2 files changed, 185 insertions, 0 deletions
diff --git a/src/data/composite/things/track/index.js b/src/data/composite/things/track/index.js
index c200df19..db982ea7 100644
--- a/src/data/composite/things/track/index.js
+++ b/src/data/composite/things/track/index.js
@@ -1,2 +1,3 @@
 export {default as inheritContributionListFromMainRelease} from './inheritContributionListFromMainRelease.js';
 export {default as inheritFromMainRelease} from './inheritFromMainRelease.js';
+export {default as withDirectorySuffixes} from './withDirectorySuffixes.js';
diff --git a/src/data/composite/things/track/withDirectorySuffixes.js b/src/data/composite/things/track/withDirectorySuffixes.js
new file mode 100644
index 00000000..87a737db
--- /dev/null
+++ b/src/data/composite/things/track/withDirectorySuffixes.js
@@ -0,0 +1,184 @@
+import {input, templateCompositeFrom} from '#composite';
+import {getKebabCase} from '#wiki-data';
+
+import {withPropertiesFromObject} from '#composite/data';
+
+export default templateCompositeFrom({
+  annotation: `withDirectorySuffixes`,
+
+  inputs: {
+    from: input({
+      defaultDependency: '_suffixDirectory',
+      acceptsNull: true,
+    }),
+  },
+
+  // sorry these are in noun form (dies)
+  outputs: ['#directorySuffix', '#directorySuffixWithinAlbum'],
+
+  steps: () =>  [
+    withPropertiesFromObject({
+      object: 'trackSection',
+      properties: input.value([
+        'suffixTrackDirectoriesByDefault',
+        'directorySuffixForTracks',
+      ]),
+    }),
+
+    {
+      dependencies: [
+        input('from'),
+        '#trackSection.suffixTrackDirectoriesByDefault',
+        '#trackSection.directorySuffixForTracks',
+      ],
+
+      compute(continuation, {
+        [input('from')]:
+          suffixDirectory,
+
+        ['#trackSection.suffixTrackDirectoriesByDefault']:
+          suffixTrackDirectoriesByDefault,
+
+        ['#trackSection.directorySuffixForTracks']:
+          directorySuffixForTracks,
+      }) {
+        // All conditions in this chunk process explicitly set values for
+        // the actual update value - that is, everything EXCEPT true or null,
+        // which both pass through to conditional "defaults".
+        // (True and null aren't quite equal, but the difference only matters
+        //  at the very end.)
+
+        if (suffixDirectory === 'album') {
+          return continuation.raiseOutput({
+            ['#directorySuffix']: directorySuffixForTracks,
+            ['#directorySuffixWithinAlbum']: null,
+          });
+        }
+
+        if (typeof suffixDirectory === 'string') {
+          return continuation.raiseOutput({
+            ['#directorySuffix']: suffixDirectory,
+            ['#directorySuffixWithinAlbum']: suffixDirectory,
+          });
+        }
+
+        if (suffixDirectory === false) {
+          return continuation.raiseOutput({
+            ['#directorySuffix']: null,
+            ['#directorySuffixWithinAlbum']: null,
+          });
+        }
+
+        if (Array.isArray(suffixDirectory)) {
+          const parts1 =
+            suffixDirectory
+              .map(item =>
+                (item === 'album'
+                  ? directorySuffixForTracks
+                  : item));
+
+          const parts2 =
+            suffixDirectory
+              .map(item =>
+                (item === 'album'
+                  ? null
+                  : item))
+              .filter(Boolean);
+
+          return continuation.raiseOutput({
+            ['#directorySuffix']: parts1.join('-'),
+            ['#directorySuffixWithinAlbum']: parts2.join('-'),
+          });
+        }
+
+        // It's true or null - just continue.
+        return continuation();
+      },
+    },
+
+    {
+      dependencies: [
+        '#trackSection.suffixTrackDirectoriesByDefault',
+        '#trackSection.directorySuffixForTracks',
+      ],
+
+      compute(continuation, {
+        ['#trackSection.suffixTrackDirectoriesByDefault']:
+          suffixTrackDirectoriesByDefault,
+
+        ['#trackSection.directorySuffixForTracks']:
+          directorySuffixForTracks,
+      }) {
+        if (suffixTrackDirectoriesByDefault === true) {
+          return continuation.raiseOutput({
+            ['#directorySuffix']: directorySuffixForTracks,
+            ['#directorySuffixWithinAlbum']: null,
+          });
+        }
+
+        return continuation();
+      },
+    },
+
+    {
+      dependencies: [
+        '_nameDetail',
+         'nameDetailAcrossWiki',
+
+        '#trackSection.directorySuffixForTracks',
+      ],
+
+      compute(continuation, {
+        ['_nameDetail']: nameDetail,
+        [ 'nameDetailAcrossWiki']: nameDetailAcrossWiki,
+
+        ['#trackSection.directorySuffixForTracks']:
+          directorySuffixForTracks,
+      }) {
+        if (nameDetail === 'album') {
+          return continuation.raiseOutput({
+            ['#directorySuffix']: directorySuffixForTracks,
+            ['#directorySuffixWithinAlbum']: directorySuffixForTracks,
+          });
+        }
+
+        if (nameDetailAcrossWiki) {
+          const kebab = getKebabCase(nameDetailAcrossWiki);
+
+          return continuation.raiseOutput({
+            ['#directorySuffix']: kebab,
+            ['#directorySuffixWithinAlbum']: kebab,
+          });
+        }
+
+        return continuation();
+      },
+    },
+
+    // Ultimately, if no conditions above exposed a more particular value,
+    // now we can FINALLY differentiate between true and null.
+    {
+      dependencies: [
+        input('from'),
+        '#trackSection.directorySuffixForTracks',
+      ],
+
+      compute: (continuation, {
+        [input('from')]:
+          suffixDirectory,
+
+        ['#trackSection.directorySuffixForTracks']:
+          directorySuffixForTracks,
+      }) =>
+        (suffixDirectory === true
+          ? continuation({
+              ['#directorySuffix']: directorySuffixForTracks,
+              ['#directorySuffixWithinAlbum']: null,
+            })
+          : continuation({
+              ['#directorySuffix']: null,
+              ['#directorySuffixWithinAlbum']: null,
+            })),
+    },
+  ],
+});