wip

frontend/sync-client/src/sync-operations/file-manifest.ts

@@ -0,0 +1,69 @@
+import type { FileManifestEntries } from "../types/file-manifest-entries";
+import {
+    allocatePortablePath,
+    validatePortablePaths
+} from "../utils/portable-path";
+
+export function validateFileManifest(entries: FileManifestEntries): void {
+    validatePortablePaths(Object.values(entries));
+}
+
+export function sameFileManifest(
+    a: FileManifestEntries,
+    b: FileManifestEntries
+): boolean {
+    return (
+        Object.keys(a).length === Object.keys(b).length &&
+        Object.keys(a).every((id) => a[id] === b[id])
+    );
+}
+
+export function resolvePaths(
+    proposed: FileManifestEntries,
+    remote: FileManifestEntries,
+    protectedIds: readonly string[] = [],
+    reservedPaths: readonly string[] = []
+): FileManifestEntries {
+    const result: FileManifestEntries = {};
+    for (const id of protectedIds)
+        if (proposed[id] !== undefined) result[id] = proposed[id];
+    const occupied = { ...result };
+    for (const [index, path] of reservedPaths.entries())
+        if (!Object.values(result).includes(path))
+            occupied[`reserved-${index}`] = path;
+    const ids = Object.keys(proposed).sort(
+        (a, b) =>
+            Number(remote[b] === proposed[b]) -
+                Number(remote[a] === proposed[a]) ||
+            (a < b ? -1 : a > b ? 1 : 0)
+    );
+    for (const id of ids.filter(
+        (candidate) => result[candidate] === undefined
+    )) {
+        result[id] = allocatePortablePath(proposed[id], id, occupied);
+        occupied[id] = result[id];
+    }
+    return result;
+}
+
+export function mergeFileManifests(
+    base: FileManifestEntries,
+    local: FileManifestEntries,
+    remote: FileManifestEntries
+): FileManifestEntries {
+    const proposed: FileManifestEntries = {};
+    for (const id of new Set([
+        ...Object.keys(base),
+        ...Object.keys(local),
+        ...Object.keys(remote)
+    ])) {
+        const path =
+            local[id] === base[id]
+                ? remote[id]
+                : remote[id] === base[id]
+                  ? local[id]
+                  : remote[id];
+        if (path !== undefined) proposed[id] = path;
+    }
+    return resolvePaths(proposed, remote);
+}