---
phase: 07-seo-blog
plan: 02
type: execute
wave: 2
depends_on: [07-01]
files_modified:
  - app/utils/resolve-og-image.ts
  - public/og-blog-default.jpg
  - app/pages/blog/[slug].vue
autonomous: true
requirements: [SEO-10, SEO-11, SEO-13, SEO-15]
must_haves:
  truths:
    - "curl /fr/blog/{slug} retourne og:title, og:description, og:image UNIQUES (par article)"
    - "og:image est absolute (https://...) et = frontmatter image || /og-blog-default.jpg (jamais og-image.png générique)"
    - "Le HTML contient un JSON-LD `@type: Article` avec headline, description, datePublished, dateModified, author (@id=#killian), publisher (@id=#killian), inLanguage, mainEntityOfPage"
    - "Le HTML contient un JSON-LD `@type: BreadcrumbList` Accueil → Blog → Titre"
    - "article:published_time et article:modified_time présents (ISO 8601)"
    - "og:locale:alternate émis uniquement si l'article existe dans les 2 langues"
  artifacts:
    - path: "app/utils/resolve-og-image.ts"
      provides: "resolveOgImage(article) → URL absolue"
      contains: "export function resolveOgImage"
    - path: "public/og-blog-default.jpg"
      provides: "fallback branded 1200x630"
    - path: "app/pages/blog/[slug].vue"
      provides: "useSeoMeta enrichi + useSchemaOrg([defineArticle, defineBreadcrumb])"
      contains: "defineArticle"
  key_links:
    - from: "app/pages/blog/[slug].vue"
      to: "app/utils/resolve-og-image.ts"
      via: "import resolveOgImage"
      pattern: "resolveOgImage"
    - from: "app/pages/blog/[slug].vue (defineArticle.author)"
      to: "app/app.vue (definePerson global)"
      via: "@id reference"
      pattern: "'@id': KILLIAN_PERSON_ID"
---

<objective>
Enrichir la page article `/blog/[slug]` avec (a) `useSeoMeta` étendu (D-15), (b) `useSchemaOrg([defineArticle, defineBreadcrumb])` (D-02, SEO-11, SEO-15), et (c) helper partagé `resolveOgImage` + asset fallback `/og-blog-default.jpg` (D-05, D-06, SEO-13).

Purpose: SEO-10/11/13/15 — satisfaire les 4 success criteria curl de la phase sur `/blog/[slug]`.
Output: 1 util créé, 1 asset déposé, 1 page enrichie.
</objective>

<execution_context>
@$HOME/.claude/get-shit-done/workflows/execute-plan.md
@$HOME/.claude/get-shit-done/templates/summary.md
</execution_context>

<context>
@.planning/ROADMAP.md
@.planning/STATE.md
@.planning/phases/07-seo-blog/07-CONTEXT.md
@.planning/phases/07-seo-blog/07-RESEARCH.md
@.planning/phases/07-seo-blog/07-PATTERNS.md
@.planning/phases/07-seo-blog/07-01-SUMMARY.md
@app/pages/blog/[slug].vue
@app/utils/countWords.ts
@app/utils/seo-person.ts

<interfaces>
Depuis `app/utils/seo-person.ts` (créé 07-01) :
- `KILLIAN_PERSON_ID = '#killian'`
- `killianPerson` (pour référence)

Depuis `app/pages/blog/[slug].vue` (existant, à étendre — ne PAS remplacer) :
- `const { t, locale } = useI18n()` (ligne 2)
- `const localePath = useLocalePath()` (ligne 3)
- `const isFr = computed(() => locale.value === 'fr')` (ligne 5)
- `const slug = route.params.slug as string` (ligne 6)
- `const path = computed(() => ...)` (ligne 7)
- `const { data: page } = await useAsyncData(...)` (lignes 10-17) — carry `title, description, date, updated?, image?, tags?`
- `useSeoMeta({ title, description, ogTitle, ogDescription, ogType: 'article' })` (lignes 93-99) — à ÉTENDRE

Auto-imports nuxt-schema-org disponibles : `useSchemaOrg`, `defineArticle`, `defineBreadcrumb`.

`resolveOgImage(article?: { image?: string } | null): string` — retourne URL absolue préfixée par `https://killiandalcin.fr`.
</interfaces>
</context>

<tasks>

<task type="auto">
  <name>Task 1: Créer app/utils/resolve-og-image.ts + déposer public/og-blog-default.jpg</name>
  <files>app/utils/resolve-og-image.ts, public/og-blog-default.jpg</files>
  <read_first>
    - app/utils/countWords.ts (pattern JSDoc + export nommé)
    - .planning/phases/07-seo-blog/07-RESEARCH.md §Pattern 4 (resolveOgImage helper)
    - .planning/phases/07-seo-blog/07-PATTERNS.md §resolve-og-image.ts
  </read_first>
  <action>
    1. Créer `app/utils/resolve-og-image.ts` avec contenu exact :
       ```ts
       /**
        * Resolves an article's og:image to an absolute URL.
        * Strategy (D-05): frontmatter `image` if present, else branded fallback `/og-blog-default.jpg`.
        * Consumed by: app/pages/blog/[slug].vue (useSeoMeta.ogImage + defineArticle.image)
        *              app/pages/blog/index.vue (useSeoMeta.ogImage fallback only).
        */
       const SITE_URL = 'https://killiandalcin.fr'
       const FALLBACK = '/og-blog-default.jpg'

       export function resolveOgImage(article?: { image?: string } | null): string {
         const raw = article?.image?.trim() || FALLBACK
         if (raw.startsWith('http://') || raw.startsWith('https://')) return raw
         return `${SITE_URL}${raw.startsWith('/') ? raw : `/${raw}`}`
       }
       ```
    2. Déposer un asset `public/og-blog-default.jpg` (1200×630). Placeholder acceptable (RESEARCH Open Question #2) : générer un JPG simple via ImageMagick (si disponible) ou utiliser un existant cropé. Commande minimale si `magick` disponible :
       ```sh
       magick -size 1200x630 gradient:'#0f172a'-'#1e293b' -gravity center -fill white -pointsize 64 -annotate 0 "Blog · killiandalcin.fr" public/og-blog-default.jpg
       ```
       Si `magick` absent, copier `public/og-image.png` en `public/og-blog-default.jpg` via `cp public/og-image.png public/og-blog-default.jpg` COMME DERNIER RECOURS et noter dans le SUMMARY qu'un design définitif reste à produire (checkpoint design report en backlog). L'important est que le fichier existe et soit servable.
  </action>
  <verify>
    <automated>test -f app/utils/resolve-og-image.ts && grep -q "export function resolveOgImage" app/utils/resolve-og-image.ts && test -f public/og-blog-default.jpg && pnpm typecheck</automated>
  </verify>
  <done>Helper exporté type-check OK, asset JPG servable à `/og-blog-default.jpg`.</done>
</task>

<task type="auto">
  <name>Task 2: Enrichir app/pages/blog/[slug].vue — useSeoMeta D-15 + useSchemaOrg defineArticle + defineBreadcrumb</name>
  <files>app/pages/blog/[slug].vue</files>
  <read_first>
    - app/pages/blog/[slug].vue (fichier entier 1-157)
    - .planning/phases/07-seo-blog/07-RESEARCH.md §Pattern 2 (Article Page JSON-LD + Meta), §useSeoMeta Enrichment table
    - .planning/phases/07-seo-blog/07-PATTERNS.md §[slug].vue (modify)
    - .planning/phases/07-seo-blog/07-CONTEXT.md D-13, D-15
  </read_first>
  <action>
    Dans `app/pages/blog/[slug].vue`, zone `<script setup lang="ts">` uniquement (ne PAS toucher au template) :

    1. **Imports** — ajouter au tout début du script (après la ligne 1 `<script setup lang="ts">`) :
       ```ts
       import { KILLIAN_PERSON_ID } from '~/utils/seo-person'
       import { resolveOgImage } from '~/utils/resolve-og-image'
       ```

    2. **Détection pair bilingue** — après le bloc `surround` (après ligne 39), avant `interface SurroundArticle` :
       ```ts
       // Détecter la version dans l'autre langue (pour og:locale:alternate, D-15, Pitfall 7)
       const { data: altExists } = await useAsyncData(
         `blog-alt-${locale.value}-${slug}`,
         () =>
           isFr.value
             ? queryCollection('blog_en').path(`/en/blog/${slug}`).first()
             : queryCollection('blog_fr').path(`/fr/blog/${slug}`).first(),
         { watch: [locale] },
       )
       ```

    3. **Computeds SEO** — après `readingMinutes` computed (ligne 79), AVANT `interface TocLink` :
       ```ts
       const SITE_URL = 'https://killiandalcin.fr'
       const ogImage = computed(() => resolveOgImage(page.value as { image?: string } | null))
       const canonicalUrl = computed(() => `${SITE_URL}${localePath('/blog/' + slug)}`)
       const publishedIso = computed(() => page.value?.date)
       const modifiedIso = computed(() => page.value?.updated ?? page.value?.date)  // D-13
       ```

    4. **Remplacer** le `useSeoMeta({...})` existant (lignes 93-99) par la version enrichie D-15 (arrow-fns pour tout ce qui lit `.value` — Pattern "Reactive arrow-fn values") :
       ```ts
       useSeoMeta({
         title: () => page.value?.title,
         description: () => page.value?.description,
         ogTitle: () => page.value?.title,
         ogDescription: () => page.value?.description,
         ogType: 'article',
         ogImage,
         ogUrl: canonicalUrl,
         ogLocale: () => (isFr.value ? 'fr_FR' : 'en_US'),
         ogLocaleAlternate: () => (altExists.value ? [isFr.value ? 'en_US' : 'fr_FR'] : []),
         twitterCard: 'summary_large_image',
         twitterImage: ogImage,
         articlePublishedTime: publishedIso,
         articleModifiedTime: modifiedIso,
         articleAuthor: () => "Killian' Dal-Cin",
       })
       ```

    5. **Ajouter** après `useSeoMeta(...)` un bloc `useSchemaOrg` :
       ```ts
       useSchemaOrg([
         defineArticle({
           headline: () => page.value?.title,
           description: () => page.value?.description,
           image: ogImage,
           datePublished: publishedIso,
           dateModified: modifiedIso,
           inLanguage: () => (isFr.value ? 'fr-FR' : 'en-US'),
           author: { '@id': KILLIAN_PERSON_ID },
           publisher: { '@id': KILLIAN_PERSON_ID },
           mainEntityOfPage: canonicalUrl,
         }),
         defineBreadcrumb({
           itemListElement: [
             { name: () => t('blog.breadcrumb.home'), item: () => localePath('/') },
             { name: () => t('blog.breadcrumb.blog'), item: () => localePath('/blog') },
             { name: () => page.value?.title ?? '' },
           ],
         }),
       ])
       ```
       Ne PAS toucher aux computeds `breadcrumbItems`, `formattedDate`, `readingMinutes`, `tocLinks`, ni au template.
  </action>
  <verify>
    <automated>grep -q "defineArticle" app/pages/blog/[slug].vue && grep -q "defineBreadcrumb" app/pages/blog/[slug].vue && grep -q "articlePublishedTime" app/pages/blog/[slug].vue && grep -q "resolveOgImage" app/pages/blog/[slug].vue && grep -q "KILLIAN_PERSON_ID" app/pages/blog/[slug].vue && pnpm typecheck && pnpm dev --port 3000 & sleep 12 && SLUG=$(ls content/fr/blog | head -1 | sed 's/\.md$//') && curl -s "http://localhost:3000/fr/blog/$SLUG" | tee /tmp/slug.html | grep -q 'property="og:image".*https://killiandalcin.fr' && grep -q '"@type":"Article"' /tmp/slug.html && grep -q '"@type":"BreadcrumbList"' /tmp/slug.html && grep -q 'property="article:published_time"' /tmp/slug.html && kill %1</automated>
  </verify>
  <done>curl /fr/blog/{slug} HTML contient : og:image absolu, article:published_time, JSON-LD Article (avec author @id=#killian), JSON-LD BreadcrumbList 3 items. typecheck vert.</done>
</task>

</tasks>

<threat_model>
## Trust Boundaries

| Boundary | Description |
|----------|-------------|
| frontmatter → HTML | `image:` du markdown injecté dans meta tags / JSON-LD (auteur = soi-même, confiance élevée) |

## STRIDE Threat Register

| Threat ID | Category | Component | Disposition | Mitigation Plan |
|-----------|----------|-----------|-------------|-----------------|
| T-07-03 | Tampering | `resolveOgImage` (URL depuis frontmatter) | mitigate | Helper construit URL en préfixant SITE_URL ; frontmatter écrit par l'auteur unique (pas de user input externe) |
| T-07-04 | Information Disclosure | JSON-LD article (author) | accept | Identité Killian publique par design |
</threat_model>

<verification>
- Helper vérifiable : `grep "export function resolveOgImage" app/utils/resolve-og-image.ts`
- og:image absolu : `curl /fr/blog/{slug} | grep 'property="og:image"' | grep 'https://'`
- JSON-LD Article : `curl /fr/blog/{slug} | grep '"@type":"Article"'`
- JSON-LD BreadcrumbList : `curl /fr/blog/{slug} | grep '"@type":"BreadcrumbList"'`
- article:published_time : `curl /fr/blog/{slug} | grep 'property="article:published_time"'`
- Pas de client-only : tout doit être dans le HTML initial SSR (pas de diff après hydratation)
</verification>

<success_criteria>
1. SEO-10 : `curl /fr/blog/{slug}` contient og:title, og:description, og:image uniques (dépendent de `page.title`/`description`/`image`)
2. SEO-11 : JSON-LD Article valide avec author, datePublished, dateModified, headline
3. SEO-13 : og:image = frontmatter absolutisé OR `https://killiandalcin.fr/og-blog-default.jpg`, jamais `og-image.png`
4. SEO-15 : JSON-LD BreadcrumbList Accueil → Blog → {title}
</success_criteria>

<output>
Après complétion, créer `.planning/phases/07-seo-blog/07-02-SUMMARY.md`.
</output>
