#-- encoding: UTF-8
#-- copyright
# OpenProject is a project management system.
# Copyright (C) 2012-2013 the OpenProject Foundation (OPF)
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License version 3.
#
# OpenProject is a fork of ChiliProject, which is a fork of Redmine. The copyright follows:
# Copyright (C) 2006-2013 Jean-Philippe Lang
# Copyright (C) 2010-2013 the ChiliProject Team
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
# See doc/COPYRIGHT.rdoc for more details.
#++

require 'forwardable'
require 'cgi'

module ApplicationHelper
  include Redmine::WikiFormatting::Macros::Definitions
  include Redmine::I18n
  include ERB::Util # for h()

  extend Forwardable
  def_delegators :wiki_helper, :wikitoolbar_for, :heads_for_wiki_formatter

  # Return true if user is authorized for controller/action, otherwise false
  def authorize_for(controller, action)
    User.current.allowed_to?({:controller => controller, :action => action}, @project)
  end

  # Display a link if user is authorized
  #
  # @param [String] name Anchor text (passed to link_to)
  # @param [Hash] options Hash params. This will checked by authorize_for to see if the user is authorized
  # @param [optional, Hash] html_options Options passed to link_to
  # @param [optional, Hash] parameters_for_method_reference Extra parameters for link_to
  #
  # When a block is given, skip the name parameter
  def link_to_if_authorized(*args, &block)
    name = args.shift unless block_given?
    options = args.shift || {}
    html_options = args.shift
    parameters_for_method_reference = args

    return unless authorize_for(options[:controller] || params[:controller], options[:action])

    if block_given?
      link_to(options, html_options, *parameters_for_method_reference, &block)
    else
      link_to(name, options, html_options, *parameters_for_method_reference)
    end
  end

  def required_field_name(name = '')
    safe_join [name, ' ', content_tag('span', '*', class: 'required')]
  end

  def li_unless_nil(link)
    content_tag(:li, link) if link
  end

  # Display a link to remote if user is authorized
  def link_to_remote_if_authorized(name, options = {}, html_options = nil)
    url = options[:url] || {}
    link_to_remote(name, options, html_options) if authorize_for(url[:controller] || params[:controller], url[:action])
  end

  # Displays a link to user's account page if active or registered
  def link_to_user(user, options={})
    if user.is_a?(User)
      name = user.name(options.delete(:format))
      if user.active? || user.registered?
        link_to(name, user, options)
      else
        name
      end
    else
      h(user.to_s)
    end
  end

  def link_to_work_package_preview(context = nil, options = {})
    url = context.is_a?(Project) ?
            preview_project_work_packages_path(context) :
            preview_work_package_path(context)

    id = options[:form_id] || 'work_package-form-preview'

    link_to l(:label_preview),
              url,
              :id => id,
              :class => 'preview button',
              :accesskey => accesskey(:preview)

  end

  # Show a sorted linkified (if active) comma-joined list of users
  def list_users(users, options={})
    users.sort.collect{|u| link_to_user(u, options)}.join(", ")
  end

  #returns a class name based on the user's status
  def user_status_class(user)
    'status_' + user.status_name
  end

  def user_status_i18n(user)
    l(('status_' + user.status_name).to_sym)
  end

  # Generates a link to an attachment.
  # Options:
  # * :text - Link text (default to attachment filename)
  # * :download - Force download (default: false)
  def link_to_attachment(attachment, options={})
    text = options.delete(:text) || attachment.filename
    action = options.delete(:download) ? 'download' : 'show'
    only_path = options.delete(:only_path) { true }

    link_to h(text),
            {:controller => '/attachments',
             :action => action,
             :id => attachment,
             :filename => attachment.filename,
             :host => Setting.host_name,
             :protocol => Setting.protocol,
             :only_path => only_path },
            options
  end

  # Generates a link to a SCM revision
  # Options:
  # * :text - Link text (default to the formatted revision)
  def link_to_revision(revision, project, options={})
    text = options.delete(:text) || format_revision(revision)
    rev = revision.respond_to?(:identifier) ? revision.identifier : revision

    link_to(h(text), {:controller => '/repositories', :action => 'revision', :project_id => project, :rev => rev},
            :title => l(:label_revision_id, format_revision(revision)))
  end

  # Generates a link to a message
  def link_to_message(message, options={}, html_options = nil)
    link_to(
      h(truncate(message.subject, :length => 60)),
      { :controller => '/messages', :action => 'show',
        :board_id => message.board_id,
        :id => message.root,
        :r => (message.parent_id && message.id),
        :anchor => (message.parent_id ? "message-#{message.id}" : nil)
      }.merge(options),
      html_options
    )
  end

  # Generates a link to a project if active
  # Examples:
  #
  #   link_to_project(project)                          # => link to the specified project overview
  #   link_to_project(project, :action=>'settings')     # => link to project settings
  #   link_to_project(project, {:only_path => false}, :class => "project") # => 3rd arg adds html options
  #   link_to_project(project, {}, :class => "project") # => html options with default url (project overview)
  #
  def link_to_project(project, options={}, html_options = nil, show_icon = false)
    link = ''

    if show_icon && User.current.member_of?(project)
      link << icon_wrapper("icon-context icon-star1",I18n.t(:description_my_project))
    end

    if project.active?
      # backwards compatibility
      if options.delete(:action) == 'settings'
        link << link_to(project.name, settings_project_path(project, options), html_options)
      else
        link << link_to(project.name, project_path(project, options), html_options)
      end
    else
      link << project.name
    end

    link.html_safe
  end

  def toggle_link(name, id, options={})
    onclick = "Element.toggle('#{id}'); "
    onclick << (options[:focus] ? "Form.Element.focus('#{options[:focus]}'); " : "this.blur(); ")
    onclick << "return false;"
    link_to(name, "#", :onclick => onclick)
  end

  def delete_link(url, options={})
    options = {
      :method => :delete,
      :data => {:confirm => l(:text_are_you_sure)},
      :class => 'icon icon-delete'
    }.merge(options)

    link_to l(:button_delete), url, options
  end

  def image_to_function(name, function, html_options = {})
    html_options.symbolize_keys!
    tag(:input, html_options.merge({
        :type => "image", :src => image_path(name),
        :onclick => (html_options[:onclick] ? "#{html_options[:onclick]}; " : "") + "#{function};"
        }))
  end

  def prompt_to_remote(name, text, param, url, html_options = {})
    html_options[:onclick] = "promptToRemote('#{text}', '#{param}', '#{url_for(url)}'); return false;"
    link_to name, {}, html_options
  end

  def format_activity_title(text)
    h(truncate_single_line(text, :length => 100))
  end

  def format_activity_day(date)
    date == Date.today ? l(:label_today).titleize : format_date(date)
  end

  def format_activity_description(text)
    h(truncate(text.to_s, :length => 120).gsub(%r{[\r\n]*<(pre|code)>.*$}m, '...')).gsub(/[\r\n]+/, "<br />").html_safe
  end

  def format_version_name(version)
    if version.project == @project
    	h(version)
    else
      h("#{version.project} - #{version}")
    end
  end

  def due_date_distance_in_words(date)
    if date
      l((date < Date.today ? :label_roadmap_overdue : :label_roadmap_due_in), distance_of_date_in_words(Date.today, date))
    end
  end

  def render_page_hierarchy(pages, node=nil, options={})
    return '' unless pages[node]

    content_tag :ul, class: 'pages-hierarchy' do
      pages[node].collect do |page|
        content_tag :li do
          concat link_to(page.pretty_title, project_wiki_path(page.project, page),
            title: (options[:timestamp] && page.updated_on ? l(:label_updated_time, distance_of_time_in_words(Time.now, page.updated_on)) : nil))
          concat render_page_hierarchy(pages, page.id, options) if pages[page.id]
        end
      end.join.html_safe
    end
  end

  def error_messages_for(*params)
    objects, options = extract_objects_from_params(params)

    error_messages = objects.map{ |o| o.errors.full_messages }.flatten

    unless error_messages.empty?
      render partial: 'common/validation_error', locals: { error_messages: error_messages,
                                                           object_name: options[:object_name].to_s.gsub('_', '') }
    end
  end

  # Taken from Dynamic Form
  #
  # lib/action_view/helpers/dynamic_form.rb:187-198
  def extract_objects_from_params(params)
    options = params.extract_options!.symbolize_keys

    objects = Array.wrap(options.delete(:object) || params).map do |object|
      object = instance_variable_get("@#{object}") unless object.respond_to?(:to_model)
      object = convert_to_model(object)

      if object.class.respond_to?(:model_name)
        options[:object_name] ||= object.class.model_name.human.downcase
      end

      object
    end

    [objects.compact, options]
  end

  # Renders flash messages
  def render_flash_messages
    flash.map { |k,v| render_flash_message(k, v) }.join.html_safe
  end

  def join_flash_messages(messages)
    if messages.respond_to?(:join)
      messages.join('<br />').html_safe
    else
      messages
    end
  end

  def render_flash_message(type, message, html_options = {})
    html_options = { :class => "flash #{type} icon icon-#{type}", role: "alert" }.merge(html_options)
    if User.current.impaired?
      content_tag('div', content_tag('a', join_flash_messages(message), :href => 'javascript:;'), html_options)
    else
      content_tag('div', join_flash_messages(message), html_options)
    end
  end

  # Renders tabs and their content
  def render_tabs(tabs)
    if tabs.any?
      render :partial => 'common/tabs', :locals => {:tabs => tabs}
    else
      content_tag 'p', l(:label_no_data), :class => "nodata"
    end
  end

  def project_tree_options_for_select(projects, options = {}, &block)
    Project.project_level_list(projects).map do |element|

      tag_options = {
        :value => h(element[:project].id),
        :title => h(element[:project].name),
      }

      if options[:selected] == element[:project] ||
         (options[:selected].respond_to?(:include?) &&
          options[:selected].include?(element[:project]))

        tag_options[:selected] = 'selected'
      end

      level_prefix = ''
      level_prefix = ('&nbsp;' * 3 * element[:level] + '&#187; ').html_safe if element[:level] > 0

      tag_options.merge!(yield(element[:project])) if block_given?

      content_tag('option', level_prefix + h(element[:project].name), tag_options)
    end.join('').html_safe
  end

  # Yields the given block for each project with its level in the tree
  #
  # Wrapper for Project#project_tree
  def project_tree(projects, &block)
    Project.project_tree(projects, &block)
  end

  def project_nested_ul(projects, &block)
    s = ''
    if projects.any?
      ancestors = []
      Project.project_tree(projects) do |project, level|
        if (ancestors.empty? || project.is_descendant_of?(ancestors.last))
          s << "<ul>\n"
        else
          ancestors.pop
          s << "</li>"
          while (ancestors.any? && !project.is_descendant_of?(ancestors.last))
            ancestors.pop
            s << "</ul></li>\n"
          end
        end
        s << "<li>"
        s << yield(project).to_s
        ancestors << project
      end
      s << ("</li></ul>\n" * ancestors.size)
    end
    s.html_safe
  end

  def principals_check_box_tags(name, principals)
    labeled_check_box_tags(name, principals,
                                 { :title => :user_status_i18n,
                                   :class => :user_status_class })
  end

  def labeled_check_box_tags(name, collection, options = {})
    collection.sort.collect do |object|
      id = name.gsub(/[\[\]]+/,"_") + object.id.to_s

      object_options = options.inject({}) do |h, (k, v)|
        h[k] = v.is_a?(Symbol) ?
                 send(v, object) :
                 v

        h
      end

      content_tag :div do
        check_box_tag(name, object.id, false, :id => id) +
        label_tag(id, object, object_options)
      end
    end.join.html_safe
  end

  # Truncates and returns the string as a single line
  def truncate_single_line(string, *args)
    truncate(string.to_s, *args).gsub(%r{[\r\n]+}m, ' ')
  end

  # Truncates at line break after 250 characters or options[:length]
  def truncate_lines(string, options={})
    length = options[:length] || 250
    if string.to_s =~ /\A(.{#{length}}.*?)$/m
      "#{$1}..."
    else
      string
    end
  end

  def html_hours(text)
    text.gsub(%r{(\d+)\.(\d+)}, '<span class="hours hours-int">\1</span><span class="hours hours-dec">.\2</span>').html_safe
  end

  def authoring(created, author, options={})
    l(options[:label] || :label_added_time_by, :author => link_to_user(author), :age => time_tag(created)).html_safe
  end

  def time_tag(time)
    text = distance_of_time_in_words(Time.now, time)
    if @project and @project.module_enabled?("activity")
      link_to(text, {:controller => '/activities', :action => 'index', :project_id => @project, :from => time.to_date}, :title => format_time(time))
    else
      content_tag('label', text, :title => format_time(time), :class => "timestamp")
    end
  end

  def syntax_highlight(name, content)
    Redmine::SyntaxHighlighting.highlight_by_filename(content, name)
  end

  def to_path_param(path)
    path.to_s
  end


  def reorder_links(name, url, options = {})
    method = options[:method] || :post

    content_tag(:span,
      link_to(image_tag('2uparrow.png',   :alt => l(:label_sort_highest)), url.merge({"#{name}[move_to]" => 'highest'}), :method => method, :title => l(:label_sort_highest)) +
      link_to(image_tag('1uparrow.png',   :alt => l(:label_sort_higher)),  url.merge({"#{name}[move_to]" => 'higher'}),  :method => method, :title => l(:label_sort_higher)) +
      link_to(image_tag('1downarrow.png', :alt => l(:label_sort_lower)),   url.merge({"#{name}[move_to]" => 'lower'}),   :method => method, :title => l(:label_sort_lower)) +
      link_to(image_tag('2downarrow.png', :alt => l(:label_sort_lowest)),  url.merge({"#{name}[move_to]" => 'lowest'}),  :method => method, :title => l(:label_sort_lowest)),
      :class => "reorder-icons"
    )
  end

  def other_formats_links(&block)
    formats = capture(Redmine::Views::OtherFormatsBuilder.new(self), &block)
    unless formats.nil? || formats.strip.empty?
      content_tag 'p', :class => 'other-formats' do
        (l(:label_export_to) + formats).html_safe
      end
    end
  end

  # this method seems to not be used any more
  def page_header_title
    if @page_header_title.present?
      h(@page_header_title)
    elsif @project.nil? || @project.new_record?
      h(Setting.app_title)
    else
      b = []
      ancestors = (@project.root? ? [] : @project.ancestors.visible)
      if ancestors.any?
        root = ancestors.shift
        b << link_to_project(root, {:jump => current_menu_item}, :class => 'root')
        if ancestors.size > 2
          b << '&#8230;'
          ancestors = ancestors[-2, 2]
        end
        b += ancestors.collect {|p| link_to_project(p, {:jump => current_menu_item}, :class => 'ancestor') }
      end
      b << h(@project)
      b.join(' &#187; ')
    end
  end

  def html_title(*args)
    title = []

    if args.empty?
      title << h(@project.name) if @project
      title += @html_title if @html_title
      title << h(Setting.app_title)
    else
      @html_title ||= []
      @html_title += args
      title += @html_title
    end

    title.select {|t| !t.blank? }.join(' - ').html_safe
  end

  # Returns the theme, controller name, and action as css classes for the
  # HTML body.
  def body_css_classes
    css = ['theme-' + current_theme.identifier.to_s]
    if params[:controller] && params[:action]
      css << 'controller-' + params[:controller]
      css << 'action-' + params[:action]
    end
    css.join(' ')
  end

  def accesskey(s)
    OpenProject::AccessKeys.key_for s
  end

  # Formats text according to system settings.
  # 2 ways to call this method:
  # * with a String: textilizable(text, options)
  # * with an object and one of its attribute: textilizable(issue, :description, options)
  def textilizable(*args)
    options = args.last.is_a?(Hash) ? args.pop : {}
    case args.size
    when 1
      obj = options[:object]
      text = args.shift
    when 2
      obj = args.shift
      attr = args.shift
      text = obj.send(attr).to_s
    else
      raise ArgumentError, 'invalid arguments to textilizable'
    end
    return '' if text.blank?

    edit = !!options.delete(:edit)
    # don't return html in edit mode when textile or text formatting is enabled
    return text if edit
    project = options[:project] || @project || (obj && obj.respond_to?(:project) ? obj.project : nil)
    only_path = options.delete(:only_path) == false ? false : true

    text = Redmine::WikiFormatting.to_html(Setting.text_formatting, text, :object => obj, :attribute => attr, :edit => edit) { |macro, args| exec_macro(macro, obj, args, :view => self, :edit => edit) }

    #TODO: transform modifications into WikiFormatting Helper, or at least ask the helper if he wants his stuff to be modified
    @parsed_headings = []
    text = parse_non_pre_blocks(text) do |text|
      [:parse_inline_attachments, :parse_wiki_links, :parse_redmine_links, :parse_headings, :parse_relative_urls].each do |method_name|
        send method_name, text, project, obj, attr, only_path, options
      end
    end

    if @parsed_headings.any?
      replace_toc(text, @parsed_headings)
    end

    text.html_safe
  end
  alias_method :textilize, :textilizable

  def parse_non_pre_blocks(text)
    s = StringScanner.new(text)
    tags = []
    parsed = ''
    while !s.eos?
      s.scan(/(.*?)(<(\/)?(pre|code)(.*?)>|\z)/im)
      text, full_tag, closing, tag = s[1], s[2], s[3], s[4]
      if tags.empty?
        yield text
      end
      parsed << text
      if tag
        if closing
          if tags.last == tag.downcase
            tags.pop
          end
        else
          tags << tag.downcase
        end
        parsed << full_tag
      end
    end
    # Close any non closing tags
    while tag = tags.pop
      parsed << "</#{tag}>"
    end
    parsed
  end

  RELATIVE_LINK_RE = %r{
    <a
    (?:
      (\shref=
        (?:                         # the href and link
          (?:'(\/[^>]+?)')|
          (?:"(\/[^>]+?)")
        )
      )|
      [^>]
    )*
    >
    [^<]*?<\/a>                     # content and closing link tag.
  }x unless const_defined?(:RELATIVE_LINK_RE)

  def parse_relative_urls(text, project, obj, attr, only_path, options)
    return if only_path
    text.gsub!(RELATIVE_LINK_RE) do |m|
      href, relative_url = $1, $2 || $3
      next m unless href.present?
      if defined?(request) && request.present?
        # we have a request!
        protocol, host_with_port = request.protocol, request.host_with_port
      elsif @controller
        # use the same methods as url_for in the Mailer
        url_opts = @controller.class.default_url_options
        next m unless url_opts && url_opts[:protocol] && url_opts[:host]
        protocol, host_with_port = "#{url_opts[:protocol]}://", url_opts[:host]
      else
        next m
      end
      m.sub href, " href=\"#{protocol}#{host_with_port}#{relative_url}\""
    end
  end

  def parse_inline_attachments(text, project, obj, attr, only_path, options)
    # when using an image link, try to use an attachment, if possible
    if options[:attachments] || (obj && obj.respond_to?(:attachments))
      attachments = nil
      text.gsub!(/src="([^\/"]+\.(bmp|gif|jpg|jpeg|png))"(\s+alt="([^"]*)")?/i) do |m|
        filename, ext, alt, alttext = $1.downcase, $2, $3, $4
        attachments ||= (options[:attachments] || obj.attachments).sort_by(&:created_on).reverse
        # search for the picture in attachments
        if found = attachments.detect { |att| att.filename.downcase == filename }
          image_url = url_for :only_path => only_path, :controller => '/attachments', :action => 'download', :id => found
          desc = found.description.to_s.gsub('"', '')
          if !desc.blank? && alttext.blank?
            alt = " title=\"#{desc}\" alt=\"#{desc}\""
          end
          "src=\"#{image_url}\"#{alt}"
        else
          m
        end
      end
    end
  end

  # Wiki links
  #
  # Examples:
  #   [[mypage]]
  #   [[mypage|mytext]]
  # wiki links can refer other project wikis, using project name or identifier:
  #   [[project:]] -> wiki starting page
  #   [[project:|mytext]]
  #   [[project:mypage]]
  #   [[project:mypage|mytext]]
  def parse_wiki_links(text, project, obj, attr, only_path, options)
    text.gsub!(/(!)?(\[\[([^\]\n\|]+)(\|([^\]\n\|]+))?\]\])/) do |m|
      link_project = project
      esc, all, page, title = $1, $2, $3, $5
      if esc.nil?
        if page =~ /\A([^\:]+)\:(.*)\z/
          link_project = Project.find_by_identifier($1) || Project.find_by_name($1)
          page = $2
          title ||= $1 if page.blank?
        end

        if link_project && link_project.wiki
          # extract anchor
          anchor = nil
          if page =~ /\A(.+?)\#(.+)\z/
            page, anchor = $1, $2
          end
          # check if page exists
          wiki_page = link_project.wiki.find_page(page)
          url = case options[:wiki_links]
            when :local; "#{title}.html"
            when :anchor; "##{title}"   # used for single-file wiki export
            else
              wiki_page_id = page.present? ? Wiki.titleize(page) : nil
              url_for(:only_path => only_path, :controller => '/wiki', :action => 'show', :project_id => link_project, :id => wiki_page_id, :anchor => anchor)
            end
          link_to(h(title || page), url, :class => ('wiki-page' + (wiki_page ? '' : ' new')))
        else
          # project or wiki doesn't exist
          all
        end
      else
        all
      end
    end
  end

  # Redmine links
  #
  # Examples:
  #   Issues:
  #     #52 -> Link to issue #52
  #   Changesets:
  #     r52 -> Link to revision 52
  #     commit:a85130f -> Link to scmid starting with a85130f
  #   Documents:
  #     document#17 -> Link to document with id 17
  #     document:Greetings -> Link to the document with title "Greetings"
  #     document:"Some document" -> Link to the document with title "Some document"
  #   Versions:
  #     version#3 -> Link to version with id 3
  #     version:1.0.0 -> Link to version named "1.0.0"
  #     version:"1.0 beta 2" -> Link to version named "1.0 beta 2"
  #   Attachments:
  #     attachment:file.zip -> Link to the attachment of the current object named file.zip
  #   Source files:
  #     source:some/file -> Link to the file located at /some/file in the project's repository
  #     source:some/file@52 -> Link to the file's revision 52
  #     source:some/file#L120 -> Link to line 120 of the file
  #     source:some/file@52#L120 -> Link to line 120 of the file's revision 52
  #     export:some/file -> Force the download of the file
  #   Forum messages:
  #     message#1218 -> Link to message with id 1218
  #
  #   Links can refer other objects from other projects, using project identifier:
  #     identifier:r52
  #     identifier:document:"Some document"
  #     identifier:version:1.0.0
  #     identifier:source:some/file
  def parse_redmine_links(text, project, obj, attr, only_path, options)
    text.gsub!(%r{([\s\(,\-\[\>]|^)(!)?(([a-z0-9\-_]+):)?(attachment|version|commit|source|export|message|project)?((#+|r)(\d+)|(:)([^"\s<>][^\s<>]*?|"[^"]+?"))(?=(?=[[:punct:]]\W)|,|\s|\]|<|$)}) do |m|
      leading, esc, project_prefix, project_identifier, prefix, sep, identifier = $1, $2, $3, $4, $5, $7 || $9, $8 || $10
      link = nil
      if project_identifier
        project = Project.visible.find_by_identifier(project_identifier)
      end
      if esc.nil?
        if prefix.nil? && sep == 'r'
          # project.changesets.visible raises an SQL error because of a double join on repositories
          if project && project.repository && (changeset = Changeset.visible.find_by_repository_id_and_revision(project.repository.id, identifier))
            link = link_to(h("#{project_prefix}r#{identifier}"), {:only_path => only_path, :controller => '/repositories', :action => 'revision', :project_id => project, :rev => changeset.revision},
                                      :class => 'changeset',
                                      :title => truncate_single_line(changeset.comments, :length => 100))
          end
        elsif sep == '#'
          oid = identifier.to_i
          case prefix
          when nil
            if work_package = WorkPackage.visible.find_by_id(oid, :include => :status)
              link = link_to("##{oid}", work_package_path(:id => oid, :only_path => only_path),
                                        :class => work_package_css_classes(work_package),
                                        :title => "#{truncate(work_package.subject, :length => 100)} (#{work_package.status.try(:name)})")
            end
          when 'version'
            if version = Version.visible.find_by_id(oid)
              link = link_to h(version.name), {:only_path => only_path, :controller => '/versions', :action => 'show', :id => version},
                                              :class => 'version'
            end
          when 'message'
            if message = Message.visible.find_by_id(oid, :include => :parent)
              link = link_to_message(message, {:only_path => only_path}, :class => 'message')
            end
          when 'project'
            if p = Project.visible.find_by_id(oid)
              link = link_to_project(p, {:only_path => only_path}, :class => 'project')
            end
          end
        elsif sep == '##'
          oid = identifier.to_i
          if work_package = WorkPackage.visible.find_by_id(oid, :include => :status)
            link = work_package_quick_info(work_package)
          end
        elsif sep == '###'
          oid = identifier.to_i
          work_package = WorkPackage.visible.find_by_id(oid, :include => :status)
          if work_package && obj && !(attr == :description && obj.id == work_package.id)
            link = work_package_quick_info_with_description(work_package)
          end
        elsif sep == ':'
          # removes the double quotes if any
          name = identifier.gsub(%r{\A"(.*)"\z}, "\\1")
          case prefix
          when 'version'
            if project && version = project.versions.visible.find_by_name(name)
              link = link_to h(version.name), {:only_path => only_path, :controller => '/versions', :action => 'show', :id => version},
                                              :class => 'version'
            end
          when 'commit'
            if project && project.repository && (changeset = Changeset.visible.find(:first, :conditions => ["repository_id = ? AND scmid LIKE ?", project.repository.id, "#{name}%"]))
              link = link_to h("#{project_prefix}#{name}"), {:only_path => only_path, :controller => '/repositories', :action => 'revision', :project_id => project, :rev => changeset.identifier},
                                           :class => 'changeset',
                                           :title => truncate_single_line(h(changeset.comments), :length => 100)
            end
          when 'source', 'export'
            if project && project.repository && User.current.allowed_to?(:browse_repository, project)
              name =~ %r{\A[/\\]*(.*?)(@([0-9a-f]+))?(#(L\d+))?\z}
              path, rev, anchor = $1, $3, $5
              link = link_to h("#{project_prefix}#{prefix}:#{name}"), {:controller => '/repositories', :action => 'entry', :project_id => project,
                                                      :path => to_path_param(path),
                                                      :rev => rev,
                                                      :anchor => anchor,
                                                      :format => (prefix == 'export' ? 'raw' : nil)},
                                                     :class => (prefix == 'export' ? 'source download' : 'source')
            end
          when 'attachment'
            attachments = options[:attachments] || (obj && obj.respond_to?(:attachments) ? obj.attachments : nil)
            if attachments && attachment = attachments.detect {|a| a.filename == name }
              link = link_to h(attachment.filename), {:only_path => only_path, :controller => '/attachments', :action => 'download', :id => attachment},
                                                     :class => 'attachment'
            end
          when 'project'
            if p = Project.visible.find(:first, :conditions => ["identifier = :s OR LOWER(name) = :s", {:s => name.downcase}])
              link = link_to_project(p, {:only_path => only_path}, :class => 'project')
            end
          end
        end
      end
      leading + (link || "#{project_prefix}#{prefix}#{sep}#{identifier}")
    end
  end

  HEADING_RE = /<h(1|2|3|4)( [^>]+)?>(.+?)<\/h(1|2|3|4)>/i unless const_defined?(:HEADING_RE)

  # Headings and TOC
  # Adds ids and links to headings unless options[:headings] is set to false
  def parse_headings(text, project, obj, attr, only_path, options)
    return if options[:headings] == false

    text.gsub!(HEADING_RE) do
      level, attrs, content = $1.to_i, $2, $3
      item = strip_tags(content).strip
      anchor = item.gsub(%r{[^\w\s\-]}, '').gsub(%r{\s+(\-+\s*)?}, '-')
      @parsed_headings << [level, anchor, item]
      "<a name=\"#{anchor}\"></a>\n<h#{level} #{attrs}>#{content}<a href=\"##{anchor}\" class=\"wiki-anchor\">&para;</a></h#{level}>"
    end
  end

  TOC_RE = /<p>\{\{([<>]?)toc\}\}<\/p>/i unless const_defined?(:TOC_RE)

  # Renders the TOC with given headings
  def replace_toc(text, headings)
    text.gsub!(TOC_RE) do
      if headings.empty?
        ''
      else
        div_class = 'toc'
        div_class << ' right' if $1 == '>'
        div_class << ' left' if $1 == '<'
        out = "<fieldset class='header_collapsible collapsible'><legend title='" + l(:description_toc_toggle)+ "', onclick='toggleFieldset(this);'><a href='javascript:'>#{l(:label_table_of_contents)}</a></legend><div>"
        out << "<ul class=\"#{div_class}\"><li>"
        root = headings.map(&:first).min
        current = root
        started = false
        headings.each do |level, anchor, item|
          if level > current
            out << '<ul><li>' * (level - current)
          elsif level < current
            out << "</li></ul>\n" * (current - level) + "</li><li>"
          elsif started
            out << '</li><li>'
          end
          out << "<a href=\"##{anchor}\">#{item}</a>"
          current = level
          started = true
        end
        out << '</li></ul>' * (current - root)
        out << '</li></ul>'
        out << '</div></fieldset>'
      end
    end
  end

  # Same as Rails' simple_format helper without using paragraphs
  def simple_format_without_paragraph(text)
    text.to_s.
      gsub(/\r\n?/, "\n").                    # \r\n and \r -> \n
      gsub(/\n\n+/, "<br /><br />").          # 2+ newline  -> 2 br
      gsub(/([^\n]\n)(?=[^\n])/, '\1<br />').  # 1 newline   -> br
      html_safe
  end

  def lang_options_for_select(blank=true)
    auto = if (blank && (valid_languages - all_languages) == (all_languages - valid_languages))
            [["(auto)", ""]]
           else
            []
          end
    auto + valid_languages.collect{|lang| [ ll(lang.to_s, :general_lang_name), lang.to_s]}.sort{|x,y| x.last <=> y.last }
  end

  def all_lang_options_for_select(blank=true)
    (blank ? [["(auto)", ""]] : []) +
      all_languages.collect{|lang| [ ll(lang.to_s, :general_lang_name), lang.to_s]}.sort{|x,y| x.last <=> y.last }
  end

  def labelled_tabular_form_for(record, options = {}, &block)
    options.reverse_merge!(:builder => TabularFormBuilder, :lang => current_language, :html => {})
    options[:html][:class] = 'tabular' unless options[:html].has_key?(:class)
    form_for(record, options, &block)
  end

  def back_url_hidden_field_tag
    back_url = params[:back_url] || request.env['HTTP_REFERER']
    back_url = CGI.unescape(back_url.to_s)
    hidden_field_tag('back_url', CGI.escape(back_url)) unless back_url.blank?
  end

  def back_url_to_current_page_hidden_field_tag
    back_url = params[:back_url]
    if back_url.present?
      back_url = back_url.to_s
    elsif request.get? and !params.blank?
      back_url = url_for(params)
    end
    hidden_field_tag('back_url', back_url) unless back_url.blank?
  end

  def check_all_links(form_name)
    link_to_function(l(:button_check_all), "checkAll('#{form_name}', true)") +
    " | " +
    link_to_function(l(:button_uncheck_all), "checkAll('#{form_name}', false)")
  end

  def progress_bar(pcts, options={})
    pcts = [pcts, pcts] unless pcts.is_a?(Array)
    pcts = pcts.collect(&:round)
    pcts[1] = pcts[1] - pcts[0]
    pcts << (100 - pcts[1] - pcts[0])
    width = options[:width] || '100px;'
    legend = options[:legend] || ''

    bar = content_tag 'table', { :class => 'progress', :style => "width: #{width};" } do
      row = content_tag 'tr' do
        ((pcts[0] > 0 ? content_tag('td', '', :style => "width: #{pcts[0]}%;", :class => 'closed') : '') +
        (pcts[1] > 0 ? content_tag('td', '', :style => "width: #{pcts[1]}%;", :class => 'done') : '') +
        (pcts[2] > 0 ? content_tag('td', '', :style => "width: #{pcts[2]}%;", :class => 'todo') : '')).html_safe
      end
    end

    number = content_tag 'p', :class => 'pourcent' do
      legend + " " + l(:total_progress)
    end

    bar + number
  end

  def checked_image(checked=true)
    if checked
      icon_wrapper('icon-context icon-yes',l(:label_checked))
    end
  end

  def calendar_for(field_id)
    include_calendar_headers_tags
    javascript_tag("jQuery('##{field_id}').datepicker();")
  end

  def include_calendar_headers_tags
    unless @calendar_headers_tags_included
      @calendar_headers_tags_included = true
      content_for :header_tags do
        start_of_week = case Setting.start_of_week.to_i
        when 1
          '1' # Monday
        when 7
          '0' # Sunday
        when 6
          '6' # Saturday
        else
          '' # use language
        end
        js = "var CS = {lang: '#{current_language.to_s.downcase}', start: '#{start_of_week}'};"
        javascript_tag(js)
      end
    end
  end

  # Returns the javascript tags that are included in the html layout head
  def user_specific_javascript_includes
    tags = ''
    tags += javascript_tag(%Q{
      window.openProject = new OpenProject({
        urlRoot : '#{OpenProject::Configuration.rails_relative_url_root}',
        loginUrl: '#{url_for :controller => "/account", :action => "login"}'
      });
      I18n.defaultLocale = "#{I18n.default_locale}";
      I18n.locale = "#{I18n.locale}";
    })
    unless User.current.pref.warn_on_leaving_unsaved == '0'
      tags += javascript_tag("jQuery(function(){ new WarnLeavingUnsaved('#{escape_javascript( l(:text_warn_on_leaving_unsaved) )}'); });")
    end

    if User.current.impaired? and accessibility_js_enabled?
      tags += javascript_include_tag("accessibility.js")
    end

    tags.html_safe
  end

  # Add a HTML meta tag to control robots (web spiders)
  #
  # @param [optional, String] content the content of the ROBOTS tag.
  #   defaults to no index, follow, and no archive
  def robot_exclusion_tag(content="NOINDEX,FOLLOW,NOARCHIVE")
    "<meta name='ROBOTS' content='#{h(content)}' />".html_safe
  end

  # Returns true if arg is expected in the API response
  def include_in_api_response?(arg)
    unless @included_in_api_response
      param = params[:include]
      @included_in_api_response = param.is_a?(Array) ? param.collect(&:to_s) : param.to_s.split(',')
      @included_in_api_response.collect!(&:strip)
    end
    @included_in_api_response.include?(arg.to_s)
  end

  # Returns options or nil if nometa param or X-OpenProject-Nometa header
  # was set in the request
  def api_meta(options)
    if params[:nometa].present? || request.headers['X-OpenProject-Nometa']
      # compatibility mode for activeresource clients that raise
      # an error when unserializing an array with attributes
      nil
    else
      options
    end
  end

  # Expands the current menu item using JavaScript based on the params
  def expand_current_menu
    javascript_tag do
      raw "jQuery.menu_expand({ item: jQuery('#main-menu .selected').parents('#main-menu li').last().find('a').first() });"
    end
  end


  def disable_accessibility_css!
    @accessibility_css_disabled = true
  end

  def accessibility_css_enabled?
    !@accessibility_css_disabled
  end

  def disable_accessibility_js!
    @accessibility_js_disabled = true
  end

  def accessibility_js_enabled?
    !@accessibility_js_disabled
  end

  #
  # Returns the footer text displayed in the layout file.
  #
  def footer_content
    elements = []
    elements << I18n.t(:text_powered_by, :link => link_to(OpenProject::Info.app_name,
                                                          OpenProject::Info.url))
    unless OpenProject::Footer.content.nil?
      OpenProject::Footer.content.each do |name, value|
        content = value.respond_to?(:call) ? value.call : value
        if content
          elements << content_tag(:span, content, :class => "footer_#{name}")
        end
      end
    end
    elements << Setting.additional_footer_content if Setting.additional_footer_content.present?
    elements.join(", ").html_safe
  end

  private

  def wiki_helper
    helper = Redmine::WikiFormatting.helper_for(Setting.text_formatting)
    extend helper
    return self
  end

  def link_to_content_update(text, url_params = {}, html_options = {})
    link_to(text, url_params, html_options)
  end

  def password_complexity_requirements
    rules = OpenProject::Passwords::Evaluator.rules_description
    # use 0..0, so this doesn't fail if rules is an empty string
    rules[0] = rules[0..0].upcase

    s = raw "<em>" + OpenProject::Passwords::Evaluator.min_length_description + "</em>"
    s += raw "<br /><em>" + rules + "</em>" unless rules.empty?
    s
  end

  def icon_wrapper(icon_class, label)
    content =  content_tag(:span, '', :class => icon_class)
    content += content_tag(:span, label, :class => 'hidden-for-sighted')
  end

end