/*

 Copyright (C) 2016 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 The PhotoDocument subclasses NSDocument and does the basic data abstraction.

*/

import Cocoa

class PhotoDocument: NSDocument {

    /*

        This enumerated type is currently needed due to a Bridging problem that exists between the Swift 3 Error protocol and NSError.

        This will be fixed in a future update.

        For more information see: https://github.com/apple/swift-evolution/blob/master/proposals/0112-nserror-bridging.md

    */

    enum CocoaError : Error {

        case fileReadUnknown

    }

    var photo: Photo?

    override init() {

        super.init()

        hasUndoManager = true

    }

    override class func autosavesInPlace() -> Bool {

        return true

    }

    override func makeWindowControllers() {

        let storyboard = NSStoryboard(name: "Main", bundle: nil)

        let windowController = storyboard.instantiateController(withIdentifier: "Document Window Controller") as! NSWindowController

        addWindowController(windowController)

    }

    override func data(ofType typeName: String) throws -> Data {

        guard let photoToArchive = photo else { throw NSError(domain: NSOSStatusErrorDomain, code: unimpErr, userInfo: nil) }

        return NSKeyedArchiver.archivedData(withRootObject: photoToArchive)

    }

    override func read(from data: Data, ofType typeName: String) throws {

        switch typeName {

            case "JPEG image", "Portable Network Graphics image":

                guard let image = NSImage(data: data) else { throw CocoaError.fileReadUnknown }

                photo = Photo(title: displayName, image: image)

                fileType = "Photo Document"

                fileURL = nil

                // Mark that we did a change so we get a callback to autosave

                updateChangeCount(.changeDone)

            case "Photo Document":

                guard let unarchivedPhoto = NSKeyedUnarchiver.unarchiveObject(with: data) as? Photo else { throw CocoaError.fileReadUnknown }

                photo = unarchivedPhoto

            default:

                throw NSError(domain: NSOSStatusErrorDomain, code: unimpErr, userInfo: nil)

        }

    }

}