package gallery

import (
	"html/template"
	"regexp"
	"strings"
	"testing"

	"amadan.net/rastrillo/fiesta"
)

// The demo application and the modal route as the render writes them:
// four documents in the sidebar shell Fiesta ships, the modal at an
// address of its own, the Overview framing the demo, and nothing else
// in the tree laying a modal over the page it is on. The drives in
// demo_browser_test.go take over where the engine has to answer.

// demoFiles is the demo's four documents, the index first, keyed by
// the view each shows.
var demoFiles = map[string]string{
	"index":     "demo.html",
	"dashboard": "demo-dashboard.html",
	"requests":  "demo-requests.html",
	"request":   "demo-request.html",
}

// demoScripts are the scripts a demo document loads, in order: frame.js
// first, as every document the gallery frames, then the four the spec
// names, which are the layout's own minus the ones the demo has no
// control for.
var demoScripts = []string{"frame.js", "js/fiesta.js", "js/light.js", "js/anchor.js", "js/shell.js"}

// TestTheDemoIsFourDocumentsInTheShippedShell: in every theme and
// locale the demo application is four documents, each the sidebar
// shell the layout examples ship (the index on demo.html, a content
// page on the other three), with the brand Harbour going to the
// demo's own index, a rail of two links with the current one marked
// for the view, the way up to the index at the row just left, Ada
// Lovelace at the foot, the language menu going to the same document
// in each of the twelve locales with this one marked, the view's own
// section and no other, a way back to the design system, the scripts
// the spec names and no others, and no link out of the gallery's own:
// every href in the body is the gallery's or a fragment.
func TestTheDemoIsFourDocumentsInTheShippedShell(t *testing.T) {
	const mount = "/x"
	files := render(t, mount)
	s := newTestSite(t, fiesta.FS(), mount)
	attr := func(n node, name string) string { v, _ := n.attr(name); return v }
	index := parse(t, files["day/en/frames/layout-sidebar/default.html"])
	page := parse(t, files["day/en/frames/layout-sidebar-page/default.html"])
	read := 0
	for _, dir := range dirs() {
		theme, locale, _ := strings.Cut(strings.TrimSuffix(dir, "/"), "/")
		for view, file := range demoFiles {
			name := dir + file
			body, ok := files[name]
			if !ok {
				t.Errorf("the render wrote no %s", name)
				continue
			}
			read++
			doc := parse(t, body)

			// The shell, and its skeleton the layout's own.
			wantShell, layout := "page", page
			if view == "index" {
				wantShell, layout = "index", index
			}
			if m := shellRoot.FindSubmatch(body); m == nil || string(m[1]) != wantShell {
				t.Errorf("%s does not open the sidebar shell as %q", name, wantShell)
			}
			if got, want := shellSkeleton(doc), shellSkeleton(layout); !sameKeys(got, want) {
				t.Errorf("%s: the shell's skeleton %v is not the layout's %v", name, keysOf(got), keysOf(want))
			}

			// The brand, both copies.
			brands := doc.find(byAttr("rst-shell-brand", ""))
			if len(brands) == 0 {
				t.Errorf("%s has no brand", name)
			}
			for _, b := range brands {
				if b.text() != "Harbour" || attr(b, "href") != s.href(theme, locale, "demo.html") || !hasAttr(b, "data-gallery-nav") {
					t.Errorf("%s: the brand reads %q and goes to %q, want Harbour to the demo's index", name, b.text(), attr(b, "href"))
				}
			}

			// The rail: two links, the current one the view's.
			navs := doc.find(func(n node) bool {
				return n.n.Data == "a" && within(n, func(p node) bool { return hasAttr(p, "rst-shell-nav") })
			})
			current := "nav-requests"
			if view == "index" || view == "dashboard" {
				current = "nav-dashboard"
			}
			if len(navs) != 2 {
				t.Errorf("%s: the rail has %d links, want Dashboard and Requests", name, len(navs))
			} else {
				for i, want := range []struct{ id, file string }{{"nav-dashboard", "demo-dashboard.html"}, {"nav-requests", "demo-requests.html"}} {
					a := navs[i]
					if attr(a, "id") != want.id || attr(a, "href") != s.href(theme, locale, want.file) || !hasAttr(a, "data-gallery-nav") {
						t.Errorf("%s: rail link %d is id=%q href=%q, want id=%q href=%q", name, i, attr(a, "id"), attr(a, "href"), want.id, s.href(theme, locale, want.file))
					}
					if mark := attr(a, "aria-current") == "page"; mark != (want.id == current) {
						t.Errorf("%s: %s marked current %v, want %v", name, want.id, mark, want.id == current)
					}
				}
			}

			// The way up: the index itself on the index, and the row
			// just left on a content page.
			up := doc.find(func(n node) bool {
				return n.n.Data == "a" && attr(n, "rel") == "up" && within(n, func(p node) bool { return hasAttr(p, "rst-shell-back") })
			})
			wantUp := s.href(theme, locale, "demo.html")
			if view != "index" {
				wantUp += "#" + current
			}
			if len(up) != 1 || attr(up[0], "href") != wantUp || !hasAttr(up[0], "data-gallery-nav") {
				t.Errorf("%s: %d ways up, want one to %s", name, len(up), wantUp)
			}

			// The person at the foot.
			for _, p := range doc.find(byAttr("rst-person-name", "")) {
				if p.text() != "Ada Lovelace" {
					t.Errorf("%s: the profile names %q, want Ada Lovelace", name, p.text())
				}
			}
			if strings.Contains(string(body), "Grace Hopper") || strings.Contains(string(body), "Party planner") {
				t.Errorf("%s still carries the layout's own person or brand", name)
			}

			// The language menu: the same document in every locale.
			langs := doc.find(func(n node) bool {
				return n.n.Data == "a" && within(n, func(p node) bool { return hasAttr(p, "rst-locale") })
			})
			if len(langs) != len(Locales) {
				t.Errorf("%s: %d language links, want %d", name, len(langs), len(Locales))
			}
			for _, a := range langs {
				lang := attr(a, "lang")
				if attr(a, "href") != s.href(theme, lang, file) || !hasAttr(a, "data-gallery-nav") {
					t.Errorf("%s: the %s link goes to %q, want %q", name, lang, attr(a, "href"), s.href(theme, lang, file))
				}
				if mark := attr(a, "aria-current") == "true"; mark != (lang == locale) {
					t.Errorf("%s: the %s link marked current %v", name, lang, mark)
				}
			}

			// The view, alone.
			wantView := "view-" + view
			if view == "index" {
				wantView = "view-dashboard"
			}
			views := doc.find(byClass("app-view"))
			if len(views) != 1 || attr(views[0], "id") != wantView {
				var ids []string
				for _, v := range views {
					ids = append(ids, attr(v, "id"))
				}
				t.Errorf("%s shows the views %v, want exactly %s", name, ids, wantView)
			}

			// The way back to the design system.
			back := s.say(locale, "gallery.back")
			found := false
			for _, a := range bodyLinks(t, doc) {
				if a.text() == back && attr(a, "href") == s.href(theme, locale, "index.html") && hasAttr(a, "data-gallery-nav") {
					found = true
				}
			}
			if !found {
				t.Errorf("%s has no %q link to the Overview", name, back)
			}

			// The scripts.
			var scripts []string
			for _, sc := range doc.find(func(n node) bool { return n.n.Data == "script" }) {
				scripts = append(scripts, attr(sc, "src"))
			}
			var want []string
			for _, sc := range demoScripts {
				want = append(want, s.asset(sc))
			}
			if strings.Join(scripts, " ") != strings.Join(want, " ") {
				t.Errorf("%s loads %v, want %v", name, scripts, want)
			}

			// Nothing leaves the gallery.
			for _, a := range bodyLinks(t, doc) {
				h := attr(a, "href")
				if !strings.HasPrefix(h, "#") && !(hasAttr(a, "data-gallery-nav") && strings.HasPrefix(h, mount+"/")) {
					t.Errorf("%s: %q goes to %q, neither the gallery's nor a fragment", name, a.text(), h)
				}
			}
		}
	}
	if read != len(dirs())*len(demoFiles) {
		t.Fatalf("read %d demo documents, want %d", read, len(dirs())*len(demoFiles))
	}
}

// sameKeys says whether two sets hold the same keys.
func sameKeys(a, b map[string]bool) bool {
	if len(a) != len(b) {
		return false
	}
	for k := range a {
		if !b[k] {
			return false
		}
	}
	return true
}

// keysOf is a set's keys, for a message.
func keysOf(m map[string]bool) []string {
	var out []string
	for k := range m {
		out = append(out, k)
	}
	return out
}

// liveOverlay is a modal laid out live: the overlay or the backdrop as
// an element, never as escaped source in a code block.
var liveOverlay = regexp.MustCompile(`<div rst-(modal-overlay|backdrop)\b`)

// TestNoGalleryPageOpensAModalOverTheGallery: no document under a theme
// and locale lays a modal over itself but the modal route's own,
// demo-modal.html (the frames are documents of their own, framed, and
// excluded); the modal example's page shows the overlay as source and
// links the route in a new tab; and on the route itself the panel's
// tabs link the route, Close and the back button go to the Overview,
// and the backdrop holds a page that is inert.
func TestNoGalleryPageOpensAModalOverTheGallery(t *testing.T) {
	const mount = "/x"
	files := render(t, mount)
	s := newTestSite(t, fiesta.FS(), mount)
	attr := func(n node, name string) string { v, _ := n.attr(name); return v }
	routes := 0
	for name, body := range files {
		if !strings.HasSuffix(name, ".html") || isFrame(name) || strings.HasSuffix(name, "/demo-modal.html") {
			continue
		}
		if m := liveOverlay.Find(body); m != nil {
			t.Errorf("%s lays out a live %s over the page", name, m)
		}
	}
	for _, dir := range dirs() {
		theme, locale, _ := strings.Cut(strings.TrimSuffix(dir, "/"), "/")
		self := s.href(theme, locale, "demo-modal.html")
		overview := s.href(theme, locale, "index.html")

		page := examplePage(t, files, theme, locale, "modal")
		if !strings.Contains(strings.Join(sourceTexts(page), "\n"), `<div rst-modal-overlay>`) {
			t.Errorf("%smodal.html does not show the overlay as source", dir)
		}
		link := regexp.MustCompile(`<a data-gallery-nav href="` + regexp.QuoteMeta(self) + `" target="_blank" rel="noopener">`)
		if !link.MatchString(page) {
			t.Errorf("%smodal.html does not link %s in a new tab", dir, self)
		}

		name := dir + "demo-modal.html"
		body, ok := files[name]
		if !ok {
			t.Errorf("the render wrote no %s", name)
			continue
		}
		routes++
		doc := parse(t, body)
		if n := len(liveOverlay.FindAll(body, -1)); n != 2 {
			t.Errorf("%s lays out %d of the backdrop and the overlay, want both", name, n)
		}
		backdrop, ok := doc.first(byAttr("rst-backdrop", ""))
		if !ok || !hasAttr(backdrop, "inert") {
			t.Errorf("%s: the backdrop is missing or not inert", name)
		} else {
			if h, ok := backdrop.first(func(n node) bool { return n.n.Data == "h1" }); !ok || h.text() != s.say(locale, "gallery.modal.settings") {
				t.Errorf("%s: the page under the modal has no heading %q", name, s.say(locale, "gallery.modal.settings"))
			}
			if !strings.Contains(backdrop.text(), s.say(locale, "gallery.modal.own")) {
				t.Errorf("%s: the page under the modal does not say %q", name, s.say(locale, "gallery.modal.own"))
			}
		}
		panel, ok := doc.first(byAttr("rst-modal-panel", ""))
		if !ok {
			t.Errorf("%s has no panel", name)
			continue
		}
		tabs := panel.find(func(n node) bool {
			return n.n.Data == "a" && within(n, func(p node) bool { return p.n.Data == "nav" })
		})
		if len(tabs) != 3 {
			t.Errorf("%s: the panel has %d tabs, want 3", name, len(tabs))
		}
		for i, a := range tabs {
			if attr(a, "href") != self || !hasAttr(a, "data-gallery-nav") {
				t.Errorf("%s: tab %q goes to %q, want the route itself", name, a.text(), attr(a, "href"))
			}
			if mark := attr(a, "aria-current") == "page"; mark != (i == 0) {
				t.Errorf("%s: tab %q marked current %v", name, a.text(), mark)
			}
		}
		closers := panel.find(byAttr("rst-modal-close", ""))
		if len(closers) != 1 || attr(closers[0], "href") != overview || attr(closers[0], "aria-label") != s.say(locale, "gallery.modal.close") {
			t.Errorf("%s: Close does not go to the Overview under its name", name)
		}
		back := false
		for _, a := range panel.find(func(n node) bool { return n.n.Data == "a" }) {
			if a.text() == s.say(locale, "gallery.back") && attr(a, "href") == overview && hasAttr(a, "data-gallery-nav") {
				back = true
			}
		}
		if !back {
			t.Errorf("%s: the panel has no %q button to the Overview", name, s.say(locale, "gallery.back"))
		}
		for _, id := range []string{"gallery.modal.body", "gallery.modal.nojs", "gallery.modal.inapp"} {
			if !strings.Contains(panel.text(), squash(s.say(locale, id))) {
				t.Errorf("%s: the panel does not say %q", name, s.say(locale, id))
			}
		}
	}
	if routes != len(dirs()) {
		t.Fatalf("read %d modal routes, want %d", routes, len(dirs()))
	}
}

// TestTheOverviewFramesTheDemo: every Overview frames the demo
// application between its intro and its routes: the heading and its
// lead, one widget at the page width with Desktop and Mobile and no
// HTML tab (an application is not a snippet to paste), at the demo's
// heights, framing its own directory's demo.html, and the link that
// opens it in a new tab and says so.
func TestTheOverviewFramesTheDemo(t *testing.T) {
	const mount = "/x"
	files := render(t, mount)
	s := newTestSite(t, fiesta.FS(), mount)
	for _, dir := range dirs() {
		theme, locale, _ := strings.Cut(strings.TrimSuffix(dir, "/"), "/")
		name := dir + "index.html"
		page := string(files[name])
		section := regexp.MustCompile(`(?s)<section class="ds-demo" id="demo-app">(.*?)</section>`).FindStringSubmatch(page)
		if section == nil {
			t.Errorf("%s frames no demo", name)
			continue
		}
		intro, demo, next := strings.Index(page, `class="ds-intro"`), strings.Index(page, `class="ds-demo"`), strings.Index(page, `class="ds-routes"`)
		if !(intro >= 0 && intro < demo && demo < next) {
			t.Errorf("%s: the demo is not between the intro and the routes", name)
		}
		body := section[1]
		for _, id := range []string{"gallery.demo.heading", "gallery.demo.lead"} {
			if !strings.Contains(body, template.HTMLEscapeString(s.say(locale, id))) {
				t.Errorf("%s: the demo section does not say %q", name, s.say(locale, id))
			}
		}
		widgets := widgetsOf(body)
		if len(widgets) != 1 {
			t.Errorf("%s: %d widgets in the demo section, want 1", name, len(widgets))
			continue
		}
		w := widgets[0]
		if _, ok := previewHeights["demo"]; !ok {
			t.Fatal("heights.go has no measured height for the demo")
		}
		if !strings.Contains(body, `<div class="ds-view ds-view--page" style="`+string(previewStyle(locale, "demo"))) {
			t.Errorf("%s: the demo's widget is not at the page width and the demo's heights (%s)", name, previewStyle(locale, "demo"))
		}
		var order string
		for _, m := range tabClass.FindAllStringSubmatch(w, -1) {
			order += m[1]
		}
		if order != "dm" || panelOf(w) != "" {
			t.Errorf("%s: the demo's tabs are %q with panel %v, want Desktop and Mobile and no HTML", name, order, panelOf(w) != "")
		}
		src := `src="` + s.href(theme, locale, "demo.html") + `"`
		if strings.Count(w, `<iframe class="ds-view__frame"`) != 1 || !strings.Contains(w, src) {
			t.Errorf("%s: the widget does not frame %s", name, src)
		}
		open := `<a data-gallery-nav href="` + s.href(theme, locale, "demo.html") + `" target="_blank" rel="noopener">` +
			template.HTMLEscapeString(s.say(locale, "gallery.demo.open")) +
			`<span class="rst-sr-only"> (` + template.HTMLEscapeString(s.say(locale, "gallery.newtab")) + `)</span></a>`
		if !strings.Contains(body, open) {
			t.Errorf("%s: no link opens the demo in a new tab saying so", name)
		}
	}
}