import { defineConfig } from 'vite';
import path from 'path';
import fs from 'fs';
import tailwindcss from '@tailwindcss/vite';
import react from '@vitejs/plugin-react';

// ── Monorepo dev aliases (auto-detected) ────────────────────────────────────
// When this vite.config lives inside the xertica-ui monorepo (i.e. the
// `components/` directory exists one level up), we alias every `xertica-ui/*`
// subpath directly to the TypeScript source so Vite HMR picks up changes
// without a full `npm run build` in the library root.
//
// When this file is copied to a project scaffolded by the CLI, `../components`
// does NOT exist and the aliases are simply skipped — the project resolves
// `xertica-ui` from node_modules as normal.
// ────────────────────────────────────────────────────────────────────────────
const LIB_ROOT = path.resolve(__dirname, '..');
const isMonorepo = fs.existsSync(path.join(LIB_ROOT, 'components', 'index.ts'));

const libAliases = isMonorepo
  ? [
      { find: 'xertica-ui/ui', replacement: path.join(LIB_ROOT, 'components/ui/index.ts') },
      { find: 'xertica-ui/blocks', replacement: path.join(LIB_ROOT, 'components/blocks/index.ts') },
      {
        find: 'xertica-ui/assistant',
        replacement: path.join(LIB_ROOT, 'components/assistant/index.ts'),
      },
      { find: 'xertica-ui/layout', replacement: path.join(LIB_ROOT, 'components/layout/index.ts') },
      { find: 'xertica-ui/brand', replacement: path.join(LIB_ROOT, 'components/brand/index.ts') },
      { find: 'xertica-ui/media', replacement: path.join(LIB_ROOT, 'components/media/index.ts') },
      { find: 'xertica-ui/hooks', replacement: path.join(LIB_ROOT, 'components/hooks/index.ts') },
      { find: 'xertica-ui/pages', replacement: path.join(LIB_ROOT, 'components/pages/index.ts') },
      { find: 'xertica-ui/style.css', replacement: path.join(LIB_ROOT, 'styles/globals.css') },
      // Bare `xertica-ui` must come AFTER subpaths (most-specific first).
      { find: 'xertica-ui', replacement: path.join(LIB_ROOT, 'components/index.ts') },
    ]
  : [];

// ── Monorepo-only Tailwind @source shim ─────────────────────────────────────
// Tailwind's content scanner walks down from the project root and never
// reaches `LIB_ROOT/components` — a sibling of `templates/`, not a
// descendant — even though the aliases above resolve `xertica-ui/*` imports
// there. Without this, any Tailwind class used only inside library source
// (and not duplicated elsewhere under templates/src) never gets generated in
// this dev server. Only active in monorepo mode; scaffolded projects never
// satisfy `isMonorepo`, so this plugin becomes a no-op and they keep relying
// solely on the `@source` line already inside src/styles/index.css (which
// targets node_modules/xertica-ui/components).
const monorepoTailwindSourcePlugin = isMonorepo
  ? {
      name: 'xertica-monorepo-tailwind-source',
      enforce: 'pre' as const,
      transform(code: string, id: string) {
        if (id.replace(/\\/g, '/').endsWith('src/styles/index.css')) {
          const componentsPath = path.join(LIB_ROOT, 'components').replace(/\\/g, '/');
          return `${code}\n@source '${componentsPath}';\n`;
        }
      },
    }
  : null;

export default defineConfig({
  plugins: [
    // The React and Tailwind plugins are both required for Make, even if
    // Tailwind is not being actively used — do not remove them.
    react(),
    monorepoTailwindSourcePlugin,
    tailwindcss(),
  ],
  resolve: {
    alias: [
      ...libAliases,
      // Alias @ to the src directory
      { find: '@', replacement: path.resolve(__dirname, './src') },
    ],
  },

  // File types to support raw imports. Never add .css, .tsx, or .ts files to this.
  assetsInclude: ['**/*.svg', '**/*.csv'],

  // Dev-only: forwards to server/fdm-proxy.mjs (run separately via `npm run
  // server`) so the frontend can call same-origin `/api/...` instead of
  // talking to FDM directly (FDM sends no CORS headers).
  server: {
    proxy: {
      '/api': 'http://localhost:8787',
    },
  },
});