1 files changed, 49 insertions, 0 deletions
diff --git a/packages/app/src/utils/diffs.ts b/packages/app/src/utils/diffs.ts
new file mode 100644
index 000000000..0cb2504fb
--- /dev/null
+++ b/packages/app/src/utils/diffs.ts
@@ -0,0 +1,49 @@
+import type { SnapshotFileDiff, VcsFileDiff } from "@opencode-ai/sdk/v2"
+import type { Message } from "@opencode-ai/sdk/v2/client"
+
+type Diff = SnapshotFileDiff | VcsFileDiff
+
+function diff(value: unknown): value is Diff {
+  if (!value || typeof value !== "object" || Array.isArray(value)) return false
+  if (!("file" in value) || typeof value.file !== "string") return false
+  if (!("patch" in value) || typeof value.patch !== "string") return false
+  if (!("additions" in value) || typeof value.additions !== "number") return false
+  if (!("deletions" in value) || typeof value.deletions !== "number") return false
+  if (!("status" in value) || value.status === undefined) return true
+  return value.status === "added" || value.status === "deleted" || value.status === "modified"
+}
+
+function object(value: unknown): value is Record<string, unknown> {
+  return !!value && typeof value === "object" && !Array.isArray(value)
+}
+
+export function diffs(value: unknown): Diff[] {
+  if (Array.isArray(value) && value.every(diff)) return value
+  if (Array.isArray(value)) return value.filter(diff)
+  if (diff(value)) return [value]
+  if (!object(value)) return []
+  return Object.values(value).filter(diff)
+}
+
+export function message(value: Message): Message {
+  if (value.role !== "user") return value
+
+  const raw = value.summary as unknown
+  if (raw === undefined) return value
+  if (!object(raw)) return { ...value, summary: undefined }
+
+  const title = typeof raw.title === "string" ? raw.title : undefined
+  const body = typeof raw.body === "string" ? raw.body : undefined
+  const next = diffs(raw.diffs)
+
+  if (title === raw.title && body === raw.body && next === raw.diffs) return value
+
+  return {
+    ...value,
+    summary: {
+      ...(title === undefined ? {} : { title }),
+      ...(body === undefined ? {} : { body }),
+      diffs: next,
+    },
+  }
+}