class Paperclip::Attachment

def self.default_options
  @default_options ||= {
    :convert_options       => {},
    :default_style         => :original,
    :default_url           => "/:attachment/:style/missing.png",
    :escape_url            => true,
    :restricted_characters => /[&$+,\/:;=?@<>\[\]\{\}\|\\\^~%# ]/,
    :filename_cleaner      => nil,
    :hash_data             => ":class/:attachment/:id/:style/:updated_at",
    :hash_digest           => "SHA1",
    :interpolator          => Paperclip::Interpolations,
    :only_process          => [],
    :path                  => ":rails_root/public:url",
    :preserve_files        => false,
    :processors            => [:thumbnail],
    :source_file_options   => {},
    :storage               => :filesystem,
    :styles                => {},
    :url                   => "/system/:class/:attachment/:id_partition/:style/:filename",
    :url_generator         => Paperclip::UrlGenerator,
    :use_default_time_zone => true,
    :use_timestamp         => true,
    :whiny                 => Paperclip.options[:whiny] || Paperclip.options[:whiny_thumbnails],
    :validate_media_type   => true,
    :adapter_options       => { hash_digest: Digest::MD5 },
    :check_validity_before_processing => true
  }
end

def able_to_store_created_at?
  @instance.respond_to?("#{name}_created_at".to_sym)
end

def active_validator_classes
  @instance.class.validators.map(&:class)
end

def after_flush_writes
  unlink_files(@queued_for_write.values)
end

def as_json(options = nil)
  to_s((options && options[:style]) || default_style)
end

def assign(uploaded_file)
  @file = Paperclip.io_adapters.for(uploaded_file,
                                    @options[:adapter_options])
  ensure_required_accessors!
  ensure_required_validations!
  if @file.assignment?
    clear(*only_process)
    if @file.nil?
      nil
    else
      assign_attributes
      post_process_file
      reset_file_if_original_reprocessed
    end
  else
    nil
  end
end

def assign_attributes
  @queued_for_write[:original] = @file
  assign_file_information
  assign_fingerprint { @file.fingerprint }
  assign_timestamps
end

def assign_file_information
  instance_write(:file_name, cleanup_filename(@file.original_filename))
  instance_write(:content_type, @file.content_type.to_s.strip)
  instance_write(:file_size, @file.size)
end

def assign_fingerprint
  if instance_respond_to?(:fingerprint)
    instance_write(:fingerprint, yield)
  end
end

def assign_timestamps
  if has_enabled_but_unset_created_at?
    instance_write(:created_at, Time.now)
  end
  instance_write(:updated_at, Time.now)
end

def blank?
  not present?
end

def cleanup_filename(filename)
  filename_cleaner.call(filename)
end

def clear(*styles_to_clear)
  if styles_to_clear.any?
    queue_some_for_delete(*styles_to_clear)
  else
    queue_all_for_delete
    @queued_for_write  = {}
    @errors            = {}
  end
end

def content_type
  instance_read(:content_type)
end

def created_at
  if able_to_store_created_at?
    time = instance_read(:created_at)
    time && time.to_f.to_i
  end
end

def default_options
  {
    :timestamp => @options[:use_timestamp],
    :escape => @options[:escape_url]
  }
end

def default_style
  @options[:default_style]
end

def destroy
  clear
  save
end

def dirty!
  @dirty = true
end

def dirty?
  @dirty
end

def ensure_required_accessors! #:nodoc:
  %w(file_name).each do |field|
    unless @instance.respond_to?("#{@name_string}_#{field}") && @instance.respond_to?("#{@name_string}_#{field}=")
      raise Paperclip::Error.new("#{@instance.class} model missing required attr_accessor for '#{@name_string}_#{field}'")
    end
  end
end

def ensure_required_validations!
  if missing_required_validator?
    raise Paperclip::Errors::MissingRequiredValidatorError
  end
end

def errors
  @errors
end

def expiring_url(time = 3600, style_name = default_style)
  url(style_name)
end

def extra_options_for(style) #:nodoc:
  process_options(:convert_options, style)
end

def extra_source_file_options_for(style) #:nodoc:
  process_options(:source_file_options, style)
end

def file?
  original_filename.present?
end

def filename_cleaner
  @options[:filename_cleaner] || FilenameCleaner.new(@options[:restricted_characters])
end

def fingerprint
  instance_read(:fingerprint)
end

def flush_errors #:nodoc:
  @errors.each do |error, message|
    [message].flatten.each {|m| instance.errors.add(name, m) }
  end
end

def has_enabled_but_unset_created_at?
  able_to_store_created_at? && !instance_read(:created_at)
end

def hash_key(style_name = default_style)
  raise ArgumentError, "Unable to generate hash without :hash_secret" unless @options[:hash_secret]
  require 'openssl' unless defined?(OpenSSL)
  data = interpolate(@options[:hash_data], style_name)
  OpenSSL::HMAC.hexdigest(OpenSSL::Digest.const_get(@options[:hash_digest]).new, @options[:hash_secret], data)
end

def initialize(name, instance, options = {})
  @name              = name.to_sym
  @name_string       = name.to_s
  @instance          = instance
  options = self.class.default_options.deep_merge(options)
  @options               = options
  @post_processing       = true
  @queued_for_delete     = []
  @queued_for_write      = {}
  @errors                = {}
  @dirty                 = false
  @interpolator          = options[:interpolator]
  @url_generator         = options[:url_generator].new(self)
  @source_file_options   = options[:source_file_options]
  @whiny                 = options[:whiny]
  initialize_storage
end

def initialize_storage #:nodoc:
  storage_class_name = @options[:storage].to_s.downcase.camelize
  begin
    storage_module = Paperclip::Storage.const_get(storage_class_name)
  rescue NameError
    raise Errors::StorageMethodNotFound, "Cannot load storage module '#{storage_class_name}'"
  end
  self.extend(storage_module)
end

def instance_read(attr)
  getter = :"#{@name_string}_#{attr}"
  if instance.respond_to?(getter)
    instance.send(getter)
  end
end

def instance_respond_to?(attr)
  instance.respond_to?(:"#{name}_#{attr}")
end

def instance_write(attr, value)
  setter = :"#{@name_string}_#{attr}="
  if instance.respond_to?(setter)
    instance.send(setter, value)
  end
end

def interpolate(pattern, style_name = default_style) #:nodoc:
  interpolator.interpolate(pattern, self, style_name)
end

def log message #:nodoc:
  Paperclip.log(message)
end

def missing_required_validator?
  (active_validator_classes.flat_map(&:ancestors) & Paperclip::REQUIRED_VALIDATORS).empty?
end

def only_process
  only_process = @options[:only_process].dup
  only_process = only_process.call(self) if only_process.respond_to?(:call)
  only_process.map(&:to_sym)
end

def original_filename
  instance_read(:file_name)
end

def path(style_name = default_style)
  path = original_filename.nil? ? nil : interpolate(path_option, style_name)
  path.respond_to?(:unescape) ? path.unescape : path
end

def path_option
  @options[:path].respond_to?(:call) ? @options[:path].call(self) : @options[:path]
end

def post_process(*style_args) #:nodoc:
  return if @queued_for_write[:original].nil?
  instance.run_paperclip_callbacks(:post_process) do
    instance.run_paperclip_callbacks(:"#{name}_post_process") do
      if !@options[:check_validity_before_processing] || !instance.errors.any?
        post_process_styles(*style_args)
      end
    end
  end
end

def post_process_file
  dirty!
  if post_processing
    post_process(*only_process)
  end
end

def post_process_style(name, style) #:nodoc:
  begin
    raise RuntimeError.new("Style #{name} has no processors defined.") if style.processors.blank?
    intermediate_files = []
    original = @queued_for_write[:original]
    @queued_for_write[name] = style.processors.
      reduce(original) do |file, processor|
      file = Paperclip.processor(processor).make(file, style.processor_options, self)
      intermediate_files << file unless file == @queued_for_write[:original]
      # if we're processing the original, close + unlink the source tempfile
      if name == :original
        @queued_for_write[:original].close(true)
      end
      file
    end
    unadapted_file = @queued_for_write[name]
    @queued_for_write[name] = Paperclip.io_adapters.
      for(@queued_for_write[name], @options[:adapter_options])
    unadapted_file.close if unadapted_file.respond_to?(:close)
    @queued_for_write[name]
  rescue Paperclip::Errors::NotIdentifiedByImageMagickError => e
    log("An error was received while processing: #{e.inspect}")
    (@errors[:processing] ||= []) << e.message if @options[:whiny]
  ensure
    unlink_files(intermediate_files)
  end
end

def post_process_styles(*style_args) #:nodoc:
  post_process_style(:original, styles[:original]) if styles.include?(:original) && process_style?(:original, style_args)
  styles.reject{ |name, style| name == :original }.each do |name, style|
    post_process_style(name, style) if process_style?(name, style_args)
  end
end

def process_options(options_type, style) #:nodoc:
  all_options   = @options[options_type][:all]
  all_options   = all_options.call(instance)   if all_options.respond_to?(:call)
  style_options = @options[options_type][style]
  style_options = style_options.call(instance) if style_options.respond_to?(:call)
  [ style_options, all_options ].compact.join(" ")
end

def process_style?(style_name, style_args) #:nodoc:
  style_args.empty? || style_args.include?(style_name)
end

def processors
  processing_option = @options[:processors]
  if processing_option.respond_to?(:call)
    processing_option.call(instance)
  else
    processing_option
  end
end

def queue_all_for_delete #:nodoc:
  return if !file?
  unless @options[:preserve_files]
    @queued_for_delete += [:original, *styles.keys].uniq.map do |style|
      path(style) if exists?(style)
    end.compact
  end
  instance_write(:file_name, nil)
  instance_write(:content_type, nil)
  instance_write(:file_size, nil)
  instance_write(:fingerprint, nil)
  instance_write(:created_at, nil) if has_enabled_but_unset_created_at?
  instance_write(:updated_at, nil)
end

def queue_some_for_delete(*styles)
  @queued_for_delete += styles.uniq.map do |style|
    path(style) if exists?(style)
  end.compact
end

def reprocess!(*style_args)
  saved_flags = @options.slice(
    :only_process,
    :preserve_files,
    :check_validity_before_processing
  )
  @options[:only_process] = style_args
  @options[:preserve_files] = true
  @options[:check_validity_before_processing] = false
  begin
    assign(self)
    save
    instance.save
  rescue Errno::EACCES => e
    warn "#{e} - skipping file."
    false
  ensure
    @options.merge!(saved_flags)
  end
end

def reset_file_if_original_reprocessed
  instance_write(:file_size, @queued_for_write[:original].size)
  assign_fingerprint { @queued_for_write[:original].fingerprint }
  reset_updater
end

def reset_updater
  if instance.respond_to?(updater)
    instance.send(updater)
  end
end

def save
  flush_deletes unless @options[:keep_old_files]
  process = only_process
  if process.any? && !process.include?(:original)
    @queued_for_write.except!(:original)
  end
  flush_writes
  @dirty = false
  true
end

def size
  instance_read(:file_size) || (@queued_for_write[:original] && @queued_for_write[:original].size)
end

def staged?
  ! @queued_for_write.empty?
end

def staged_path(style_name = default_style)
  if staged?
    @queued_for_write[style_name].path
  end
end

def styles
  if @options[:styles].respond_to?(:call) || @normalized_styles.nil?
    styles = @options[:styles]
    styles = styles.call(self) if styles.respond_to?(:call)
    @normalized_styles = styles.dup
    styles.each_pair do |name, options|
      @normalized_styles[name.to_sym] = Paperclip::Style.new(name.to_sym, options.dup, self)
    end
  end
  @normalized_styles
end

def time_zone
  @options[:use_default_time_zone] ? Time.zone_default : Time.zone
end

def to_s style_name = default_style
  url(style_name)
end

def unlink_files(files)
  Array(files).each do |file|
    file.close unless file.closed?
    begin
      file.unlink if file.respond_to?(:unlink)
    rescue Errno::ENOENT
    end
  end
end

def updated_at
  time = instance_read(:updated_at)
  time && time.to_f.to_i
end

def updater
  :"#{name}_file_name_will_change!"
end

def uploaded_file
  instance_read(:uploaded_file)
end

def url(style_name = default_style, options = {})
  if options == true || options == false # Backwards compatibility.
    @url_generator.for(style_name, default_options.merge(:timestamp => options))
  else
    @url_generator.for(style_name, default_options.merge(options))
  end
end