'use server'

import DOMPurify from 'isomorphic-dompurify'
import { auth } from '@/auth'
import { prisma } from '@/lib/prisma'
import { getChatProvider } from '@/lib/ai/factory'
import { getSystemConfig } from '@/lib/config'
import { getAISettings } from '@/app/actions/ai-settings'
import { revalidatePath } from 'next/cache'

function extractSvgSnippet(raw: string): string | null {
  const trimmed = raw.trim()
  const fenced = trimmed.match(/```(?:svg)?\s*([\s\S]*?)```/i)
  const candidate = (fenced ? fenced[1] : trimmed).trim()
  const start = candidate.indexOf('<svg')
  const end = candidate.lastIndexOf('</svg>')
  if (start === -1 || end === -1 || end <= start) return null
  return candidate.slice(start, end + 6)
}

function sanitizeSvgMarkup(svg: string): string {
  return DOMPurify.sanitize(svg, {
    USE_PROFILES: { svg: true, svgFilters: true },
    ADD_TAGS: ['use'],
    ADD_ATTR: ['viewBox', 'xmlns', 'preserveAspectRatio'],
  })
}

/**
 * Génère une miniature SVG abstraite pour le flux éditorial (via modèle chat configuré).
 * Respecte les préférences utilisateur (assistant IA activé) et nettoie le SVG.
 */
export async function generateNoteIllustrationSvg(noteId: string): Promise<{ ok: true } | { ok: false; error: string }> {
  const session = await auth()
  if (!session?.user?.id) return { ok: false, error: 'Non autorisé' }

  try {
    const settings = await getAISettings(session.user.id)
    if (settings.paragraphRefactor === false) {
      return { ok: false, error: 'Assistant IA désactivé dans vos paramètres.' }
    }

    const note = await prisma.note.findFirst({
      where: { id: noteId, userId: session.user.id },
      select: { id: true, title: true, content: true },
    })
    if (!note) return { ok: false, error: 'Note introuvable' }

    const plainTitle = (note.title || '').slice(0, 200)
    const plainBody = note.content
      .replace(/<[^>]+>/g, ' ')
      .replace(/\s+/g, ' ')
      .trim()
      .slice(0, 1200)

    if (!plainBody && !plainTitle) {
      return { ok: false, error: 'Ajoutez du contenu avant de générer une illustration.' }
    }

    const config = await getSystemConfig()
    const provider = getChatProvider(config)

    const prompt = `Create a small SVG thumbnail that VISUALLY REPRESENTS this note's topic.

OUTPUT: Only raw SVG markup. No markdown, no code fences, no comments. Start with <svg and end with </svg>.

SPECIFICATIONS:
- viewBox="0 0 224 168", NO fixed width/height attributes
- Maximum 1000 bytes
- Background: soft warm beige (#F5F0E8) or transparent
- Color palette (pick 2-3): warm charcoal (#2C2C2C), slate gray (#6B7280), soft sage (#A8B5A0), muted ochre (#C4A882), dusty rose (#C9A9A6), teal (#5F9EA0), burgundy (#8B4513)
- NO text, NO scripts, NO foreignObject, NO external links

CRITICAL: The illustration MUST be recognizably related to the topic.
Think of it like an ICON or PICTOGRAM for the title. Not abstract random shapes.

TOPIC: "${plainTitle || 'untitled'}"

How to illustrate this topic (pick the BEST match):
- If the topic is about CODE/DEV: Show angle brackets <>, curly braces {}, a terminal window shape, or circuit-like lines
- If the topic is about MUSIC: Show sound waves, musical notes shapes, or speaker icon
- If the topic is about FOOD/COOKING: Show a pot shape, utensils, or plate
- If the topic is about TRAVEL: Show a path/road, mountain peaks, or compass
- If the topic is about SCIENCE: Show atom orbits, flask/beaker, or molecule bonds
- If the topic is about BUSINESS/FINANCE: Show ascending chart lines, coins, or briefcase
- If the topic is about HEALTH: Show heart shape, pulse line, or leaf
- If the topic is about EDUCATION: Show book shape, graduation cap, or pencil
- If the topic is about NATURE: Show tree, mountain, water wave, or sun
- If the topic is about DESIGN/ART: Show palette, brush stroke, or frame
- If the topic is about PEOPLE/TEAM: Show overlapping circles, handshake, or connected nodes
- If the topic is about ARCHITECTURE: Show building outline, blueprint grid, or columns
- Otherwise: Extract the KEY CONCEPT from the title and draw its SIMPLEST iconic representation

TECHNICAL RULES:
- Use simple shapes: <circle>, <rect>, <line>, <path>, <ellipse>, <polygon>, <g>
- Keep it FLAT and MINIMAL — 2-4 elements max
- Use opacity for depth (0.3-0.8)
- The icon should be immediately recognizable even at small size

Additional context from the note:
${plainBody.slice(0, 200)}`

    const raw = await provider.generateText(prompt)
    const extracted = extractSvgSnippet(raw)
    if (!extracted) {
      return { ok: false, error: 'Le modèle n’a pas renvoyé un SVG valide. Réessayez.' }
    }

    const safe = sanitizeSvgMarkup(extracted)
    if (!safe.includes('<svg')) {
      return { ok: false, error: 'SVG rejeté après sécurisation.' }
    }

    await prisma.note.update({
      where: { id: noteId, userId: session.user.id },
      data: {
        illustrationSvg: safe,
        lastAiAnalysis: new Date(),
      },
    })

    revalidatePath('/home')
    return { ok: true }
  } catch (e) {
    console.error('[note-illustration]', e)
    const msg = e instanceof Error ? e.message : 'Erreur inconnue'
    return { ok: false, error: msg.includes('required') ? 'Configurez un fournisseur IA (admin ou paramètres système).' : msg }
  }
}