/*
 * (c) Copyright IBM Corp. 2021
 * (c) Copyright Instana Inc. and contributors 2018
 */

'use strict';

const fs = require('fs');

const { applicationUnderMonitoring } = require('@supertenant/core').util;

let logger = require('@supertenant/core').logger.getLogger('metrics');

/**
 * @param {import('@supertenant/core/src/logger').GenericLogger} _logger
 */
exports.setLogger = function setLogger(_logger) {
  logger = _logger;
};

exports.payloadPrefix = 'directDependencies';

/** @type {Object.<string, *>} */
exports.currentPayload = {
  dependencies: {},
  peerDependencies: {},
  optionalDependencies: {}
};

const MAX_ATTEMPTS = 20;
const DELAY = 1000;
let attempts = 0;

exports.activate = function activate() {
  attempts++;
  applicationUnderMonitoring.getMainPackageJsonPathStartingAtMainModule((err, packageJsonPath) => {
    if (err) {
      return logger.info(
        'Failed to determine main package.json for analysis of direct dependencies. Reason: %s %s ',
        err.message,
        err.stack
      );
    } else if (!packageJsonPath && attempts < MAX_ATTEMPTS) {
      setTimeout(exports.activate, DELAY).unref();
      return;
    } else if (!packageJsonPath) {
      // final attempt failed, ignore silently
      return;
    }

    addDirectDependenciesFromMainPackageJson(packageJsonPath);
  });
};

/**
 * @param {string} packageJsonPath
 */
function addDirectDependenciesFromMainPackageJson(packageJsonPath) {
  const started = Date.now();
  fs.readFile(packageJsonPath, { encoding: 'utf8' }, (err, contents) => {
    if (err) {
      return logger.debug('Failed to analyze direct dependencies dependency due to: %s.', err.message);
    }

    try {
      const pckg = JSON.parse(contents);
      exports.currentPayload.dependencies = pckg.dependencies || {};
      exports.currentPayload.peerDependencies = pckg.peerDependencies || {};
      exports.currentPayload.optionalDependencies = pckg.optionalDependencies || {};
      exports.currentPayload[pckg.name] = pckg.version;
      logger.debug(`Collection of direct dependencies took ${Date.now() - started} ms.`);
    } catch (subErr) {
      logger.debug(`Collection of direct dependencies took ${Date.now() - started} ms.`);
      return logger.debug('Failed to parse package.json %s dependency due to: %s', packageJsonPath, subErr.message);
    }
  });
}