text: 'use strict'
  var url = require('url')
  var gitHosts = require('./git-host-info.js')
  var GitHost = module.exports = require('./git-host.js')
  
  var protocolToRepresentationMap = {
    'git+ssh': 'sshurl',
    'git+https': 'https',
    'ssh': 'sshurl',
    'git': 'git'
  }
  
  function protocolToRepresentation (protocol) {
    if (protocol.substr(-1) === ':') protocol = protocol.slice(0, -1)
    return protocolToRepresentationMap[protocol] || protocol
  }
  
  var authProtocols = {
    'git:': true,
    'https:': true,
    'git+https:': true,
    'http:': true,
    'git+http:': true
  }
  
  var cache = {}
  
  module.exports.fromUrl = function (giturl, opts) {
    if (typeof giturl !== 'string') return
    var key = giturl + JSON.stringify(opts || {})
  
    if (!(key in cache)) {
      cache[key] = fromUrl(giturl, opts)
    }
  
    return cache[key]
  }
  
  function fromUrl (giturl, opts) {
    if (giturl == null || giturl === '') return
    var url = fixupUnqualifiedGist(
      isGitHubShorthand(giturl) ? 'github:' + giturl : giturl
    )
    var parsed = parseGitUrl(url)
    var shortcutMatch = url.match(new RegExp('^([^:]+):(?:(?:[^@:]+(?:[^@]+)?@)?([^/]*))[/](.+?)(?:[.]git)?($|#)'))
    var matches = Object.keys(gitHosts).map(function (gitHostName) {
      try {
        var gitHostInfo = gitHosts[gitHostName]
        var auth = null
        if (parsed.auth && authProtocols[parsed.protocol]) {
          auth = decodeURIComponent(parsed.auth)
        }
        var committish = parsed.hash ? decodeURIComponent(parsed.hash.substr(1)) : null
        var user = null
        var project = null
        var defaultRepresentation = null
        if (shortcutMatch && shortcutMatch[1] === gitHostName) {
          user = shortcutMatch[2] && decodeURIComponent(shortcutMatch[2])
          project = decodeURIComponent(shortcutMatch[3])
          defaultRepresentation = 'shortcut'
        } else {
          if (parsed.host && parsed.host !== gitHostInfo.domain && parsed.host.replace(/^www[.]/, '') !== gitHostInfo.domain) return
          if (!gitHostInfo.protocols_re.test(parsed.protocol)) return
          if (!parsed.path) return
          var pathmatch = gitHostInfo.pathmatch
          var matched = parsed.path.match(pathmatch)
          if (!matched) return
          if (matched[1] != null) user = decodeURIComponent(matched[1].replace(/^:/, ''))
          if (matched[2] != null) project = decodeURIComponent(matched[2])
          defaultRepresentation = protocolToRepresentation(parsed.protocol)
        }
        return new GitHost(gitHostName, user, auth, project, committish, defaultRepresentation, opts)
      } catch (ex) {
        if (!(ex instanceof URIError)) throw ex
      }
    }).filter(function (gitHostInfo) { return gitHostInfo })
    if (matches.length !== 1) return
    return matches[0]
  }
  
  function isGitHubShorthand (arg) {
    // Note: This does not fully test the git ref format.
    // See https://www.kernel.org/pub/software/scm/git/docs/git-check-ref-format.html
    //
    // The only way to do this properly would be to shell out to
    // git-check-ref-format, and as this is a fast sync function,
    // we don't want to do that.  Just let git fail if it turns
    // out that the commit-ish is invalid.
    // GH usernames cannot start with . or -
    return /^[^:@%/\s.-][^:@%/\s]*[/][^:@\s/%]+(?:#.*)?$/.test(arg)
  }
  
  function fixupUnqualifiedGist (giturl) {
    // necessary for round-tripping gists
    var parsed = url.parse(giturl)
    if (parsed.protocol === 'gist:' && parsed.host && !parsed.path) {
      return parsed.protocol + '/' + parsed.host
    } else {
      return giturl
    }
  }
  
  function parseGitUrl (giturl) {
    if (typeof giturl !== 'string') giturl = '' + giturl
    var matched = giturl.match(/^([^@]+)@([^:/]+):[/]?((?:[^/]+[/])?[^/]+?)(?:[.]git)?(#.*)?$/)
    if (!matched) return url.parse(giturl)
    return {
      protocol: 'git+ssh:',
      slashes: true,
      auth: matched[1],
      host: matched[2],
      port: null,
      hostname: matched[2],
      hash: matched[4],
      search: null,
      query: null,
      pathname: '/' + matched[3],
      path: '/' + matched[3],
      href: 'git+ssh://' + matched[1] + '@' + matched[2] +
            '/' + matched[3] + (matched[4] || '')
    }
  }
  