package postcard

import (
	"context"
	"strings"
	"testing"
	"testing/fstest"
)

func TestMailRecipientsAndSafety(t *testing.T) {
	t.Parallel()

	fsys := fstest.MapFS{
		"views/mail/hello.htm": {Data: []byte(`subject = "Witaj {{ .Name }}"
layout = "default"
==
Witaj **{{ .Name }}**.

[Strona]({{ .URL }})
`)},
	}
	cat := NewCatalog()
	if err := cat.Register("golem15.hello", fsys, []string{"golem15.hello::mail.hello"}, nil); err != nil {
		t.Fatal(err)
	}
	drv := NewMemoryDriver()
	mail := NewMailer(cat, drv, Options{From: "from@example.test"})
	ctx := context.Background()

	if err := mail.Send(ctx, Message{
		Template: "golem15.hello::mail.hello",
		To:       []string{"ada@example.test"},
		Cc:       []string{"cc@example.test"},
		Bcc:      []string{"bcc@example.test"},
		ReplyTo:  "reply@example.test",
		Vars:     map[string]any{"Name": "Ada", "URL": "https://example.test"},
	}); err != nil {
		t.Fatal(err)
	}
	got := drv.Messages()
	if len(got) != 1 {
		t.Fatalf("stored %d messages", len(got))
	}
	msg := got[0]
	if len(msg.To) != 1 || msg.To[0] != "ada@example.test" {
		t.Fatalf("To = %v", msg.To)
	}
	if len(msg.Cc) != 1 || msg.Cc[0] != "cc@example.test" {
		t.Fatalf("Cc = %v", msg.Cc)
	}
	if len(msg.Bcc) != 1 || msg.Bcc[0] != "bcc@example.test" {
		t.Fatalf("Bcc = %v", msg.Bcc)
	}
	if msg.ReplyTo != "reply@example.test" {
		t.Fatalf("ReplyTo = %q", msg.ReplyTo)
	}
	if msg.Subject != "Witaj Ada" {
		t.Fatalf("subject = %q", msg.Subject)
	}
	if !strings.Contains(msg.Text, "Witaj **Ada**.") {
		t.Fatalf("text = %q", msg.Text)
	}
	if !strings.Contains(msg.HTML, "<strong>Ada</strong>") || !strings.Contains(msg.HTML, `href="https://example.test"`) {
		t.Fatalf("html = %q", msg.HTML)
	}

	t.Run("raw tags markdown links and dangerous urls stay out of html", func(t *testing.T) {
		cases := []map[string]any{
			{"Name": `<script>alert(1)</script>`, "URL": "https://example.test"},
			{"Name": "Ada", "URL": "javascript:alert(1)"},
			{"Name": "Ada", "URL": "vbscript:msgbox(1)"},
			{"Name": "Ada", "URL": "data:text/html;base64,PGh0bWw+"},
			{"Name": `<iframe src="https://evil.test"></iframe>`, "URL": "https://example.test"},
		}
		for _, vars := range cases {
			drv := NewMemoryDriver()
			mail := NewMailer(cat, drv, Options{From: "from@example.test"})
			err := mail.Send(ctx, Message{
				Template: "golem15.hello::mail.hello",
				To:       []string{"ada@example.test"},
				Vars:     vars,
			})
			if err != nil {
				if strings.Contains(err.Error(), "unsafe") || strings.Contains(err.Error(), "dangerous") {
					continue
				}
				t.Fatalf("unexpected send error for %v: %v", vars, err)
			}
			html := strings.ToLower(drv.Messages()[0].HTML)
			for _, banned := range []string{"<script", "<iframe", "javascript:", "vbscript:", "data:text/html"} {
				if strings.Contains(html, banned) {
					t.Fatalf("unsafe %q leaked for %v:\n%s", banned, vars, html)
				}
			}
		}
	})
}

func TestMailRegistrationBoundaries(t *testing.T) {
	t.Parallel()

	t.Run("reserved default alias", func(t *testing.T) {
		err := NewCatalog().Register("golem15.hello", fstest.MapFS{}, nil, map[string]string{
			"default": "golem15.hello::mail.layouts.default",
		})
		if err == nil || !strings.Contains(err.Error(), "reserved") {
			t.Fatalf("reserved alias error = %v", err)
		}
	})
	t.Run("template not owned by plugin", func(t *testing.T) {
		err := NewCatalog().Register("golem15.hello", fstest.MapFS{}, []string{"golem15.other::mail.hello"}, nil)
		if err == nil || !strings.Contains(err.Error(), "golem15.hello") || !strings.Contains(err.Error(), "golem15.other::mail.hello") {
			t.Fatalf("ownership error = %v", err)
		}
	})
	t.Run("invalid dotted name", func(t *testing.T) {
		err := NewCatalog().Register("golem15.hello", fstest.MapFS{}, []string{"golem15.hello::mail.hello/../x"}, nil)
		if err == nil || !strings.Contains(err.Error(), "invalid mail name") {
			t.Fatalf("invalid name error = %v", err)
		}
	})
	t.Run("missing template names plugin and dotted name", func(t *testing.T) {
		err := NewCatalog().Register("golem15.hello", fstest.MapFS{}, []string{"golem15.hello::mail.missing"}, nil)
		if err == nil || !strings.Contains(err.Error(), "golem15.hello::mail.missing") {
			t.Fatalf("missing template error = %v", err)
		}
	})
}