//
//  DetailViewController.swift
//  kplayer
//
//  Created by Marco Schmickler on 24.05.15.
//  Copyright (c) 2015 Marco Schmickler. All rights reserved.
//

import UIKit
import Alamofire
import FileBrowser
import AVFoundation
import ZIPFoundation
import SwiftUI

protocol DetailDelegate {
    func loadDetails(selectedItem: MediaItem, completionHandler: @escaping () -> Void)
    func deleteThumb(selectedItem: MediaItem)
    func deleteLocal(selectedItem: MediaItem)
    func saveItem(selectedItem: MediaItem)
    func favItem(_ item: MediaItem)
    func settings() -> KSettings
    func offline() -> Bool
}

class DetailViewController: UIViewController, UICollectionViewDelegateFlowLayout, UICollectionViewDataSource, UICollectionViewDragDelegate {

    var delegate : DetailDelegate?
    @IBOutlet weak var detailDescriptionLabel: UILabel!

    var showFavoritesOnly = false
    var collectionView: UICollectionView!

    var currentItem: MediaItem?

    var defaultItemSize = CGSize(width: (15 * 16) - 6, height: 15 * 9)

    var modeButton: UIBarButtonItem?
    var mode = false

    var detailItem: MediaItem? {
        didSet {
      //      print(detailItem!.children)
            if collectionView != nil {
                collectionView.reloadData()
            }
        }
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        NotificationCenter.default.addObserver(self, selector: #selector(refreshItems(_:)), name: NSNotification.Name(rawValue: "loadedItems"), object: nil)
    }

    deinit {
        NotificationCenter.default.removeObserver(self, name: NSNotification.Name(rawValue: "loadedItems"), object: nil)
    }

    override func viewDidLoad() {
        super.viewDidLoad()

        let layout: UICollectionViewFlowLayout = UICollectionViewFlowLayout()

        layout.sectionInset = UIEdgeInsets(top: 1, left: 0, bottom: 1, right: 0)
        layout.minimumInteritemSpacing = 0.0;

        layout.itemSize = defaultItemSize
        layout.headerReferenceSize = CGSize(width: 50, height: 50)
        collectionView = UICollectionView(frame: view.frame, collectionViewLayout: layout)

        collectionView.dataSource = self
        collectionView.delegate = self
        collectionView.register(ItemCell.self, forCellWithReuseIdentifier: "Cell")
        collectionView.backgroundColor = UIColor.lightGray
        collectionView.register(HeaderCell.self, forSupplementaryViewOfKind: UICollectionView.elementKindSectionHeader, withReuseIdentifier: "HeaderView");
        collectionView.dragInteractionEnabled = true
        collectionView.dragDelegate = self

        view.addSubview(collectionView)
        view.autoresizesSubviews = true
        collectionView.autoresizingMask = [UIView.AutoresizingMask.flexibleWidth, UIView.AutoresizingMask.flexibleHeight]
        // Do any additional setup after loading the view, typically from a nib.

        collectionView.reloadData()

        // attach long press gesture to collectionView
        let lpgr = UILongPressGestureRecognizer(target: self, action: #selector(handleLongPress(_:)))
        lpgr.minimumPressDuration = 1;
        //seconds
        lpgr.delaysTouchesBegan = true
        self.collectionView.addGestureRecognizer(lpgr);

        modeButton = UIBarButtonItem(barButtonSystemItem: .search , target: self, action: #selector(switchMode));
        let settingsButton = UIBarButtonItem(barButtonSystemItem: .edit, target: self, action: #selector(settings));
        let overviewButton = UIBarButtonItem(barButtonSystemItem: .action, target: self, action: #selector(overview));
        let favButton = UIBarButtonItem(barButtonSystemItem: .bookmarks, target: self, action: #selector(favorites));
        let browserButton = UIBarButtonItem(barButtonSystemItem: .organize, target: self, action: #selector(fileBrowser));
        navigationItem.rightBarButtonItems = [settingsButton, favButton, overviewButton,browserButton,modeButton!]
        if detailItem != nil {
            if detailItem!.children != nil {
                var d = detailItem!.children
        //        print("Details \(d)")
            }
        }
    }

    @objc func switchMode() {
        mode = !mode
        if let b = modeButton {
            b.isSelected = mode
        }
    }

    // https://github.com/marmelroy/FileBrowser
    @objc func fileBrowser() {
        let d = FileHelper.getDocumentsDirectory()

        LocalManager.sharedInstance.prepareLocalFolder()

        let fileBrowser = FileBrowser(initialPath: d, allowEditing: true)
        fileBrowser.modalPresentationStyle = .fullScreen

        present(fileBrowser, animated: true, completion: nil)
    }

    // Favorites Button
    @objc func favorites() {
        showFavoritesOnly = !showFavoritesOnly
        collectionView.reloadData()
    }

    // Edit Settings Button
    @objc func settings() {
        let kv = KSettingsView(kSettings: LocalManager.sharedInstance.settings, completionHandler: {
            self.dismiss(animated: true, completion: nil);
        } )
        let pc = UIHostingController(rootView: kv)
        let navController = UINavigationController(rootViewController: pc) // Creating a navigation controller with pc at the root of the navigation stack.
        navController.modalPresentationStyle = .fullScreen

        present(navController, animated: false, completion: nil)
    }

    // Overview Button
    @objc func overview() {
        var i = [MediaItem]()

        if let d = detailItem {
            showAllVideos(d)
            return

            let pc = MediaPhotoController()

            for it in d.children {
                if it.children.count > 1 || !showFavoritesOnly {
                    for c in it.children {
                        i.append(c)
                    }
                }
            }

            pc.items = i
            pc.completionHandler = {
                self.dismiss(animated: true, completion: nil);
            }
            let navController = UINavigationController(rootViewController: pc) // Creating a navigation controller with pc at the root of the navigation stack.
            navController.modalPresentationStyle = .fullScreen

            present(navController, animated: false, completion: nil)
        }
    }


    @objc func refreshItems(_ notification: Notification) {
        if notification.object == nil {
            if self.collectionView != nil {
                self.collectionView.reloadData()
            }
            return
        }

        let i = notification.object as! MediaItem
        let index = i.index

        let oid = ObjectIdentifier(self)

        if let detail: MediaItem = self.detailItem {
            if i.type == ItemType.VIDEO {
                let set = IndexSet(integer: index)
                if index < detail.children.count {
                    if (collectionView != nil) {
                        collectionView.reloadSections(set)
                    }
                }
            } else {
                if i.parent! !== detail {
                    return
                }

                print("Object: \(oid.hashValue) Index \(index) Item: \(i) Parent: \(i.parent) Detail: \(detailItem)")

                collectionView.performBatchUpdates({
                    var newItems = [IndexPath]()
                    var j = 0

                    if detail.children.count > index {
                        let path = IndexPath(item: 0, section: index)
                        self.collectionView.reloadItems(at: [path])

                        for _ in detail.children[index].children {
                            if j >= 1 {
                                newItems.append(IndexPath(item: j, section: index))
                            }
                            j += 1
                        }
                        self.collectionView.insertItems(at: newItems)
                    }
                    return
                }, completion: nil)
            }
        }
    }

    // delete item
    @objc func handleLongPress(_ gestureRecognizer: UILongPressGestureRecognizer) {
        if (gestureRecognizer.state != UIGestureRecognizer.State.ended) {
            return;
        }
        let p = gestureRecognizer.location(in: self.collectionView);

        let indexPath = self.collectionView.indexPathForItem(at: p);
        if (indexPath == nil) {
            print("couldn't find index path");
        } else {
            if let detail: MediaItem = self.detailItem {
                let refreshAlert = UIAlertController(title: "Delete", message: "All data will be lost.", preferredStyle: UIAlertController.Style.alert)

                refreshAlert.addAction(UIAlertAction(title: "Ok", style: .default, handler: { (action: UIAlertAction!) in

                    let items = detail.children[indexPath!.section]
                    if (items.loaded) {
                        if (items.root == "/tags") {
                            //
                        }
                        else {
                            if items.children.count == 0 {
                            } else {
                                if indexPath!.item >= items.children.count {
                                } else {
                                    let c = items.children.remove(at: indexPath!.item)

                                    self.delegate!.deleteThumb(selectedItem: c)
                                    self.collectionView.reloadData()
                                }
                            }
                        }
                    }
                    else if items.local {
                      //  self.delegate!.deleteLocal(selectedItem: items)
                    }
                }))

                refreshAlert.addAction(UIAlertAction(title: "Cancel", style: .cancel, handler: { (action: UIAlertAction!) in
                    print("Handle Cancel Logic here")
                }))

                present(refreshAlert, animated: true, completion: nil)

            }
        }
    }

    func numberOfSections(in collectionView: UICollectionView) -> Int {
        if let detail: MediaItem = self.detailItem {
            let cnt = detail.children.count
            return cnt
        }
        return 0
    }

    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        if let detail: MediaItem = self.detailItem {
            let n = detail.children[section].children.count

            if n < 2 && showFavoritesOnly {
                return 0
            }

            if n == 0 && !showFavoritesOnly {
                return 1
            }
            return n
        }
        return 0
    }

    // show cell
    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "Cell", for: indexPath) as! ItemCell

        if let detail: MediaItem = self.detailItem {
            let items = detail.children[indexPath.section]
            if items.children.count == 0 {
                cell.setItem(items)
            } else {
                if indexPath.item >= items.children.count {
                    cell.setItem(items)
                } else {
                    let item = items.children[indexPath.item]
                    cell.setItem(item)
                }
            }
        }
        return cell
    }

    // show Section header
    func collectionView(_ collectionView: UICollectionView,
                        viewForSupplementaryElementOfKind kind: String,
                        at indexPath: IndexPath) -> UICollectionReusableView {
        switch kind {
        case UICollectionView.elementKindSectionHeader:
            let headerView =
                    collectionView.dequeueReusableSupplementaryView(ofKind: kind,
                            withReuseIdentifier: "HeaderView",
                            for: indexPath)
                            as! HeaderCell
            let items = detailItem!.children[indexPath.section]

            headerView.setItem(items)
            return headerView
        default:
            fatalError("Unexpected element kind")
        }
    }

    // select item

    func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        if let detail: MediaItem = self.detailItem {
            print(detail.toJSON())

            let sectionItem = detail.children[indexPath.section]
            currentItem = sectionItem

            if currentItem!.type == .PICS {
                currentItem = sectionItem.clone()
            }
            if currentItem!.type == .FOLDER {
                currentItem = sectionItem.children[indexPath.item]
            }

            var selectedItem = sectionItem

            let weiter: () -> Void = {
              //  if (sectionItem.type == ItemType.VIDEO || sectionItem.loaded) {
                    if indexPath.item >= sectionItem.children.count {
                        selectedItem = sectionItem
                        print(sectionItem.name)
                    } else {
                        selectedItem = sectionItem.children[indexPath.item]
                        print(selectedItem.name)
                    }
              //  }
                self.showDetails(sectionItem: self.currentItem!, selectedItem: selectedItem)
            }

            delegate!.loadDetails(selectedItem: currentItem!, completionHandler: weiter)
        }
    }

    // Drag and drop

    func collectionView(_ collectionView: UICollectionView, itemsForBeginning session: UIDragSession, at indexPath: IndexPath) -> [UIDragItem] {
        if let detail: MediaItem = self.detailItem {
            var selectedItem = detail.children[indexPath.section]

            if selectedItem.children.count > indexPath.item {
                selectedItem = selectedItem.children[indexPath.item]
            }

            if !selectedItem.local {
            //    return []
            }

            let itemProvider = NSItemProvider(object: selectedItem.toJSON() as NSString)
            return [UIDragItem(itemProvider: itemProvider)]
        }
        return []
    }

    func collectionView(_ collectionView: UICollectionView, dragSessionDidEnd session: UIDragSession) {
        collectionView.reloadData()
    }
}