providers: Add import/include provider

providers/import/import.go

@@ -0,0 +1,46 @@
+package impor
+
+import "strings"
+import "html/template"
+import "git.tebibyte.media/sashakoshka/step"
+
+var _ step.FuncProviderFor = new(Provider)
+
+// Provider provides import functions.
+type Provider struct {
+	
+}
+
+// FuncMap fulfills the step.FuncProvider interface.
+func (this *Provider) FuncMap () template.FuncMap {
+	return nil
+}
+
+// FuncMapFor fulfills the step.FuncProviderFor interface.
+func (this *Provider) FuncMapFor (document *step.Document) template.FuncMap {
+	stat := &state {
+		document: document,
+	}
+	return template.FuncMap {
+		"include":     stat.funcInclude,
+		"includeHTML": stat.funcIncludeHTML,
+	}
+}
+
+type state struct {
+	document *step.Document
+}
+
+func (this *state) funcInclude (name string, data any) (string, error) {
+	document, err := this.document.Environment().Parse(name)
+	if err != nil { return "", err }
+	builder := strings.Builder { }
+	err = document.Execute(&builder, step.ExecutionData { Data: data })
+	if err != nil { return "", err }
+	return builder.String(), nil
+}
+
+func (this *state) funcIncludeHTML (name string, data any) (template.HTML, error) {
+	result, err := this.funcInclude(name, data)
+	return template.HTML(result), err
+}