'use strict'

const Joi = require('joi')
const BaseJsonService = require('../base-json')
const { InvalidResponse } = require('../errors')
const { nonNegativeInteger, anyInteger } = require('../validators')

// API doc: https://libraries.io/api#project
// We distinguishb between packages and repos based on the presence of the
// `platform` key.
const packageSchema = Joi.object({
  platform: Joi.string().required(),
  dependents_count: nonNegativeInteger,
  dependent_repos_count: nonNegativeInteger,
  rank: anyInteger,
}).required()

const repoSchema = Joi.object({
  platform: Joi.any().forbidden(),
}).required()

const packageOrRepoSchema = Joi.alternatives(repoSchema, packageSchema)

class LibrariesIoBase extends BaseJsonService {
  static buildUrl(base) {
    return {
      base,
      format: '(\\w+)/(.+)',
      capture: ['platform', 'packageName'],
    }
  }

  async fetch({ platform, packageName }, { allowPackages, allowRepos } = {}) {
    const json = await this._requestJson({
      schema: packageOrRepoSchema,
      url: `https://libraries.io/api/${platform}/${packageName}`,
      errorMessages: { 404: 'package not found' },
    })
    const isPackage = Boolean(json.platform)
    if (isPackage && !allowPackages) {
      throw new InvalidResponse({ prettyMessage: 'not supported for packages' })
    }
    if (!isPackage && !allowRepos) {
      throw new InvalidResponse({ prettyMessage: 'not supported for repos' })
    }
    return json
  }
}

module.exports = LibrariesIoBase