module MessageTags
  include Radiant::Taggable
  include ReaderHelper
  
  class TagError < StandardError; end

  # I can see this causing problems: will change soon

  desc %{
    The root 'site' tag is not meant to be called directly. 
    All it does is to prepare the way for eg.
    <pre><code><r:site:url /></code></pre>
  }
  tag 'site' do |tag|
    raise TagError, "r:site currently only works in email" unless @mailer_vars
    raise TagError, "no site" unless tag.locals.site = @mailer_vars[:@site]
    tag.expand
  end
  tag 'site:name' do |tag|
    if defined?(Site) && tag.locals.site.is_a?(Site)
      tag.locals.site.name
    else
      tag.locals.site[:name]
    end
  end
  tag 'site:url' do |tag|
    if defined?(Site) && tag.locals.site.is_a?(Site)
      tag.locals.site.base_domain
    else
      tag.locals.site[:url]
    end
  end
  tag 'site:login_url' do |tag|
    reader_login_url(:host => @mailer_vars[:@host])
  end

  desc %{
    The root 'recipient' tag is not meant to be called directly. 
    All it does is summon a reader object so that its fields can be displayed with eg.
    <pre><code><r:recipient:name /></code></pre>
  }
  tag 'recipient' do |tag|
    raise TagError, "r:recipient only works in email" unless @mailer_vars
    raise TagError, "no recipient" unless tag.locals.recipient = @mailer_vars[:@reader]
    tag.expand
  end

  [:name, :forename, :surname, :email, :description, :login].each do |field|
    desc %{
      Only for use in email messages. Displays the #{field} field of the reader currently being emailed.
      <pre><code><r:recipient:#{field} /></code></pre>
    }
    tag "recipient:#{field}" do |tag|
      tag.locals.recipient.send(field)
    end
  end

  desc %{
    Only for use in email messages. Displays the password of the reader currently being emailed, if we still have it.

    (After the first successful login we forget the cleartext version of their password, so in normal use you would 
    only see this tag in welcome and activation messages.)
  
    <pre><code><r:recipient:url /></code></pre>
  }
  tag "recipient:password" do |tag|
    tag.locals.recipient.clear_password || "<encrypted>"
  end

  desc %{
    Only for use in email messages. Displays the me-page url of the reader currently being emailed.
    <pre><code><r:recipient:url /></code></pre>
  }
  tag "recipient:url" do |tag|
    reader_url(tag.locals.recipient, :host => @mailer_vars[:@host])
  end

  desc %{
    Only for use in email messages. Displays the preferences url of the reader currently being emailed.
    <pre><code><r:recipient:edit_preferences_url /></code></pre>
  }
  tag "recipient:edit_preferences_url" do |tag|
    
    Rails.logger.warn "and the :host argument will be #{@mailer_vars[:@host]}"
    Rails.logger.warn "giving us #{reader_account_url(:host => @mailer_vars[:@host])}"
    
    reader_account_url(:host => @mailer_vars[:@host])
  end

  desc %{
    Please replace your old r:recipient:edit_url tags with either `r:recipient:edit_profile_url` or `r:recipient:edit_preferences_url`.
    <pre><code><r:recipient:edit_url /></code></pre>
  }
  deprecated_tag "recipient:edit_url", :substitute => 'recipient:edit_preferences_url'

  desc %{
    Only for use in email messages. Displays the edit-my-profile url of the reader currently being emailed.
    <pre><code><r:recipient:edit_profile_url /></code></pre>
  }
  tag "recipient:edit_profile_url" do |tag|
    reader_edit_profile_url(:host => @mailer_vars[:@host])
  end

  desc %{
    Only for use in email messages. Displays the address that will activate the current reader account.
    <pre><code><r:recipient:activation_url /></code></pre>
  }
  tag "recipient:activation_url" do |tag|
    activate_me_url(tag.locals.recipient, :activation_code => tag.locals.recipient.perishable_token, :host => @mailer_vars[:@host])
  end

  desc %{
    Only for use in email messages. Displays the address that will bring up a new-password form for the current reader account.
    <pre><code><r:recipient:repassword_url /></code></pre>
  }
  tag "recipient:repassword_url" do |tag|
    repassword_me_url(tag.locals.recipient, :confirmation_code => tag.locals.recipient.perishable_token, :host => @mailer_vars[:@host])
  end

  desc %{
    The root 'sender' tag is not meant to be called directly. 
    All it does is summon a sender object so that its fields can be displayed with eg.
    <pre><code><r:sender:name /></code></pre>
  }
  tag 'sender' do |tag|
    raise TagError, "r:sender only works in email" unless @mailer_vars
    tag.expand
  end

  desc %{
    Only for use in email messages. Displays the name of the email-sender (which is probably configured in `email.name`)
    <pre><code><r:sender:name /></code></pre>
  }
  tag "sender:name" do |tag|
    @mailer_vars['sender']
  end

  desc %{
    Only for use in email messages. Displays the address of the email-sender (which is probably configured in `email.address`)
    <pre><code><r:sender:address /></code></pre>
  }
  tag "sender:address" do |tag|
    @mailer_vars['reply_to']
  end

  # and for referring to messages on pages
  # at the moment this only works inside r:reader:messages:each or r:group:messages:each, 
  # both of which are defined in reader_group
  # but soon there will be a conditional r:messages:each tag here too

  desc %{
    The root 'message' tag is not meant to be called directly. 
    All it does is summon a message object so that its fields can be displayed with eg.
    <pre><code><r:message:subject /></code></pre>
  }
  tag 'message' do |tag|
    raise TagError, "no message!" unless tag.locals.message
    tag.expand
  end

  desc %{
    Displays the message subject.
  
    <pre><code><r:message:subject /></code></pre>
  }
  tag "message:subject" do |tag|
    tag.locals.message.subject
  end

  desc %{
    Displays the formatted message body.
  
    <pre><code><r:message:body /></code></pre>
  }
  tag "message:body" do |tag|
    tag.locals.message.filtered_body
  end

  desc %{
    Returns the url of the show-message page.
  
    <pre><code><r:message:url /></code></pre>
  }
  tag "message:url" do |tag|
    preview_message_path(tag.locals.message)
  end

  desc %{
    Displays a link to the show-message page.
  
    <pre><code><r:message:link /></code></pre>
  }
  tag "message:link" do |tag|
    options = tag.attr.dup
    attributes = options.inject('') { |s, (k, v)| s << %{#{k.downcase}="#{v}" } }.strip
    attributes = " #{attributes}" unless attributes.empty?
    text = tag.double? ? tag.expand : tag.render('message:subject')
    %{<a href="#{tag.render('message:url')}"#{attributes}>#{text}</a>}
  end

end