#!/usr/bin/env -S deno run --allow-all
/**
 * UI Bundler Script
 * Encodes all files from ui/dist/registry-ui/browser/ as base64
 * and generates ts/embedded-ui.generated.ts
 *
 * Usage:
 *   deno task bundle-ui           # One-time bundle
 *   deno task bundle-ui:watch     # Watch mode for development
 */

import { walk } from 'jsr:@std/fs@1/walk';
import { extname, relative } from 'jsr:@std/path@1';
import { encodeBase64 } from 'jsr:@std/encoding@1/base64';

const UI_DIST_PATH = './ui/dist/registry-ui/browser';
const OUTPUT_PATH = './ts/embedded-ui.generated.ts';

const CONTENT_TYPES: Record<string, string> = {
  '.html': 'text/html',
  '.js': 'application/javascript',
  '.css': 'text/css',
  '.json': 'application/json',
  '.png': 'image/png',
  '.jpg': 'image/jpeg',
  '.jpeg': 'image/jpeg',
  '.gif': 'image/gif',
  '.svg': 'image/svg+xml',
  '.ico': 'image/x-icon',
  '.woff': 'font/woff',
  '.woff2': 'font/woff2',
  '.ttf': 'font/ttf',
  '.eot': 'application/vnd.ms-fontobject',
  '.otf': 'font/otf',
  '.map': 'application/json',
  '.txt': 'text/plain',
  '.xml': 'application/xml',
  '.webp': 'image/webp',
  '.webmanifest': 'application/manifest+json',
};

interface IEmbeddedFile {
  path: string;
  base64: string;
  contentType: string;
  size: number;
}

async function bundleUI(): Promise<void> {
  console.log('[bundle-ui] Starting UI bundling...');
  console.log(`[bundle-ui] Source: ${UI_DIST_PATH}`);
  console.log(`[bundle-ui] Output: ${OUTPUT_PATH}`);

  // Check if UI dist exists
  try {
    await Deno.stat(UI_DIST_PATH);
  } catch {
    console.error(`[bundle-ui] ERROR: UI dist not found at ${UI_DIST_PATH}`);
    console.error('[bundle-ui] Run "deno task build" first to build the UI');
    Deno.exit(1);
  }

  const files: IEmbeddedFile[] = [];
  let totalSize = 0;

  // Walk through all files in the dist directory
  for await (const entry of walk(UI_DIST_PATH, { includeFiles: true, includeDirs: false })) {
    const relativePath = '/' + relative(UI_DIST_PATH, entry.path).replace(/\\/g, '/');
    const ext = extname(entry.path).toLowerCase();
    const contentType = CONTENT_TYPES[ext] || 'application/octet-stream';

    // Read file and encode as base64
    const content = await Deno.readFile(entry.path);
    const base64 = encodeBase64(content);

    files.push({
      path: relativePath,
      base64,
      contentType,
      size: content.length,
    });

    totalSize += content.length;
    console.log(`[bundle-ui] Encoded: ${relativePath} (${formatSize(content.length)})`);
  }

  // Sort files for consistent output
  files.sort((a, b) => a.path.localeCompare(b.path));

  // Generate TypeScript module
  const tsContent = generateTypeScript(files, totalSize);

  // Write output file
  await Deno.writeTextFile(OUTPUT_PATH, tsContent);

  console.log(`[bundle-ui] Generated ${OUTPUT_PATH}`);
  console.log(`[bundle-ui] Total files: ${files.length}`);
  console.log(`[bundle-ui] Total size: ${formatSize(totalSize)}`);
  console.log(`[bundle-ui] Bundling complete!`);
}

function generateTypeScript(files: IEmbeddedFile[], totalSize: number): string {
  const fileEntries = files
    .map(
      (f) =>
        `  ['${f.path}', { base64: '${f.base64}', contentType: '${f.contentType}' }]`
    )
    .join(',\n');

  return `// AUTO-GENERATED FILE - DO NOT EDIT
// Generated by scripts/bundle-ui.ts
// Total files: ${files.length}
// Total size: ${formatSize(totalSize)}
// Generated at: ${new Date().toISOString()}

interface IEmbeddedFile {
  base64: string;
  contentType: string;
}

const EMBEDDED_FILES: Map<string, IEmbeddedFile> = new Map([
${fileEntries}
]);

/**
 * Get an embedded file by path
 * @param path - The file path (e.g., '/index.html')
 * @returns The file data and content type, or null if not found
 */
export function getEmbeddedFile(path: string): { data: Uint8Array; contentType: string } | null {
  const file = EMBEDDED_FILES.get(path);
  if (!file) return null;

  // Decode base64 to Uint8Array
  const binaryString = atob(file.base64);
  const bytes = new Uint8Array(binaryString.length);
  for (let i = 0; i < binaryString.length; i++) {
    bytes[i] = binaryString.charCodeAt(i);
  }

  return { data: bytes, contentType: file.contentType };
}

/**
 * Check if an embedded file exists
 * @param path - The file path to check
 */
export function hasEmbeddedFile(path: string): boolean {
  return EMBEDDED_FILES.has(path);
}

/**
 * List all embedded file paths
 */
export function listEmbeddedFiles(): string[] {
  return Array.from(EMBEDDED_FILES.keys());
}

/**
 * Get the total number of embedded files
 */
export function getEmbeddedFileCount(): number {
  return EMBEDDED_FILES.size;
}
`;
}

function formatSize(bytes: number): string {
  if (bytes < 1024) return `${bytes} B`;
  if (bytes < 1024 * 1024) return `${(bytes / 1024).toFixed(1)} KB`;
  return `${(bytes / (1024 * 1024)).toFixed(2)} MB`;
}

async function watchMode(): Promise<void> {
  console.log('[bundle-ui] Starting watch mode...');
  console.log(`[bundle-ui] Watching: ${UI_DIST_PATH}`);
  console.log('[bundle-ui] Press Ctrl+C to stop');
  console.log('');

  // Initial bundle
  await bundleUI();

  // Watch for changes
  const watcher = Deno.watchFs(UI_DIST_PATH);
  let debounceTimer: number | null = null;

  for await (const event of watcher) {
    if (event.kind === 'modify' || event.kind === 'create' || event.kind === 'remove') {
      // Debounce - wait 500ms after last change
      if (debounceTimer) {
        clearTimeout(debounceTimer);
      }
      debounceTimer = setTimeout(async () => {
        console.log('');
        console.log(`[bundle-ui] Change detected: ${event.kind}`);
        try {
          await bundleUI();
        } catch (error) {
          console.error('[bundle-ui] Error during rebundle:', error);
        }
      }, 500);
    }
  }
}

// Main entry point
const args = Deno.args;
const isWatch = args.includes('--watch') || args.includes('-w');

if (isWatch) {
  await watchMode();
} else {
  await bundleUI();
}