~michaelforrest/use-case-mapper/trunk

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
require 'action_view/helpers/tag_helper'
require 'action_view/helpers/prototype_helper'

module ActionView
  module Helpers
    # Provides functionality for working with JavaScript in your views.
    #
    # == Ajax, controls and visual effects
    #
    # * For information on using Ajax, see
    #   ActionView::Helpers::PrototypeHelper.
    # * For information on using controls and visual effects, see
    #   ActionView::Helpers::ScriptaculousHelper.
    #
    # == Including the JavaScript libraries into your pages
    #
    # Rails includes the Prototype JavaScript framework and the Scriptaculous
    # JavaScript controls and visual effects library.  If you wish to use
    # these libraries and their helpers (ActionView::Helpers::PrototypeHelper
    # and ActionView::Helpers::ScriptaculousHelper), you must do one of the
    # following:
    #
    # * Use <tt><%= javascript_include_tag :defaults %></tt> in the HEAD
    #   section of your page (recommended): This function will return
    #   references to the JavaScript files created by the +rails+ command in
    #   your <tt>public/javascripts</tt> directory. Using it is recommended as
    #   the browser can then cache the libraries instead of fetching all the
    #   functions anew on every request.
    # * Use <tt><%= javascript_include_tag 'prototype' %></tt>: As above, but
    #   will only include the Prototype core library, which means you are able
    #   to use all basic AJAX functionality. For the Scriptaculous-based
    #   JavaScript helpers, like visual effects, autocompletion, drag and drop
    #   and so on, you should use the method described above.
    #
    # For documentation on +javascript_include_tag+ see
    # ActionView::Helpers::AssetTagHelper.
    module JavaScriptHelper
      unless const_defined? :JAVASCRIPT_PATH
        JAVASCRIPT_PATH = File.join(File.dirname(__FILE__), 'javascripts')
      end

      include PrototypeHelper

      # Returns a link of the given +name+ that will trigger a JavaScript +function+ using the
      # onclick handler and return false after the fact.
      #
      # The first argument +name+ is used as the link text.
      #
      # The next arguments are optional and may include the javascript function definition and a hash of html_options.
      #
      # The +function+ argument can be omitted in favor of an +update_page+
      # block, which evaluates to a string when the template is rendered
      # (instead of making an Ajax request first).
      #
      # The +html_options+ will accept a hash of html attributes for the link tag. Some examples are :class => "nav_button", :id => "articles_nav_button"
      #
      # Note: if you choose to specify the javascript function in a block, but would like to pass html_options, set the +function+ parameter to nil
      #
      #
      # Examples:
      #   link_to_function "Greeting", "alert('Hello world!')"
      #     Produces:
      #       <a onclick="alert('Hello world!'); return false;" href="#">Greeting</a>
      #
      #   link_to_function(image_tag("delete"), "if (confirm('Really?')) do_delete()")
      #     Produces:
      #       <a onclick="if (confirm('Really?')) do_delete(); return false;" href="#">
      #         <img src="/images/delete.png?" alt="Delete"/>
      #       </a>
      #
      #   link_to_function("Show me more", nil, :id => "more_link") do |page|
      #     page[:details].visual_effect  :toggle_blind
      #     page[:more_link].replace_html "Show me less"
      #   end
      #     Produces:
      #       <a href="#" id="more_link" onclick="try {
      #         $(&quot;details&quot;).visualEffect(&quot;toggle_blind&quot;);
      #         $(&quot;more_link&quot;).update(&quot;Show me less&quot;);
      #       }
      #       catch (e) {
      #         alert('RJS error:\n\n' + e.toString());
      #         alert('$(\&quot;details\&quot;).visualEffect(\&quot;toggle_blind\&quot;);
      #         \n$(\&quot;more_link\&quot;).update(\&quot;Show me less\&quot;);');
      #         throw e
      #       };
      #       return false;">Show me more</a>
      #
      def link_to_function(name, *args, &block)
        html_options = args.extract_options!.symbolize_keys

        function = block_given? ? update_page(&block) : args[0] || ''
        onclick = "#{"#{html_options[:onclick]}; " if html_options[:onclick]}#{function}; return false;"
        href = html_options[:href] || '#'

        content_tag(:a, name, html_options.merge(:href => href, :onclick => onclick))
      end

      # Returns a button with the given +name+ text that'll trigger a JavaScript +function+ using the
      # onclick handler.
      #
      # The first argument +name+ is used as the button's value or display text.
      #
      # The next arguments are optional and may include the javascript function definition and a hash of html_options.
      #
      # The +function+ argument can be omitted in favor of an +update_page+
      # block, which evaluates to a string when the template is rendered
      # (instead of making an Ajax request first).
      #
      # The +html_options+ will accept a hash of html attributes for the link tag. Some examples are :class => "nav_button", :id => "articles_nav_button"
      #
      # Note: if you choose to specify the javascript function in a block, but would like to pass html_options, set the +function+ parameter to nil
      #
      # Examples:
      #   button_to_function "Greeting", "alert('Hello world!')"
      #   button_to_function "Delete", "if (confirm('Really?')) do_delete()"
      #   button_to_function "Details" do |page|
      #     page[:details].visual_effect :toggle_slide
      #   end
      #   button_to_function "Details", :class => "details_button" do |page|
      #     page[:details].visual_effect :toggle_slide
      #   end
      def button_to_function(name, *args, &block)
        html_options = args.extract_options!.symbolize_keys

        function = block_given? ? update_page(&block) : args[0] || ''
        onclick = "#{"#{html_options[:onclick]}; " if html_options[:onclick]}#{function};"

        tag(:input, html_options.merge(:type => 'button', :value => name, :onclick => onclick))
      end

      JS_ESCAPE_MAP = {
        '\\'    => '\\\\',
        '</'    => '<\/',
        "\r\n"  => '\n',
        "\n"    => '\n',
        "\r"    => '\n',
        '"'     => '\\"',
        "'"     => "\\'" }

      # Escape carrier returns and single and double quotes for JavaScript segments.
      def escape_javascript(javascript)
        if javascript
          javascript.gsub(/(\\|<\/|\r\n|[\n\r"'])/) { JS_ESCAPE_MAP[$1] }
        else
          ''
        end
      end

      # Returns a JavaScript tag with the +content+ inside. Example:
      #   javascript_tag "alert('All is good')"
      #
      # Returns:
      #   <script type="text/javascript">
      #   //<![CDATA[
      #   alert('All is good')
      #   //]]>
      #   </script>
      #
      # +html_options+ may be a hash of attributes for the <script> tag. Example:
      #   javascript_tag "alert('All is good')", :defer => 'defer'
      #   # => <script defer="defer" type="text/javascript">alert('All is good')</script>
      #
      # Instead of passing the content as an argument, you can also use a block
      # in which case, you pass your +html_options+ as the first parameter.
      #   <% javascript_tag :defer => 'defer' do -%>
      #     alert('All is good')
      #   <% end -%>
      def javascript_tag(content_or_options_with_block = nil, html_options = {}, &block)
        content =
          if block_given?
            html_options = content_or_options_with_block if content_or_options_with_block.is_a?(Hash)
            capture(&block)
          else
            content_or_options_with_block
          end

        tag = content_tag(:script, javascript_cdata_section(content), html_options.merge(:type => Mime::JS))

        if block_called_from_erb?(block)
          concat(tag)
        else
          tag
        end
      end

      def javascript_cdata_section(content) #:nodoc:
        "\n//#{cdata_section("\n#{content}\n//")}\n"
      end

    protected
      def options_for_javascript(options)
        if options.empty?
          '{}'
        else
          "{#{options.keys.map { |k| "#{k}:#{options[k]}" }.sort.join(', ')}}"
        end
      end

      def array_or_string_for_javascript(option)
        if option.kind_of?(Array)
          "['#{option.join('\',\'')}']"
        elsif !option.nil?
          "'#{option}'"
        end
      end
    end
  end
end