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+require 'active_support/core_ext/string/filters'
+require 'active_support/core_ext/array/extract_options'
+
+module ActionView
+ # = Action View Text Helpers
+ module Helpers #:nodoc:
+ # The TextHelper module provides a set of methods for filtering, formatting
+ # and transforming strings, which can reduce the amount of inline Ruby code in
+ # your views. These helper methods extend Action View making them callable
+ # within your template files.
+ #
+ # ==== Sanitization
+ #
+ # Most text helpers by default sanitize the given content, but do not escape it.
+ # This means HTML tags will appear in the page but all malicious code will be removed.
+ # Let's look at some examples using the +simple_format+ method:
+ #
+ # simple_format('<a href="http://example.com/">Example</a>')
+ # # => "<p><a href=\"http://example.com/\">Example</a></p>"
+ #
+ # simple_format('<a href="javascript:alert(\'no!\')">Example</a>')
+ # # => "<p><a>Example</a></p>"
+ #
+ # If you want to escape all content, you should invoke the +h+ method before
+ # calling the text helper.
+ #
+ # simple_format h('<a href="http://example.com/">Example</a>')
+ # # => "<p>&lt;a href=\"http://example.com/\"&gt;Example&lt;/a&gt;</p>"
+ module TextHelper
+ extend ActiveSupport::Concern
+
+ include SanitizeHelper
+ include TagHelper
+ # The preferred method of outputting text in your views is to use the
+ # <%= "text" %> eRuby syntax. The regular _puts_ and _print_ methods
+ # do not operate as expected in an eRuby code block. If you absolutely must
+ # output text within a non-output code block (i.e., <% %>), you can use the concat method.
+ #
+ # <%
+ # concat "hello"
+ # # is the equivalent of <%= "hello" %>
+ #
+ # if logged_in
+ # concat "Logged in!"
+ # else
+ # concat link_to('login', action: :login)
+ # end
+ # # will either display "Logged in!" or a login link
+ # %>
+ def concat(string)
+ output_buffer << string
+ end
+
+ def safe_concat(string)
+ output_buffer.respond_to?(:safe_concat) ? output_buffer.safe_concat(string) : concat(string)
+ end
+
+ # Truncates a given +text+ after a given <tt>:length</tt> if +text+ is longer than <tt>:length</tt>
+ # (defaults to 30). The last characters will be replaced with the <tt>:omission</tt> (defaults to "...")
+ # for a total length not exceeding <tt>:length</tt>.
+ #
+ # Pass a <tt>:separator</tt> to truncate +text+ at a natural break.
+ #
+ # Pass a block if you want to show extra content when the text is truncated.
+ #
+ # The result is marked as HTML-safe, but it is escaped by default, unless <tt>:escape</tt> is
+ # +false+. Care should be taken if +text+ contains HTML tags or entities, because truncation
+ # may produce invalid HTML (such as unbalanced or incomplete tags).
+ #
+ # truncate("Once upon a time in a world far far away")
+ # # => "Once upon a time in a world..."
+ #
+ # truncate("Once upon a time in a world far far away", length: 17)
+ # # => "Once upon a ti..."
+ #
+ # truncate("Once upon a time in a world far far away", length: 17, separator: ' ')
+ # # => "Once upon a..."
+ #
+ # truncate("And they found that many people were sleeping better.", length: 25, omission: '... (continued)')
+ # # => "And they f... (continued)"
+ #
+ # truncate("<p>Once upon a time in a world far far away</p>")
+ # # => "<p>Once upon a time in a wo..."
+ #
+ # truncate("Once upon a time in a world far far away") { link_to "Continue", "#" }
+ # # => "Once upon a time in a wo...<a href="#">Continue</a>"
+ def truncate(text, options = {}, &block)
+ if text
+ length = options.fetch(:length, 30)
+
+ content = text.truncate(length, options)
+ content = options[:escape] == false ? content.html_safe : ERB::Util.html_escape(content)
+ content << capture(&block) if block_given? && text.length > length
+ content
+ end
+ end
+
+ # Highlights one or more +phrases+ everywhere in +text+ by inserting it into
+ # a <tt>:highlighter</tt> string. The highlighter can be specialized by passing <tt>:highlighter</tt>
+ # as a single-quoted string with <tt>\1</tt> where the phrase is to be inserted (defaults to
+ # '<mark>\1</mark>')
+ #
+ # highlight('You searched for: rails', 'rails')
+ # # => You searched for: <mark>rails</mark>
+ #
+ # highlight('You searched for: ruby, rails, dhh', 'actionpack')
+ # # => You searched for: ruby, rails, dhh
+ #
+ # highlight('You searched for: rails', ['for', 'rails'], highlighter: '<em>\1</em>')
+ # # => You searched <em>for</em>: <em>rails</em>
+ #
+ # highlight('You searched for: rails', 'rails', highlighter: '<a href="search?q=\1">\1</a>')
+ # # => You searched for: <a href="search?q=rails">rails</a>
+ def highlight(text, phrases, options = {})
+ text = sanitize(text) if options.fetch(:sanitize, true)
+
+ if text.blank? || phrases.blank?
+ text
+ else
+ highlighter = options.fetch(:highlighter, '<mark>\1</mark>')
+ match = Array(phrases).map { |p| Regexp.escape(p) }.join('|')
+ text.gsub(/(#{match})(?![^<]*?>)/i, highlighter)
+ end.html_safe
+ end
+
+ # Extracts an excerpt from +text+ that matches the first instance of +phrase+.
+ # The <tt>:radius</tt> option expands the excerpt on each side of the first occurrence of +phrase+ by the number of characters
+ # defined in <tt>:radius</tt> (which defaults to 100). If the excerpt radius overflows the beginning or end of the +text+,
+ # then the <tt>:omission</tt> option (which defaults to "...") will be prepended/appended accordingly. Use the
+ # <tt>:separator</tt> option to choose the delimitation. The resulting string will be stripped in any case. If the +phrase+
+ # isn't found, nil is returned.
+ #
+ # excerpt('This is an example', 'an', radius: 5)
+ # # => ...s is an exam...
+ #
+ # excerpt('This is an example', 'is', radius: 5)
+ # # => This is a...
+ #
+ # excerpt('This is an example', 'is')
+ # # => This is an example
+ #
+ # excerpt('This next thing is an example', 'ex', radius: 2)
+ # # => ...next...
+ #
+ # excerpt('This is also an example', 'an', radius: 8, omission: '<chop> ')
+ # # => <chop> is also an example
+ #
+ # excerpt('This is a very beautiful morning', 'very', separator: ' ', radius: 1)
+ # # => ...a very beautiful...
+ def excerpt(text, phrase, options = {})
+ return unless text && phrase
+
+ separator = options.fetch(:separator, "")
+ phrase = Regexp.escape(phrase)
+ regex = /#{phrase}/i
+
+ return unless matches = text.match(regex)
+ phrase = matches[0]
+
+ text.split(separator).each do |value|
+ if value.match(regex)
+ regex = phrase = value
+ break
+ end
+ end
+
+ first_part, second_part = text.split(regex, 2)
+
+ prefix, first_part = cut_excerpt_part(:first, first_part, separator, options)
+ postfix, second_part = cut_excerpt_part(:second, second_part, separator, options)
+
+ prefix + (first_part + separator + phrase + separator + second_part).strip + postfix
+ end
+
+ # Attempts to pluralize the +singular+ word unless +count+ is 1. If
+ # +plural+ is supplied, it will use that when count is > 1, otherwise
+ # it will use the Inflector to determine the plural form.
+ #
+ # pluralize(1, 'person')
+ # # => 1 person
+ #
+ # pluralize(2, 'person')
+ # # => 2 people
+ #
+ # pluralize(3, 'person', 'users')
+ # # => 3 users
+ #
+ # pluralize(0, 'person')
+ # # => 0 people
+ def pluralize(count, singular, plural = nil)
+ word = if (count == 1 || count =~ /^1(\.0+)?$/)
+ singular
+ else
+ plural || singular.pluralize
+ end
+
+ "#{count || 0} #{word}"
+ end
+
+ # Wraps the +text+ into lines no longer than +line_width+ width. This method
+ # breaks on the first whitespace character that does not exceed +line_width+
+ # (which is 80 by default).
+ #
+ # word_wrap('Once upon a time')
+ # # => Once upon a time
+ #
+ # word_wrap('Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding a successor to the throne turned out to be more trouble than anyone could have imagined...')
+ # # => Once upon a time, in a kingdom called Far Far Away, a king fell ill, and finding\na successor to the throne turned out to be more trouble than anyone could have\nimagined...
+ #
+ # word_wrap('Once upon a time', line_width: 8)
+ # # => Once\nupon a\ntime
+ #
+ # word_wrap('Once upon a time', line_width: 1)
+ # # => Once\nupon\na\ntime
+ def word_wrap(text, options = {})
+ line_width = options.fetch(:line_width, 80)
+
+ text.split("\n").collect do |line|
+ line.length > line_width ? line.gsub(/(.{1,#{line_width}})(\s+|$)/, "\\1\n").strip : line
+ end * "\n"
+ end
+
+ # Returns +text+ transformed into HTML using simple formatting rules.
+ # Two or more consecutive newlines(<tt>\n\n</tt>) are considered as a
+ # paragraph and wrapped in <tt><p></tt> tags. One newline (<tt>\n</tt>) is
+ # considered as a linebreak and a <tt><br /></tt> tag is appended. This
+ # method does not remove the newlines from the +text+.
+ #
+ # You can pass any HTML attributes into <tt>html_options</tt>. These
+ # will be added to all created paragraphs.
+ #
+ # ==== Options
+ # * <tt>:sanitize</tt> - If +false+, does not sanitize +text+.
+ # * <tt>:wrapper_tag</tt> - String representing the wrapper tag, defaults to <tt>"p"</tt>
+ #
+ # ==== Examples
+ # my_text = "Here is some basic text...\n...with a line break."
+ #
+ # simple_format(my_text)
+ # # => "<p>Here is some basic text...\n<br />...with a line break.</p>"
+ #
+ # simple_format(my_text, {}, wrapper_tag: "div")
+ # # => "<div>Here is some basic text...\n<br />...with a line break.</div>"
+ #
+ # more_text = "We want to put a paragraph...\n\n...right there."
+ #
+ # simple_format(more_text)
+ # # => "<p>We want to put a paragraph...</p>\n\n<p>...right there.</p>"
+ #
+ # simple_format("Look ma! A class!", class: 'description')
+ # # => "<p class='description'>Look ma! A class!</p>"
+ #
+ # simple_format("<blink>Unblinkable.</blink>")
+ # # => "<p>Unblinkable.</p>"
+ #
+ # simple_format("<blink>Blinkable!</blink> It's true.", {}, sanitize: false)
+ # # => "<p><blink>Blinkable!</span> It's true.</p>"
+ def simple_format(text, html_options = {}, options = {})
+ wrapper_tag = options.fetch(:wrapper_tag, :p)
+
+ text = sanitize(text) if options.fetch(:sanitize, true)
+ paragraphs = split_paragraphs(text)
+
+ if paragraphs.empty?
+ content_tag(wrapper_tag, nil, html_options)
+ else
+ paragraphs.map { |paragraph|
+ content_tag(wrapper_tag, paragraph, html_options, options[:sanitize])
+ }.join("\n\n").html_safe
+ end
+ end
+
+ # Creates a Cycle object whose _to_s_ method cycles through elements of an
+ # array every time it is called. This can be used for example, to alternate
+ # classes for table rows. You can use named cycles to allow nesting in loops.
+ # Passing a Hash as the last parameter with a <tt>:name</tt> key will create a
+ # named cycle. The default name for a cycle without a +:name+ key is
+ # <tt>"default"</tt>. You can manually reset a cycle by calling reset_cycle
+ # and passing the name of the cycle. The current cycle string can be obtained
+ # anytime using the current_cycle method.
+ #
+ # # Alternate CSS classes for even and odd numbers...
+ # @items = [1,2,3,4]
+ # <table>
+ # <% @items.each do |item| %>
+ # <tr class="<%= cycle("odd", "even") -%>">
+ # <td>item</td>
+ # </tr>
+ # <% end %>
+ # </table>
+ #
+ #
+ # # Cycle CSS classes for rows, and text colors for values within each row
+ # @items = x = [{first: 'Robert', middle: 'Daniel', last: 'James'},
+ # {first: 'Emily', middle: 'Shannon', maiden: 'Pike', last: 'Hicks'},
+ # {first: 'June', middle: 'Dae', last: 'Jones'}]
+ # <% @items.each do |item| %>
+ # <tr class="<%= cycle("odd", "even", name: "row_class") -%>">
+ # <td>
+ # <% item.values.each do |value| %>
+ # <%# Create a named cycle "colors" %>
+ # <span style="color:<%= cycle("red", "green", "blue", name: "colors") -%>">
+ # <%= value %>
+ # </span>
+ # <% end %>
+ # <% reset_cycle("colors") %>
+ # </td>
+ # </tr>
+ # <% end %>
+ def cycle(first_value, *values)
+ options = values.extract_options!
+ name = options.fetch(:name, 'default')
+
+ values.unshift(first_value)
+
+ cycle = get_cycle(name)
+ unless cycle && cycle.values == values
+ cycle = set_cycle(name, Cycle.new(*values))
+ end
+ cycle.to_s
+ end
+
+ # Returns the current cycle string after a cycle has been started. Useful
+ # for complex table highlighting or any other design need which requires
+ # the current cycle string in more than one place.
+ #
+ # # Alternate background colors
+ # @items = [1,2,3,4]
+ # <% @items.each do |item| %>
+ # <div style="background-color:<%= cycle("red","white","blue") %>">
+ # <span style="background-color:<%= current_cycle %>"><%= item %></span>
+ # </div>
+ # <% end %>
+ def current_cycle(name = "default")
+ cycle = get_cycle(name)
+ cycle.current_value if cycle
+ end
+
+ # Resets a cycle so that it starts from the first element the next time
+ # it is called. Pass in +name+ to reset a named cycle.
+ #
+ # # Alternate CSS classes for even and odd numbers...
+ # @items = [[1,2,3,4], [5,6,3], [3,4,5,6,7,4]]
+ # <table>
+ # <% @items.each do |item| %>
+ # <tr class="<%= cycle("even", "odd") -%>">
+ # <% item.each do |value| %>
+ # <span style="color:<%= cycle("#333", "#666", "#999", name: "colors") -%>">
+ # <%= value %>
+ # </span>
+ # <% end %>
+ #
+ # <% reset_cycle("colors") %>
+ # </tr>
+ # <% end %>
+ # </table>
+ def reset_cycle(name = "default")
+ cycle = get_cycle(name)
+ cycle.reset if cycle
+ end
+
+ class Cycle #:nodoc:
+ attr_reader :values
+
+ def initialize(first_value, *values)
+ @values = values.unshift(first_value)
+ reset
+ end
+
+ def reset
+ @index = 0
+ end
+
+ def current_value
+ @values[previous_index].to_s
+ end
+
+ def to_s
+ value = @values[@index].to_s
+ @index = next_index
+ return value
+ end
+
+ private
+
+ def next_index
+ step_index(1)
+ end
+
+ def previous_index
+ step_index(-1)
+ end
+
+ def step_index(n)
+ (@index + n) % @values.size
+ end
+ end
+
+ private
+ # The cycle helpers need to store the cycles in a place that is
+ # guaranteed to be reset every time a page is rendered, so it
+ # uses an instance variable of ActionView::Base.
+ def get_cycle(name)
+ @_cycles = Hash.new unless defined?(@_cycles)
+ return @_cycles[name]
+ end
+
+ def set_cycle(name, cycle_object)
+ @_cycles = Hash.new unless defined?(@_cycles)
+ @_cycles[name] = cycle_object
+ end
+
+ def split_paragraphs(text)
+ return [] if text.blank?
+
+ text.to_str.gsub(/\r\n?/, "\n").split(/\n\n+/).map! do |t|
+ t.gsub!(/([^\n]\n)(?=[^\n])/, '\1<br />') || t
+ end
+ end
+
+ def cut_excerpt_part(part_position, part, separator, options)
+ return "", "" unless part
+
+ radius = options.fetch(:radius, 100)
+ omission = options.fetch(:omission, "...")
+
+ part = part.split(separator)
+ part.delete("")
+ affix = part.size > radius ? omission : ""
+
+ part = if part_position == :first
+ drop_index = [part.length - radius, 0].max
+ part.drop(drop_index)
+ else
+ part.first(radius)
+ end
+
+ return affix, part.join(separator)
+ end
+ end
+ end
+end