gistfile1.txt

final class FeedViewController: UIViewController {
    private let viewModel: FeedViewModel
    private let assetStore: AssetStore
    private let collectionView: UICollectionView
    private let statsToolbarView = StatsToolbarView()
    private let navBarGradientView = GradientView(
        colors: [FeedSpec.NavigationBar.gradientTop, FeedSpec.NavigationBar.gradientBottom],
        startPoint: CGPoint(x: 0.5, y: 0.0),
        endPoint: CGPoint(x: 0.5, y: 1.0)
    )
    private var currentStatsItemID: Int?
    private var navBarGradientHeightConstraint: NSLayoutConstraint?
    // ...
}

extension FeedViewController: UICollectionViewDataSource {
    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        guard let cell = collectionView.dequeueReusableCell(
            withReuseIdentifier: FeedCell.reuseIdentifier,
            for: indexPath
        ) as? FeedCell else {
            return UICollectionViewCell()
        }
        let item = viewModel.visibleItems[indexPath.item]
        cell.configure(with: item, assetStore: assetStore)
        cell.onStickerUpdated = { [weak self] itemID, stickerID, centerUnit, scale, rotation in
            self?.viewModel.updateSticker(
                itemID: itemID,
                stickerID: stickerID,
                centerUnit: centerUnit,
                scale: scale,
                rotation: rotation
            )
        }
        cell.onStickerDeleted = { [weak self] itemID, stickerID in
            self?.viewModel.deleteSticker(itemID: itemID, stickerID: stickerID)
        }
        return cell
    }
}