Tusker/Tusker/Screens/Asset Picker/AssetPickerViewController.swift

//
//  AssetPickerViewController.swift
//  Tusker
//
//  Created by Shadowfacts on 1/1/20.
//  Copyright © 2020 Shadowfacts. All rights reserved.
//

import UIKit
import Photos

protocol AssetPickerViewControllerDelegate: AnyObject {
    func assetPicker(_ assetPicker: AssetPickerViewController, shouldAllowAssetOfType type: CompositionAttachmentData.AttachmentType) -> Bool
    func assetPicker(_ assetPicker: AssetPickerViewController, didSelectAttachments attachments: [CompositionAttachmentData])
}

class AssetPickerViewController: UINavigationController {

    weak var assetPickerDelegate: AssetPickerViewControllerDelegate?
    
    var currentCollectionSelectedAssets: [CompositionAttachmentData] {
        if let vc = visibleViewController as? AssetCollectionViewController {
            return vc.selectedAssets.map { .asset($0) }
        } else {
            return []
        }
    }
    
    init() {
        super.init(navigationBarClass: nil, toolbarClass: nil)
    }
    
    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        let assetCollectionsList = AssetCollectionsListViewController()
        assetCollectionsList.assetCollectionDelegate = self
        let assetCollection = AssetCollectionViewController()
        assetCollection.delegate = self
        setViewControllers([assetCollectionsList, assetCollection], animated: false)
    }
    
    func presentImagePicker(animated: Bool) {
        let imagePicker = UIImagePickerController()
        imagePicker.delegate = self
        imagePicker.sourceType = .camera
        imagePicker.mediaTypes = UIImagePickerController.availableMediaTypes(for: .camera)!
        self.present(imagePicker, animated: true)
    }

}

extension AssetPickerViewController: AssetCollectionViewControllerDelegate {
    func shouldSelectAsset(_ asset: PHAsset) -> Bool {
        guard let delegate = assetPickerDelegate else { return true }
        guard let type = asset.attachmentType else { return false }
        return delegate.assetPicker(self, shouldAllowAssetOfType: type)
    }
    func didSelectAssets(_ assets: [PHAsset]) {
        assetPickerDelegate?.assetPicker(self, didSelectAttachments: assets.map { .asset($0) })
    }
    func captureFromCamera() {
        presentImagePicker(animated: true)
    }
}

extension AssetPickerViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate {
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [UIImagePickerController.InfoKey : Any]) {
        let attachment: CompositionAttachmentData
        if let image = info[.originalImage] as? UIImage {
            attachment = .image(image)
        } else if let url = info[.mediaURL] as? URL {
            attachment = .video(url)
        } else {
            return
        }
        
        if assetPickerDelegate?.assetPicker(self, shouldAllowAssetOfType: attachment.type) ?? true {
            assetPickerDelegate?.assetPicker(self, didSelectAttachments: [attachment])
            // dismiss image picker
            dismiss(animated: true) {
                // dismiss asset picker
                self.dismiss(animated: true)
            }
        } else {
            dismiss(animated: false) {
                self.presentImagePicker(animated: false)
            }
        }
    }
}