module.exports = {
  env: {
    browser: true,
    es2021: true,
  },
  extends: [
    'eslint:recommended',
    'plugin:react/recommended',
    'plugin:react-hooks/recommended',
    'plugin:@typescript-eslint/eslint-recommended',
    'plugin:@typescript-eslint/recommended',
    'airbnb',
    'prettier',
  ],
  parser: '@typescript-eslint/parser',
  parserOptions: {
    ecmaFeatures: {
      jsx: true,
    },
    ecmaVersion: 'latest',
    sourceType: 'module',
  },
  globals: {
    JSX: 'readonly',
    __APP_VERSION__: 'readonly',
  },
  plugins: ['react', '@typescript-eslint'],
  rules: {
    'linebreak-style': 0,
    'no-underscore-dangle': 0,
    'no-shadow': 'off',

    'import/prefer-default-export': 'off',
    'import/extensions': 'off',
    'import/no-unresolved': 'off',
    'import/no-extraneous-dependencies': [
      'error',
      {
        devDependencies: true,
      },
    ],

    'react/no-unstable-nested-components': ['error', { allowAsProps: true }],
    'react/jsx-filename-extension': [
      'error',
      {
        extensions: ['.tsx', '.jsx'],
      },
    ],

    'react/require-default-props': 'off',
    'react/jsx-props-no-spreading': 'off',
    'react-hooks/rules-of-hooks': 'error',
    'react-hooks/exhaustive-deps': 'error',

    // Disable base rules in favour of their @typescript-eslint counterparts —
    // the base rules can't see TS-specific constructs (interface members, type
    // imports, etc.) and double-fire alongside the TS versions.
    'no-unused-vars': 'off',
    '@typescript-eslint/no-unused-vars': ['error', { argsIgnorePattern: '^_' }],
    '@typescript-eslint/no-shadow': 'error',

    // Policy: kept as warnings, not errors. The codebase has ~70 long-standing
    // `any` casts and ~15 non-null assertions in matrix-js-sdk interop code.
    // Promoting to error would block builds on existing usage; turning off
    // would lose signal on new code. Warnings are visible without blocking.
    '@typescript-eslint/no-explicit-any': 'warn',
    '@typescript-eslint/no-non-null-assertion': 'warn',
  },
  overrides: [
    {
      files: ['*.ts', '*.tsx'],
      rules: {
        'no-undef': 'off',
      },
    },
    {
      // Upstream-vendored binary parsing copied verbatim from matrix-react-sdk
      // (src/util/cryptE2ERoomKeys.js header link). Bitwise ops, post-increment
      // and string concatenation are correct for the domain — clean-up risks
      // breaking E2E room-key import/export. Keep the body byte-identical to
      // upstream and disable only the rules that fire on those idioms.
      files: ['src/util/cryptE2ERoomKeys.js'],
      rules: {
        'no-bitwise': 'off',
        'no-plusplus': 'off',
        'prefer-template': 'off',
        'no-param-reassign': 'off',
      },
    },
  ],
};