# coding: utf-8

require 'fig/not_yet_parsed_package'
require 'fig/package_descriptor'
require 'fig/parser'

module Fig; end
class Fig::Command; end

# Loads the base package.
class Fig::Command::PackageLoader
  attr_reader :package_loaded_from_path

  DEFAULT_PACKAGE_FILE = 'package.fig'
  DEFAULT_APPLICATION_FILE = 'application.fig'

  def initialize(
    application_configuration,
    descriptor,
    package_definition_file,
    base_config,
    repository
  )
    @application_configuration    = application_configuration
    @descriptor                   = descriptor
    @package_definition_file      = package_definition_file
    @base_config                  = base_config
    @repository                   = repository
  end

  def load_package_object_from_file()
    definition_text = load_package_definition_file_contents()

    parse_package_definition_file(definition_text)

    return @base_package
  end

  def load_package_object()
    if @descriptor.nil?
      load_package_object_from_file()
    else
      set_base_package @repository.get_package(@descriptor)
    end

    return @base_package
  end

  def package_source_description()
    if @package_loaded_from_path
      return @package_loaded_from_path
    elsif @descriptor
      return Fig::PackageDescriptor.format(
        @descriptor.name, @descriptor.version, nil
      )
    end

    return nil
  end

  private

  def load_package_definition_file_contents()
    if @package_definition_file == :none
      return nil
    elsif @package_definition_file == '-'
      @package_loaded_from_path = '<standard input>'

      return $stdin.read
    elsif @package_definition_file.nil?
      if File.exist?(DEFAULT_PACKAGE_FILE)
        @package_loaded_from_path = DEFAULT_PACKAGE_FILE
      elsif File.exist?(DEFAULT_APPLICATION_FILE)
        @package_loaded_from_path = DEFAULT_APPLICATION_FILE
      end

      if @package_loaded_from_path
        return File.read(@package_loaded_from_path)
      end
    else
      return read_in_package_definition_file(@package_definition_file)
    end

    return
  end

  def read_in_package_definition_file(config_file)
    if File.exist?(config_file)
      @package_loaded_from_path = config_file
      @package_include_file_base_directory = File.dirname config_file

      return File.read(config_file)
    else
      raise Fig::UserInputError.new(%Q<File "#{config_file}" does not exist.>)
    end
  end

  def parse_package_definition_file(definition_text)
    if definition_text.nil?
      # This package gets a free ride in terms of requiring a base config; we
      # synthesize it.
      set_base_package_to_empty_synthetic_one()
      return
    end

    source_description = package_source_description()

    descriptor = Fig::PackageDescriptor.new(
      nil,
      nil,
      nil,
      :description => source_description,
      :source_description => source_description
    )

    unparsed_package = Fig::NotYetParsedPackage.new
    unparsed_package.descriptor                   = descriptor
    unparsed_package.working_directory            = '.'
    unparsed_package.include_file_base_directory  =
      @package_include_file_base_directory || '.'
    unparsed_package.source_description           = source_description
    unparsed_package.unparsed_text                = definition_text

    set_base_package(
      Fig::Parser.new(
        @application_configuration, :check_include_versions
      ).parse_package(unparsed_package)
    )

    return
  end

  def set_base_package_to_empty_synthetic_one()
    set_base_package(
      Fig::Package.new(
        nil,  # Name
        nil,  # Version
        'synthetic',
        '.',  # Working
        '.',  # Base
        [
          Fig::Statement::Configuration.new(
            nil,
            %Q<[synthetic statement created in #{__FILE__} line #{__LINE__}]>,
            @base_config,
            []
          )
        ],
        :is_synthetic,
      )
    )

    return
  end

  def set_base_package(package)
    @base_package = package
    package.set_base true

    return
  end
end