feat(app): better diff/code comments (#14621)

Co-authored-by: adamelmore <2363879+adamdottv@users.noreply.github.com>
Co-authored-by: David Hill <iamdavidhill@gmail.com>

packages/app/src/utils/comment-note.ts

@@ -0,0 +1,88 @@
+import type { FileSelection } from "@/context/file"
+
+export type PromptComment = {
+  path: string
+  selection?: FileSelection
+  comment: string
+  preview?: string
+  origin?: "review" | "file"
+}
+
+function selection(selection: unknown) {
+  if (!selection || typeof selection !== "object") return undefined
+  const startLine = Number((selection as FileSelection).startLine)
+  const startChar = Number((selection as FileSelection).startChar)
+  const endLine = Number((selection as FileSelection).endLine)
+  const endChar = Number((selection as FileSelection).endChar)
+  if (![startLine, startChar, endLine, endChar].every(Number.isFinite)) return undefined
+  return {
+    startLine,
+    startChar,
+    endLine,
+    endChar,
+  } satisfies FileSelection
+}
+
+export function createCommentMetadata(input: PromptComment) {
+  return {
+    opencodeComment: {
+      path: input.path,
+      selection: input.selection,
+      comment: input.comment,
+      preview: input.preview,
+      origin: input.origin,
+    },
+  }
+}
+
+export function readCommentMetadata(value: unknown) {
+  if (!value || typeof value !== "object") return
+  const meta = (value as { opencodeComment?: unknown }).opencodeComment
+  if (!meta || typeof meta !== "object") return
+  const path = (meta as { path?: unknown }).path
+  const comment = (meta as { comment?: unknown }).comment
+  if (typeof path !== "string" || typeof comment !== "string") return
+  const preview = (meta as { preview?: unknown }).preview
+  const origin = (meta as { origin?: unknown }).origin
+  return {
+    path,
+    selection: selection((meta as { selection?: unknown }).selection),
+    comment,
+    preview: typeof preview === "string" ? preview : undefined,
+    origin: origin === "review" || origin === "file" ? origin : undefined,
+  } satisfies PromptComment
+}
+
+export function formatCommentNote(input: { path: string; selection?: FileSelection; comment: string }) {
+  const start = input.selection ? Math.min(input.selection.startLine, input.selection.endLine) : undefined
+  const end = input.selection ? Math.max(input.selection.startLine, input.selection.endLine) : undefined
+  const range =
+    start === undefined || end === undefined
+      ? "this file"
+      : start === end
+        ? `line ${start}`
+        : `lines ${start} through ${end}`
+  return `The user made the following comment regarding ${range} of ${input.path}: ${input.comment}`
+}
+
+export function parseCommentNote(text: string) {
+  const match = text.match(
+    /^The user made the following comment regarding (this file|line (\d+)|lines (\d+) through (\d+)) of (.+?): ([\s\S]+)$/,
+  )
+  if (!match) return
+  const start = match[2] ? Number(match[2]) : match[3] ? Number(match[3]) : undefined
+  const end = match[2] ? Number(match[2]) : match[4] ? Number(match[4]) : undefined
+  return {
+    path: match[5],
+    selection:
+      start !== undefined && end !== undefined
+        ? {
+            startLine: start,
+            startChar: 0,
+            endLine: end,
+            endChar: 0,
+          }
+        : undefined,
+    comment: match[6],
+  } satisfies PromptComment
+}