package stacks

import "regexp"

// reDomainPlaceholder matches the catalog's address placeholder in app copy: a bare `DOMAIN` or a
// `<label>.DOMAIN` (wiki.DOMAIN, https://paste.DOMAIN/…). `\b` keeps SUBDOMAIN and MAIL_DOMAIN out —
// the letter or underscore before them is a word character, so no boundary falls inside them.
var reDomainPlaceholder = regexp.MustCompile(`(?:([a-z0-9-]+)\.)?\bDOMAIN\b`)

// WithAddress returns a copy of the app copy with the catalog's `DOMAIN` placeholder filled in
// (R-498): `<label>.DOMAIN` becomes `<subdomain>.<domain>` — the app's EFFECTIVE subdomain (the one
// the household chose at install), or the catalog label when none is known — and a bare `DOMAIN`
// becomes `<domain>`. With no domain configured the copy is returned unchanged: a placeholder is
// better than an address that is wrong. The receiver is not modified (slices are copied), because the
// stack's metadata is shared with every other page. Pinned by TestR498_* (stacks and web).
func (ai AppInfo) WithAddress(subdomain, domain string) AppInfo {
	if domain == "" {
		return ai
	}
	fill := func(s string) string {
		return reDomainPlaceholder.ReplaceAllStringFunc(s, func(m string) string {
			sub := reDomainPlaceholder.FindStringSubmatch(m)
			if sub[1] == "" {
				return domain
			}
			label := sub[1]
			if subdomain != "" {
				label = subdomain
			}
			return label + "." + domain
		})
	}
	list := func(in []string) []string {
		if in == nil {
			return nil
		}
		out := make([]string, len(in))
		for i, s := range in {
			out[i] = fill(s)
		}
		return out
	}
	out := ai
	out.Tagline = fill(ai.Tagline)
	out.UseCases = list(ai.UseCases)
	out.FirstSteps = list(ai.FirstSteps)
	out.Prerequisites = list(ai.Prerequisites)
	out.DefaultCreds = fill(ai.DefaultCreds)
	out.AddPeople = fill(ai.AddPeople)
	return out
}