//
//  NCFavorite.swift
//  Nextcloud
//
//  Created by Marino Faggiana on 26/08/2020.
//  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

class NCFavorite: UIViewController, UIGestureRecognizerDelegate, NCListCellDelegate, NCGridCellDelegate, NCSectionHeaderMenuDelegate, DZNEmptyDataSetSource, DZNEmptyDataSetDelegate  {
    
    @IBOutlet weak var collectionView: UICollectionView!

    var titleCurrentFolder = NSLocalizedString("_favorites_", comment: "")
    @objc var serverUrl = ""
    
    private let appDelegate = UIApplication.shared.delegate as! AppDelegate
   
    private var metadataPush: tableMetadata?
    private var isEditMode = false
    private var selectocId: [String] = []
    
    private var dataSource: NCDataSource?
    
    private var layout = ""
    private var groupBy = ""
    private var titleButton = ""
    private var itemForLine = 0

    private var autoUploadFileName = ""
    private var autoUploadDirectory = ""
    
    private var listLayout: NCListLayout!
    private var gridLayout: NCGridLayout!
        
    private let headerMenuHeight: CGFloat = 50
    private let sectionHeaderHeight: CGFloat = 20
    private let footerHeight: CGFloat = 50
    
    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        
        appDelegate.activeFavorite = self
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // Cell
        collectionView.register(UINib.init(nibName: "NCListCell", bundle: nil), forCellWithReuseIdentifier: "listCell")
        collectionView.register(UINib.init(nibName: "NCGridCell", bundle: nil), forCellWithReuseIdentifier: "gridCell")
        
        // Header
        collectionView.register(UINib.init(nibName: "NCSectionHeaderMenu", bundle: nil), forSupplementaryViewOfKind: UICollectionView.elementKindSectionHeader, withReuseIdentifier: "sectionHeaderMenu")
        collectionView.register(UINib.init(nibName: "NCSectionHeader", bundle: nil), forSupplementaryViewOfKind: UICollectionView.elementKindSectionHeader, withReuseIdentifier: "sectionHeader")
        
        // Footer
        collectionView.register(UINib.init(nibName: "NCSectionFooter", bundle: nil), forSupplementaryViewOfKind: UICollectionView.elementKindSectionFooter, withReuseIdentifier: "sectionFooter")
        
        collectionView.alwaysBounceVertical = true

        listLayout = NCListLayout()
        gridLayout = NCGridLayout()
        
        // empty Data Source
        self.collectionView.emptyDataSetDelegate = self
        self.collectionView.emptyDataSetSource = self
        
        // 3D Touch peek and pop
        if traitCollection.forceTouchCapability == .available {
            registerForPreviewing(with: self, sourceView: view)
        }
        
        NotificationCenter.default.addObserver(self, selector: #selector(changeTheming), name: NSNotification.Name(rawValue: k_notificationCenter_changeTheming), object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(deleteFile(_:)), name: NSNotification.Name(rawValue: k_notificationCenter_deleteFile), object: nil)
        NotificationCenter.default.addObserver(self, selector: #selector(reloadDataSource), name: NSNotification.Name(rawValue: k_notificationCenter_reloadDataSource), object: nil)

        changeTheming()
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)

        self.navigationItem.title = titleCurrentFolder
                
        // get auto upload folder
        autoUploadFileName = NCManageDatabase.sharedInstance.getAccountAutoUploadFileName()
        autoUploadDirectory = NCManageDatabase.sharedInstance.getAccountAutoUploadDirectory(urlBase: appDelegate.urlBase, account: appDelegate.account)
        
        (layout, _, _, groupBy, _, titleButton, itemForLine) = NCUtility.shared.getLayoutForView(key: k_layout_view_favorite)
        gridLayout.itemForLine = CGFloat(itemForLine)
        
        if layout == k_layout_list {
            collectionView?.collectionViewLayout = listLayout
        } else {
            collectionView?.collectionViewLayout = gridLayout
        }
        
        reloadDataSource()
    }
    
    override func viewDidAppear(_ animated: Bool) {
        super.viewDidAppear(animated)
        
        if serverUrl == "" {
            listingFavorites()
        } else {
            readFolder()
        }
    }
    
    override func viewWillTransition(to size: CGSize, with coordinator: UIViewControllerTransitionCoordinator) {
        super.viewWillTransition(to: size, with: coordinator)
        
        coordinator.animate(alongsideTransition: nil) { _ in
            self.collectionView?.collectionViewLayout.invalidateLayout()
        }
    }
    
    //MARK: - NotificationCenter

    @objc func deleteFile(_ notification: NSNotification) {
        if self.view?.window == nil { return }
        
        if let userInfo = notification.userInfo as NSDictionary? {
            if let metadata = userInfo["metadata"] as? tableMetadata, let errorCode = userInfo["errorCode"] as? Int, let errorDescription = userInfo["errorDescription"] as? String {
                if errorCode == 0 {
                    self.dataSource?.deleteMetadata(ocId: metadata.ocId)
                    collectionView.reloadData()
                } else {
                    NCContentPresenter.shared.messageNotification("_error_", description: errorDescription, delay: TimeInterval(k_dismissAfterSecond), type: NCContentPresenter.messageType.error, errorCode: errorCode)
                }
            }
        }
    }
    
    @objc func changeTheming() {
        appDelegate.changeTheming(self, tableView: nil, collectionView: collectionView, form: false)
    }
    
    // MARK: DZNEmpty
    
    func backgroundColor(forEmptyDataSet scrollView: UIScrollView) -> UIColor? {
        return NCBrandColor.sharedInstance.backgroundView
    }
    
    func image(forEmptyDataSet scrollView: UIScrollView) -> UIImage? {
        return CCGraphics.changeThemingColorImage(UIImage.init(named: "favorite"), width: 300, height: 300, color: NCBrandColor.sharedInstance.yellowFavorite)
    }
    
    func title(forEmptyDataSet scrollView: UIScrollView) -> NSAttributedString? {
        let text = "\n"+NSLocalizedString("_favorite_no_files_", comment: "")
        let attributes = [NSAttributedString.Key.font: UIFont.boldSystemFont(ofSize: 20), NSAttributedString.Key.foregroundColor: UIColor.lightGray]
        return NSAttributedString.init(string: text, attributes: attributes)
    }
    
    func description(forEmptyDataSet scrollView: UIScrollView!) -> NSAttributedString! {
        let text = "\n"+NSLocalizedString("_tutorial_favorite_view_", comment: "")
        let attributes = [NSAttributedString.Key.font: UIFont.systemFont(ofSize: 14), NSAttributedString.Key.foregroundColor: UIColor.lightGray]
        return NSAttributedString.init(string: text, attributes: attributes)
    }
    
    func emptyDataSetShouldAllowScroll(_ scrollView: UIScrollView) -> Bool {
        return true
    }
    
    // MARK: TAP EVENT
    
    func tapSwitchHeader(sender: Any) {
        
        if collectionView.collectionViewLayout == gridLayout {
            // list layout
            UIView.animate(withDuration: 0.0, animations: {
                self.collectionView.collectionViewLayout.invalidateLayout()
                self.collectionView.setCollectionViewLayout(self.listLayout, animated: false, completion: { (_) in
                    self.collectionView.reloadData()
                    self.collectionView.setContentOffset(CGPoint(x:0,y:0), animated: false)
                })
            })
            layout = k_layout_list
            NCUtility.shared.setLayoutForView(key: k_layout_view_favorite, layout: layout)
        } else {
            // grid layout
            UIView.animate(withDuration: 0.0, animations: {
                self.collectionView.collectionViewLayout.invalidateLayout()
                self.collectionView.setCollectionViewLayout(self.gridLayout, animated: false, completion: { (_) in
                    self.collectionView.reloadData()
                    self.collectionView.setContentOffset(CGPoint(x:0,y:0), animated: false)
                })
            })
            layout = k_layout_grid
            NCUtility.shared.setLayoutForView(key: k_layout_view_favorite, layout: layout)
        }
    }
    
    func tapOrderHeader(sender: Any) {
        
        let sortMenu = NCSortMenu()
        sortMenu.toggleMenu(viewController: self, key: k_layout_view_favorite, sortButton: sender as? UIButton, serverUrl: serverUrl)
    }
    
    func tapMoreHeader(sender: Any) {
        
    }
    
    func tapMoreListItem(with objectId: String, sender: Any) {
        tapMoreGridItem(with: objectId, sender: sender)
    }
    
    func tapShareListItem(with objectId: String, sender: Any) {
        
        guard let metadata = NCManageDatabase.sharedInstance.getMetadata(predicate: NSPredicate(format: "ocId == %@", objectId)) else {
            return
        }
        
        NCMainCommon.sharedInstance.openShare(ViewController: self, metadata: metadata, indexPage: 2)
    }
    
    func tapMoreGridItem(with objectId: String, sender: Any) {
        
        guard let metadata = NCManageDatabase.sharedInstance.getMetadata(predicate: NSPredicate(format: "ocId == %@", objectId)) else { return }
        guard let tabBarController = self.tabBarController else { return }
        
        toggleMoreMenu(viewController: tabBarController, metadata: metadata)
    }
    
    // MARK: SEGUE
    
    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        
        let photoDataSource: NSMutableArray = []
        
        for metadata in (dataSource?.metadatas ?? [tableMetadata]()) {
            if metadata.typeFile == k_metadataTypeFile_image || metadata.typeFile == k_metadataTypeFile_video {
                photoDataSource.add(metadata)
            }
        }
        
        if let segueNavigationController = segue.destination as? UINavigationController {
            if let segueViewController = segueNavigationController.topViewController as? NCDetailViewController {
            
                segueViewController.metadata = metadataPush
            }
        }
    }
}

// MARK: - 3D Touch peek and pop

extension NCFavorite: UIViewControllerPreviewingDelegate {
    
    func previewingContext(_ previewingContext: UIViewControllerPreviewing, viewControllerForLocation location: CGPoint) -> UIViewController? {
        
        guard let point = collectionView?.convert(location, from: collectionView?.superview) else { return nil }
        guard let indexPath = collectionView?.indexPathForItem(at: point) else { return nil }
        guard let metadata = dataSource?.cellForItemAt(indexPath: indexPath) else { return nil }
        guard let viewController = UIStoryboard(name: "CCPeekPop", bundle: nil).instantiateViewController(withIdentifier: "PeekPopImagePreview") as? CCPeekPop else { return nil }

        viewController.metadata = metadata

        if layout == k_layout_grid {
            guard let cell = collectionView?.cellForItem(at: indexPath) as? NCGridCell else { return nil }
            previewingContext.sourceRect = cell.frame
            viewController.imageFile = cell.imageItem.image
        } else {
            guard let cell = collectionView?.cellForItem(at: indexPath) as? NCListCell else { return nil }
            previewingContext.sourceRect = cell.frame
            viewController.imageFile = cell.imageItem.image
        }
        
        viewController.showOpenIn = true
        viewController.showOpenQuickLook = NCUtility.shared.isQuickLookDisplayable(metadata: metadata)
        viewController.showShare = false
        
        return viewController
    }
    
    func previewingContext(_ previewingContext: UIViewControllerPreviewing, commit viewControllerToCommit: UIViewController) {
        
        guard let indexPath = collectionView?.indexPathForItem(at: previewingContext.sourceRect.origin) else { return }
        
        collectionView(collectionView, didSelectItemAt: indexPath)
    }
}

// MARK: - Collection View

extension NCFavorite: UICollectionViewDelegate {

    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        
        guard let metadata = dataSource?.cellForItemAt(indexPath: indexPath) else { return }
        metadataPush = metadata
        
        if isEditMode {
            if let index = selectocId.firstIndex(of: metadata.ocId) {
                selectocId.remove(at: index)
            } else {
                selectocId.append(metadata.ocId)
            }
            collectionView.reloadItems(at: [indexPath])
            return
        }
        
        if metadata.directory {
            
            guard let serverUrlPush = CCUtility.stringAppendServerUrl(metadataPush!.serverUrl, addFileName: metadataPush!.fileName) else { return }
            let ncFavorite:NCFavorite = UIStoryboard(name: "NCFavorite", bundle: nil).instantiateInitialViewController() as! NCFavorite
            
            ncFavorite.serverUrl = serverUrlPush
            ncFavorite.titleCurrentFolder = metadataPush!.fileNameView
            
            self.navigationController?.pushViewController(ncFavorite, animated: true)
            
        } else {
            
            performSegue(withIdentifier: "segueDetail", sender: self)
        }
    }
}

extension NCFavorite: UICollectionViewDataSource {

    func collectionView(_ collectionView: UICollectionView, viewForSupplementaryElementOfKind kind: String, at indexPath: IndexPath) -> UICollectionReusableView {
        
        if (indexPath.section == 0) {
            
            if kind == UICollectionView.elementKindSectionHeader {
                
                let header = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: "sectionHeaderMenu", for: indexPath) as! NCSectionHeaderMenu
                
                if collectionView.collectionViewLayout == gridLayout {
                    header.buttonSwitch.setImage(CCGraphics.changeThemingColorImage(UIImage.init(named: "switchList"), multiplier: 2, color: NCBrandColor.sharedInstance.icon), for: .normal)
                } else {
                    header.buttonSwitch.setImage(CCGraphics.changeThemingColorImage(UIImage.init(named: "switchGrid"), multiplier: 2, color: NCBrandColor.sharedInstance.icon), for: .normal)
                }
                
                header.delegate = self
                header.backgroundColor = NCBrandColor.sharedInstance.backgroundView
                header.separator.backgroundColor = NCBrandColor.sharedInstance.separator
                header.setStatusButton(count: dataSource?.metadatas.count ?? 0)
                header.setTitleSorted(datasourceTitleButton: titleButton)
                
                if groupBy == "none" {
                    header.labelSection.isHidden = true
                    header.labelSectionHeightConstraint.constant = 0
                } else {
                    header.labelSection.isHidden = false
                    header.setTitleLabel(title: "")
                    header.labelSectionHeightConstraint.constant = sectionHeaderHeight
                }
                
                return header
                
            } else {
                
                let footer = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: "sectionFooter", for: indexPath) as! NCSectionFooter
                
                let info = dataSource?.getFilesInformation()
                footer.setTitleLabel(directories: info?.directories ?? 0, files: info?.files ?? 0, size: info?.size ?? 0)
                
                return footer
            }
            
        } else {
            
            if kind == UICollectionView.elementKindSectionHeader {
                
                let header = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: "sectionHeader", for: indexPath) as! NCSectionHeader
                
                header.setTitleLabel(title: "")
                
                return header
                
            } else {
                
                let footer = collectionView.dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: "sectionFooter", for: indexPath) as! NCSectionFooter
                
                let info = dataSource?.getFilesInformation()
                footer.setTitleLabel(directories: info?.directories ?? 0, files: info?.files ?? 0, size: info?.size ?? 0)
                
                return footer
            }
        }
    }
    
    func numberOfSections(in collectionView: UICollectionView) -> Int {
        return dataSource?.sections ?? 1
    }
    
    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return dataSource?.numberOfItemsInSection(section: section) ?? 1
    }
    
    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        
        let cell: UICollectionViewCell
        
        guard let metadata = dataSource?.cellForItemAt(indexPath: indexPath) else {
            return collectionView.dequeueReusableCell(withReuseIdentifier: "listCell", for: indexPath) as! NCListCell
        }
        
        if layout == k_layout_grid {
            cell = collectionView.dequeueReusableCell(withReuseIdentifier: "gridCell", for: indexPath) as! NCGridCell
        } else {
            cell = collectionView.dequeueReusableCell(withReuseIdentifier: "listCell", for: indexPath) as! NCListCell
            (cell as! NCListCell).separator.backgroundColor = NCBrandColor.sharedInstance.separator
        }
        
        let shares = NCManageDatabase.sharedInstance.getTableShares(account: metadata.account, serverUrl: metadata.serverUrl, fileName: metadata.fileName)
        
        NCMainCommon.sharedInstance.collectionViewCellForItemAt(indexPath, collectionView: collectionView, cell: cell, metadata: metadata, metadataFolder: nil, serverUrl: metadata.serverUrl, isEditMode: isEditMode, selectocId: selectocId, autoUploadFileName: autoUploadFileName, autoUploadDirectory: autoUploadDirectory, hideButtonMore: false, downloadThumbnail: true, shares: shares, source: self)
        
        return cell
    }
}

extension NCFavorite: UICollectionViewDelegateFlowLayout {

    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForHeaderInSection section: Int) -> CGSize {
        if section == 0 {
            if groupBy == "none" {
                return CGSize(width: collectionView.frame.width, height: headerMenuHeight)
            } else {
                return CGSize(width: collectionView.frame.width, height: headerMenuHeight + sectionHeaderHeight)
            }
        } else {
            return CGSize(width: collectionView.frame.width, height: sectionHeaderHeight)
        }
    }
    
    func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, referenceSizeForFooterInSection section: Int) -> CGSize {
        let sections = dataSource?.sections ?? 1
        if (section == sections - 1) {
            return CGSize(width: collectionView.frame.width, height: footerHeight)
        } else {
            return CGSize(width: collectionView.frame.width, height: 0)
        }
    }
}

// MARK: - NC API & Algorithm

extension NCFavorite {

    @objc func reloadDataSource() {
        
        var sort: String
        var ascending: Bool
        var directoryOnTop: Bool
        
        (layout, sort, ascending, groupBy, directoryOnTop, titleButton, itemForLine) = NCUtility.shared.getLayoutForView(key: k_layout_view_favorite)
        
        if serverUrl == "" {
            
            let metadatasSource = NCManageDatabase.sharedInstance.getMetadatas(predicate: NSPredicate(format: "account == %@ AND favorite == true", appDelegate.account))
            
            self.dataSource = NCDataSource.init(metadatasSource: metadatasSource, sort: sort, ascending: ascending, directoryOnTop: directoryOnTop, filterLivePhoto: true)
            
        } else {
            
            let metadatasSource = NCManageDatabase.sharedInstance.getMetadatas(predicate: NSPredicate(format: "account == %@ AND serverUrl == %@", appDelegate.account, serverUrl))
            
            self.dataSource = NCDataSource.init(metadatasSource: metadatasSource, sort: sort, ascending: ascending, directoryOnTop: directoryOnTop, filterLivePhoto: true)
        }
        
        collectionView.reloadData()
    }
    
    private func readFolder() {
        NCNetworking.shared.readFolder(serverUrl: serverUrl, account: appDelegate.account) { (account, metadataFolder, metadatas, metadatasUpdate, metadatasLocalUpdate, errorCode, errorDescription) in
            if errorCode == 0 {
                for metadata in metadatas ?? [] {
                    if !metadata.directory {
                        let localFile = NCManageDatabase.sharedInstance.getTableLocalFile(predicate: NSPredicate(format: "ocId == %@", metadata.ocId))
                        if localFile == nil || localFile?.etag != metadata.etag {
                            NCOperationQueue.shared.download(metadata: metadata, selector: selectorDownloadFile, setFavorite: false)
                        }
                    }
                }
                self.reloadDataSource()
            }
        }
    }
    
    private func listingFavorites() {
        NCNetworking.shared.listingFavoritescompletion(selector: selectorListingFavorite) { (account, metadatas, errorCode, errorDescription) in
            if errorCode == 0 {
                for metadata in metadatas ?? [] {
                    if !metadata.directory && CCUtility.getFavoriteOffline() {
                        let localFile = NCManageDatabase.sharedInstance.getTableLocalFile(predicate: NSPredicate(format: "ocId == %@", metadata.ocId))
                        if localFile == nil || localFile?.etag != metadata.etag {
                            NCOperationQueue.shared.download(metadata: metadata, selector: selectorDownloadFile, setFavorite: false)
                        }
                    }
                }
                self.reloadDataSource()
            }
        }
    }
}