import fs from 'node:fs/promises';
import path from 'node:path';

import { optimizeLodashImports } from '@optimize-lodash/rollup-plugin';
import react from '@vitejs/plugin-react';
import { PluginOption } from 'vite';
import svgr from 'vite-plugin-svgr';
import { visualizer } from 'rollup-plugin-visualizer';
import RailsPlugin from 'vite-plugin-rails';
import { VitePWA } from 'vite-plugin-pwa';
import tsconfigPaths from 'vite-tsconfig-paths';
import yaml from 'js-yaml';
import legacy from '@vitejs/plugin-legacy';

import { defineConfig, UserConfigFnPromise, UserConfig } from 'vite';
import postcssPresetEnv from 'postcss-preset-env';

import { MastodonServiceWorkerLocales } from './config/vite/plugin-sw-locales';
import { MastodonEmojiCompressed } from './config/vite/plugin-emoji-compressed';

const jsRoot = path.resolve(__dirname, 'app/javascript');
const themesFile = path.resolve(__dirname, 'config/themes.yml');

export const config: UserConfigFnPromise = async ({ mode, command }) => {
  const entrypoints: Record<string, string> = {}; // All JS entrypoints are taken care of by Vite Ruby

  // Get all files mentioned in the themes.yml file.
  const themesString = await fs.readFile(themesFile, 'utf8');
  const themes = yaml.load(themesString, {
    filename: 'themes.yml',
    schema: yaml.FAILSAFE_SCHEMA,
  });

  if (!themes || typeof themes !== 'object') {
    throw new Error('Invalid themes.yml file');
  }

  for (const themePath of Object.values(themes)) {
    if (
      typeof themePath !== 'string' ||
      themePath.split('.').length !== 2 || // Ensure it has exactly one period
      !themePath.endsWith('css')
    ) {
      console.warn(`Invalid theme path "${themePath}" in themes.yml, skipping`);
      continue;
    }
    entrypoints[path.basename(themePath)] = path.resolve(jsRoot, themePath);
  }

  return {
    root: jsRoot,
    css: {
      postcss: {
        plugins: [
          postcssPresetEnv({
            features: {
              'logical-properties-and-values': false,
            },
          }),
        ],
      },
    },
    server: {
      headers: {
        // This is needed in dev environment because we load the worker from `/dev-sw/dev-sw.js`,
        // but it needs to be scoped to the whole domain
        'Service-Worker-Allowed': '/',
      },
    },
    build: {
      commonjsOptions: { transformMixedEsModules: true },
      chunkSizeWarningLimit: 1 * 1024 * 1024, // 1MB
      sourcemap: true,
      rollupOptions: {
        input: entrypoints,
        output: {
          chunkFileNames({ facadeModuleId, name }) {
            if (!facadeModuleId) {
              return '[name]-[hash].js';
            }
            if (/mastodon\/locales\/[a-zA-Z\-]+\.json/.exec(facadeModuleId)) {
              // put all locale files in `intl/`
              return 'intl/[name]-[hash].js';
            } else if (/node_modules\/@formatjs\//.exec(facadeModuleId)) {
              // use a custom name for formatjs polyfill files
              const newName = /node_modules\/@formatjs\/([^/]+)\//.exec(
                facadeModuleId,
              );

              if (newName?.[1]) {
                return `intl/[name]-${newName[1]}-[hash].js`;
              }
            } else if (name === 'index') {
              // Use a custom name for chunks, to avoid having too many of them called "index"
              const parts = facadeModuleId.split('/');

              const parent = parts.at(-2);

              if (parent) {
                return `${parent}-[name]-[hash].js`;
              }
            }
            return '[name]-[hash].js';
          },
        },
      },
    },
    plugins: [
      tsconfigPaths(),
      RailsPlugin({
        compress: mode === 'production' && command === 'build',
        sri: {
          manifestPaths: ['.vite/manifest.json', '.vite/manifest-assets.json'],
        },
      }),
      react({
        babel: {
          plugins: ['formatjs', 'transform-react-remove-prop-types'],
        },
      }),
      MastodonServiceWorkerLocales(),
      MastodonEmojiCompressed(),
      legacy({
        renderLegacyChunks: false,
        modernPolyfills: true,
      }),
      VitePWA({
        srcDir: 'mastodon/service_worker',
        // We need to use injectManifest because we use our own service worker
        strategies: 'injectManifest',
        manifest: false,
        injectRegister: false,
        injectManifest: {
          // Do not inject a manifest, we don't use precache
          injectionPoint: undefined,
          buildPlugins: {
            vite: [
              // Provide a virtual import with only the locales used in the ServiceWorker
              MastodonServiceWorkerLocales(),
              MastodonEmojiCompressed(),
            ],
          },
        },
        // Force the output location, because we have a symlink in `public/sw.js`
        outDir: path.resolve(__dirname, 'public/packs'),
        devOptions: {
          enabled: true,
          type: 'module',
        },
      }),
      svgr(),
      // Old library types need to be converted
      optimizeLodashImports() as PluginOption,
      !!process.env.ANALYZE_BUNDLE_SIZE && (visualizer() as PluginOption),
    ],
  } satisfies UserConfig;
};

export default defineConfig(config);