package docs

import "time"

var (
	adrStatuses = []string{"proposed", "accepted", "rejected", "deprecated", "superseded"}
	adrImpls    = []string{"not-started", "in-progress", "implemented", "deferred", "not-applicable"}
	adrRefs     = []refSpec{
		{"supersedes", kAdr}, {"superseded_by", kAdr}, {"related", kAdr | kPlan},
		{"tracking", kPlan | kURL}, {"implemented_by", kURL | kFile},
	}
)

// adr checks the ADR frontmatter and returns its title for the body check.
func (c *checker) adr(r *record, m *fm) (string, bool) {
	m.keys("title", "date", "status", "implementation", "summary", "tags", "supersedes", "superseded_by", "related", "tracking", "implemented_by")
	title, titleOK := m.text("title")
	if d, line, ok := m.scalar("date"); ok {
		if _, err := time.Parse(time.DateOnly, d); err != nil || len(d) != len(time.DateOnly) {
			c.add(r.path, line, "date must be a valid YYYY-MM-DD date")
		} else if d != r.date {
			c.add(r.path, line, "date %s does not match the filename date %s", d, r.date)
		}
	}
	status, statusOK := m.enum("status", adrStatuses...)
	impl, implOK := m.enum("implementation", adrImpls...)
	m.text("summary")
	m.tags()
	m.refs(adrRefs...)
	r.status = status
	if statusOK {
		if n := len(r.lists["superseded_by"]); status == "superseded" && n == 0 {
			m.problemf("status", "status superseded requires superseded_by")
		} else if status != "superseded" && n > 0 {
			m.problemf("superseded_by", "superseded_by requires status superseded")
		}
		if status == "rejected" && implOK && impl != "not-applicable" {
			m.problemf("implementation", "status rejected requires implementation not-applicable")
		}
	}
	if implOK && impl == "implemented" && len(r.lists["implemented_by"]) == 0 {
		m.problemf("implementation", "implementation implemented requires implemented_by")
	}
	return title, titleOK
}