package template

import (
	"regexp"
	"strings"
)

var unresolvedPlaceholderPattern = regexp.MustCompile(`\{\{[a-zA-Z0-9_]+\}\}`)

func RenderDoc(tmpl string, vars map[string]string) string {
	res := tmpl
	for k, v := range vars {
		placeholder := "{{" + k + "}}"
		res = strings.ReplaceAll(res, placeholder, v)
	}
	// Any variable that wasn't provided leaves a raw {{placeholder}} in the
	// output. Replace those with a clear "待确认" marker instead of leaking
	// template syntax into delivered documents.
	res = unresolvedPlaceholderPattern.ReplaceAllString(res, "待确认")
	return res
}