general cleanup - removed old comments, enforced naming conventions etc

2026-03-04 23:29:58 -05:00
parent 44dad43f1d
commit 2c86bba235
55 changed files with 68 additions and 101 deletions
--- a/backend/internal/services/email_digest.go
+++ b/backend/internal/services/email_digest.go
@@ -0,0 +1,196 @@
+package services
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+
+	"github.com/kjannette/koin-ping/backend/internal/models"
+)
+
+const (
+	resendAPIURL          = "https://api.resend.com/emails"
+	emailHTTPTimeout      = 10 * time.Second
+	defaultDigestMaxItems = 50
+)
+
+var digestHTTPClient = &http.Client{Timeout: emailHTTPTimeout} //nolint:gochecknoglobals
+
+// handles email setup and digest sending via Resend.
+type EmailDigestService struct {
+	apiKey      string
+	fromAddress string
+	alertEvents *models.AlertEventModel
+	notifCfgs   *models.NotificationConfigModel
+}
+
+func NewEmailDigestService(
+	apiKey, fromAddress string,
+	alertEvents *models.AlertEventModel,
+	notifCfgs *models.NotificationConfigModel,
+) *EmailDigestService {
+	return &EmailDigestService{
+		apiKey:      apiKey,
+		fromAddress: fromAddress,
+		alertEvents: alertEvents,
+		notifCfgs:   notifCfgs,
+	}
+}
+
+// Configured returns true when the Resend API key is present.
+func (s *EmailDigestService) Configured() bool {
+	return s.apiKey != ""
+}
+
+// SetupEmail validates the email works by sending a welcome/confirmation
+// message via Resend. Called when a user saves their email in notification settings.
+func (s *EmailDigestService) SetupEmail(toAddress string) error {
+	if !s.Configured() {
+		return fmt.Errorf("email service not configured: RESEND_API_KEY not set") //nolint:err113
+	}
+
+	html := `
+<div style="font-family: sans-serif; max-width: 600px; margin: 0 auto;">
+  <h2 style="color: #333;">Welcome to Koin Ping Email Alerts</h2>
+  <p>Your email has been successfully configured for alert notifications.</p>
+  <p>You will receive alert digests at this address when events are triggered
+     on your watched addresses.</p>
+  <hr style="border: none; border-top: 1px solid #eee; margin: 24px 0;" />
+  <p style="font-size: 12px; color: #999;">Sent by Koin Ping</p>
+</div>`
+
+	return s.send(toAddress, "Koin Ping — Email Alerts Configured", html)
+}
+
+func (s *EmailDigestService) SendDigest(ctx context.Context, userID, toAddress string) error {
+	if !s.Configured() {
+		return fmt.Errorf("email service not configured: RESEND_API_KEY not set") //nolint:err113
+	}
+
+	events, err := s.alertEvents.ListRecentByUser(ctx, userID, defaultDigestMaxItems)
+	if err != nil {
+		return fmt.Errorf("fetch alert events: %w", err)
+	}
+
+	if len(events) == 0 {
+		log.Printf("No recent alerts for user %s — skipping digest", userID)
+		return nil
+	}
+
+	var rows string
+	for _, e := range events {
+		label := "—"
+		if e.AddressLabel != nil {
+			label = *e.AddressLabel
+		}
+		txLink := "—"
+		if e.TxHash != nil {
+			txLink = fmt.Sprintf(
+				`<a href="https://etherscan.io/tx/%s" style="color:#0066cc;">%s…</a>`,
+				*e.TxHash, (*e.TxHash)[:10],
+			)
+		}
+		rows += fmt.Sprintf(`
+      <tr>
+        <td style="padding:6px 8px; border-bottom:1px solid #eee;">%s</td>
+        <td style="padding:6px 8px; border-bottom:1px solid #eee;">%s</td>
+        <td style="padding:6px 8px; border-bottom:1px solid #eee;">%s</td>
+        <td style="padding:6px 8px; border-bottom:1px solid #eee; font-size:12px; color:#666;">%s</td>
+      </tr>`,
+			label, e.Message, txLink,
+			e.Timestamp.Format("Jan 2 15:04 UTC"),
+		)
+	}
+
+	html := fmt.Sprintf(`
+<div style="font-family: sans-serif; max-width: 700px; margin: 0 auto;">
+  <h2 style="color: #333;">Koin Ping — Alert Digest</h2>
+  <p>Here are your recent alerts (%d total):</p>
+  <table style="width:100%%; border-collapse:collapse; font-size:14px;">
+    <thead>
+      <tr style="background:#f5f5f5;">
+        <th style="padding:8px; text-align:left;">Address</th>
+        <th style="padding:8px; text-align:left;">Alert</th>
+        <th style="padding:8px; text-align:left;">Tx</th>
+        <th style="padding:8px; text-align:left;">Time</th>
+      </tr>
+    </thead>
+    <tbody>%s</tbody>
+  </table>
+  <hr style="border:none; border-top:1px solid #eee; margin:24px 0;" />
+  <p style="font-size:12px; color:#999;">Sent by Koin Ping</p>
+</div>`, len(events), rows)
+
+	subject := fmt.Sprintf("Koin Ping Digest — %d alerts", len(events))
+
+	return s.send(toAddress, subject, html)
+}
+
+func (s *EmailDigestService) SendDigestsForAllUsers(ctx context.Context) (int, error) {
+	if !s.Configured() {
+		return 0, nil
+	}
+
+	configs, err := s.notifCfgs.ListEnabled(ctx)
+	if err != nil {
+		return 0, fmt.Errorf("list enabled configs: %w", err)
+	}
+
+	sent := 0
+	for _, cfg := range configs {
+		if cfg.Email == nil || *cfg.Email == "" {
+			continue
+		}
+		if err := s.SendDigest(ctx, cfg.UserID, *cfg.Email); err != nil {
+			log.Printf("Failed to send digest to user %s: %v", cfg.UserID, err)
+			continue
+		}
+		sent++
+	}
+
+	return sent, nil
+}
+
+type resendEmailPayload struct {
+	From    string `json:"from"`
+	To      string `json:"to"`
+	Subject string `json:"subject"`
+	HTML    string `json:"html"`
+}
+
+func (s *EmailDigestService) send(to, subject, html string) error {
+	payload := resendEmailPayload{
+		From:    s.fromAddress,
+		To:      to,
+		Subject: subject,
+		HTML:    html,
+	}
+
+	body, err := json.Marshal(payload)
+	if err != nil {
+		return fmt.Errorf("marshal email payload: %w", err)
+	}
+
+	req, err := http.NewRequest(http.MethodPost, resendAPIURL, bytes.NewReader(body))
+	if err != nil {
+		return fmt.Errorf("create request: %w", err)
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Authorization", "Bearer "+s.apiKey)
+
+	resp, err := digestHTTPClient.Do(req)
+	if err != nil {
+		return fmt.Errorf("send email via Resend: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode < 200 || resp.StatusCode >= 300 {
+		return fmt.Errorf("Resend API returned HTTP %d", resp.StatusCode) //nolint:err113
+	}
+
+	return nil
+}