2 files changed, 198 insertions, 0 deletions
diff --git a/backend/internal/alerts/alerts.go b/backend/internal/alerts/alerts.go
new file mode 100644
index 0000000..44d4a50
--- /dev/null
+++ b/backend/internal/alerts/alerts.go
@@ -0,0 +1,113 @@
+package alerts
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"time"
+
+	"yaum/internal/model"
+)
+
+type SMTPConfig struct {
+	Host     string
+	Port     int
+	Username string
+	Password string
+	From     string
+}
+
+func SendDiscord(webhookURL string, svc model.Service, hb model.Heartbeat, wasUp bool) {
+	color := 15548997
+	title := "🔴 Site Fora do Ar"
+	if hb.IsUp {
+		color = 5763719
+		title = "🟢 Site Recuperado"
+	}
+
+	desc := "o servico caiu"
+	fields := []map[string]any{
+		{"name": "URL", "value": svc.URL, "inline": true},
+		{"name": "Codigo", "value": fmt.Sprintf("`%d`", hb.StatusCode), "inline": true},
+		{"name": "Tempo", "value": fmt.Sprintf("%dms", hb.ResponseTimeMs), "inline": true},
+	}
+	if hb.ErrorMessage != "" {
+		fields = append(fields, map[string]any{"name": "Erro", "value": hb.ErrorMessage, "inline": false})
+	}
+	if hb.IsUp {
+		desc = "o servico voltou"
+	}
+
+	payload := map[string]any{
+		"embeds": []map[string]any{
+			{
+				"title":       title + " | " + svc.Name,
+				"description": desc,
+				"color":       color,
+				"fields":      fields,
+				"footer":      map[string]any{"text": "YAUM — Yet Another Uptime Monitor"},
+				"timestamp":   hb.TestedAt.Format(time.RFC3339),
+			},
+		},
+		"username": "YAUM",
+	}
+
+	data, _ := json.Marshal(payload)
+
+	client := &http.Client{Timeout: 10 * time.Second}
+	resp, err := client.Post(webhookURL, "application/json", bytes.NewReader(data))
+	if err != nil {
+		log.Printf("[alerta:discord] erro ao enviar: %v", err)
+		return
+	}
+	resp.Body.Close()
+	if resp.StatusCode >= 400 {
+		log.Printf("[alerta:discord] webhook retornou %d", resp.StatusCode)
+		return
+	}
+	log.Printf("[alerta:discord] webhook enviado para '%s'", svc.Name)
+}
+
+func SendEmail(svc model.Service, hb model.Heartbeat, wasUp bool, cfg *SMTPConfig) {
+	if cfg == nil || cfg.From == "" || cfg.Host == "" {
+		log.Println("[alerta:email] smtp nao configurado — pulando")
+		return
+	}
+
+	statusEmoji := "🟢"
+	statusTxt := "UP"
+	subject := "[YAUM] Site Recuperado: " + svc.Name
+	if !hb.IsUp {
+		statusEmoji = "🔴"
+		statusTxt = "DOWN"
+		subject = "[YAUM] Site Fora do Ar: " + svc.Name
+	}
+
+	body := fmt.Sprintf(`YAUM — Yet Another Uptime Monitor
+
+%s Status: %s
+
+Servico: %s
+URL: %s
+Status HTTP: %d
+Tempo de Resposta: %dms
+Mensagem: %s
+Testado em: %s
+`,
+		statusEmoji, statusTxt,
+		svc.Name, svc.URL, hb.StatusCode, hb.ResponseTimeMs, hb.ErrorMessage,
+		hb.TestedAt.Format("2006-01-02 15:04:05 MST"),
+	)
+
+	if err := sendMail(hostPort(cfg.Host, cfg.Port), cfg.Username, cfg.Password, cfg.From, []string{svc.AlertEmail}, subject, body); err != nil {
+		log.Printf("[alerta:email] erro: %v", err)
+		return
+	}
+	log.Printf("[alerta:email] email enviado para %s", svc.AlertEmail)
+}
+
+func hostPort(host string, port int) string {
+	return fmt.Sprintf("%s:%d", host, port)
+}
diff --git a/backend/internal/alerts/smtp.go b/backend/internal/alerts/smtp.go
new file mode 100644
index 0000000..5bb1ba8
--- /dev/null
+++ b/backend/internal/alerts/smtp.go
@@ -0,0 +1,85 @@
+package alerts
+
+import (
+	"crypto/tls"
+	"fmt"
+	"net/smtp"
+	"strings"
+)
+
+func sendMail(addr, user, pass, from string, to []string, subject, body string) error {
+	host := addr
+	for i, c := range addr {
+		if c == ':' {
+			host = addr[:i]
+			break
+		}
+	}
+
+	msg := fmt.Sprintf("From: %s\r\nTo: %s\r\nSubject: %s\r\nMIME-Version: 1.0\r\nContent-Type: text/plain; charset=UTF-8\r\n\r\n%s",
+		from, strings.Join(to, ", "), subject, body)
+
+	auth := newLoginAuth(user, pass)
+
+	c, err := smtp.Dial(addr)
+	if err != nil {
+		return fmt.Errorf("dial: %w", err)
+	}
+	defer c.Close()
+
+	if err := c.StartTLS(&tls.Config{ServerName: host}); err != nil {
+		return fmt.Errorf("starttls: %w", err)
+	}
+
+	if user != "" {
+		if err := c.Auth(auth); err != nil {
+			return fmt.Errorf("auth: %w", err)
+		}
+	}
+
+	if err := c.Mail(from); err != nil {
+		return fmt.Errorf("mail from: %w", err)
+	}
+	for _, addr := range to {
+		if err := c.Rcpt(addr); err != nil {
+			return fmt.Errorf("rcpt %s: %w", addr, err)
+		}
+	}
+
+	w, err := c.Data()
+	if err != nil {
+		return fmt.Errorf("data: %w", err)
+	}
+	if _, err := fmt.Fprint(w, msg); err != nil {
+		return fmt.Errorf("write: %w", err)
+	}
+	if err := w.Close(); err != nil {
+		return fmt.Errorf("close: %w", err)
+	}
+	return c.Quit()
+}
+
+type loginAuth struct {
+	user, pass string
+}
+
+func newLoginAuth(user, pass string) smtp.Auth {
+	return &loginAuth{user, pass}
+}
+
+func (a *loginAuth) Start(server *smtp.ServerInfo) (string, []byte, error) {
+	return "LOGIN", []byte(a.user), nil
+}
+
+func (a *loginAuth) Next(fromServer []byte, more bool) ([]byte, error) {
+	if more {
+		msg := string(fromServer)
+		switch {
+		case strings.EqualFold(msg, "Username:"):
+			return []byte(a.user), nil
+		case strings.EqualFold(msg, "Password:"):
+			return []byte(a.pass), nil
+		}
+	}
+	return nil, nil
+}