| 1 | import QuickLook |
| 2 | import SwiftUI |
| 3 | import UIKit |
| 4 | |
| 5 | // 🤖 A photo opened from a chat bubble: the full-res bytes staged to a temp file |
| 6 | // for Quick Look, plus the thumbnail + its on-screen frame so the preview can |
| 7 | // ZOOM out of the bubble it came from. |
| 8 | struct QuickLookItem: Identifiable { |
| 9 | let id: String |
| 10 | let url: URL // staged temp file (full-res decrypted bytes) |
| 11 | let thumbnail: UIImage // zoom-transition anchor image |
| 12 | let sourceFrame: CGRect // the tapped thumbnail's window frame |
| 13 | } |
| 14 | |
| 15 | // 🤖 Presents QLPreviewController IMPERATIVELY (not via .sheet) so Quick Look |
| 16 | // owns the transition: given a transition view, it zooms the photo out of its |
| 17 | // bubble on open and back into it on dismiss — the Photos/Files feel — and |
| 18 | // carries Apple's own chrome plus the system Share/Save action button, so there |
| 19 | // are no hand-rolled controls to style. The representable itself is an invisible |
| 20 | // host; the preview is presented from the window's top-most controller and torn |
| 21 | // down (with the caller's onClose) when Quick Look dismisses. |
| 22 | struct ImageQuickLookPresenter: UIViewControllerRepresentable { |
| 23 | @Binding var item: QuickLookItem? |
| 24 | let onClose: () -> Void |
| 25 | |
| 26 | func makeCoordinator() -> Coordinator { Coordinator(onClose: onClose) } |
| 27 | func makeUIViewController(context: Context) -> UIViewController { UIViewController() } |
| 28 | |
| 29 | func updateUIViewController(_ host: UIViewController, context: Context) { |
| 30 | context.coordinator.sync(item: item, host: host) |
| 31 | } |
| 32 | |
| 33 | final class Coordinator: NSObject, QLPreviewControllerDataSource, QLPreviewControllerDelegate { |
| 34 | private let onClose: () -> Void |
| 35 | private var current: QuickLookItem? |
| 36 | private weak var preview: QLPreviewController? |
| 37 | private var transitionView: UIImageView? |
| 38 | private var presenting = false |
| 39 | |
| 40 | init(onClose: @escaping () -> Void) { self.onClose = onClose } |
| 41 | |
| 42 | // Present when an item arrives; dismiss if it's cleared while still up. |
| 43 | // Presentation is deferred a runloop turn so it never runs mid-update. |
| 44 | func sync(item: QuickLookItem?, host: UIViewController) { |
| 45 | // Boot Quick Look's out-of-process renderer once, invisibly, so the |
| 46 | // first real tap doesn't flash its cold-start chrome. |
| 47 | QuickLookWarmup.warmIfNeeded(scene: host.view.window?.windowScene) |
| 48 | if let item, !presenting { |
| 49 | current = item |
| 50 | presenting = true |
| 51 | DispatchQueue.main.async { [weak self, weak host] in |
| 52 | guard let self, let host else { return } |
| 53 | self.present(from: host) |
| 54 | } |
| 55 | } else if item == nil, presenting { |
| 56 | preview?.dismiss(animated: true) |
| 57 | } |
| 58 | } |
| 59 | |
| 60 | private func present(from host: UIViewController) { |
| 61 | guard let window = host.view.window else { presenting = false; return } |
| 62 | var top = window.rootViewController |
| 63 | while let next = top?.presentedViewController { top = next } |
| 64 | guard let top else { presenting = false; return } |
| 65 | let ql = QLPreviewController() |
| 66 | ql.dataSource = self |
| 67 | ql.delegate = self |
| 68 | preview = ql |
| 69 | top.present(ql, animated: true) |
| 70 | } |
| 71 | |
| 72 | // MARK: - Data source |
| 73 | func numberOfPreviewItems(in controller: QLPreviewController) -> Int { |
| 74 | current == nil ? 0 : 1 |
| 75 | } |
| 76 | |
| 77 | func previewController(_ controller: QLPreviewController, |
| 78 | previewItemAt index: Int) -> QLPreviewItem { |
| 79 | PreviewFile(url: current?.url) |
| 80 | } |
| 81 | |
| 82 | // MARK: - Delegate (the zoom anchor) |
| 83 | // A one-off UIImageView pinned at the thumbnail's window frame, showing |
| 84 | // the same downsampled image. Quick Look zooms its preview out of this |
| 85 | // view on open and back into it on dismiss. Reused across the open/close |
| 86 | // calls and removed once the preview is gone. |
| 87 | func previewController(_ controller: QLPreviewController, |
| 88 | transitionViewFor item: QLPreviewItem) -> UIView? { |
| 89 | if let transitionView { return transitionView } |
| 90 | guard let current, |
| 91 | let window = controller.view.window |
| 92 | ?? preview?.presentingViewController?.view.window else { return nil } |
| 93 | let iv = UIImageView(image: current.thumbnail) |
| 94 | iv.frame = current.sourceFrame |
| 95 | iv.contentMode = .scaleAspectFill |
| 96 | iv.clipsToBounds = true |
| 97 | iv.layer.cornerRadius = 18 |
| 98 | iv.layer.cornerCurve = .continuous |
| 99 | window.addSubview(iv) |
| 100 | transitionView = iv |
| 101 | return iv |
| 102 | } |
| 103 | |
| 104 | // The anchor lives on the window, ABOVE the chat header — so when Quick |
| 105 | // Look reveals it at the tail of the zoom-back it would briefly draw |
| 106 | // over the header/avatar (the flash). Fade it out across the dismiss so |
| 107 | // there's nothing to flash: the real, header-clipped thumbnail is |
| 108 | // already underneath. Quick Look cross-fades its shrinking snapshot into |
| 109 | // this view too, so a fading target also fades the zoom itself. |
| 110 | func previewControllerWillDismiss(_ controller: QLPreviewController) { |
| 111 | guard let transitionView else { return } |
| 112 | UIView.animate(withDuration: 0.3) { transitionView.alpha = 0 } |
| 113 | } |
| 114 | |
| 115 | func previewControllerDidDismiss(_ controller: QLPreviewController) { |
| 116 | transitionView?.removeFromSuperview() |
| 117 | transitionView = nil |
| 118 | preview = nil |
| 119 | presenting = false |
| 120 | current = nil |
| 121 | onClose() |
| 122 | } |
| 123 | } |
| 124 | |
| 125 | // Quick Look reads the file by URL. A nil URL can't reach here: the data |
| 126 | // source reports 0 items until an item exists. |
| 127 | private final class PreviewFile: NSObject, QLPreviewItem { |
| 128 | let previewItemURL: URL? |
| 129 | init(url: URL?) { previewItemURL = url } |
| 130 | } |
| 131 | } |
| 132 | |
| 133 | // 🤖 Boots Quick Look's out-of-process render service ONCE per launch so the |
| 134 | // first real preview doesn't flash its cold-start chrome. Presents a preview of |
| 135 | // a throwaway file on a 1pt, fully-transparent window behind everything, then |
| 136 | // tears it (and the file) straight back down — the user never sees it, but the |
| 137 | // service is warm by the time they tap a photo. |
| 138 | @MainActor |
| 139 | enum QuickLookWarmup { |
| 140 | private static var done = false |
| 141 | private static var window: UIWindow? |
| 142 | private static var source: Source? |
| 143 | |
| 144 | static func warmIfNeeded(scene: UIWindowScene?) { |
| 145 | guard !done, let scene else { return } |
| 146 | done = true |
| 147 | guard let url = try? stageDummy() else { return } |
| 148 | let src = Source(url: url) |
| 149 | source = src |
| 150 | |
| 151 | let w = UIWindow(windowScene: scene) |
| 152 | w.frame = CGRect(x: 0, y: 0, width: 1, height: 1) |
| 153 | w.windowLevel = UIWindow.Level(rawValue: -1000) // behind the real UI |
| 154 | w.alpha = 0.01 // effectively invisible |
| 155 | w.isHidden = false |
| 156 | let root = UIViewController() |
| 157 | w.rootViewController = root |
| 158 | window = w |
| 159 | |
| 160 | let ql = QLPreviewController() |
| 161 | ql.dataSource = src |
| 162 | root.present(ql, animated: false) { |
| 163 | root.dismiss(animated: false) { |
| 164 | window?.isHidden = true |
| 165 | window = nil |
| 166 | source = nil |
| 167 | try? FileManager.default.removeItem(at: url.deletingLastPathComponent()) |
| 168 | } |
| 169 | } |
| 170 | } |
| 171 | |
| 172 | private static func stageDummy() throws -> URL { |
| 173 | let dir = FileManager.default.temporaryDirectory |
| 174 | .appendingPathComponent("ql-warm-\(UUID().uuidString)", isDirectory: true) |
| 175 | try FileManager.default.createDirectory(at: dir, withIntermediateDirectories: true) |
| 176 | let url = dir.appendingPathComponent("warm.txt") |
| 177 | try Data(" ".utf8).write(to: url) |
| 178 | return url |
| 179 | } |
| 180 | |
| 181 | final class Source: NSObject, QLPreviewControllerDataSource { |
| 182 | private let item: Item |
| 183 | init(url: URL) { item = Item(url: url) } |
| 184 | func numberOfPreviewItems(in controller: QLPreviewController) -> Int { 1 } |
| 185 | func previewController(_ controller: QLPreviewController, |
| 186 | previewItemAt index: Int) -> QLPreviewItem { item } |
| 187 | } |
| 188 | |
| 189 | private final class Item: NSObject, QLPreviewItem { |
| 190 | let previewItemURL: URL? |
| 191 | init(url: URL) { previewItemURL = url } |
| 192 | } |
| 193 | } |
| 194 | |
amadan