reserved.
//
//  Author Marino Faggiana <marino.faggiana@nextcloud.com>
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
//


import Foundation
import Queuer
import NCCommunication

@objc class NCOperationQueue: NSObject {
    @objc public static let shared: NCOperationQueue = {
        let instance = NCOperationQueue()
        return instance
    }()
    
    private var downloadQueue = Queuer(name: "downloadQueue", maxConcurrentOperationCount: 5, qualityOfService: .default)
    private let readFolderSyncQueue = Queuer(name: "readFolderSyncQueue", maxConcurrentOperationCount: 1, qualityOfService: .default)
    private let downloadThumbnailQueue = Queuer(name: "downloadThumbnailQueue", maxConcurrentOperationCount: 10, qualityOfService: .default)
    
    // Download file
    @objc func download(metadata: tableMetadata, selector: String, setFavorite: Bool) {
        downloadQueue.addOperation(NCOperationDownload.init(metadata: metadata, selector: selector, setFavorite: setFavorite))
    }
    @objc func downloadCancelAll() {
        downloadQueue.cancelAll()
    }
    @objc func downloadCount() -> Int {
        return downloadQueue.operationCount
    }
    
    // Read Folder Synchronize
    @objc func readFolderSync(serverUrl: String, selector: String ,account: String) {
        readFolderSyncQueue.addOperation(NCOperationReadFolderSync.init(serverUrl: serverUrl, selector: selector, account: account))
    }
    @objc func readFolderSyncCancelAll() {
        readFolderSyncQueue.cancelAll()
    }
    
    // Download Thumbnail
    @objc func downloadThumbnail(metadata: tableMetadata, activeUrl: String, view: Any, indexPath: IndexPath) {
        if metadata.hasPreview && (!CCUtility.fileProviderStorageIconExists(metadata.ocId, fileNameView: metadata.fileName) || metadata.typeFile == k_metadataTypeFile_document) {
            
            for operation in  downloadThumbnailQueue.operations {
                if (operation as! NCOperationDownloadThumbnail).metadata.ocId == metadata.ocId {
                    return
                }
            }
            downloadThumbnailQueue.addOperation(NCOperationDownloadThumbnail.init(metadata: metadata, activeUrl: activeUrl, view: view, indexPath: indexPath))
        }
    }
    @objc func downloadThumbnailCancelAll() {
        downloadThumbnailQueue.cancelAll()
    }
}

//MARK: -

class NCOperationDownload: ConcurrentOperation {
   
    private var metadata: tableMetadata
    private var selector: String
    private var setFavorite: Bool
    
    init(metadata: tableMetadata, selector: String, setFavorite: Bool) {
        self.metadata = metadata
        self.selector = selector
        self.setFavorite = setFavorite
    }
    
    override func start() {
        if isCancelled {
            self.finish()
        } else {
            NCNetworking.shared.download(metadata: self.metadata, selector: self.selector, setFavorite: self.setFavorite) { (_) in
                self.finish()
            }
        }
    }
}

//MARK: -

class NCOperationReadFolderSync: ConcurrentOperation {
   
    private var serverUrl: String
    private var selector: String
    private var account: String
    
    init(serverUrl: String, selector: String, account: String) {
        self.serverUrl = serverUrl
        self.selector = selector
        self.account = account
    }
    
    override func start() {
        if isCancelled {
            self.finish()
        } else {
            NCCommunication.shared.readFileOrFolder(serverUrlFileName: serverUrl, depth: "1", showHiddenFiles: CCUtility.getShowHiddenFiles()) { (account, files, errorCode, errorDescription) in
                
                if errorCode == 0 && files != nil {
                    NCManageDatabase.sharedInstance.convertNCCommunicationFilesToMetadatas(files!, useMetadataFolder: true, account: account) { (metadataFolder, metadatasFolder, metadatas) in
                        
                        if metadatas.count > 0 {
                            CCSynchronize.shared()?.readFolder(withAccount: account, serverUrl: self.serverUrl, metadataFolder: metadataFolder, metadatas: metadatas, selector: self.selector)
                        }
                    }
                } else if errorCode == 404 {
                    NCManageDatabase.sharedInstance.deleteDirectoryAndSubDirectory(serverUrl: self.serverUrl, account: account)
                }
                self.finish()
            }
        }
    }
}

//MARK: -

class NCOperationDownloadThumbnail: ConcurrentOperation {
   
    var metadata: tableMetadata
    var activeUrl: String
    var view: Any
    var indexPath: IndexPath
    
    init(metadata: tableMetadata, activeUrl: String, view: Any, indexPath: IndexPath) {
        self.metadata = metadata
        self.activeUrl = activeUrl
        self.view = view
        self.indexPath = indexPath
    }
    
    override func start() {

        if isCancelled {
            self.finish()
        } else {
        
            let fileNamePath = CCUtility.returnFileNamePath(fromFileName: metadata.fileName, serverUrl: metadata.serverUrl, activeUrl: activeUrl)!
            let fileNameLocalPath = CCUtility.getDirectoryProviderStorageIconOcId(metadata.ocId, fileNameView: metadata.fileNameView)!

            NCCommunication.shared.downloadPreview(fileNamePathOrFileId: fileNamePath, fileNameLocalPath: fileNameLocalPath, width: Int(k_sizePreview), height: Int(k_sizePreview)) { (account, data, errorCode, errorMessage) in
                
                var cell: NCImageCellProtocol?
                if self.view is UICollectionView && NCMainCommon.sharedInstance.isValidIndexPath(self.indexPath, view: self.view) {
                    cell = (self.view as! UICollectionView).cellForItem(at: self.indexPath) as? NCImageCellProtocol
                } else if self.view is UITableView && NCMainCommon.sharedInstance.isValidIndexPath(self.indexPath, view: self.view) {
                    cell = (self.view as! UITableView).cellForRow(at: self.indexPath) as? NCImageCellProtocol
                }

                if (cell != nil) {
                    var previewImage: UIImage!
                    if errorCode == 0 && data != nil {
                        if let image = UIImage(data: data!) {
                            previewImage = image
                        }
                    } else {
                        if self.metadata.iconName.count > 0 {
                            previewImage = UIImage(named: self.metadata.iconName)
                        } else {
                            previewImage = UIImage(named: "file")
                        }
                    }
                    cell!.filePreviewImageView.backgroundColor = nil
                    UIView.transition(with: cell!.filePreviewImageView,
                        duration: 0.75,
                        options: .transitionCrossDissolve,
                        animations: { cell!.filePreviewImageView.image = previewImage! },
                        completion: nil)
                }
                self.finish()
            }
        }
    }
}