#!/usr/bin/env node
// Standalone semver comparison program.
// Exits successfully and prints matching version(s) if
// any supplied version is valid and passes all tests.

var argv = process.argv.slice(2)
  , versions = []
  , range = []
  , gt = []
  , lt = []
  , eq = []
  , inc = null
  , version = require("../package.json").version
  , loose = false
  , semver = require("../semver")
  , reverse = false

main()

function main () {
  if (!argv.length) return help()
  while (argv.length) {
    var a = argv.shift()
    var i = a.indexOf('=')
    if (i !== -1) {
      a = a.slice(0, i)
      argv.unshift(a.slice(i + 1))
    }
    switch (a) {
      case "-rv": case "-rev": case "--rev": case "--reverse":
        reverse = true
        break
      case "-l": case "--loose":
        loose = true
        break
      case "-v": case "--version":
        versions.push(argv.shift())
        break
      case "-i": case "--inc": case "--increment":
        switch (argv[0]) {
          case "major": case "minor": case "patch": case "prerelease":
          case "premajor": case "preminor": case "prepatch":
            inc = argv.shift()
            break
          default:
            inc = "patch"
            break
        }
        break
      case "-r": case "--range":
        range.push(argv.shift())
        break
      case "-h": case "--help": case "-?":
        return help()
      default:
        versions.push(a)
        break
    }
  }

  versions = versions.filter(function (v) {
    return semver.valid(v, loose)
  })
  if (!versions.length) return fail()
  if (inc && (versions.length !== 1 || range.length))
    return failInc()

  for (var i = 0, l = range.length; i < l ; i ++) {
    versions = versions.filter(function (v) {
      return semver.satisfies(v, range[i], loose)
    })
    if (!versions.length) return fail()
  }
  return success(versions)
}

function failInc () {
  console.error("--inc can only be used on a single version with no range")
  fail()
}

function fail () { process.exit(1) }

function success () {
  var compare = reverse ? "rcompare" : "compare"
  versions.sort(function (a, b) {
    return semver[compare](a, b, loose)
  }).map(function (v) {
    return semver.clean(v, loose)
  }).map(function (v) {
    return inc ? semver.inc(v, inc, loose) : v
  }).forEach(function (v,i,_) { console.log(v) })
}

function help () {
  console.log(["SemVer " + version
              ,""
              ,"A JavaScript implementation of the http://semver.org/ specification"
              ,"Copyright Isaac Z. Schlueter"
              ,""
              ,"Usage: semver [options] <version> [<version> [...]]"
              ,"Prints valid versions sorted by SemVer precedence"
              ,""
              ,"Options:"
              ,"-r --range <range>"
              ,"        Print versions that match the specified range."
              ,""
              ,"-i --increment [<level>]"
              ,"        Increment a version by the specified level.  Level can"
              ,"        be one of: major, minor, patch, or prerelease"
              ,"        Default level is 'patch'."
              ,"        Only one version may be specified."
              ,""
              ,"-l --loose"
              ,"        Interpret versions and ranges loosely"
              ,""
              ,"Program exits successfully if any valid version satisfies"
              ,"all supplied ranges, and prints all satisfying versions."
              ,""
              ,"If no satisfying versions are found, then exits failure."
              ,""
              ,"Versions are printed in ascending order, so supplying"
              ,"multiple versions to the utility will just sort them."
              ].join("\n"))
}
