// tslint:disable no-console

import { readFileSync } from 'fs';
import { join, relative } from 'path';

// @ts-ignore
import glob from 'glob';
import { forEach, some, values } from 'lodash';

import { ExceptionType, REASONS, RuleType } from './types';
import { ENCODING, loadJSON } from './util';

const ALL_REASONS = REASONS.join('|');
const now = new Date();

function getExceptionKey(exception: any) {
  return `${exception.rule}-${exception.path}-${exception.lineNumber}`;
}

function createLookup(list: Array<any>) {
  const lookup = Object.create(null);

  forEach(list, exception => {
    const key = getExceptionKey(exception);

    if (lookup[key]) {
      throw new Error(`Duplicate exception found for key ${key}`);
    }

    lookup[key] = exception;
  });

  return lookup;
}

const rulesPath = join(__dirname, 'rules.json');
const exceptionsPath = join(__dirname, 'exceptions.json');
const basePath = join(__dirname, '../../..');

const searchPattern = join(basePath, '**/*.{js,ts,tsx}');

const rules: Array<RuleType> = loadJSON(rulesPath);
const exceptions: Array<ExceptionType> = loadJSON(exceptionsPath);
const exceptionsLookup = createLookup(exceptions);
let scannedCount = 0;

const allSourceFiles = glob.sync(searchPattern, { nodir: true });

const results: Array<ExceptionType> = [];

const excludedFiles = [
  // Generated files
  '^js/components.js',
  '^js/libtextsecure.js',
  '^js/util_worker.js',
  '^libtextsecure/components.js',
  '^libtextsecure/test/test.js',
  '^test/test.js',

  // From libsignal-protocol-javascript project
  '^js/libsignal-protocol-worker.js',
  '^libtextsecure/libsignal-protocol.js',

  // Copied from dependency
  '^js/Mp3LameEncoder.min.js',

  // Test files
  '^libtextsecure/test/*',
  '^test/*',

  // Modules used only in test/development scenarios
  '^node_modules/@types/*',
  '^node_modules/ajv/*',
  '^node_modules/amdefine/*',
  '^node_modules/anymatch/*',
  '^node_modules/asn1\\.js/*',
  '^node_modules/autoprefixer/*',
  '^node_modules/babel*',
  '^node_modules/bluebird/*',
  '^node_modules/body-parser/*',
  '^node_modules/bower/*',
  '^node_modules/buble/*',
  '^node_modules/chai/*',
  '^node_modules/cli-table2/*',
  '^node_modules/codemirror/*',
  '^node_modules/coffee-script/*',
  '^node_modules/compression/*',
  '^node_modules/degenerator/*',
  '^node_modules/detect-port-alt/*',
  '^node_modules/electron-builder/*',
  '^node_modules/electron-icon-maker/*',
  '^node_modules/electron-osx-sign/*',
  '^node_modules/electron-publish/*',
  '^node_modules/escodegen/*',
  '^node_modules/eslint*',
  '^node_modules/esprima/*',
  '^node_modules/express/*',
  '^node_modules/extract-zip/*',
  '^node_modules/finalhandler/*',
  '^node_modules/fsevents/*',
  '^node_modules/globule/*',
  '^node_modules/grunt*',
  '^node_modules/handle-thing/*',
  '^node_modules/har-validator/*',
  '^node_modules/highlight\\.js/*',
  '^node_modules/hpack\\.js/*',
  '^node_modules/http-proxy-middlewar/*',
  '^node_modules/icss-utils/*',
  '^node_modules/intl-tel-input/examples/*',
  '^node_modules/istanbul*',
  '^node_modules/jimp/*',
  '^node_modules/jquery/*',
  '^node_modules/jss/*',
  '^node_modules/jss-global/*',
  '^node_modules/livereload-js/*',
  '^node_modules/lolex/*',
  '^node_modules/magic-string/*',
  '^node_modules/mocha/*',
  '^node_modules/minimatch/*',
  '^node_modules/nise/*',
  '^node_modules/node-sass-import-once/*',
  '^node_modules/node-sass/*',
  '^node_modules/nsp/*',
  '^node_modules/nyc/*',
  '^node_modules/phantomjs-prebuilt/*',
  '^node_modules/postcss*',
  '^node_modules/preserve/*',
  '^node_modules/prettier/*',
  '^node_modules/protobufjs/cli/*',
  '^node_modules/ramda/*',
  '^node_modules/react-docgen/*',
  '^node_modules/react-error-overlay/*',
  '^node_modules/react-styleguidist/*',
  '^node_modules/recast/*',
  '^node_modules/reduce-css-calc/*',
  '^node_modules/resolve/*',
  '^node_modules/sass-graph/*',
  '^node_modules/scss-tokenizer/*',
  '^node_modules/send/*',
  '^node_modules/serve-index/*',
  '^node_modules/sinon/*',
  '^node_modules/snapdragon-util/*',
  '^node_modules/snapdragon/*',
  '^node_modules/sockjs-client/*',
  '^node_modules/spectron/*',
  '^node_modules/style-loader/*',
  '^node_modules/svgo/*',
  '^node_modules/testcheck/*',
  '^node_modules/text-encoding/*',
  '^node_modules/tinycolor2/*',
  '^node_modules/to-ast/*',
  '^node_modules/trough/*',
  '^node_modules/ts-loader/*',
  '^node_modules/tslint*',
  '^node_modules/tweetnacl/*',
  '^node_modules/typescript/*',
  '^node_modules/uglify-es/*',
  '^node_modules/uglify-js/*',
  '^node_modules/use/*',
  '^node_modules/vary/*',
  '^node_modules/vm-browserify/*',
  '^node_modules/webdriverio/*',
  '^node_modules/webpack*',
  '^node_modules/xmldom/*',
  '^node_modules/xml-parse-from-string/*',
];

function setupRules(allRules: Array<RuleType>) {
  forEach(allRules, (rule, index) => {
    if (!rule.name) {
      throw new Error(`Rule at index ${index} is missing a name`);
    }

    if (!rule.expression) {
      throw new Error(`Rule '${rule.name}' is missing an expression`);
    }

    rule.regex = new RegExp(rule.expression, 'g');
  });
}

setupRules(rules);

forEach(allSourceFiles, file => {
  const relativePath = relative(basePath, file).replace(/\\/g, '/');
  if (
    some(excludedFiles, excluded => {
      const regex = new RegExp(excluded);

      return regex.test(relativePath);
    })
  ) {
    return;
  }

  scannedCount += 1;

  const fileContents = readFileSync(file, ENCODING);
  const lines = fileContents.split('\n');

  forEach(rules, (rule: RuleType) => {
    const excludedModules = rule.excludedModules || [];
    if (some(excludedModules, module => relativePath.startsWith(module))) {
      return;
    }

    forEach(lines, (rawLine, lineIndex) => {
      const line = rawLine.replace(/\r/g, '');
      if (!rule.regex.test(line)) {
        return;
      }

      const path = relativePath;
      const lineNumber = lineIndex + 1;

      const exceptionKey = getExceptionKey({
        rule: rule.name,
        path: relativePath,
        lineNumber,
      });

      const exception = exceptionsLookup[exceptionKey];
      if (exception && (!exception.line || exception.line === line)) {
        delete exceptionsLookup[exceptionKey];

        return;
      }

      results.push({
        rule: rule.name,
        path,
        line: line.length < 300 ? line : undefined,
        lineNumber,
        reasonCategory: ALL_REASONS,
        updated: now.toJSON(),
        reasonDetail: '<optional>',
      });
    });
  });
});

const unusedExceptions = values(exceptionsLookup);

console.log(
  `${scannedCount} files scanned.`,
  `${results.length} questionable lines,`,
  `${unusedExceptions.length} unused exceptions,`,
  `${exceptions.length} total exceptions.`
);

if (results.length === 0 && unusedExceptions.length === 0) {
  process.exit();
}

console.log();
console.log('Questionable lines:');
console.log(JSON.stringify(results, null, '  '));

if (unusedExceptions.length) {
  console.log();
  console.log('Unused exceptions!');
  console.log(JSON.stringify(unusedExceptions, null, '  '));
}

process.exit(1);