wip(app): i18n

2 files changed, 148 insertions, 8 deletions

diff --git a/specs/06-app-i18n-audit.md b/specs/06-app-i18n-audit.md
index c933d842d..c4c735226 100644
--- a/specs/06-app-i18n-audit.md
+++ b/specs/06-app-i18n-audit.md
@@ -137,9 +137,9 @@ Completed (2026-01-20):
 
 File: `packages/app/src/components/dialog-select-server.tsx`
 
-- Placeholder: `http://localhost:4096`
+Completed (2026-01-20):
 
-This is an example URL; you may choose to keep it as-is even after translating surrounding labels.
+- Moved the placeholder example URL behind `dialog.server.add.placeholder` (value unchanged).
 
 ## Medium Priority: Context Modules
 
@@ -193,14 +193,14 @@ Completed (2026-01-20):
 
 File: `packages/app/src/entry.tsx`
 
-- Dev-only error string: "Root element not found..."
+Completed (2026-01-20):
 
-This is only thrown in DEV and is more of a developer diagnostic. Optional to translate.
+- Localized the DEV-only root mount error via `error.dev.rootNotFound`.
+- Selected locale using `navigator.languages` to match the app’s default detection.
 
 ## Prioritized Implementation Plan
 
-1. Optional: `packages/app/src/components/dialog-select-server.tsx` placeholder example URL.
-2. Optional: `packages/app/src/entry.tsx` dev-only root mount error.
+No remaining work in `packages/app/` as of 2026-01-20.
 
 ## Suggested Key Naming Conventions
 
@@ -223,10 +223,10 @@ Pages:
 - (none)
 
 Components:
-- `packages/app/src/components/dialog-select-server.tsx` (optional URL placeholder)
+- (none)
 
 Context:
 - (none)
 
 Utils:
-- `packages/app/src/entry.tsx` (dev-only)
+- (none)
diff --git a/specs/07-ui-i18n-audit.md b/specs/07-ui-i18n-audit.md
new file mode 100644
index 000000000..280818c00
--- /dev/null
+++ b/specs/07-ui-i18n-audit.md
@@ -0,0 +1,140 @@
+# UI i18n Audit (Remaining Work)
+
+Scope: `packages/ui/` (and consumers: `packages/app/`, `packages/enterprise/`)
+
+Date: 2026-01-20
+
+This report documents the remaining user-facing strings in `packages/ui/src` that are still hardcoded (not routed through a translation function), and proposes an i18n architecture that works long-term across multiple packages.
+
+## Current State
+
+- `packages/app/` already has i18n via `useLanguage().t("...")` with dictionaries in `packages/app/src/i18n/en.ts` and `packages/app/src/i18n/zh.ts`.
+- `packages/ui/` is a shared component library used by:
+  - `packages/app/src/pages/session.tsx` (Session UI)
+  - `packages/enterprise/src/routes/share/[shareID].tsx` (shared session rendering)
+- `packages/ui/` currently has **hardcoded English UI copy** in several components (notably `session-turn.tsx`, `session-review.tsx`, `message-part.tsx`).
+- `packages/enterprise/` does not currently have an i18n system, so any i18n approach must be usable without depending on `packages/app/`.
+
+## Decision: How We Should Add i18n To `@opencode-ai/ui`
+
+Introduce a small, app-agnostic i18n interface in `packages/ui/` and keep UI-owned strings in UI-owned dictionaries.
+
+Why this is the best long-term shape:
+
+- Keeps dependency direction clean: `packages/enterprise/` (and any future consumer) can translate UI without importing `packages/app/` dictionaries.
+- Avoids prop-drilling strings through shared components.
+- Allows each package to own its strings while still rendering a single, coherent locale in the product.
+
+### Proposed Architecture
+
+1) **UI provides an i18n context (no persistence)**
+
+- Add `packages/ui/src/context/i18n.tsx`:
+  - Exports `I18nProvider` and `useI18n()`.
+  - Context value includes:
+    - `t(key, params?)` translation function (template interpolation supported by the consumer).
+    - `locale()` accessor for locale-sensitive formatting (Luxon/Intl).
+  - Context should have a safe default (English) so UI components can render even if a consumer forgets the provider.
+
+2) **UI owns UI strings (dictionaries live in UI)**
+
+- Add `packages/ui/src/i18n/en.ts` and `packages/ui/src/i18n/zh.ts`.
+- Export them from `@opencode-ai/ui` via `packages/ui/package.json` exports (e.g. `"./i18n/*": "./src/i18n/*.ts"`).
+- Use a clear namespace prefix for all UI keys to avoid collisions:
+  - Recommended: `ui.*` (e.g. `ui.sessionReview.title`).
+
+3) **Consumers merge dictionaries and provide `t`/`locale` once**
+
+- `packages/app/`:
+  - Keep `packages/app/src/context/language.tsx` as the source of truth for locale selection/persistence.
+  - Extend it to merge UI dictionaries into its translation table.
+  - Add a tiny bridge provider in `packages/app/src/app.tsx` to feed `useLanguage()` into `@opencode-ai/ui`'s `I18nProvider`.
+
+- `packages/enterprise/`:
+  - Add a lightweight locale detector (similar to `packages/app/src/context/language.tsx`), likely based on `Accept-Language` on the server and/or `navigator.languages` on the client.
+  - Merge `@opencode-ai/ui` dictionaries and (optionally) enterprise-local dictionaries.
+  - Wrap the share route in `I18nProvider`.
+
+### Key Naming Conventions (UI)
+
+- Prefer component + semantic grouping:
+  - `ui.sessionReview.title`
+  - `ui.sessionReview.diffStyle.unified`
+  - `ui.sessionReview.diffStyle.split`
+  - `ui.sessionReview.expandAll`
+  - `ui.sessionReview.collapseAll`
+
+- For `SessionTurn`:
+  - `ui.sessionTurn.steps.show`
+  - `ui.sessionTurn.steps.hide`
+  - `ui.sessionTurn.summary.response`
+  - `ui.sessionTurn.diff.more` (use templating: `Show more changes ({{count}})`)
+  - `ui.sessionTurn.retry.retrying` / `ui.sessionTurn.retry.inSeconds` / etc (avoid string concatenation that is English-order dependent)
+  - Status text:
+    - `ui.sessionTurn.status.delegating`
+    - `ui.sessionTurn.status.planning`
+    - `ui.sessionTurn.status.gatheringContext`
+    - `ui.sessionTurn.status.searchingCode`
+    - `ui.sessionTurn.status.searchingWeb`
+    - `ui.sessionTurn.status.makingEdits`
+    - `ui.sessionTurn.status.runningCommands`
+    - `ui.sessionTurn.status.thinking`
+    - `ui.sessionTurn.status.thinkingWithTopic` (template: `Thinking - {{topic}}`)
+    - `ui.sessionTurn.status.gatheringThoughts`
+    - `ui.sessionTurn.status.consideringNextSteps` (fallback)
+
+## Locale-Sensitive Formatting (UI)
+
+`SessionTurn` currently formats durations via Luxon `Interval.toDuration(...).toHuman(...)` without an explicit locale.
+
+When i18n is added:
+
+- Use `useI18n().locale()` and pass locale explicitly:
+  - Luxon: `duration.toHuman({ locale: locale(), ... })` (or set `.setLocale(locale())` where applicable).
+  - Intl numbers/currency (if added later): `new Intl.NumberFormat(locale(), ...)`.
+
+## Initial Hardcoded Strings (Audit Findings)
+
+These are the highest-impact UI surfaces to translate first.
+
+### 1) `packages/ui/src/components/session-review.tsx`
+
+- `Session changes`
+- `Unified` / `Split`
+- `Collapse all` / `Expand all`
+
+### 2) `packages/ui/src/components/session-turn.tsx`
+
+- Tool/task status strings (e.g. `Delegating work`, `Searching the codebase`)
+- Steps toggle labels: `Show steps` / `Hide steps`
+- Summary section title: `Response`
+- Pagination CTA: `Show more changes ({{count}})`
+
+### 3) `packages/ui/src/components/message-part.tsx`
+
+Examples (non-exhaustive):
+
+- `Error`
+- `Edit`
+- `Write`
+- `Type your own answer`
+- `Review your answers`
+
+## Prioritized Implementation Plan
+
+1. Add `@opencode-ai/ui` i18n context (`packages/ui/src/context/i18n.tsx`) + export it.
+2. Add UI dictionaries (`packages/ui/src/i18n/en.ts`, `packages/ui/src/i18n/zh.ts`) + export them.
+3. Wire `I18nProvider` into:
+   - `packages/app/src/app.tsx`
+   - `packages/enterprise/src/routes/share/[shareID].tsx`
+4. Convert `packages/ui/src/components/session-review.tsx` and `packages/ui/src/components/session-turn.tsx` to use `useI18n().t(...)`.
+5. Convert `packages/ui/src/components/message-part.tsx`.
+6. Do a full `packages/ui/src/components` + `packages/ui/src/context` audit for additional hardcoded copy.
+
+## Notes / Risks
+
+- **SSR:** Enterprise share pages render on the server. Ensure the i18n provider works in SSR and does not assume `window`/`navigator`.
+- **Key collisions:** Use a consistent `ui.*` prefix to avoid clashing with app keys.
+- **Fallback behavior:** Decide whether missing keys should:
+  - fall back to English, or
+  - render the key (useful for catching missing translations).