{% extends "base.html" %}

{% macro page_title() -%}
  {%- if page.is_homepage -%}
    {{ config.site_name }} - {{ config.site_description }}
  {%- elif page.meta and page.meta.title -%}
    {{ page.meta.title }} - {{ config.site_name }}
  {%- elif page.toc and page.toc.items and page.toc.items[0].level == 1 -%}
    {{ page.toc.items[0].title | striptags }} - {{ config.site_name }}
  {%- elif page.title -%}
    {{ page.title | striptags }} - {{ config.site_name }}
  {%- else -%}
    {{ config.site_name }}
  {%- endif -%}
{%- endmacro %}

{% block htmltitle %}
  <title>{{ page_title() | striptags | e }}</title>
{% endblock %}

{% block extrahead %}
  {% set description = page.meta.description if page.meta and page.meta.description else config.site_description %}
  {% set image = config.site_url ~ "assets/social-preview.png" %}
  {% set image_alt = "The Narwhal logo, a black narwhal with a teal spiral tusk above the wordmark" %}
  <meta property="og:type" content="website">
  <meta property="og:site_name" content="{{ config.site_name }}">
  <meta property="og:title" content="{{ page_title() | striptags | e }}">
  <meta property="og:description" content="{{ description | e }}">
  {% if page.canonical_url %}
    <meta property="og:url" content="{{ page.canonical_url }}">
  {% endif %}
  <meta property="og:image" content="{{ image }}">
  <meta property="og:image:width" content="1280">
  <meta property="og:image:height" content="640">
  <meta property="og:image:alt" content="{{ image_alt }}">
  <meta name="twitter:card" content="summary_large_image">
  <meta name="twitter:title" content="{{ page_title() | striptags | e }}">
  <meta name="twitter:description" content="{{ description | e }}">
  <meta name="twitter:image" content="{{ image }}">
  <meta name="twitter:image:alt" content="{{ image_alt }}">
{% endblock %}