import { basename } from 'path';
import { isBinaryPath } from './tools/binary-extensions';
import { visitNotIgnoredFiles } from './tools/visit-not-ignored-files';
import { readFileSync, writeFileSync } from 'fs';
import { log } from '@clack/prompts';

function updateFileContent(path: string, content: string) {
  writeFileSync(path, content);
  log.info(`"${path}" has been updated`);
}

export function replacePackage(
  oldPackageName: string,
  newPackageName: string,
  skipDependencies = false
): void {
  if (!skipDependencies) {
    replacePackageInDependencies(oldPackageName, newPackageName);
  }

  replaceMentions(oldPackageName, newPackageName);
}

function replacePackageInDependencies(oldPackageName: string, newPackageName: string) {
  visitNotIgnoredFiles('.', (path) => {
    if (basename(path) !== 'package.json') {
      return;
    }

    try {
      const packageJson = JSON.parse(readFileSync(path, 'utf-8'));
      const dependencies = [
        packageJson.dependencies ?? {},
        packageJson.devDependencies ?? {},
        packageJson.peerDependencies ?? {},
        packageJson.optionalDependencies ?? {},
      ];
      for (let i = 0; i < dependencies.length; i++) {
        const deps = dependencies[i];
        if (oldPackageName in deps) {
          // We keep the old version intentionally. It will be updated later within another step of the migration.
          deps[newPackageName] = deps[oldPackageName];
          delete deps[oldPackageName];
        }
      }
      updateFileContent(path, JSON.stringify(packageJson, null, 2));
    } catch (e) {
      console.warn(`Could not replace ${oldPackageName} with ${newPackageName} in ${path}.`);
    }
  });
}

function replaceMentions(oldPackageName: string, newPackageName: string) {
  visitNotIgnoredFiles('.', (path) => {
    if (isBinaryPath(path)) {
      return;
    }

    const ignoredFiles = [
      'yarn.lock',
      'package-lock.json',
      'pnpm-lock.yaml',
      'bun.lockb',
      'CHANGELOG.md',
    ];
    if (ignoredFiles.includes(basename(path))) {
      return;
    }

    try {
      const contents = readFileSync(path, 'utf-8');

      if (!contents.includes(oldPackageName)) {
        return;
      }

      updateFileContent(path, contents.replace(new RegExp(oldPackageName, 'g'), newPackageName));
    } catch {
      // Its **probably** ok, contents can be null if the file is too large or
      // there was an access exception.
      log.warn(
        `An error was thrown when trying to update ${path}. If you believe the migration should have updated it, be sure to review the file and open an issue.`
      );
    }
  });
}
