# Style Preset UI Only Implementation Plan

> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.

**Goal:** Make page style presets affect generated UI tokens only, without changing generated page canvas/layout.

**Architecture:** Keep automatic layout selection inside `PageCompositionService.chooseLayout()`. Resolve the selected `PageStylePreset` only to write `stylePreset`, `styleTokens`, and composition metadata into layout JSON. Remove the canvas override path so presets cannot change table/card/split/dense layout structure.

**Tech Stack:** Java, JUnit 4, Jackson, Spring service classes in `ruoyi-generator`.

---

## File Structure

- Modify: `ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageCompositionServiceStylePresetTest.java`
  - Owns regression tests for `PageCompositionService` style preset behavior.
- Modify: `ruoyi-generator/src/main/java/com/ruoyi/generator/service/front/PageCompositionService.java`
  - Owns deterministic page canvas selection and layout JSON composition.
- Modify: `ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageStylePresetRegistryTest.java`
  - Owns registry contract tests for style tokens, density, and fallback.
- Modify: `ruoyi-generator/src/main/java/com/ruoyi/generator/service/front/PageStylePresetRegistry.java`
  - Owns available visual preset definitions.

### Task 1: Lock Style Presets Out Of Canvas Selection

**Files:**
- Modify: `ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageCompositionServiceStylePresetTest.java`
- Modify: `ruoyi-generator/src/main/java/com/ruoyi/generator/service/front/PageCompositionService.java`

- [ ] **Step 1: Write the failing frontend regression test**

Replace `cardPortalPresetPrefersCardCanvasForFrontendLists` with:

```java
@Test
public void cardPortalPresetKeepsAutomaticallySelectedFrontendCanvas()
{
    FrontProjectPageDesign design = design("frontend", "list");

    service.compose(design, table(), Arrays.asList(
            column("title", "title", "1", "1", "1"),
            column("status", "status", "1", "1", "1")), null, null, true, "card_portal");

    Map<String, Object> layout = readLayout(design);
    assertEquals("frontend-list-v1", layout.get("canvas"));
    assertEquals("card_portal", layout.get("stylePreset"));
    assertTrue(((Map<?, ?>) layout.get("styleTokens")).containsKey("primary"));
    Map<?, ?> composition = (Map<?, ?>) layout.get("composition");
    assertEquals("card_portal", composition.get("stylePreset"));
    assertTrue(String.valueOf(composition.get("reasons")).contains("card_portal"));
}
```

- [ ] **Step 2: Write the failing admin regression test**

Replace `dataDensePresetPrefersDenseCanvasForAdminLists` with:

```java
@Test
public void dataDensePresetKeepsAutomaticallySelectedAdminCanvas()
{
    FrontProjectPageDesign design = design("admin", "list");

    service.compose(design, table(), Arrays.asList(
            column("code", "code", "1", "1", "1"),
            column("name", "name", "1", "1", "1")), null, null, true, "data_dense");

    Map<String, Object> layout = readLayout(design);
    assertEquals("admin-list-v1", layout.get("canvas"));
    assertEquals("data_dense", layout.get("stylePreset"));
    assertTrue(((Map<?, ?>) layout.get("styleTokens")).containsKey("primary"));
}
```

- [ ] **Step 3: Run tests to verify they fail**

Run:

```bash
mvn -pl ruoyi-generator -Dtest=PageCompositionServiceStylePresetTest test
```

Expected: both tests fail because the current implementation changes `canvas` to `frontend-list-card-v1` and `admin-list-dense-v1`.

- [ ] **Step 4: Implement minimal service change**

In `PageCompositionService.compose(...)`, replace:

```java
stylePreset = stylePresetRegistry.resolve(stylePresetCode);
applyStylePreset(decision, pageType, scope, stylePreset);
```

with:

```java
stylePreset = stylePresetRegistry.resolve(stylePresetCode);
decision.addReason("style preset " + stylePreset.getCode() + " applied visual tokens");
```

Then remove the unused `applyStylePreset(...)` method.

- [ ] **Step 5: Run tests to verify they pass**

Run:

```bash
mvn -pl ruoyi-generator -Dtest=PageCompositionServiceStylePresetTest test
```

Expected: `Tests run: 2, Failures: 0, Errors: 0`.

### Task 2: Remove Canvas Mapping From The Registry Contract

**Files:**
- Modify: `ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageStylePresetRegistryTest.java`
- Modify: `ruoyi-generator/src/main/java/com/ruoyi/generator/service/front/PageStylePresetRegistry.java`

- [ ] **Step 1: Write the failing registry contract test**

Replace `resolvesKnownPresetWithCanvasAndTokens` with:

```java
@Test
public void resolvesKnownPresetWithTokensOnly()
{
    PageStylePresetRegistry registry = new PageStylePresetRegistry();

    PageStylePresetRegistry.PageStylePreset preset = registry.resolve("card_portal");

    assertEquals("card_portal", preset.getCode());
    assertEquals("#167d83", preset.token("primary", ""));
    assertEquals("#f6c85b", preset.token("accent", ""));
    assertEquals("comfortable", preset.getDensity());
    assertTrue(registry.options().size() >= 4);
}
```

Replace `unknownPresetFallsBackToBusinessClean` with:

```java
@Test
public void unknownPresetFallsBackToBusinessCleanTokens()
{
    PageStylePresetRegistry registry = new PageStylePresetRegistry();

    PageStylePresetRegistry.PageStylePreset preset = registry.resolve("not_real");

    assertEquals("business_clean", preset.getCode());
    assertEquals("#167d83", preset.token("primary", ""));
    assertEquals("1200px", preset.token("contentWidth", ""));
}
```

- [ ] **Step 2: Run registry test before implementation**

Run:

```bash
mvn -pl ruoyi-generator -Dtest=PageStylePresetRegistryTest test
```

Expected: test compilation fails after removing frontend/admin canvas assertions from tests only if production still exposes unused API is not a compile failure; if tests pass immediately, continue with the cleanup as refactor under the Task 1 green state.

- [ ] **Step 3: Remove registry canvas API and definitions**

In `PageStylePresetRegistry`, remove:

```java
private final Map<String, String> frontendCanvases = new LinkedHashMap<String, String>();
private final Map<String, String> adminCanvases = new LinkedHashMap<String, String>();
```

Remove all `.frontend(...)` and `.admin(...)` calls from preset definitions. Remove the private builder methods `frontend(...)` and `admin(...)`. Remove public methods `frontendCanvas(...)` and `adminCanvas(...)`.

- [ ] **Step 4: Run registry tests**

Run:

```bash
mvn -pl ruoyi-generator -Dtest=PageStylePresetRegistryTest test
```

Expected: `Tests run: 2, Failures: 0, Errors: 0`.

### Task 3: Final Verification

**Files:**
- Test: `ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageCompositionServiceStylePresetTest.java`
- Test: `ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageStylePresetRegistryTest.java`

- [ ] **Step 1: Run focused tests together**

Run:

```bash
mvn -pl ruoyi-generator -Dtest=PageCompositionServiceStylePresetTest,PageStylePresetRegistryTest test
```

Expected: both test classes pass.

- [ ] **Step 2: Inspect diff for scope**

Run:

```bash
git diff -- ruoyi-generator/src/main/java/com/ruoyi/generator/service/front/PageCompositionService.java ruoyi-generator/src/main/java/com/ruoyi/generator/service/front/PageStylePresetRegistry.java ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageCompositionServiceStylePresetTest.java ruoyi-generator/src/test/java/com/ruoyi/generator/service/front/PageStylePresetRegistryTest.java
```

Expected: diff only changes style preset canvas coupling and corresponding tests.