{{- $image := "" -}}
{{- if .IsHome -}}
  {{- $image = "/images/social/github.png" -}}
{{- else -}}
  {{- with .Params.social_image -}}
    {{- $image = . -}}
  {{- else with .File -}}
    {{- $stem := replaceRE "\\.md$" "" .Path -}}
    {{- $stem = replaceRE "/_index$" "" $stem -}}
    {{- if or (eq $stem "") (eq $stem "_index") -}}
      {{- $stem = "index" -}}
    {{- end -}}
    {{- $image = printf "/images/social/%s.png" $stem -}}
  {{- end -}}
{{- end -}}
{{- with $image -}}{{ . | absURL }}{{- end -}}