gut

#!/usr/bin/env ruby
# encoding: utf-8

require 'optparse'
require 'colorize'

# helps adopting good practices and pushing clean code
# features :
# - prevents from coding directly into dev
# - prevents from pushing breaking code into dev
# - helps you setting up a standadised working process

# I also use those aliases to make things faster :
#
# alias gc='gut -c'
# alias gf='gut -f'
# alias gp='gut -p'
# alias gu='gut -u'
# alias gh='gut -h'
# alias gr='gut -r'
# alias gv='gut -v'
# alias fix='git add -A;git commit --amend --no-edit'

FEATURE_COMMIT_PREFIX = 'feature-'
REFERENCE_BRANCH_NAME = 'dev'
CURRENT_BRANCH = `git rev-parse --abbrev-ref HEAD`.delete("\n")
TESTS_COMMAND = 'echo "no tests to be run"' # in a rails app it would be something like 'rake test'

#-------------- START HELPERS ----------------
class String
  def is_integer?
    self.to_i.to_s == self
  end

  def is_positive_integer?
    self.is_integer? && self.to_i >= 0
  end
end

def error(isSuccess, message)
  unless isSuccess then
    puts "ERROR: #{message}".red
    exit
  end
end

def success(message)
  puts message.green
end

def generateFullCommitMessage(currentBranch, message)
  "#{CURRENT_BRANCH}: #{message}"
end

def generateFullFeatureBranchName(name)
  "#{FEATURE_COMMIT_PREFIX}#{name}"
end

def isWorkingDirectoryClean
  `git status --porcelain`.empty?
end

def isCurrentBranchFeature
  #TODO: also check if it descends directly from REFERENCE_BRANCH_NAME branch
  CURRENT_BRANCH.start_with?(FEATURE_COMMIT_PREFIX)
end

def isCurrentBranchReferenceBranch
  #TODO: also check if it descends directly from REFERENCE_BRANCH_NAME branch
  CURRENT_BRANCH == REFERENCE_BRANCH_NAME
end

def isBranchOnlyLocal
  #TODO: also check if it descends directly from REFERENCE_BRANCH_NAME branch
  CURRENT_BRANCH.start_with?(FEATURE_COMMIT_PREFIX)
end
#-------------- END HELPERS ----------------

#-------------- START OPTIONS LOGIC ----------------

def optionPrune
  # check if current branch is a feature
  error(isCurrentBranchFeature, 'You cannot commit from something else than a feature branch')
  # check if working directory clean
  error(isWorkingDirectoryClean, 'Working directory is not clean')
  # test your modifications with the changes of the reference branch
  error(system('git fetch'), 'Error fetching from origin')
  error(system("git merge #{REFERENCE_BRANCH_NAME} -m \"Applying finished feature #{CURRENT_BRANCH}\""), 'Error merging')
  error(system(TESTS_COMMAND), 'The tests are not passing, please fix and try again')
  # apply your modifications and remove the feature branch
  error(system("git checkout #{REFERENCE_BRANCH_NAME}"), "Failed to checkout #{REFERENCE_BRANCH_NAME}")
  error(system("git merge #{CURRENT_BRANCH}"), "Failed to merge your work on #{REFERENCE_BRANCH_NAME}")
  error(system("git branch -d #{CURRENT_BRANCH}"), "Failed to remove your feature branch")
  error(system("git push"), "Failed to push the changes")

  success "Feature successfully applied to #{REFERENCE_BRANCH_NAME}"
end

def optionUpdate#check if working directory clean?
  # check if current branch is a feature
  error(isCurrentBranchFeature, 'You cannot update something else than a feature branch')
  # integrate changes from the reference branch
  error(system("git rebase #{REFERENCE_BRANCH_NAME}"), 'Error rebasing')

  success "Feature successfully updated with #{REFERENCE_BRANCH_NAME} changes"
end

def optionFeature
  def isfeatureNameValid(name)
    !name.start_with? FEATURE_COMMIT_PREFIX
  end

  def createNewFeature(name)
    # validate branch name
    error(isfeatureNameValid(name), "Feature name is invalid (#{name}), it should not start with #{FEATURE_COMMIT_PREFIX}")
    # create the new branch with an appropriate name
    error(system("git checkout -b #{generateFullFeatureBranchName(name)}"), 'Failed to create branch')
  end

  # ensure that we are on reference branch NOTE: should we try to checkout reference branch?
  error(CURRENT_BRANCH == REFERENCE_BRANCH_NAME, "Feature must branch from #{REFERENCE_BRANCH_NAME} (currently #{CURRENT_BRANCH})")
  # check if working directory clean
  error(isWorkingDirectoryClean, 'Working directory is not clean')
  # fetching changes
  error(system('git fetch'), 'Error fetching from origin')

  branches = `git for-each-ref --format='%(refname)' refs/heads/`.to_s.split("\n")
  featureBranches = branches.select{|branchName| branchName.start_with?('refs/heads/feature-')}
  featureBranches.collect! {|fullName| fullName['refs/heads/'.length..-1]}
  featureBranches.insert(0, 'créer une nouvelle feature')
  featureBranches.each_with_index do |featureBranchName, index|
    puts(index.to_s + ' ' + featureBranchName)
  end

  puts 'choix?'

  choice = gets.strip
  error(choice.is_positive_integer?, 'Veuillez rentrer un nombre entier')

  choice_i = choice.to_i
  error((0..featureBranches.length-1).cover?(choice_i) , 'Choix non valide')

  if choice_i == 0
    # créer nouvelle feature
    puts 'Quel est le nom de la nouvelle feature?'
    name = gets.strip
    createNewFeature name

    success "Feature #{generateFullFeatureBranchName(name)} successfully created"
  else
    # basculer sur la feature existante
    error(system("git checkout #{featureBranches[choice_i]}"), "Failed to switch to feature #{featureBranches[choice_i]}")

    success "Switched to feature #{featureBranches[choice_i]}"
  end
end

def optionCommit(message)
  # check if current branch is a feature
  error(isCurrentBranchFeature, 'You cannot commit from something else than a feature branch')
  # check if directory is not clean
  error(!isWorkingDirectoryClean, 'Working directory is clean')
  # add all and commit
  system 'git add -A'
  error(system("git commit -m \"#{generateFullCommitMessage(CURRENT_BRANCH, message)}\""), 'Failed to commit')

  success "Changes successfully commited"
end

def optionVersion
  # ensure being in reference branch
  error(isCurrentBranchReferenceBranch, 'You are not in the reference branch')
  # check if working directory clean
  error(isWorkingDirectoryClean, 'Working directory is not clean')
  # test again your modifications with the changes of the master branch
  error(system('git fetch'), 'Error fetching from origin')
  error(system("git merge master"), 'Error merging')
  error(system(TESTS_COMMAND), 'The tests are not passing, please fix and try again')
  # apply your modifications and go back to dev
  error(system("git checkout master"), "Failed to checkout master")
  error(system("git merge #{REFERENCE_BRANCH_NAME}"), "Failed to merge your work on master")
  error(system("git push"), "Failed to push the changes")
  error(system("git checkout #{REFERENCE_BRANCH_NAME}"), "Failed to checkout #{REFERENCE_BRANCH_NAME}")

  success "Successfully updated master"
end

def optionReference
  # ensure being in a branch feature
  error(isCurrentBranchFeature, 'You are not in a feature branch')
  # add all changes
  system 'git add -A'
  # check if directory is clean
  error(isWorkingDirectoryClean, 'Working directory is not clean, please stash or commit')
  # move to reference branch
  error(system("git checkout #{REFERENCE_BRANCH_NAME}"), "Failed to checkout reference branch (#{REFERENCE_BRANCH_NAME})")
  # pull latest changes
  error(system('git fetch'), 'Failed to fetch changes')

  success "Back to reference branch"
end

def optionHelp(options)
  puts options
end

#-------------- END OPTIONS LOGIC ----------------
optionParser = OptionParser.new do|options|

  options.on('-p', '--prune', 'Try to merge and push the current branch into the reference branch (! the feature branch get deleted after this operation)') do# check if working directory clean
    optionPrune
    exit
  end

  options.on('-u', '--update', 'Update feature with latest changes from the reference branche') do
    optionUpdate
    exit
  end

  options.on('-f', '--feature', 'Start developping a new or existing feature' ) do
    optionFeature
    exit
  end

  options.on('-c', '--commit MESSAGE', 'Stag and commit all changes to your current feature branch' ) do |message|
    optionCommit message
    exit
  end

  options.on('-r', '--reference', 'go back to reference branch') do
    optionReference
    exit
  end

  options.on('-v', '--version', 'publish reference branch to master') do
    optionVersion
    exit
  end

  options.on_tail( '-h', '--help', 'Display this screen' ) do
    optionHelp options
    exit
  end
end

optionParser.parse!