Reorganize and rename image assets (#712)

- organize image assets into subdirs named after pages to make it clear
  where each image is used
- use more generic and flavor-friendly asset names that don't assume
  the content (e.g. "mascot" -> "logo") of the vanilla image assets

Ref: #700
Ref: ubuntu-mate/ubuntu-mate-installer#1

packages/ubuntu_desktop_installer/lib/installer.dart

@@ -178,7 +178,7 @@ class _UbuntuDesktopInstallerLoadingPage extends StatelessWidget {
           const SizedBox(width: 20),
           Expanded(
             child: SvgPicture.asset(
-              'assets/mascot_white.svg',
+              'assets/welcome/logo.svg',
               height: height / 4,
               color: Theme.of(context).primaryColor,
             ),

packages/ubuntu_desktop_installer/lib/pages/choose_your_look_page.dart

@@ -29,7 +29,7 @@ class ChooseYourLookPage extends StatelessWidget {
             children: [
               _ThemeOptionCard(
                 width: width / 3,
-                assetName: 'assets/Theme_thumbnails-Light.png',
+                assetName: 'assets/choose_your_look/light-theme.png',
                 selected: Theme.of(context).brightness == Brightness.light,
                 onTap: () {
                   settings.applyTheme(Brightness.light);
@@ -41,7 +41,7 @@ class ChooseYourLookPage extends StatelessWidget {
               ),
               _ThemeOptionCard(
                 width: width / 3,
-                assetName: 'assets/Theme_thumbnails-Dark.png',
+                assetName: 'assets/choose_your_look/dark-theme.png',
                 selected: Theme.of(context).brightness == Brightness.dark,
                 onTap: () {
                   settings.applyTheme(Brightness.dark);

packages/ubuntu_desktop_installer/lib/pages/installation_complete/installation_complete_page.dart

@@ -42,7 +42,7 @@ class InstallationCompletePage extends StatelessWidget {
               child: const CircleAvatar(
                 radius: 80,
                 backgroundImage: AssetImage(
-                  'assets/version.png',
+                  'assets/installation_complete/logo.png',
                 ),
               ),
             ),

packages/ubuntu_desktop_installer/lib/pages/installation_slides/installation_slides_model.dart

@@ -78,7 +78,7 @@ class InstallationSlidesModel extends ChangeNotifier with SystemShutdown {
   /// loading slide images
   Future<void> precacheSlideImages(BuildContext context) {
     final assets = _resolveAssetsDirectory();
-    return Directory('$assets/assets/slides')
+    return Directory('$assets/assets/installation_slides')
         .list(recursive: true)
         .forEach((slide) {
       if (slide is File) {

packages/ubuntu_desktop_installer/lib/pages/select_guided_storage/select_guided_storage_page.dart

@@ -93,7 +93,7 @@ class _SelectGuidedStoragePageState extends State<SelectGuidedStoragePage> {
                 mainAxisSize: MainAxisSize.min,
                 children: <Widget>[
                   SvgPicture.asset(
-                    'assets/cof_orange_hex.svg',
+                    'assets/select_guided_storage/ubuntu.svg',
                     width: 48,
                     height: 48,
                   ),

packages/ubuntu_desktop_installer/lib/pages/try_or_install/try_or_install_page.dart

@@ -40,7 +40,8 @@ class TryOrInstallPageState extends State<TryOrInstallPage> {
           Expanded(
             child: OptionCard(
               selected: model.option == Option.repairUbuntu,
-              image: FlavorImage.asset('assets/repair-wrench.png'),
+              image:
+                  FlavorImage.asset('assets/try_or_install/repair-wrench.png'),
               title: Text(lang.repairInstallation),
               body: Text(lang.repairInstallationDescription),
               onSelected: () => model.selectOption(Option.repairUbuntu),
@@ -50,7 +51,8 @@ class TryOrInstallPageState extends State<TryOrInstallPage> {
           Expanded(
             child: OptionCard(
               selected: model.option == Option.tryUbuntu,
-              image: FlavorImage.asset('assets/steering-wheel.png'),
+              image:
+                  FlavorImage.asset('assets/try_or_install/steering-wheel.png'),
               title: Text(lang.tryUbuntu(flavor.name)),
               body: Text(lang.tryUbuntuDescription(flavor.name)),
               onSelected: () => model.selectOption(Option.tryUbuntu),
@@ -60,7 +62,7 @@ class TryOrInstallPageState extends State<TryOrInstallPage> {
           Expanded(
             child: OptionCard(
               selected: model.option == Option.installUbuntu,
-              image: FlavorImage.asset('assets/hard-drive.png'),
+              image: FlavorImage.asset('assets/try_or_install/hard-drive.png'),
               title: Text(lang.installUbuntu(flavor.name)),
               body: Text(lang.installUbuntuDescription(flavor.name)),
               onSelected: () => model.selectOption(Option.installUbuntu),

packages/ubuntu_desktop_installer/lib/pages/turn_off_bitlocker/turn_off_bitlocker_page.dart

@@ -39,7 +39,7 @@ class TurnOffBitLockerPage extends StatelessWidget {
             onLinkTap: (url, _, __, ___) => launchUrl(url!),
           ),
           const SizedBox(height: 60),
-          SvgPicture.asset('assets/qrbitlocker.svg')
+          SvgPicture.asset('assets/turn_off_bitlocker/qr-code.svg')
         ],
       ),
       actions: [

packages/ubuntu_desktop_installer/lib/pages/turn_off_rst/turn_off_rst_page.dart

@@ -44,7 +44,7 @@ class TurnOffRSTPage extends StatelessWidget {
             ),
             const SizedBox(height: 60),
             SvgPicture.asset(
-              'assets/rst.svg',
+              'assets/turn_off_rst/qr-code.svg',
               color: Theme.of(context).textTheme.bodyText1!.color,
             ),
           ],

packages/ubuntu_desktop_installer/lib/pages/welcome/welcome_page.dart

@@ -87,7 +87,7 @@ class _WelcomePageState extends State<WelcomePage> {
             const SizedBox(width: 20),
             Expanded(
               child: SvgPicture.asset(
-                'assets/mascot_white.svg',
+                'assets/welcome/logo.svg',
                 height: height / 4,
                 color: Theme.of(context).primaryColor,
               ),

packages/ubuntu_desktop_installer/lib/slides/default_slides.dart

@@ -13,9 +13,10 @@ const _kInsets = EdgeInsets.fromLTRB(72, 56, 48, 24);
 const _kSmallSpacing = 8.0;
 const _kLargeSpacing = 16.0;
 
-String _slideAsset(String name) => 'assets/slides/$name.png';
-String _slideIcon(String name) => 'assets/slides/icons/$name.png';
-String _slideScreenshot(String name) => 'assets/slides/screenshots/$name.png';
+String _slideAsset(String name) => 'assets/installation_slides/$name.png';
+String _slideIcon(String name) => 'assets/installation_slides/icons/$name.png';
+String _slideScreenshot(String name) =>
+    'assets/installation_slides/screenshots/$name.png';
 
 /// The list of default installation slides.
 final defaultSlides = <Slide>[

packages/ubuntu_desktop_installer/pubspec.yaml

@@ -66,6 +66,13 @@ flutter:
   uses-material-design: true
   assets:
     - assets/
-    - assets/slides/
-    - assets/slides/icons/
-    - assets/slides/screenshots/
+    - assets/choose_your_look/
+    - assets/installation_complete/
+    - assets/installation_slides/
+    - assets/installation_slides/icons/
+    - assets/installation_slides/screenshots/
+    - assets/select_guided_storage/
+    - assets/try_or_install/
+    - assets/turn_off_bitlocker/
+    - assets/turn_off_rst/
+    - assets/welcome/

packages/ubuntu_desktop_installer/test/choose_your_look/choose_your_look_page_test.dart

@@ -24,15 +24,15 @@ void main() {
 
     final lightOptionCard = find.widgetWithImage(
       YaruSelectableContainer,
-      AssetImage('assets/Theme_thumbnails-Light.png'),
+      AssetImage('assets/choose_your_look/light-theme.png'),
     );
     expect(lightOptionCard, findsOneWidget);
     await tester.tap(lightOptionCard);
     verify(settings.applyTheme(Brightness.light));
 
     final darkOptionCard = find.widgetWithImage(
       YaruSelectableContainer,
-      AssetImage('assets/Theme_thumbnails-Dark.png'),
+      AssetImage('assets/choose_your_look/dark-theme.png'),
     );
     expect(darkOptionCard, findsOneWidget);
     await tester.tap(darkOptionCard);