# Script-editor `ctx` tag-completion correctness + truthfulness — Implementation Plan

> **For Claude:** REQUIRED SUB-SKILL: Use superpowers-extended-cc:subagent-driven-development to implement this plan task-by-task.

**Goal:** Make the Monaco script-editor's tag-path completion/hover fire only on `ctx.` receivers (matching the runtime harvest) and stop advertising `ctx.SetVirtualTag(...)` cross-tag writes as if they work (they are a no-op in the live single-tag engine).

**Architecture:** Both `ScriptAnalysisService.CompleteAsync` and `.Hover` route through one private syntactic gate, `TryGetTagPathLiteral`. Add a receiver guard (`ctx` identifier) there, and surface which method matched so `Hover` can append a truthful note for `SetVirtualTag`. AdminUI-only; no runtime/Commons/proto/EF change; no bUnit.

**Tech Stack:** C# / .NET 10, Roslyn syntax API (`Microsoft.CodeAnalysis.CSharp`), xUnit + Shouldly. Design: `docs/plans/2026-06-18-script-editor-ctx-completions-design.md` (committed `e84f7a6e`).

---

### Task 1: Receiver-type guard + truthful `SetVirtualTag` hover

**Classification:** small
**Estimated implement time:** ~5 min
**Parallelizable with:** none

**Files:**
- Modify: `src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/ScriptAnalysis/ScriptAnalysisService.cs`
  - `TryGetTagPathLiteral` (currently ~line 213–229): add the `ctx` receiver guard + a new `out bool isSetVirtualTag`.
  - `CompleteAsync` call site (~line 164): pass `out _` for the new param.
  - `Hover` call site (~line 255) + the `tagMd` build (~line 268–272): pass `out var isSetVirtualTag`; append the single-tag-drop note when it is true.
- Test: `tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests/ScriptAnalysis/CtxCompletionGuardTests.cs` (create)

(The `Files:` block IS the contract — do not touch the runtime, Commons, or the catalog. `TryGetTagPathLiteral` is purely syntactic; keep it that way — do NOT introduce a semantic/type check on the receiver. The `ctx` identifier match is intentional: it mirrors `Commons/Types/EquipmentScriptPaths.GetTagRefRegex` = `ctx\s*\.\s*(?:GetTag|SetVirtualTag)`, so the editor accepts exactly what `Phase7Composer` harvests.)

**Context — current gate (verbatim):**
```csharp
private static bool TryGetTagPathLiteral(SyntaxToken token, out string prefix)
{
    prefix = "";
    var literal = token.Parent as LiteralExpressionSyntax
        ?? token.GetPreviousToken().Parent as LiteralExpressionSyntax;
    if (literal is null || !literal.IsKind(SyntaxKind.StringLiteralExpression)) return false;
    if (literal.Parent is not ArgumentSyntax arg) return false;
    if (arg.Parent is not ArgumentListSyntax argList) return false;
    if (argList.Parent is not InvocationExpressionSyntax inv) return false;
    if (inv.Expression is not MemberAccessExpressionSyntax ma) return false;
    var method = ma.Name.Identifier.ValueText;
    if (method is not ("GetTag" or "SetVirtualTag")) return false;
    // only the FIRST argument is the path
    if (argList.Arguments.Count > 0 && argList.Arguments[0] != arg) return false;
    prefix = literal.Token.ValueText ?? "";
    return true;
}
```

The two callers today:
- `CompleteAsync`: `if (_catalog != null && TryGetTagPathLiteral(token, out var pathPrefix))`
- `Hover`: `if (_catalog is not null && TryGetTagPathLiteral(token, out var tagPath) && !string.IsNullOrEmpty(tagPath))`, which then builds:
```csharp
var info = await _catalog.GetTagInfoAsync(tagPath, CancellationToken.None);
var tagMd = info is null
    ? $"**Tag path** `{Code(tagPath)}`\n\n⚠ Not a known configured tag path."
    : $"**Tag path** `{Code(info.Path)}`\n\n{info.Kind} · Type **{info.DataType}**"
        + (info.DriverInstanceId is null ? "" : $" · Driver `{Code(info.DriverInstanceId)}`");
return new HoverResponse(tagMd);
```

**Step 1: Write the failing tests**

Create `tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests/ScriptAnalysis/CtxCompletionGuardTests.cs`:

```csharp
using System.Threading;
using System.Threading.Tasks;
using Shouldly;
using Xunit;
using ZB.MOM.WW.OtOpcUa.AdminUI.ScriptAnalysis;

namespace ZB.MOM.WW.OtOpcUa.AdminUI.Tests.ScriptAnalysis;

public sealed class CtxCompletionGuardTests
{
    // Catalog that always offers one distinctive path + resolves a vtag, so the tag-path branch is
    // observable without a DB. The path "Line1.Speed" never appears in C# scoped/dot completions,
    // so its presence/absence cleanly distinguishes the tag-path branch from the fallback.
    private sealed class FakeCatalog : IScriptTagCatalog
    {
        public Task<IReadOnlyList<string>> GetPathsAsync(string? f, CancellationToken ct)
            => Task.FromResult<IReadOnlyList<string>>(new[] { "Line1.Speed" });
        public Task<ScriptTagInfo?> GetTagInfoAsync(string path, CancellationToken ct)
            => Task.FromResult<ScriptTagInfo?>(new ScriptTagInfo(path, "Virtual tag", "Double", null));
        public Task<IReadOnlyList<string>> GetEquipmentRelativeLeavesAsync(string? f, CancellationToken ct)
            => Task.FromResult<IReadOnlyList<string>>(System.Array.Empty<string>());
    }

    private static readonly ScriptAnalysisService Svc = new(new FakeCatalog());

    // Caret column lands INSIDE the string literal (just after the opening quote). If a test does not
    // hit the tag-path branch, nudge the column to sit on a literal char and re-run — the gate keys off
    // the token under the caret. Columns are 1-based.

    [Fact] public async Task Completion_on_ctx_GetTag_literal_offers_catalog_paths()
    {
        // return ctx.GetTag("|   — caret just after the opening quote
        var res = await Svc.CompleteAsync(new CompletionsRequest("""return ctx.GetTag("""" + "\"", 1, 19));
        res.Items.ShouldContain(i => i.InsertText == "Line1.Speed");
    }

    [Fact] public async Task Completion_on_non_ctx_receiver_does_NOT_offer_catalog_paths()
    {
        // foo.GetTag("|  — receiver is not ctx, so the tag-path branch must NOT fire.
        var res = await Svc.CompleteAsync(new CompletionsRequest("""return foo.GetTag("""" + "\"", 1, 19));
        res.Items.ShouldNotContain(i => i.InsertText == "Line1.Speed");
    }

    [Fact] public async Task Hover_on_ctx_SetVirtualTag_literal_warns_write_is_dropped()
    {
        // hover the path literal inside ctx.SetVirtualTag("V")
        var md = (await Svc.Hover(new HoverRequest("""return ctx.SetVirtualTag("V", 1);""", 1, 27))).Markdown;
        md.ShouldNotBeNull();
        md!.ShouldContain("single-tag mode");
    }

    [Fact] public async Task Hover_on_ctx_GetTag_literal_has_no_dropped_write_note()
    {
        var md = (await Svc.Hover(new HoverRequest("""return ctx.GetTag("V").Value;""", 1, 20))).Markdown;
        md.ShouldNotBeNull();
        md!.ShouldNotContain("single-tag mode");
    }

    [Fact] public async Task Hover_on_non_ctx_receiver_literal_is_not_treated_as_a_tag_path()
    {
        // bar.GetTag("V") — receiver not ctx; must not produce the "Tag path" hover.
        var md = (await Svc.Hover(new HoverRequest("""return bar.GetTag("V");""", 1, 20))).Markdown;
        (md is null || !md.Contains("Tag path")).ShouldBeTrue();
    }
}
```

**Step 2: Run the tests; verify they FAIL**

Run: `dotnet test tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests --filter "FullyQualifiedName~CtxCompletionGuardTests"` (use `dangerouslyDisableSandbox: true`).
Expected: the non-`ctx` tests FAIL (today the gate fires on any receiver) and the SetVirtualTag-note test FAILS (no note yet). The two positive `ctx.` tests may already pass. If a caret-column does not hit the literal branch, adjust the column and re-run until the positive cases hit the tag-path branch, THEN confirm the negatives still fail for the right reason.

**Step 3: Implement Component 1 (receiver guard) + Component 2 (method-discriminated note)**

In `TryGetTagPathLiteral`, change the signature and body:
```csharp
private static bool TryGetTagPathLiteral(SyntaxToken token, out string prefix, out bool isSetVirtualTag)
{
    prefix = "";
    isSetVirtualTag = false;
    var literal = token.Parent as LiteralExpressionSyntax
        ?? token.GetPreviousToken().Parent as LiteralExpressionSyntax;
    if (literal is null || !literal.IsKind(SyntaxKind.StringLiteralExpression)) return false;
    if (literal.Parent is not ArgumentSyntax arg) return false;
    if (arg.Parent is not ArgumentListSyntax argList) return false;
    if (argList.Parent is not InvocationExpressionSyntax inv) return false;
    if (inv.Expression is not MemberAccessExpressionSyntax ma) return false;
    // Receiver guard: only ctx.GetTag(...) / ctx.SetVirtualTag(...) are real tag-path calls. Mirrors the
    // runtime harvest (EquipmentScriptPaths.GetTagRefRegex is syntactically `ctx`-anchored), so the editor
    // offers tag completions/hover for exactly what Phase7Composer harvests — not an unrelated x.GetTag(...).
    if (ma.Expression is not IdentifierNameSyntax { Identifier.ValueText: "ctx" }) return false;
    var method = ma.Name.Identifier.ValueText;
    if (method is not ("GetTag" or "SetVirtualTag")) return false;
    // only the FIRST argument is the path
    if (argList.Arguments.Count > 0 && argList.Arguments[0] != arg) return false;
    prefix = literal.Token.ValueText ?? "";
    isSetVirtualTag = method == "SetVirtualTag";
    return true;
}
```

Update `CompleteAsync` (the tag-path branch condition) to discard the new param:
```csharp
if (_catalog != null && TryGetTagPathLiteral(token, out var pathPrefix, out _))
```

Update `Hover`'s condition + `tagMd` build:
```csharp
if (_catalog is not null && TryGetTagPathLiteral(token, out var tagPath, out var isSetVirtualTag) && !string.IsNullOrEmpty(tagPath))
{
    ...
    var info = await _catalog.GetTagInfoAsync(tagPath, CancellationToken.None);
    var tagMd = info is null
        ? $"**Tag path** `{Code(tagPath)}`\n\n⚠ Not a known configured tag path."
        : $"**Tag path** `{Code(info.Path)}`\n\n{info.Kind} · Type **{info.DataType}**"
            + (info.DriverInstanceId is null ? "" : $" · Driver `{Code(info.DriverInstanceId)}`");
    // Truthfulness: ctx.SetVirtualTag(...) is a no-op in the live single-tag evaluator
    // (RoslynVirtualTagEvaluator drops cross-tag writes; the cascade VirtualTagEngine is dormant).
    // Surface that so an author is not misled into relying on it.
    if (isSetVirtualTag)
        tagMd += "\n\n⚠ Cross-tag `SetVirtualTag` writes are currently dropped in single-tag mode " +
                 "(the cascade engine is not wired into the host); this write will not take effect at runtime.";
    return new HoverResponse(tagMd);
}
```
(Leave the `{{equip}}` short-circuit branch above this untouched — `SetVirtualTag("{{equip}}.x")` is a rare combination and out of scope.)

**Step 4: Run the tests; verify they PASS**

Run: `dotnet test tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests --filter "FullyQualifiedName~CtxCompletionGuardTests"`
Expected: all 5 PASS.

**Step 5: Run the full AdminUI suite to confirm no regression**

Run: `dotnet test tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests` (use `dangerouslyDisableSandbox: true`).
Expected: green. Existing tag-path tests (e.g. `HoverSignatureTests`) use `ctx.` receivers, so the guard does not affect them. If any pre-existing test used a non-`ctx` receiver on a tag-path literal, that is a real behavior change — surface it, do not weaken the guard.

**Step 6: Commit**
```bash
git add src/Server/ZB.MOM.WW.OtOpcUa.AdminUI/ScriptAnalysis/ScriptAnalysisService.cs \
        tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests/ScriptAnalysis/CtxCompletionGuardTests.cs
git commit -m "fix(adminui): ctx-receiver guard + truthful SetVirtualTag hover in script-editor completions"
```

---

### Task 2: Docs + full build/test + live `/run` + finish

**Classification:** small
**Estimated implement time:** ~4 min (excluding the live-rig step, which the controller drives)
**Parallelizable with:** none (blocked by Task 1)

**Files:**
- Modify: `docs/ScriptEditor.md` (the completions/hover section — note the `ctx`-receiver scoping and that `SetVirtualTag` cross-tag writes are dropped in single-tag mode, hover surfaces this).

**Step 1: Update docs**

In `docs/ScriptEditor.md`, find the section describing tag-path completions/hover and add a short, accurate note:
- Tag-path completions/hover fire only on `ctx.GetTag(...)` / `ctx.SetVirtualTag(...)` (a non-`ctx` receiver is not treated as a tag call), matching the deploy-time dependency harvest.
- `ctx.SetVirtualTag(...)` cross-tag writes are currently dropped by the live single-tag evaluator (the cascade engine is not wired into the host); the editor's hover surfaces this so it is not relied upon. Do NOT overclaim a fix to the cross-tag write path itself.

**Step 2: Full build**

Run: `dotnet build ZB.MOM.WW.OtOpcUa.slnx` (use `dangerouslyDisableSandbox: true`).
Expected: 0 errors.

**Step 3: AdminUI tests**

Run: `dotnet test tests/Server/ZB.MOM.WW.OtOpcUa.AdminUI.Tests` (use `dangerouslyDisableSandbox: true`).
Expected: green.

**Step 4: Commit docs**
```bash
git add docs/ScriptEditor.md
git commit -m "docs(scripteditor): ctx-receiver scoping + SetVirtualTag single-tag-drop note"
```

**Step 5: Live `/run` verification (controller-driven, docker-dev)**

The docker-dev rig is LOCAL + login-disabled (no sign-in needed). Rebuild the AdminUI from the branch and drive the script editor via the Chrome tools against `http://localhost:9200`:
- Open a virtual-tag's ScriptEdit page (or the inline vtag-modal Monaco).
- Type `ctx.GetTag("` → tag-path completions appear.
- Type a non-`ctx` receiver `foo.GetTag("` → tag-path completions do NOT appear (C# completions only).
- Hover a `ctx.SetVirtualTag("…")` literal → the single-tag-drop note shows.

If the rig cannot exercise a step (e.g. Monaco completion timing), record it honestly as unit-proven + smoke-checked rather than overclaiming.

**Step 6: Finish — merge to master + push**

Use superpowers-extended-cc:finishing-a-development-branch: verify tests green, then merge `feat/script-editor-ctx-completions` to master (ff) and push. Stage by explicit path only; never `git add .`; never stage `stillpending.md` / `pending.md` / `docker-dev/docker-compose.yml` / `sql_login.txt` / `pki/`.

---

## Notes for the executor

- **Two tasks, sequential** (Task 2 blocked by Task 1) — both touch a tightly-coupled surface; no parallelism.
- **Hard rules:** stage by path (never `git add .`); never stage the never-stage files; NO runtime/Commons/proto/EF change; NO bUnit; `dangerouslyDisableSandbox: true` for all build/test/rig commands.
- **Done =** build 0 errors + AdminUI tests green + live `/run` confirms the three behaviors → merged to master + pushed.
