package shortcodes

import (
	"strings"
	"testing"
	"testing/fstest"

	"github.com/yuin/goldmark"

	"khosra/internal/content"
	"khosra/internal/render"
)

func TestParseAcceptsOnlyAWholeLineCall(t *testing.T) {
	name, args, ok := parse(`  {{< figure src="a.jpg" alt="A cat" >}}  `)
	if !ok || name != "figure" {
		t.Fatalf("parse gave %q %v ok=%v", name, args, ok)
	}
	if args["src"] != "a.jpg" || args["alt"] != "A cat" {
		t.Errorf("args = %v", args)
	}
	if _, _, ok := parse(`{{< figure src="a.jpg" >}} and then prose`); ok {
		t.Error("a call must be the whole line, so trailing prose is not a call")
	}
	for _, line := range []string{
		"plain prose",
		"{{< figure",                   // unterminated
		`{{< src="a.jpg" >}}`,          // no name
		`{{< figure src=a.jpg >}}`,     // unquoted value
		`{{< figure src="unclosed >}}`, // unbalanced quote
		"{{<>}}",                       // empty
	} {
		if _, _, ok := parse(line); ok {
			t.Errorf("parse accepted %q", line)
		}
	}
}

// wired builds a real Renderer wired to this extension, the way cmd does.
func wired(t *testing.T, siteFS fstest.MapFS) *render.Renderer {
	t.Helper()
	var fsys fstest.MapFS
	if siteFS != nil {
		fsys = siteFS
	}
	r, err := render.New(fsys, content.Settings{}, func(p render.Partial) []goldmark.Extender {
		return []goldmark.Extender{New(p)}
	})
	if err != nil {
		t.Fatal(err)
	}
	return r
}

func body(t *testing.T, r *render.Renderer, markdown string) string {
	t.Helper()
	b, err := content.Parse("posts/x.md", []byte("---\ntitle: X\n---\n"+markdown))
	if err != nil {
		t.Fatal(err)
	}
	out, err := r.Bundle(b, "en", nil, nil)
	if err != nil {
		t.Fatal(err)
	}
	return string(out)
}

func TestFigureRendersThroughTheThemeFragment(t *testing.T) {
	got := body(t, wired(t, nil), "Before.\n\n{{< figure src=\"cat.jpg\" alt=\"A cat\" caption=\"Sleeping\" >}}\n\nAfter.\n")
	for _, want := range []string{
		"<figure>", `<img src="cat.jpg" alt="A cat">`, "<figcaption>Sleeping</figcaption>", "</figure>",
	} {
		if !strings.Contains(got, want) {
			t.Errorf("missing %q:\n%s", want, got)
		}
	}
	if strings.Contains(got, "<p><figure>") || strings.Contains(got, "{{<") {
		t.Errorf("a call on its own line is a block, not paragraph text:\n%s", got)
	}
}

func TestAnAuthorsArgumentCannotBecomeMarkup(t *testing.T) {
	// The security property of ADR-0036, on a call that really parses: output is a template's, so hostile
	// argument text arrives as escaped data in whichever context it lands in.
	got := body(t, wired(t, nil), `{{< figure src="ok.jpg" alt="<script>alert(1)</script>" >}}`+"\n")
	if strings.Contains(got, "<script>") {
		t.Fatalf("an argument became markup:\n%s", got)
	}
	if !strings.Contains(got, "&lt;script&gt;") {
		t.Errorf("the hostile alt text should survive as escaped text:\n%s", got)
	}

	// A javascript: URL in an attribute the template uses as a URL is html/template's job, and getting it
	// for free is the reason a fragment renders this rather than the feature (ADR-0036).
	got = body(t, wired(t, nil), `{{< figure src="javascript:alert(1)" alt="x" >}}`+"\n")
	if strings.Contains(got, "javascript:alert(1)") {
		t.Errorf("a javascript: URL should not survive into src:\n%s", got)
	}

	// A quote cannot even be expressed in an argument, so attribute breakout fails at the syntax before it
	// reaches escaping: the call is not a call, and the line stays prose.
	got = body(t, wired(t, nil), `{{< figure src="x.jpg\" onerror=\"alert(1)" >}}`+"\n\n<script>alert(2)</script>\n")
	if strings.Contains(got, "onerror") && !strings.Contains(got, "&quot;") {
		t.Errorf("a malformed call must stay escaped text, not markup:\n%s", got)
	}
	if !strings.Contains(got, "raw HTML omitted") {
		t.Errorf("authored raw HTML must still be dropped:\n%s", got)
	}
}

func TestAnUnknownShortcodeDegradesToNothing(t *testing.T) {
	got := body(t, wired(t, nil), "{{< nosuchthing key=\"v\" >}}\n\nStill here.\n")
	if !strings.Contains(got, "Still here.") {
		t.Errorf("the rest of the page must survive:\n%s", got)
	}
	if strings.Contains(got, "nosuchthing") {
		t.Errorf("a missing fragment renders nothing, not its own name:\n%s", got)
	}
}

// galleryFS is a directory bundle with pictures, a non-picture, and a subdirectory that is not one.
func galleryFS() fstest.MapFS {
	return fstest.MapFS{
		"content/art/monsoon/index.md":       {Data: []byte("---\ntitle: Monsoon\n---\n{{< gallery >}}\n")},
		"content/art/monsoon/20-second.jpg":  {Data: []byte("x")},
		"content/art/monsoon/10-first.PNG":   {Data: []byte("x")},
		"content/art/monsoon/30-third.webp":  {Data: []byte("x")},
		"content/art/monsoon/notes.md":       {Data: []byte("not a picture")},
		"content/art/monsoon/sketches/a.jpg": {Data: []byte("x")},
		"content/art/elsewhere.jpg":          {Data: []byte("x")},
	}
}

// bundle renders the named bundle out of fsys, the way the server does.
func bundle(t *testing.T, fsys fstest.MapFS, name string) string {
	t.Helper()
	bundles, err := content.Scan(fsys)
	if err != nil {
		t.Fatal(err)
	}
	site := content.NewSite(bundles)
	b, served, ok := site.Lookup(name, "en")
	if !ok {
		t.Fatalf("no bundle %q", name)
	}
	out, err := wired(t, fsys).Bundle(b, served, nil, nil)
	if err != nil {
		t.Fatal(err)
	}
	return string(out)
}

func TestGalleryListsThePicturesBesideItsBundle(t *testing.T) {
	got := bundle(t, galleryFS(), "art/monsoon")
	first := strings.Index(got, "10-first.PNG")
	second := strings.Index(got, "20-second.jpg")
	third := strings.Index(got, "30-third.webp")
	if first < 0 || second < first || third < second {
		t.Errorf("pictures should list in filename order, case-insensitively recognised:\n%s", got)
	}
	for _, absent := range []string{"notes.md", "sketches", "elsewhere.jpg"} {
		if strings.Contains(got, absent) {
			t.Errorf("a gallery is pictures beside the bundle only, but %q appeared:\n%s", absent, got)
		}
	}
}

func TestGalleryWithoutASiteRootRendersNothing(t *testing.T) {
	// wired(t, nil) has no files, which is how a unit test or a bare renderer is built. Gathering nothing
	// must not become a broken page.
	got := body(t, wired(t, nil), "{{< gallery >}}\n\nStill here.\n")
	if !strings.Contains(got, "Still here.") {
		t.Errorf("the page must survive a gallery with nothing to show:\n%s", got)
	}
	if strings.Contains(got, "<div class=\"gallery\">") {
		t.Errorf("an empty gallery should render nothing at all:\n%s", got)
	}
}

func TestIncludeRendersTheFileBesideTheBundle(t *testing.T) {
	fsys := fstest.MapFS{
		"content/pages/about/index.md": {Data: []byte("---\ntitle: About\n---\nFirst.\n\n{{< include file=\"more.md\" >}}\n\nLast.\n")},
		"content/pages/about/more.md":  {Data: []byte("## Included\n\nWith *emphasis* and a [link](/posts/).\n")},
	}
	got := bundle(t, fsys, "pages/about")
	// Converted as Markdown, not pasted as text: the heading, emphasis and link prove it.
	for _, want := range []string{"<h2>Included</h2>", "<em>emphasis</em>", `href="/posts/"`} {
		if !strings.Contains(got, want) {
			t.Errorf("missing %q — an include is Markdown, not a string:\n%s", want, got)
		}
	}
	first, included, last := strings.Index(got, "First."), strings.Index(got, "Included"), strings.Index(got, "Last.")
	if first < 0 || included < first || last < included {
		t.Errorf("included content belongs where the call was:\n%s", got)
	}
}

func TestAnIncludedFileCannotItselfInclude(t *testing.T) {
	// One level, by design (ADR-0038). A file including itself is the case that would otherwise recurse
	// until the stack gave out — a crash caused by content, which ADR-0029 forbids.
	fsys := fstest.MapFS{
		"content/pages/loop/index.md": {Data: []byte("---\ntitle: Loop\n---\nBefore.\n\n{{< include file=\"self.md\" >}}\n\nAfter.\n")},
		"content/pages/loop/self.md":  {Data: []byte("Round.\n\n{{< include file=\"self.md\" >}}\n")},
	}
	got := bundle(t, fsys, "pages/loop")
	for _, want := range []string{"Before.", "Round.", "After."} {
		if !strings.Contains(got, want) {
			t.Errorf("missing %q — one level must still render:\n%s", want, got)
		}
	}
	if n := strings.Count(got, "Round."); n != 1 {
		t.Errorf("expanded %d times, want exactly one level", n)
	}
	if strings.Contains(got, "{{<") {
		t.Errorf("the ignored nested call renders nothing, it is not printed:\n%s", got)
	}
}

func TestAGalleryInsideAnIncludedFileStillResolves(t *testing.T) {
	// The nested parse carries the same Origin, which is what makes this work.
	fsys := fstest.MapFS{
		"content/art/set/index.md": {Data: []byte("---\ntitle: Set\n---\n{{< include file=\"body.md\" >}}\n")},
		"content/art/set/body.md":  {Data: []byte("Studies:\n\n{{< gallery >}}\n")},
		"content/art/set/one.jpg":  {Data: []byte("x")},
		"content/art/set/two.png":  {Data: []byte("x")},
	}
	got := bundle(t, fsys, "art/set")
	if !strings.Contains(got, "one.jpg") || !strings.Contains(got, "two.png") {
		t.Errorf("a gallery inside an include should resolve against the same bundle:\n%s", got)
	}
}

func TestIncludeCannotEscapeTheSiteRootAndDegradesOnMisses(t *testing.T) {
	fsys := fstest.MapFS{
		// `..` is refused outright: path.Join would collapse it to a real path inside the site root, which
		// would let an include publish a template or a dotfile that is not content (ADR-0038).
		"content/pages/a/index.md": {Data: []byte("---\ntitle: A\n---\n{{< include file=\"../../../etc/passwd\" >}}\n\nSurvived.\n")},
		"content/pages/d/index.md": {Data: []byte("---\ntitle: D\n---\n{{< include file=\"../../../secret.md\" >}}\n\nSurvived.\n")},
		"secret.md":                {Data: []byte("NOT CONTENT\n")},
		"content/pages/b/index.md": {Data: []byte("---\ntitle: B\n---\n{{< include file=\"nothing.md\" >}}\n\nSurvived.\n")},
		"content/pages/c/index.md": {Data: []byte("---\ntitle: C\n---\n{{< include >}}\n\nSurvived.\n")},
	}
	for _, key := range []string{"pages/a", "pages/b", "pages/c", "pages/d"} {
		got := bundle(t, fsys, key)
		if !strings.Contains(got, "Survived.") {
			t.Errorf("%s: the page must survive a bad include:\n%s", key, got)
		}
		if strings.Contains(got, "root:") || strings.Contains(got, "passwd") || strings.Contains(got, "NOT CONTENT") {
			t.Fatalf("%s: an include read something it must not:\n%s", key, got)
		}
	}
}

func TestASiteRedefinesOneFragment(t *testing.T) {
	site := fstest.MapFS{
		"templates/shortcodes.html": {Data: []byte(`{{define "figure"}}<div class="mine">{{.Args.src}}</div>{{end}}`)},
	}
	got := body(t, wired(t, site), "{{< figure src=\"cat.jpg\" >}}\n")
	if !strings.Contains(got, `<div class="mine">cat.jpg</div>`) {
		t.Errorf("the site's fragment should win:\n%s", got)
	}
	if strings.Contains(got, "<figure>") {
		t.Error("the embedded fragment should have been replaced, not appended")
	}
}