/** Builds the userscript using esbuild.
 * This will:
 * 1. Update the package version across the entire project
 * 2. Bundle the JS files into one file (esbuild)
 * 3. Bundle the CSS files into one file (esbuild)
 * 4. Compress & obfuscate the bundled JS file (terner)
 * 5. Runs the CSS selector mangler (cssMandler.js)
 * @since 0.0.6
 */

// ES Module imports
import esbuild from "esbuild";
import fs from "fs";
import { execSync } from "child_process";
import { consoleStyle } from "./utils.js";
import { createRequire } from "module";
import { minify } from "html-minifier-terser";
const require = createRequire(import.meta.url);
// CommonJS imports (require)
const terser = require("terser");

const isGitHub = !!process.env?.GITHUB_ACTIONS; // Is this running in a GitHub Action Workflow?'
console.log(`${consoleStyle.BLUE}Starting build...${consoleStyle.RESET}`);

// Tries to build the wiki if build.js is run in a GitHub Workflow
// if (isGitHub) {
//   try {
//     console.log(`Generating JSDoc...`);
//     execSync(`npx jsdoc src/ -r -d docs -t node_modules/minami`, { stdio: "inherit" });
//     console.log(`JSDoc built ${consoleStyle.GREEN}successfully${consoleStyle.RESET}`);
//   } catch (error) {
//     console.error(`${consoleStyle.RED + consoleStyle.BOLD}Failed to generate JSDoc${consoleStyle.RESET}:`, error);
//     process.exit(1);
//   }
// }

// Tries to bump the version
try {
  execSync('node build/update-version.js', { stdio: 'inherit' });
} catch (error) {
  console.error(`${consoleStyle.RED + consoleStyle.BOLD}Failed to update version number${consoleStyle.RESET}:`, error);
  process.exit(1);
}

// Gets a string array of all CSS files
const cssFiles = fs.readdirSync('src/')
  .filter(file => file.endsWith('.css'))
  .map(file => `src/${file}`);

// Compiles the CSS files
esbuild.build({
  entryPoints: cssFiles,
  bundle: true,
  outfile: 'dist/BlueMarble.user.css',
  minify: true
});

const miniCSS = fs.readFileSync('dist/BlueMarble.user.css', 'utf-8')
// A piece of code injected into the outputted JS file that injects the CSS into the page
const cssAttachCode = `
  const miniCSSStyleElem = document.createElement("style");
  miniCSSStyleElem.textContent=\`${miniCSS}\`;
  document.body.appendChild(miniCSSStyleElem);
`
const attachCodes = [cssAttachCode]

// Gets a string array of all HTML files in src
fs.readdirSync('src/')
  .filter(file => file.endsWith('.html'))
  .map(file => `src/${file}`)
  .forEach(filePath => {
    const html = fs.readFileSync(filePath, 'utf-8')
    if(!html.startsWith('<!--')){
      console.log(`${consoleStyle.RED}HTML file '${filePath}' doesn't start with a comment about its inject location${consoleStyle.RESET}`)
    }else{
      // Extract only the css query of where to attach this html
      const cssQuery = html.slice(4, html.indexOf('-->')).trim() 
      // Pushes a piece of code that injects the html into the page
      attachCodes.push(`document.querySelector("${cssQuery}").innerHTML += \`${html}\`;`);
    }
  })

// Gets the current 
let code = fs.readFileSync('src/main.ts', 'utf-8')
const originalCode = code;
// Inject the codes that inject CSS / HTML into the page
code = attachCodes.join('\n') + code;
// Write the altered file data back into a file
fs.writeFileSync('src/main.ts', code, { flag: 'w+' })

// Compiles the JS files
const resultEsbuild = await esbuild.build({
  entryPoints: ['src/main.ts'], // "Infect" the files from this point (it spreads from this "patient 0")
  bundle: true, // Should the code be bundled?
  outfile: 'dist/BlueMarble.user.js', // The file the bundled code is exported to
  format: 'iife', // What format the bundler bundles the code into
  target: 'es2020', // What is the minimum version/year that should be supported? When omited, it attempts to support backwards compatability with legacy browsers
  platform: 'browser', // The platform the bundled code will be operating on
  legalComments: 'inline', // What level of legal comments are preserved? (Hard: none, Soft: inline)
  minify: false, // Should the code be minified?
  write: false, // Should we write the outfile to the disk?
}).catch(() => process.exit(1));

// Retrieves the JS file
const resultEsbuildJS = resultEsbuild.outputFiles.find(file => file.path.endsWith('.js'));

// Obfuscates the JS file
let resultTerser = await terser.minify(resultEsbuildJS.text, {
  mangle: {
    //toplevel: true, // Obfuscate top-level class/function names
    keep_classnames: false, // Should class names be preserved?
    keep_fnames: false, // Should function names be preserved?
    reserved: [], // List of keywords to preserve
    properties: {
      // regex: /.*/, // Yes, I am aware I should be using a RegEx. Yes, like you, I am also suprised the userscript still functions
      keep_quoted: true, // Should names in quotes be preserved?
      reserved: [] // What properties should be preserved?
    },
  },
  format: {
    comments: 'some' // Save legal comments
  },
  compress: {
    dead_code: isGitHub, // Should unreachable code be removed?
    drop_console: isGitHub, // Should console code be removed?
    drop_debugger: isGitHub, // SHould debugger code be removed?
    passes: 2 // How many times terser will compress the code
  }
});

// Writes the obfuscated/mangled JS code to a file
fs.writeFileSync('dist/BlueMarble.user.js', resultTerser.code, 'utf8');

let importedMapCSS = {}; // The imported CSS map

// Only import a CSS map if we are NOT in production (GitHub Workflow)
// Theoretically, if the previous map is always imported, the names would not scramble. However, the names would never decrease in number...
if (!isGitHub) {
  try {
    importedMapCSS = JSON.parse(fs.readFileSync('dist/BlueMarble.user.css.map.json', 'utf8'));
  } catch {
    console.log(`${consoleStyle.YELLOW}Warning! Could not find a CSS map to import. A 100% new CSS map will be generated...${consoleStyle.RESET}`);
  }
}

// Mangles the CSS selectors
// If we are in production (GitHub Workflow), then generate the CSS mapping
// const mapCSS = mangleSelectors({
//   inputPrefix: 'bm-',
//   outputPrefix: 'bm-',
//   pathJS: 'dist/BlueMarble.user.js',
//   pathCSS: 'dist/BlueMarble.user.css',
//   importMap: importedMapCSS,
//   returnMap: isGitHub
// });

// If a map was returned, write it to the file
// if (mapCSS) {
//   fs.writeFileSync('dist/BlueMarble.user.css.map.json', JSON.stringify(mapCSS, null, 2));
// }

// Adds the banner
fs.writeFileSync(
  'dist/index.js', 
  "(function (){ return ({ patches: [], load: () => {" + resultTerser.code + "},});})();", 
  'utf8'
);
fs.writeFileSync('src/main.ts', originalCode)
console.log(`${consoleStyle.GREEN + consoleStyle.BOLD + consoleStyle.UNDERLINE}Building complete!${consoleStyle.RESET}`);