require 'fig/logging'
require 'fig/notfounderror'
require 'fig/package/archive'
require 'fig/package/resource'
require 'fig/parser'
require 'fig/repositoryerror'
require 'fig/urlaccesserror'

module Fig
  # Overall management of a repository.  Handles local operations itself;
  # defers remote operations to others.
  class Repository
    def self.is_url?(url)
      not (/ftp:\/\/|http:\/\/|file:\/\/|ssh:\/\// =~ url).nil?
    end

    def initialize(os, local_repository_dir, remote_repository_url, application_config, remote_repository_user=nil, update=false, update_if_missing=true)
      @os = os
      @local_repository_dir = local_repository_dir
      @remote_repository_url = remote_repository_url
      @remote_repository_user = remote_repository_user
      @application_config = application_config
      @update = update
      @update_if_missing = update_if_missing
      @parser = Parser.new(@application_config)

      @overrides = {}
      if File.exist?('fig.properties')
        File.readlines('fig.properties').each do |line|
          descriptor, path = line.strip.split('=')
          @overrides[descriptor] = path
        end
      end
    end

    def clean(package_name, version_name)
      dir = File.join(@local_repository_dir, package_name)
      dir = File.join(dir, version_name) if version_name
      FileUtils.rm_rf(dir)
    end

    def list_packages
      results = []
      if File.exist?(@local_repository_dir)
        @os.list(@local_repository_dir).each do |package_name|
          @os.list(File.join(@local_repository_dir, package_name)).each do |version_name|
            results << "#{package_name}/#{version_name}"
          end
        end
      end
      results
    end

    def list_remote_packages
      @os.download_list(@remote_repository_url)
    end

    def publish_package(package_statements, package_name, version_name, local_only)
      temp_dir = temp_dir_for_package(package_name, version_name)
      @os.clear_directory(temp_dir)
      local_dir = local_dir_for_package(package_name, version_name)
      @os.clear_directory(local_dir)
      fig_file = File.join(temp_dir, '.fig')
      content = bundle_resources(package_statements).map do |statement|
        if statement.is_a?(Package::Publish)
          nil
        elsif statement.is_a?(Package::Archive) || statement.is_a?(Package::Resource)
          if statement.is_a?(Package::Resource) && !Repository.is_url?(statement.url)
            archive_name = statement.url
            archive_remote = "#{remote_dir_for_package(package_name, version_name)}/#{statement.url}"
          else
            archive_name = statement.url.split('/').last
            archive_remote = "#{remote_dir_for_package(package_name, version_name)}/#{archive_name}"
          end
          if Repository.is_url?(statement.url)
            archive_local = File.join(temp_dir, archive_name)
            @os.download(statement.url, archive_local)
          else
            archive_local = statement.url
          end
          @os.upload(archive_local, archive_remote, @remote_repository_user) unless local_only
          @os.copy(archive_local, local_dir + '/' + archive_name)
          if statement.is_a?(Package::Archive)
            @os.unpack_archive(local_dir, archive_name)
          end
          statement.class.new(archive_name).unparse('')
        else
          statement.unparse('')
        end
      end.select {|s|not s.nil?}
      @os.write(fig_file, content.join("\n").strip)
      @os.upload(fig_file, remote_fig_file_for_package(package_name, version_name), @remote_repository_user) unless local_only
      @os.copy(fig_file, local_fig_file_for_package(package_name, version_name))
    end

    def bundle_resources(package_statements)
      resources = []
      new_package_statements = package_statements.reject do |statement|
        if statement.is_a?(Package::Resource) && !Repository.is_url?(statement.url)
          resources << statement.url
          true
        else
          false
        end
      end
      if resources.size > 0
        resources = expand_globs_from(resources)
        file = 'resources.tar.gz'
        @os.create_archive(file, resources)
        new_package_statements.unshift(Package::Archive.new(file))
        at_exit { File.delete(file) }
      end
      new_package_statements
    end

    def load_package(package_name, version_name)
      Logging.debug "Considering #{package_name}/#{version_name}."
      if @update || (@update_if_missing && package_missing?(package_name, version_name))
        update_package(package_name, version_name)
      end
      read_local_package(package_name, version_name)
    end

    def updating?
      return @update || @update_if_missing
    end

    def update_package(package_name, version_name)
      remote_fig_file = remote_fig_file_for_package(package_name, version_name)
      local_fig_file = local_fig_file_for_package(package_name, version_name)
      begin
        if @os.download(remote_fig_file, local_fig_file)
          install_package(package_name, version_name)
        end
      rescue NotFoundError
        Logging.fatal "Package not found in remote repository: #{package_name}/#{version_name}"
        delete_local_package(package_name, version_name)
        raise RepositoryError.new
      end
    end

    def read_local_package(package_name, version_name)
      dir = local_dir_for_package(package_name, version_name)
      read_package_from_directory(dir, package_name, version_name)
    end

    def read_package_from_directory(dir, package_name, version_name)
      file = File.join(dir, '.fig')
      if not File.exist?(file)
        file = File.join(dir, 'package.fig')
      end
      if not File.exist?(file)
        Logging.fatal "Fig file not found for package: #{file}"
        raise RepositoryError.new
      end
      read_package_from_file(file, package_name, version_name)
    end

    def read_package_from_file(file_name, package_name, version_name)
      if not File.exist?(file_name)
        Logging.fatal "Package not found: #{package_name}/#{version_name}"
        raise RepositoryError.new
      end
      content = File.read(file_name)
      return @parser.parse_package(package_name, version_name, File.dirname(file_name), content)
    end

    def local_dir_for_package(package_name, version_name)
      descriptor = "#{package_name}/#{version_name}"
      dir = @overrides[descriptor]
      if dir
        Logging.info "override: #{descriptor}=#{dir}"
      else
        dir = File.join(@local_repository_dir, package_name, version_name)
      end
      dir
    end

  private

    def install_package(package_name, version_name)
      begin
        package = read_local_package(package_name, version_name)
        temp_dir = temp_dir_for_package(package_name, version_name)
        @os.clear_directory(temp_dir)
        package.archive_urls.each do |archive_url|
          if not Repository.is_url?(archive_url)
            archive_url = remote_dir_for_package(package_name, version_name) + '/' + archive_url
          end
          @os.download_archive(archive_url, File.join(temp_dir))
        end
        package.resource_urls.each do |resource_url|
          if not Repository.is_url?(resource_url)
            resource_url = remote_dir_for_package(package_name, version_name) + '/' + resource_url
          end
          @os.download_resource(resource_url, File.join(temp_dir))
        end
        local_dir = local_dir_for_package(package_name, version_name)
        @os.clear_directory(local_dir)
        # some packages contain no files, only a fig file.
        if not (package.archive_urls.empty? && package.resource_urls.empty?)
          FileUtils.mv(Dir.glob(File.join(temp_dir, '*')), local_dir)
        end
        write_local_package(package_name, version_name, package)
      rescue
        Logging.fatal 'Install failed, cleaning up.'
        delete_local_package(package_name, version_name)
        raise RepositoryError.new
      end
    end

    # 'resources' is an Array of filenames: ['tmp/foo/file1', 'tmp/foo/*.jar']
    def expand_globs_from(resources)
      expanded_files = []
      resources.each {|f| expanded_files.concat(Dir.glob(f))}
      expanded_files
    end

    def delete_local_package(package_name, version_name)
      FileUtils.rm_rf(local_dir_for_package(package_name, version_name))
    end

    def write_local_package(package_name, version_name, package)
      file = local_fig_file_for_package(package_name, version_name)
      @os.write(file, package.unparse)
    end

    def remote_fig_file_for_package(package_name, version_name)
      "#{@remote_repository_url}/#{package_name}/#{version_name}/.fig"
    end

    def local_fig_file_for_package(package_name, version_name)
      File.join(local_dir_for_package(package_name, version_name), '.fig')
    end

    def remote_dir_for_package(package_name, version_name)
      "#{@remote_repository_url}/#{package_name}/#{version_name}"
    end

    def temp_dir_for_package(package_name, version_name)
      File.join(@local_repository_dir, 'tmp')
    end

    def package_missing?(package_name, version_name)
      not File.exist?(local_fig_file_for_package(package_name, version_name))
    end
  end
end