class ChefCLI::PolicyfileServices::Install

def expanded_run_list
  policyfile_compiler.expanded_run_list.to_s
end

def generate_lock_and_install
  policyfile_compiler.error!
  ui.msg "Building policy #{policyfile_compiler.name}"
  ui.msg "Expanded run list: " + expanded_run_list + "\n"
  ui.msg "Caching Cookbooks..."
  policyfile_compiler.install
  lock_data = policyfile_compiler.lock.to_lock
  with_file(policyfile_lock_expanded_path) do |f|
    f.print(FFI_Yajl::Encoder.encode(lock_data, pretty: true ))
  end
  ui.msg ""
  ui.msg "Lockfile written to #{policyfile_lock_expanded_path}"
  ui.msg "Policy revision id: #{policyfile_lock.revision_id}"
rescue => error
  raise PolicyfileInstallError.new("Failed to generate Policyfile.lock", error)
end

def initialize(policyfile: nil, ui: nil, root_dir: nil, overwrite: false, config: nil)
  @ui = ui
  @overwrite = overwrite
  @chef_config = config
  policyfile_rel_path = policyfile || "Policyfile.rb"
  policyfile_full_path = File.expand_path(policyfile_rel_path, root_dir)
  @storage_config = Policyfile::StorageConfig.new.use_policyfile(policyfile_full_path)
  @policyfile_content = nil
  @policyfile_compiler = nil
end

def install_from_lock
  ui.msg "Installing cookbooks from lock"
  policyfile_lock.install_cookbooks
rescue => error
  raise PolicyfileInstallError.new("Failed to install cookbooks from lockfile", error)
end

def installing_from_lock?
  !@overwrite && File.exist?(policyfile_lock_expanded_path)
end

def policyfile_compiler
  @policyfile_compiler ||= ChefCLI::PolicyfileCompiler.evaluate(policyfile_content, policyfile_expanded_path, ui: ui, chef_config: chef_config)
end

def policyfile_content
  @policyfile_content ||= IO.read(policyfile_expanded_path)
end

def policyfile_lock
  return nil if policyfile_lock_content.nil?
  @policyfile_lock ||= begin
    lock_data = FFI_Yajl::Parser.new.parse(policyfile_lock_content)
    PolicyfileLock.new(storage_config, ui: ui).build_from_lock_data(lock_data)
  end
end

def policyfile_lock_content
  @policyfile_lock_content ||= IO.read(policyfile_lock_expanded_path) if File.exist?(policyfile_lock_expanded_path)
end

def prepare_constraints_for_policies
  Policyfile::LockApplier
    .new(policyfile_lock, policyfile_compiler)
    .apply!
end

def prepare_constraints_for_update(to_update)
  ui.msg "Will relax constraints on:"
  to_update.each do |ck|
    ui.msg " - #{ck}"
  end
  policyfile_lock.cookbook_locks.each do |ck_name, location_spec|
    next if to_update.include?(ck_name)
    # we need to feed policyfile_compiler.cookbook_location_spec_for with a CookbookLocationSpecification
    policyfile_compiler.dsl.cookbook_location_specs[ck_name] = Policyfile::CookbookLocationSpecification.new(
      ck_name,
      Semverse::Constraint.new("=#{location_spec.version}"),
      location_spec.source_options,
      location_spec.storage_config
    )
  end
end

def run(cookbooks_to_update = [], exclude_deps = false)
  unless File.exist?(policyfile_expanded_path)
    # TODO: suggest next step. Add a generator/init command? Specify path to Policyfile.rb?
    # See card CC-232
    raise PolicyfileNotFound, "Policyfile not found at path #{policyfile_expanded_path}"
  end
  if installing_from_lock?
    install_from_lock
  elsif cookbooks_to_update.empty? # means update everything
    generate_lock_and_install
  else
    update_lock_and_install(cookbooks_to_update, exclude_deps)
  end
end

def update_lock_and_install(cookbooks_to_update, exclude_deps)
  ui.msg "Updating #{cookbooks_to_update.join(",")} cookbooks #{exclude_deps ? "(excluding dependencies)" : ""}"
  to_update = if exclude_deps
                cookbooks_to_update
              else
                policyfile_lock.solution_dependencies.transitive_deps(cookbooks_to_update)
              end
  prepare_constraints_for_update(to_update)
  prepare_constraints_for_policies
  generate_lock_and_install
end