require 'fileutils'
require_relative 'helper'

module Dply
  class CodeArchive

    include Helper

    attr_reader :name, :branch
    attr_writer :skip_depcheck

    def initialize(name, revision:)
      @name = name
      @branch = get_branch
      @revision = revision
      @dir = "#{Dir.pwd}/tmp/build_artifacts"
      @skip_depcheck = false
      validate
    end

    def build(empty: false, gnu_tar: false, &block)
      make_dir
      create_tar empty, gnu_tar
      instance_eval(&block) if block
      add_git_commit_id
      add_revision
      add_archive_name
    end

    def depcheck!
      return if @skip_depcheck
      command = %(ruby -W0 "#{__dir__}/scripts/depcheck.rb" #{tar})
      logger.bullet "depcheck #{tar}"
      env = logger.debug? ? { "LOG_DEBUG" => "true" } : {}
      cmd command, display: false, env: env
    end

    def compress!
      cmd %(#{gzip} -f -9 "#{tar}")
    end

    private

    def get_branch
      out = `git rev-parse --abbrev-ref HEAD`
      out.chomp.tr("/", "_")
    end

    def tar
      @tar ||= "#{@dir}/#{@name}-#{@revision}-#{@branch}.tar"
    end

    def make_dir
      FileUtils.mkdir @dir if not File.directory? @dir
    end

    def create_tar(empty, gnu_tar)
      tmp_dir = "tmp/app_code"
      return if empty
      if gnu_tar
        FileUtils.rm_rf tmp_dir
        FileUtils.mkdir tmp_dir
        sh "git archive HEAD | tar xf - -C #{tmp_dir}"
        cmd "tar cf #{tar} -C #{tmp_dir} ."
      else
        cmd "git archive -o #{tar} HEAD"
      end
    ensure
      FileUtils.rm_rf tmp_dir
    end

    def add(file, dereference: false)
      realpath = File.realpath(file)
      tar_relpath = Pathname.new(tar).relative_path_from(Pathname.new(Dir.pwd)).to_s
      command = ["tar", "--append", "-f", tar_relpath]
      command << "-h" if dereference
      if File.symlink?(file) && File.directory?(realpath)
        prefix = file.sub(":", '\:')
        command.concat ["-C", file, "--transform", "s:^./:#{prefix}/:S", "."]
      else
        command << file
      end
      cmd command
    end

    def remove(file)
      cmd %(tar --delete -f "#{tar}" "#{file}")
    end

    def add_git_commit_id
      commit_id = `git rev-parse HEAD`.chomp!
      file = "GIT_COMMIT_ID"
      File.write(file, commit_id)
      add file
    end

    def add_revision
      file = "REVISION"
      File.write(file, @revision)
      add file
    end

    def add_archive_name
      file = "ARCHIVE_NAME"
      File.write(file, @name)
      add file
    end

    def add_bundle
      add ".bundle"
      add "vendor/bundle"
    end

    def gzip
      File.exist?("/usr/bin/pigz") ? "pigz" : "gzip"
    end

    def validate
      [:name, :branch, :revision, :dir].each do |i|
        ivar = "@#{i}"
        v = instance_variable_get(ivar)
        raise Error, "archive param :#{i} is empty" if (!v || v.strip.empty?)
      end
    end
  end
end