const pluginConfig = require('../pluginConfig.json');
const fs = require('fs');

const autogenerationDisclaimer = `
// THIS FILE IS AUTOGENERATED AS PART OF THE EXTENSION AND MODE PLUGIN PROCESS.
// IT SHOULD NOT BE MODIFIED MANUALLY \n`;

function constructLines(input, categoryName) {
  let pluginCount = 0;

  const lines = {
    importLines: [],
    addToWindowLines: [],
  };

  if (!input) return lines;

  input.forEach(entry => {
    const packageName = entry.packageName;

    const defaultImportName = `${categoryName}${pluginCount}`;

    lines.importLines.push(
      `import ${defaultImportName} from '${packageName}';\n`
    );
    lines.addToWindowLines.push(
      `${categoryName}.push(${defaultImportName});\n`
    );

    pluginCount++;
  });

  return lines;
}

function getFormattedImportBlock(importLines) {
  let content = '';
  // Imports
  importLines.forEach(importLine => {
    content += importLine;
  });

  return content;
}

function getFormattedWindowBlock(addToWindowLines) {
  let content = "const extensions = [];\n" +
    "const modes = [];\n" +
    "const modesFactory = [];\n" +
    "window.extensions = extensions;\n" +
    "window.modes = modes;\n\n";

  addToWindowLines.forEach(addToWindowLine => {
    content += addToWindowLine;
  });

  return content;
}

function getRuntimeLoadModesExtensions() {
  return "\n\n// Add a dynamic runtime loader\n" +
    "export default async () => {\n" +
    " for(const modeFactory of modesFactory) {\n" +
    "  const newModes = await modeFactory(modes,extensions);\n" +
    "  newModes.forEach(newMode => modes.push(newMode));\n" +
    "}\n}\n";
}

const createCopyPluginFromExtensions = (SRC_DIR, DIST_DIR, plugins) => {

  return plugins.map(plugin => {
    const from = `${SRC_DIR}/../node_modules/${plugin.packageName}/public/`;
    const exists = fs.existsSync(from);
    return exists ? {
      from,
      to: DIST_DIR,
      toType: 'dir',
    } : undefined;
  }
  ).filter(x => !!x);
}

function writePluginImportsFile(SRC_DIR, DIST_DIR) {
  let pluginImportsJsContent = autogenerationDisclaimer;

  const extensionLines = constructLines(pluginConfig.extensions, 'extensions');
  const modeLines = constructLines(pluginConfig.modes, 'modes');
  const modesFactoryLines = constructLines(pluginConfig.modesFactory, 'modesFactory');

  pluginImportsJsContent += getFormattedImportBlock([
    ...extensionLines.importLines,
    ...modeLines.importLines,
    ...modesFactoryLines.importLines,
  ]);
  pluginImportsJsContent += getFormattedWindowBlock([
    ...extensionLines.addToWindowLines,
    ...modeLines.addToWindowLines,
    ...modesFactoryLines.addToWindowLines,
  ]);

  pluginImportsJsContent += getRuntimeLoadModesExtensions();

  fs.writeFileSync(
    `${SRC_DIR}/pluginImports.js`,
    pluginImportsJsContent,
    { flag: 'w+' },
    err => {
      if (err) {
        console.error(err);
        return;
      }
    }
  );

  const copyPluginFromExtensions = createCopyPluginFromExtensions(
    SRC_DIR, DIST_DIR,
    [
      ...pluginConfig.modesFactory,
      ...pluginConfig.modes,
      ...pluginConfig.extensions,
      ...pluginConfig.umd,
    ]
  )

  return copyPluginFromExtensions;
}

module.exports = writePluginImportsFile;