Some(page_index - 1)
      } else {
        None
      },
      next_page: if (page_index + 1) * 100 <= num_inscriptions {
        Some(page_index + 1)
      } else {
        None
      },
    })
  }
}

impl PageContent for InscriptionsBlockHtml {
  fn title(&self) -> String {
    format!("Inscriptions in Block {0}", self.block)
  }
}

#[cfg(test)]
mod tests {
  use super::*;

  #[test]
  fn without_prev_and_next() {
    assert_regex_match!(
      InscriptionsBlockHtml {
        block: 21,
        inscriptions: vec![inscription_id(1), inscription_id(2)],
        prev_block: None,
        next_block: None,
        prev_page: None,
        next_page: None,
      },
      "
        <h1>Inscriptions in <a href=/block/21>Block 21</a></h1>
        <div class=thumbnails>
          <a href=/inscription/1{64}i1><iframe .* src=/preview/1{64}i1></iframe></a>
          <a href=/inscription/2{64}i2><iframe .* src=/preview/2{64}i2></iframe></a>
        </div>
        .*
        prev
        next
        .*
      "