package mail

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"
)

// cases renders every message with realistic data. Each entry's key is the
// template name, optionally with a "/variant" suffix for a message whose
// branches are worth seeing separately.
func cases() map[string]any {
	s := Sender{PublicURL: "https://vantage-hq.hostxtra.co.uk"}
	now := time.Now().UTC()
	day := 24 * time.Hour
	return map[string]any{
		"verification": s.verificationData("sam@example.com", "3f9c2a7d1e"),
		"invite":       s.inviteData("sam@example.com", "Northwind Ops", "8a1b2c3d4e"),
		"license": licenseData("northwind-prod",
			"eyJ2IjoxLCJpbnN0YW5jZSI6Im5vcnRod2luZC1wcm9kIiwidGllciI6ImZyZWUiLCJleHAiOjE3OTk5OTk5OTl9.MEUCIQDk3v1rX0sX7kQ2m9WQ1o0q8pWm6lq3vRjz8yN0yX4bGQIgYk2Fh7s"),
		"instanceready":          instanceReadyData("northwind-prod", "https://northwind-prod.vantage.hostxtra.co.uk", now.Add(30*day)),
		"instanceready/nologin":  instanceReadyData("northwind-prod", "", now.Add(30*day)),
		"renewed":                renewedData("northwind-prod", now.Add(30*day)),
		"expiring":               expiringData("northwind-prod", s.PublicURL, now.Add(7*day)),
		"expired":                expiredData("northwind-prod", s.PublicURL, now.Add(14*day)),
		"expired/noreaper":       expiredData("northwind-prod", s.PublicURL, time.Time{}),
		"deletionwarning":        deletionWarningData("northwind-prod", s.PublicURL, now.Add(7*day), 7),
		"deletionwarning/1day":   deletionWarningData("northwind-prod", s.PublicURL, now.Add(day), 1),
		"cancelled":              s.billingData("northwind-prod"),
		"pastdue":                s.billingData("northwind-prod"),
		"monitoralert":           MonitorEvent{MonitorName: "api.northwind.io", Type: "http", OldStatus: "up", NewStatus: "down", Message: "GET /healthz returned 503 Service Unavailable after 2.4s", Time: now, Down: true},
		"monitoralert/recovered": MonitorEvent{MonitorName: "api.northwind.io", Type: "http", OldStatus: "down", NewStatus: "up", Message: "200 OK in 182ms", Time: now},
		"contact": struct {
			Enquiry
			Received string
		}{Enquiry{Name: "Priya Shah", Email: "priya@acme.io", Servers: "50-100", Topic: "Sales",
			Message: "Hi,\n\nWe run about 80 Linux boxes across two sites and are looking at Vantage for patching and uptime.\nCould we get a demo next week?"}, now.Format(time.RFC1123)},
		"vuln_digest": VulnDigest{InstanceName: "northwind-prod", Count: 14, TopSeverity: "critical",
			Summary: "14 new findings across 3 servers, 2 of them critical.",
			Rows: []VulnDigestRow{
				{CVEID: "CVE-2026-31337", Severity: "critical", PackageName: "openssl", ServerName: "web-01", FixedIn: "3.0.15-1"},
				{CVEID: "CVE-2026-29001", Severity: "critical", PackageName: "sudo", ServerName: "db-02", FixedIn: "1.9.16p2"},
				{CVEID: "GHSA-4xq2-9r7m-p3wv", Severity: "high", PackageName: "golang.org/x/net", ServerName: "web-01"},
				{CVEID: "CVE-2026-20488", Severity: "medium", PackageName: "curl", ServerName: "worker-03", FixedIn: "8.9.1"},
				{CVEID: "CVE-2025-48112", Severity: "low", PackageName: "less", ServerName: "worker-03"},
			},
			More: 9, DBAge: "2 days"},
		"announcement": announcementData{
			Announcement: sampleAnnouncement(),
			BodyHTML:     "<p>Workflows can now run <strong>on a schedule</strong>.</p>",
		},
		"accountlocked":     sampleNotice(),
		"disputereminder":   sampleNotice(),
		"accountterminated": sampleNotice(),
		"accountrestored":   sampleNotice(),
	}
}

// TestRenderAll renders every template and fails if one exists that no case
// covers. The templates are parsed in init(), so without this test a mistyped
// field is a boot-time panic in three services.
//
// Set MAIL_PREVIEW_DIR to also write each rendering to disk for a look.
func TestRenderAll(t *testing.T) {
	covered := map[string]bool{}
	dir := os.Getenv("MAIL_PREVIEW_DIR")

	for key, data := range cases() {
		name, _, _ := strings.Cut(key, "/")
		covered[name] = true

		m, err := render(name, data, "https://vantage-hq.hostxtra.co.uk")
		if err != nil {
			t.Fatalf("%s: %v", key, err)
		}
		if m.Subject == "" {
			t.Errorf("%s: empty subject", key)
		}
		for part, body := range map[string]string{"subject": m.Subject, "text": m.Text, "html": m.HTML} {
			if strings.Contains(body, "<no value>") {
				t.Errorf("%s: %s part has <no value>", key, part)
			}
			if strings.Contains(body, "—") {
				t.Errorf("%s: %s part has an em dash", key, part)
			}
		}

		if dir != "" {
			base := filepath.Join(dir, strings.ReplaceAll(key, "/", "--"))
			_ = os.WriteFile(base+".html", []byte(m.HTML), 0o644)
			_ = os.WriteFile(base+".txt", []byte(m.Text), 0o644)
			_ = os.WriteFile(base+".subject", []byte(m.Subject), 0o644)
		}
	}

	for name := range sets {
		if !covered[name] {
			t.Errorf("template %q has no render case", name)
		}
	}
}

// TestRenderNoPortal checks the footer degrades when the sender has no
// PublicURL, as a monitor notification channel does not.
func TestRenderNoPortal(t *testing.T) {
	m, err := render("monitoralert", MonitorEvent{MonitorName: "m", Type: "tcp", Time: time.Now(), Down: true}, "")
	if err != nil {
		t.Fatal(err)
	}
	if strings.Contains(m.HTML, "/billing") {
		t.Error("footer links rendered without a portal URL")
	}
}