//
//  BookmarkListViewController.swift
//  KCD
//
//  Created by Hori,Masaki on 2016/12/23.
//  Copyright © 2016年 Hori,Masaki. All rights reserved.
//

import Cocoa

protocol BookmarkListViewControllerDelegate: class {
    
    func didSelectBookmark(_ bookmark: Bookmark)
}

extension NSPasteboard.PasteboardType {
    
    static let bookmarkItem = NSPasteboard.PasteboardType("com.masakih.KCD.BookmarkItem")
}

final class BookmarkListViewController: NSViewController {
    
    @objc let managedObjectContext = BookmarkManager.shared.manageObjectContext
    
    @IBOutlet private var tableView: NSTableView!
    @IBOutlet private var bookmarkController: NSArrayController!
    @IBOutlet private var contextMenu: NSMenu!
    @IBOutlet private var popover: NSPopover!
    
    weak var delegate: BookmarkListViewControllerDelegate?
    var editorController: BookmarkEditorViewController?
    
    // tableView support
    var draggingRange: CountableClosedRange = 0...0
    
    override var nibName: NSNib.Name {
        
        return .nibName(instanceOf: self)
    }
    
    override func viewDidLoad() {
        
        super.viewDidLoad()
        
        editorController = BookmarkEditorViewController()
        popover.contentViewController = editorController
        
        tableView.registerForDraggedTypes([.bookmarkItem])
        tableView.setDraggingSourceOperationMask(.move, forLocal: true)
    }
    
    @IBAction func editBookmark(_ sender: AnyObject?) {
        
        let clickedRow = tableView.clickedRow
        
        guard let bookmarks = bookmarkController.arrangedObjects as? [Any] else {
            
            return
        }
        guard case 0..<bookmarks.count = clickedRow else {
            
            return
        }
        
        editorController?.representedObject = bookmarks[clickedRow]
        popover.show(relativeTo: tableView.rect(ofRow: clickedRow), of: tableView, preferredEdge: .minY)
    }
    
    @IBAction func deleteBookmark(_ sender: AnyObject?) {
        
        let clickedRow = tableView.clickedRow
        
        guard let bookmarks = bookmarkController.arrangedObjects as? [Any] else {
            
            return
        }
        guard case 0..<bookmarks.count = clickedRow else {
            
            return
        }
        
        bookmarkController.remove(atArrangedObjectIndex: clickedRow)
    }
}

extension BookmarkListViewController: NSTableViewDelegate, NSTableViewDataSource {
    
    func reorderingBoolmarks() {
        
        guard let objects = bookmarkController.arrangedObjects as? [Bookmark] else {
            
            return
        }
        
        var order = 100
        objects.forEach {
            
            $0.order = order
            order += 100
        }
    }
    
    func tableViewSelectionDidChange(_ notification: Notification) {
        
        guard let tableView = notification.object as? NSTableView else {
            
            return
        }
        guard let bookmarks = bookmarkController.arrangedObjects as? [Bookmark] else {
            
            return
        }
        
        let selection = tableView.selectedRow
        tableView.deselectAll(nil)
        
        guard case 0..<bookmarks.count = selection else {
            
            return
        }
        
        delegate?.didSelectBookmark(bookmarks[selection])
    }
    
    func tableView(_ tableView: NSTableView, pasteboardWriterForRow row: Int) -> NSPasteboardWriting? {
        
        guard let objects = bookmarkController.arrangedObjects as? [NSPasteboardWriting] else {
            
            return nil
        }
        
        return objects[row]
    }
    
    func tableView(_ tableView: NSTableView, draggingSession session: NSDraggingSession, willBeginAt screenPoint: NSPoint, forRowIndexes rowIndexes: IndexSet) {
        
        guard let first = rowIndexes.first else {
            
            return
        }
        guard let last = rowIndexes.last else {
            
            return
        }
        
        draggingRange = first...last
    }
    
    func tableView(_ tableView: NSTableView, draggingSession session: NSDraggingSession, endedAt screenPoint: NSPoint, operation: NSDragOperation) {
        
        draggingRange = 0...0
    }
    
    func tableView(_ tableView: NSTableView,
                   validateDrop info: NSDraggingInfo,
                   proposedRow row: Int,
                   proposedDropOperation dropOperation: NSTableView.DropOperation) -> NSDragOperation {
        
        guard dropOperation == .above else {
            
            return []
        }
        guard !(draggingRange ~= row) else {
            
            return []
        }
        guard let tableView = info.draggingSource() as? NSTableView, tableView == self.tableView else {
            
            return []
        }
        
        return .move
    }
    
    func tableView(_ tableView: NSTableView, acceptDrop info: NSDraggingInfo, row: Int, dropOperation: NSTableView.DropOperation) -> Bool {
        
        tableView.beginUpdates()
        defer { tableView.endUpdates() }
        
        let targetOrder: Int = {
            
            guard let objects = bookmarkController.arrangedObjects as? [Any],
                case 1...objects.count = row,
                let target = objects[row - 1] as? Bookmark else {
                    
                    return 0
            }
            
            return target.order
        }()
        
        guard let items = info.draggingPasteboard().pasteboardItems else {
            
            return false
        }
        
        let store = BookmarkManager.shared.editorStore
        store.sync {
            
            items.enumerated().forEach {
                
                guard let data = $0.element.data(forType: .bookmarkItem) else {
                    
                    return
                }
                guard let uri = NSKeyedUnarchiver.unarchiveObject(with: data) as? URL else {
                    
                    return
                }
                guard let bookmark = store.object(of: Bookmark.self, forURIRepresentation: uri) else {
                    
                    return
                }
                
                bookmark.order = targetOrder + $0.offset + 1
            }
            
            store.save()
            
            self.bookmarkController.rearrangeObjects()
            self.reorderingBoolmarks()
            self.bookmarkController.rearrangeObjects()
        }
        
        tableView.reloadData()
        
        return true
    }
}