require 'rakelib/hglib'

module Rake

end

module Rake::StX

end

# Cross-platform way of finding an executable in the $PATH.

#

#   which('ruby') #=> /usr/bin/ruby

def which(cmd)

  exts = ENV['PATHEXT'] ? ENV['PATHEXT'].split(';') : ['']

  ENV['PATH'].split(File::PATH_SEPARATOR).each do |path|

    exts.each { |ext|

      exe = File.join(path, "#{cmd}#{ext}")

      return exe if File.executable?(exe) && !File.directory?(exe)

    }

  end

  return nil

end

cvs_rsh_set = false

module Rake::Stx::SCM

  # Not quite sure why following code

  #

  #     include RakeFileUtils

  #

  # does not make extra methods (like `sh`) defined in `extensions.rb`

  # visible here. To workaround, define them here. Ugly...

  module_function

  def sh(cmd, cwd: Dir.pwd, &block)

    begin 

      return RakeFileUtils::sh(cmd, cwd: cwd, &block)

    rescue

      return false      

    end

  end

  # Make sure CVS_RSH environment variable is properly set. Prefer MSYS2 ssh.exe

  # over plink.exe. For details, see `hglib.rb`, method `sshconf()`  

  module_function

  def ensure_cvs_rsh_set()        

    if @cvs_rsh_set then

      return

    end

    ssh = nil

    ssh_configured = ENV['CVS_RSH']    

    ssh_in_path = which('ssh') ? true : false

    plink_in_path = which('plink') ? true : false

    if Gem.win_platform? then                        

      # If CVS_RSH is not set or is set to plink.exe, try to change to 

      # MSYS2 ssh.exe as it gives better performance on (fast) LANs.      

      if /^.*[pP]link(\.exe)?"?\s*(-ssh)?\s*(-2)?$/ =~ ssh_configured then            

        if ssh_in_path then

          ssh = 'ssh'

        else 

          if (File.exist? "c:\\msys64\\usr\\bin\\ssh.exe") then              

            ssh = "\"c:\\msys64\\usr\\bin\\ssh.exe\""

          end

        end

        # Sigh, we should not tamper with SSH configuration wildly. User may have

        # her ssh and mercurial properly configured to use `plink.exe` and `pageant`.

        # If we just start using `ssh.exe` clone/pull might not work beause

        # `ssh.exe` cannot talk to `pageant`. So, if we don't find OpenSSH's 

        # style of agent, don't use `ssh.exe` event if available.

        if ssh then

          if ENV['SSH_AUTH_SOCK'] then

            # Good, OpenSSH agent running but still, be nice and  tell the 

            # user SSH configuration has been tampered wirh. 

            info("Setting CVS_RSH=\"#{ssh}\" for faster transfers")

          else 

            # No agent, no fun. Be nice and give user a hit

            warn("Not using CVS_RSH=\"#{ssh}\" option because SSH agent is not running")

            warn("For faster CVS checkout over LAN, consider using ssh-agent or ssh-pageant (if you want to use PuTTY's pageant)")

            ssh = nil

          end

        end

      end       

    else                 

      if not ssh_configured then

        ssh = "ssh"

      end

    end

    if ssh then 

      ENV['CVS_RSH'] = ssh

    end

    cvs_rsh_set = true

  end

  public

  class CheckoutException < Exception

  end # class CheckoutException

  def self._check_type(type)

    if (type != :cvs and type != :svn and type != :git and type != :hg)

      raise CheckoutException.new("Unknown version control system type (#{type})")

    end

  end

  def self.update(repository, directory, **kwargs)

    type = repository.type

    url = repository.canonical

    self._check_type(type)    

    root = kwargs[:root] || BUILD_DIR

    branch = kwargs[:branch]

    if branch == nil

      if type == :svn

        branch = 'trunk'

      elsif type == :hg

        branch = 'default'

      end

    end

    wc = root / directory

    if (! File.exist? wc)

      self.checkout(repository, directory, **kwargs)

      return

    end

    case type

      when :svn    then _update_svn(repository, directory, branch, root, **kwargs)

      when :cvs    then _update_cvs(repository, directory, branch, root, **kwargs)

      when :git    then _update_git(repository, directory, branch, root, **kwargs)

      when :hg     then _update_hg(repository, directory, branch, root, **kwargs)

    end

  end

  def self._update_hg(repository, directory, branch, root, **kwargs)

    wc = root / directory

    separator = kwargs[:separator] || '.'

    revision =  kwargs[:revision] 

    if directory != nil then      

      url = "#{repository.canonical}/#{directory.gsub('/', separator)}"

    end

    hg = HG::Repository.new(wc)

    begin

      paths = hg.paths

      if repository.staging then

        if not paths.has_key? 'staging'           

          paths['staging'] = "#{repository.staging}/#{directory.gsub('/', separator)}"

          hg.paths = paths

        end

        hg.pull('staging')

      end

      if repository.upstream then        

        if not paths.has_key? 'upstream'           

          paths['upstream'] = "#{repository.upstream}/#{directory.gsub('/', separator)}"

          hg.paths = paths

        end

        hg.pull('upstream')

      end

      if not paths.has_key? 'canonical'

        paths['canonical'] = "#{repository.canonical}/#{directory.gsub('/', separator)}"

        hg.paths = paths

      end

      # If revision is not specified, then look for an active bookmark

      # and update to it. If no bookmark is active, then look for bookmark

      # `master`. If it exist, then update to `master`. If it 

      # does not, then update to tip or throw an error.

      # The error is thrown if there's no bookmark `master` and

      # branch has multiple heads since it's not clear which 

      # head rev to use.

      if not revision then

        revision = hg.bookmark()

        if not revision then

          bookmarks = hg.bookmarks(branch)

          if (bookmarks.has_key? 'master') then

            revision = 'master'

          else

            if (hg.heads(branch).size > 1) then

              raise CheckoutException.new("HG: Cannot checkout #{directory}: branch #{branch} has multiple heads but no bookmark named 'master'!")

            end            

          end          

        end

      end

      hg.update(revision || branch)

    rescue Exception => ex 

      raise CheckoutException.new("HG: Cannot update #{wc}: #{ex.message}")

    end

  end

  def self._update_svn(repository, directory, branch, root, **kwargs)

    wc = root / directory

    if not sh %W{svn --non-interactive --trust-server-cert update}, cwd: wc

      raise CheckoutException.new("SVN: Cannot update #{wc}")

    end

  end

  def self._update_cvs(repository, directory, branch, root, **kwargs)

    ensure_cvs_rsh_set()

    wc = root / directory

    if File.directory? wc

      if not sh %W{cvs -z 9 update -A -d}, cwd: wc

        raise CheckoutException.new("CVS: Cannot update #{wc}")

      end

    else

      if not sh %W{cvs -z 9 update -A #{File.basename(wc)}}, cwd: File.dirname(wc)

        raise CheckoutException.new("CVS: Cannot update #{wc}")

      end

    end

  end

  def self.checkout(repository, directory, **kwargs)    

    type = repository.type

    url = repository.canonical

    self._check_type(type)

    root = kwargs[:root] || BUILD_DIR

    branch = kwargs[:branch]

    if branch == nil

      if type == :svn

        branch = 'trunk'

      elsif type == :hg

        branch = 'default'

      end

    end

    wc = root / directory

    if (File.exist? wc)

      self.update(repository, directory, **kwargs)

      return

    end

    if (not File.exists? File.dirname(wc))

      begin

        FileUtils.mkdir_p(File.dirname(wc))

      rescue => ex

        raise CheckoutException.new("Cannot create directory for working copy (#{ex})")

      end

    end

    case type

      when :svn    then _checkout_svn(repository, directory, branch, root, **kwargs)

      when :cvs    then _checkout_cvs(repository, directory, branch, root, **kwargs)

      when :git    then _checkout_git(repository, directory, branch, root, **kwargs)

      when :hg     then _checkout_hg(repository, directory, branch, root, **kwargs)      

    end

  end

  def self._checkout_svn(repository, directory, branch, root, **kwargs)    

    url = "#{repository.canonical}/#{directory}/#{branch}"

    if not sh %W{svn --non-interactive --trust-server-cert co #{url} #{directory}}, cwd: root

      raise CheckoutException.new("SVN: Cannot checkout from #{url}")

    end

  end

  def self._checkout_hg(repository, directory, branch, root, **kwargs)    

    separator = kwargs[:separator] || '.'

    revision =  kwargs[:revision] 

    if repository.upstream then

      paths['upstream'] = "#{repository.upstream}/#{directory.gsub('/', separator)}"

    end

    if repository.staging then

      paths['staging'] = "#{repository.staging}/#{directory.gsub('/', separator)}"

    end

    begin

      if repository.staging then

        paths['default'] = paths['staging']

        hg = HG::Repository.clone(paths['staging'], root / directory, noupdate: true)        

        hg.paths = paths

        hg.pull('upstream') if paths['upstream'] 

        hg.pull('canonical')

      elsif repository.upstream then

        paths['default'] = paths['upstream']

        hg = HG::Repository.clone(paths['upstream'], root / directory, noupdate: true)        

        hg.paths = paths

        hg.pull('canonical')

      else

        hg = HG::Repository.clone(paths['canonical'], root / directory, noupdate: true)

        hg.paths = paths

      end

      # If revision is not specified, then look for bookmark

      # `master`. If it exist, then check out `master`. If it 

      # does not, then checkout tip or throw an error.

      # The error is thrown if there's no bookmark `master` and

      # branch has multiple heads since it's not clear which 

      # head rev to use.

      if not revision then

        bookmarks = hg.bookmarks(branch)

        if (bookmarks.has_key? 'master') then

          revision = 'master'

        else

          if (hg.heads(branch).size > 1) then

            raise CheckoutException.new("HG: Cannot checkout #{directory}: branch #{branch} has multiple heads but no bookmark named 'master'!")

          end            

        end          

      end

      hg.update(revision || branch)

    #rescue Exception => e

    #  raise CheckoutException.new("HG: Cannot clone from #{url}: #{e.message}")

    end

  end

  def self._checkout_cvs(repository, directory, branch, root, **kwargs)    

    ensure_cvs_rsh_set()

    if not sh %W{cvs -z 9 -d #{repository.canonical} co #{directory}}, cwd: root

      raise CheckoutException.new("CVS: Cannot checkout #{directory}from #{repository.url}")

    end

  end

end # module Rake::Stx::SCM

def checkout(repo_name, directory, **kwargs)

  # repository should be symbolic name

  repo = Rake::Stx::Configuration::Repository::find(repo_name)

  if not repo then

      error("checkout(): No repository found (#{repo_name})")

  end  

  kwargs[:separator] = repo.separator

  Rake::Stx::SCM.checkout(repo, directory, **kwargs)  

end

def update(repo_name, directory, **kwargs)

  # repository should be symbolic name

  repo = Rake::Stx::Configuration::Repository::find(repo_name)

  if not repo then  

    error("update(): No repository found (#{repo_name})")

  end  

  kwargs[:separator] = repo.separator

  Rake::Stx::SCM.update(repo, directory, **kwargs)

end

def cvs(url, directory, **kwargs)

  repo = Rake::Stx::Configuration::Repository.new(:type => :cvs, :url => url)

  Rake::Stx::SCM.checkout(repo, directory, **kwargs)

end

def svn(url, directory, **kwargs)

  repo = Rake::Stx::Configuration::Repository.new(:type => :svn, :url => url)

  Rake::Stx::SCM.checkout(repo, directory, **kwargs)

end

def hg(url, directory, **kwargs)

  repo = Rake::Stx::Configuration::Repository.new(:type => :hg, :url => url)

  Rake::Stx::SCM.checkout(repo, directory, **kwargs)

end

def git(url, directory, **kwargs)

  repo = Rake::Stx::Configuration::Repository.new(:type => :git, :url => url)

  Rake::Stx::SCM.checkout(repo, directory, **kwargs)

end