/**
 * Assets IO — lecture des métadonnées PNG, copie des fichiers ingrédients
 * et branding vers `apps/web/public`, sélection d'une cover recette.
 *
 * Aucun parsing : ces fonctions touchent le système de fichiers. Le parsing
 * bentext / sprite vit dans `parse-bentext.mjs` et `sprites.mjs`.
 */

import { promises as fs } from "node:fs";
import path from "node:path";
import { fileURLToPath } from "node:url";

const repoRoot = path.resolve(path.dirname(fileURLToPath(import.meta.url)), "..", "..");

/** Fichiers d’ingrédients copiés tels quels vers `apps/web/public`. */
const INGREDIENT_ASSET_FILES = ["ingredients.png", "ingredient-sprites.csv", "ingredient-unknown.png"];

/** Fichiers de branding copiés tels quels vers `apps/web/public/branding`. */
export const BRANDING_FILES = ["onigiri-logo.png", "og.jpg"];

export const PATHS = {
  repoRoot,
  recipesDir: path.join(repoRoot, "ressources/bentext"),
  outDir: path.join(repoRoot, "ressources/generated"),
  webPublicDir: path.join(repoRoot, "apps/web/public/recipes"),
  webCoverDir: path.join(repoRoot, "apps/web/public/recipe-covers"),
  webBrandingDir: path.join(repoRoot, "apps/web/public/branding"),
  webPublicRoot: path.join(repoRoot, "apps/web/public"),
  publicAssetsDir: path.join(repoRoot, "ressources/public"),
  placeholderCoversDir: path.join(repoRoot, "ressources/recipe-placeholder-covers"),
  /** Grille des tuiles : coordonnées et alias listés dans ce fichier (plus d’API). */
  ingredientSpritesBentextPath: path.join(repoRoot, "ressources/public/ingredient-sprites.bentext"),
  ingredientsPngPath: path.join(repoRoot, "ressources/public/ingredients.png")
};

const COVER_EXTENSIONS = [".jpg", ".jpeg", ".png", ".webp"];

const readPngDimensions = async (filePath) => {
  try {
    const buf = await fs.readFile(filePath);
    if (buf.length < 24 || buf[0] !== 0x89) return null;
    const width = buf.readUInt32BE(16);
    const height = buf.readUInt32BE(20);
    return { width, height };
  } catch {
    return null;
  }
};

const copyIngredientAssetsToWeb = async () => {
  await fs.mkdir(PATHS.webPublicRoot, { recursive: true });
  for (const name of INGREDIENT_ASSET_FILES) {
    const src = path.join(PATHS.publicAssetsDir, name);
    const dest = path.join(PATHS.webPublicRoot, name);
    try {
      await fs.copyFile(src, dest);
    } catch (error) {
      if (error && error.code === "ENOENT") continue;
      throw error;
    }
  }
};

const copyBrandingAssets = async () => {
  await fs.mkdir(PATHS.webBrandingDir, { recursive: true });
  for (const name of BRANDING_FILES) {
    const src = path.join(PATHS.publicAssetsDir, name);
    const dest = path.join(PATHS.webBrandingDir, name);
    try {
      await fs.copyFile(src, dest);
    } catch (error) {
      if (error && error.code === "ENOENT") {
        console.warn(`Branding asset missing, skip: ${name}`);
        continue;
      }
      throw error;
    }
  }
};

/**
 * Sélectionne une cover pour `slug` :
 *   1. Image HD dans `ressources/recipe-placeholder-covers/<slug>.png`.
 *   2. Sinon, image dans `ressources/public/<slug>.<ext>`.
 * Copie le fichier dans `apps/web/public/recipe-covers/` et retourne l’URL publique.
 */
const pickCoverImage = async (slug) => {
  await fs.mkdir(PATHS.webCoverDir, { recursive: true });
  /* Priorité aux visuels HD du dépôt ; sinon ressources/public (override legacy). */
  const placeholderPng = path.join(PATHS.placeholderCoversDir, `${slug}.png`);
  try {
    await fs.access(placeholderPng);
    const publicName = `${slug}.png`;
    const target = path.join(PATHS.webCoverDir, publicName);
    await fs.copyFile(placeholderPng, target);
    return `/recipe-covers/${publicName}`;
  } catch {
    // continue
  }
  for (const extension of COVER_EXTENSIONS) {
    const candidate = path.join(PATHS.publicAssetsDir, `${slug}${extension}`);
    try {
      await fs.access(candidate);
      const publicName = `${slug}${extension}`;
      const target = path.join(PATHS.webCoverDir, publicName);
      await fs.copyFile(candidate, target);
      return `/recipe-covers/${publicName}`;
    } catch {
      // continue
    }
  }
  return null;
};

export { readPngDimensions, copyIngredientAssetsToWeb, copyBrandingAssets, pickCoverImage };