feat: youtube widget macro (#127)

README.md

@@ -197,6 +197,13 @@ By default, mark provides several built-in templates and macros:
 
   See: https://confluence.atlassian.com/doc/confluence-storage-format-790796544.html
 
+* template: `ac:youtube` to include YouTube Widget. Parameters:
+  - URL: YouTube video endpoint
+  - Width: Width in px. Defualts to "640px"
+  - Height: Height in px. Defualts to "360px"
+
+  See: https://confluence.atlassian.com/doc/widget-connector-macro-171180449.html#WidgetConnectorMacro-YouTube
+
 * macro `@{...}` to mention user by name specified in the braces.
 
 ## Template & Macros Usecases

pkg/mark/stdlib/stdlib.go

@@ -177,6 +177,18 @@ func templates(api *confluence.API) (*template.Template, error) {
 			`<ac:emoticon ac:name="{{ .Name }}"/>`,
 		),
 
+		/* https://confluence.atlassian.com/doc/widget-connector-macro-171180449.html#WidgetConnectorMacro-YouTube */
+
+		`ac:youtube`: text(
+			`<ac:structured-macro ac:name="widget">{{printf "\n"}}`,
+			`<ac:parameter ac:name="overlay">youtube</ac:parameter>{{printf "\n"}}`,
+			`<ac:parameter ac:name="_template">com/atlassian/confluence/extra/widgetconnector/templates/youtube.vm</ac:parameter>{{printf "\n"}}`,
+			`<ac:parameter ac:name="width">{{ or .Width "640px" }}</ac:parameter>{{printf "\n"}}`,
+			`<ac:parameter ac:name="height">{{ or .Height "360px" }}</ac:parameter>{{printf "\n"}}`,
+			`<ac:parameter ac:name="url"><ri:url ri:value="{{ .URL }}" /></ac:parameter>{{printf "\n"}}`,
+			`</ac:structured-macro>{{printf "\n"}}`,
+		),
+
 		// TODO(seletskiy): more templates here
 	} {
 		templates, err = templates.New(name).Parse(body)