module SinatraMore
  module FormatHelpers

    # Returns escaped text to protect against malicious content
    def escape_html(text)
      Rack::Utils.escape_html(text)
    end
    alias h escape_html
    alias sanitize_html escape_html

    # Returns escaped text to protect against malicious content
    # Returns blank if the text is empty
    def h!(text, blank_text = ' ')
      return blank_text if text.nil? || text.empty?
      h text
    end


    # Smart time helper which returns relative text representing times for recent dates
    # and absolutes for dates that are far removed from the current date
    # time_in_words(10.days.ago) => '10 days ago'
    def time_in_words(date)
      date = date.to_date
      date = Date.parse(date, true) unless /Date.*/ =~ date.class.to_s
      days = (date - Date.today).to_i

      return 'today'     if days >= 0 and days < 1
      return 'tomorrow'  if days >= 1 and days < 2
      return 'yesterday' if days >= -1 and days < 0

      return "in #{days} days"      if days.abs < 60 and days > 0
      return "#{days.abs} days ago" if days.abs < 60 and days < 0

      return date.strftime('%A, %B %e') if days.abs < 182
      return date.strftime('%A, %B %e, %Y')
    end
    alias time_ago time_in_words

    # Returns relative time in words referencing the given date
    # relative_time_ago(Time.now) => 'about a minute ago'
    def relative_time_ago(from_time)
      distance_in_minutes = (((Time.now - from_time.to_time).abs)/60).round
      case distance_in_minutes
        when 0..1 then 'about a minute'
        when 2..44 then "#{distance_in_minutes} minutes"
        when 45..89 then 'about 1 hour'
        when 90..1439 then "about #{(distance_in_minutes.to_f / 60.0).round} hours"
        when 1440..2879 then '1 day'
        when 2880..43199 then "#{(distance_in_minutes / 1440).round} days"
        when 43200..86399 then 'about 1 month'
        when 86400..525599 then "#{(distance_in_minutes / 43200).round} months"
        when 525600..1051199 then 'about 1 year'
        else "over #{(distance_in_minutes / 525600).round} years"
      end
    end

    # Used in xxxx.js.erb files to escape html so that it can be passed to javascript from sinatra
    # escape_javascript("<h1>Hey</h1>")
    def escape_javascript(html_content)
      return '' unless html_content
      javascript_mapping = { '\\' => '\\\\', '</' => '<\/', "\r\n" => '\n', "\n" => '\n' }
      javascript_mapping.merge("\r" => '\n', '"' => '\\"', "'" => "\\'")
      escaped_string = html_content.gsub(/(\\|<\/|\r\n|[\n\r"'])/) { javascript_mapping[$1] }
      "\"#{escaped_string}\""
    end

    alias js_escape escape_javascript
    alias js_escape_html escape_javascript
    alias escape_for_javascript escape_javascript

  end
end