feat: add stats page

internal/service/feedback_service.go

@@ -0,0 +1,167 @@
+// Package service — feedback flow. Sits between the feedback handler
+// and FeedbackRepo: validates the submission, writes the row, then
+// fans an HTML notification email out to every address listed in
+// FEEDBACK_ADMIN_EMAILS. The email is fire-and-forget — transient
+// send failures are logged and don't fail the request, because the
+// row is already in the DB and visible on /stats.
+package service
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"html/template"
+	"strings"
+
+	"github.com/prabhupadasays/spsays-bff/internal/model"
+	"github.com/prabhupadasays/spsays-bff/internal/repository"
+	"github.com/prabhupadasays/spsays-bff/pkg/mailer"
+	"go.uber.org/zap"
+)
+
+type FeedbackService struct {
+	repo   *repository.FeedbackRepo
+	mail   mailer.Mailer
+	admins []string
+	logger *zap.Logger
+}
+
+func NewFeedbackService(repo *repository.FeedbackRepo, mail mailer.Mailer, admins []string, logger *zap.Logger) *FeedbackService {
+	return &FeedbackService{repo: repo, mail: mail, admins: admins, logger: logger}
+}
+
+// Allowed categories — kept lowercase in storage so dashboards group
+// cleanly. The frontend dropdown sends one of these exact strings.
+var feedbackCategories = map[string]bool{
+	"bug":     true,
+	"feature": true,
+	"general": true,
+	"other":   true,
+}
+
+// Submit persists a feedback row and fires the admin email.
+//
+// userID is nil for anonymous submissions; contactEmail is the
+// optional reply-to in that case. For authed users we ignore whatever
+// the form sent and read the canonical email off the joined user row
+// when assembling the notification — that keeps the reply path
+// trustworthy (the form can't lie about who's writing).
+func (s *FeedbackService) Submit(ctx context.Context, userID *string, category, message string, contactEmail *string) (*model.Feedback, error) {
+	category = strings.ToLower(strings.TrimSpace(category))
+	if !feedbackCategories[category] {
+		return nil, errors.New("invalid category")
+	}
+	message = strings.TrimSpace(message)
+	if message == "" {
+		return nil, errors.New("message is required")
+	}
+	if len(message) > 5000 {
+		return nil, errors.New("message too long (max 5000)")
+	}
+
+	if userID == nil {
+		if contactEmail == nil || strings.TrimSpace(*contactEmail) == "" {
+			return nil, errors.New("contact_email is required when not logged in")
+		}
+		trimmed := strings.TrimSpace(*contactEmail)
+		contactEmail = &trimmed
+	} else {
+		// Authed: ignore client-supplied contact_email; user row owns it.
+		contactEmail = nil
+	}
+
+	f, err := s.repo.Create(ctx, userID, category, message, contactEmail)
+	if err != nil {
+		return nil, err
+	}
+
+	// Hydrate the joined author fields for the email template. Failing
+	// the lookup isn't worth failing the request — we fall back to
+	// "anonymous" rather than 500ing on the user.
+	if userID != nil {
+		if full, err := s.repo.FindByID(ctx, f.ID); err == nil {
+			f = full
+		} else {
+			s.logger.Warn("feedback hydrate failed; sending email without author info",
+				zap.String("feedback_id", f.ID), zap.Error(err))
+		}
+	}
+
+	s.notifyAdmins(f)
+	return f, nil
+}
+
+// notifyAdmins fires one HTML email per configured admin. Each
+// failure logs and falls through — the row is persisted so a missed
+// email is annoying but not data-losing.
+func (s *FeedbackService) notifyAdmins(f *model.Feedback) {
+	if len(s.admins) == 0 {
+		s.logger.Info("feedback received but no admin recipients configured",
+			zap.String("feedback_id", f.ID))
+		return
+	}
+	body, err := renderFeedbackEmail(f)
+	if err != nil {
+		s.logger.Warn("render feedback email failed", zap.Error(err))
+		return
+	}
+	subject := fmt.Sprintf("[Feedback · %s] %s", f.Category, summarize(f.Message, 60))
+	for _, to := range s.admins {
+		if err := s.mail.Send(to, subject, body); err != nil {
+			s.logger.Warn("feedback email send failed",
+				zap.String("to", to), zap.Error(err))
+		}
+	}
+}
+
+func summarize(s string, max int) string {
+	s = strings.TrimSpace(strings.ReplaceAll(s, "\n", " "))
+	runes := []rune(s)
+	if len(runes) <= max {
+		return s
+	}
+	return string(runes[:max-1]) + "…"
+}
+
+var feedbackEmailTpl = template.Must(template.New("feedback").Parse(`<p><strong>New feedback received</strong></p>
+<p><strong>Category:</strong> {{.Category}}<br>
+<strong>Submitted:</strong> {{.CreatedAt}}<br>
+<strong>From:</strong> {{.From}}</p>
+<p><strong>Message:</strong></p>
+<pre style="white-space:pre-wrap;font-family:inherit;background:#fafafa;padding:0.75em 1em;border-radius:6px;border:1px solid #eee">{{.Message}}</pre>
+<p style="color:#999;font-size:12px">Feedback ID: {{.ID}}</p>`))
+
+func renderFeedbackEmail(f *model.Feedback) (string, error) {
+	var from string
+	switch {
+	case f.AuthorHandle != nil && *f.AuthorHandle != "":
+		from = fmt.Sprintf("%s (@%s)", derefOr(f.AuthorName, "—"), *f.AuthorHandle)
+		if f.AuthorEmail != nil && *f.AuthorEmail != "" {
+			from += " — " + *f.AuthorEmail
+		}
+	case f.ContactEmail != nil && *f.ContactEmail != "":
+		from = "anonymous — " + *f.ContactEmail
+	default:
+		from = "anonymous"
+	}
+	var buf bytes.Buffer
+	err := feedbackEmailTpl.Execute(&buf, map[string]any{
+		"Category":  f.Category,
+		"Message":   f.Message,
+		"From":      from,
+		"CreatedAt": f.CreatedAt.Format("2006-01-02 15:04:05 MST"),
+		"ID":        f.ID,
+	})
+	if err != nil {
+		return "", err
+	}
+	return buf.String(), nil
+}
+
+func derefOr(p *string, fallback string) string {
+	if p == nil || *p == "" {
+		return fallback
+	}
+	return *p
+}