snippet.html.erb

<div class="day">
  <ul>
    <% date = Time.now+1.day %>
    <% price = 150 %>
    <% 7.times do |i| %>
      <% date  += 1.day %>
      <% price -= 10 %>
      <% if date.strftime("%u").to_i > 5 %>
        <% date = date+2.day %>
      <% end %>
      <li class="<%= i==0 ? "first" : "" %> <%= i==3 ? "active" : "" %>" data-price="<%= price %>" data-eta="<%= date.strftime("%a, %b %d") %>">
        <%= date.strftime("%b %d") %>
      </li>
    <% end %>
  </ul>
</div>

OUTPUT

<div class="day">
  <ul>
    <li class="first " data-price="140" data-eta="Mon, May 27">May 27</li>
    <li class=" " data-price="130" data-eta="Tue, May 28">May 28</li>
    <li class=" " data-price="120" data-eta="Wed, May 29">May 29</li>
    <li class=" active" data-price="110" data-eta="Thu, May 30">May 30</li>
    <li class=" " data-price="100" data-eta="Fri, May 31">May 31</li>
    <li class=" " data-price="90" data-eta="Mon, Jun 03">Jun 03</li>
    <li class=" " data-price="80" data-eta="Tue, Jun 04">Jun 04</li>
  </ul>
</div>