package check

import (
	"slices"
	"strings"
	"testing"

	xhtml "golang.org/x/net/html"

	"amadan.net/rastrillo/fiesta"
	"amadan.net/rastrillo/fiesta/internal/markup"
	"amadan.net/rastrillo/fiesta/internal/rowrule"
)

// The Row Rule: a dropdown never sits on a line of its own. It sits in
// a row beside what it acts on. A menu alone on a line reads as a
// control for nothing in particular, and one above a page's title
// pushes the title down and reads as the page's first action. DESIGN.md
// states the rule, and internal/rowrule is its check, shared with the
// site's landing page. This test holds every example to it, so a
// gallery page can never teach the placement the rule forbids.

// TestEveryDropdownSitsInARow: every state of every example, bodies and
// layouts whole, keeps the Row Rule. The gallery is where a reader
// learns where a menu goes, so a state that shows one alone teaches the
// placement the rule forbids.
func TestEveryDropdownSitsInARow(t *testing.T) {
	states := everyState(t, fiesta.FS())
	menus := 0
	for _, s := range states {
		if strings.Contains(s.Markup, "rst-dropdown") {
			menus++
		}
		respelled, _ := markup.Respell([]byte(s.Markup))
		doc, err := xhtml.Parse(strings.NewReader(string(respelled)))
		if err != nil {
			t.Errorf("%s/%s: the markup does not parse: %v", s.Name, s.State, err)
			continue
		}
		for _, msg := range rowrule.Breaches(doc, nil) {
			t.Errorf("%s/%s: %s", s.Name, s.State, msg)
		}
	}
	// A walk that finds no menus passes whatever the rule says.
	if menus < 10 {
		t.Fatalf("%d states hold a dropdown, want at least 10; the walk is reading the wrong markup", menus)
	}
	if t.Failed() {
		var rows []string
		for row, why := range rowrule.Rows {
			rows = append(rows, row+" ("+why+")")
		}
		slices.Sort(rows)
		t.Logf("put each menu in one of these rows: %s", strings.Join(rows, ", "))
	}
}