From b3273545b55621ace932c39265a969d61b3ad53a Mon Sep 17 00:00:00 2001
From: Adora Laura Kalb <adora@lila.network>
Date: Thu, 25 Jul 2024 21:45:29 +0200
Subject: [PATCH] add alias decision logic

---
 cmd/mailcow-admin-aliases/main.go | 28 ++++++++++++++--------------
 internal/mailcow/aliases.go       | 21 +++++++++++++--------
 internal/misc/misc.go             | 10 ++++++++++
 3 files changed, 37 insertions(+), 22 deletions(-)

diff --git a/cmd/mailcow-admin-aliases/main.go b/cmd/mailcow-admin-aliases/main.go
index abd8662..61d2c2c 100644
--- a/cmd/mailcow-admin-aliases/main.go
+++ b/cmd/mailcow-admin-aliases/main.go
@@ -13,6 +13,7 @@ import (
 	"code.lila.network/adoralaura/mailcow-admin-aliases/internal/configuration"
 	"code.lila.network/adoralaura/mailcow-admin-aliases/internal/logging"
 	"code.lila.network/adoralaura/mailcow-admin-aliases/internal/mailcow"
+	"code.lila.network/adoralaura/mailcow-admin-aliases/internal/misc"
 	"github.com/spf13/pflag"
 )
 
@@ -39,26 +40,25 @@ func main() {
 		os.Exit(1)
 	}
 
-	for _, domain := range domains {
-		for _, prefix := range cfg.MailPrefixes {
-			address := prefix + "@" + domain.DomainName
-			if address != cfg.AdminEmail {
-				wantedAliases = append(wantedAliases, address)
-			}
-		}
-	}
-
-	aliases, err := mailcow.LoadAliases(cfg)
+	existingAliases, existingAliasesSlice, err := mailcow.LoadAliases(cfg)
 	if err != nil {
 		slog.Error("failed to get aliases", "error", err.Error())
 		os.Exit(1)
 	}
-	slog.Info(fmt.Sprintf("Found %v domains, %v aliases.", len(domains), len(aliases)))
-
-	for _, alias := range aliases {
-		for _, wantedPrefix := range cfg.MailPrefixes {
+	slog.Info(fmt.Sprintf("Found %v domains, %v aliases.", len(domains), len(existingAliases)))
 
+	for _, domain := range domains {
+		for _, prefix := range cfg.MailPrefixes {
+			address := prefix + "@" + domain.DomainName
+			if address != cfg.AdminEmail && !misc.StringIsInStringSlice(existingAliasesSlice, address) {
+				slog.Info(fmt.Sprintf("%v: Adding to wanted alias list", address))
+				wantedAliases = append(wantedAliases, address)
+			} else {
+				slog.Info(fmt.Sprintf("%v: Ignoring alias", address))
+			}
 		}
 	}
 
+	// TODO: create aliases
+
 }
diff --git a/internal/mailcow/aliases.go b/internal/mailcow/aliases.go
index 1be7cc3..8608de7 100644
--- a/internal/mailcow/aliases.go
+++ b/internal/mailcow/aliases.go
@@ -36,8 +36,9 @@ func NewAlias(alias string, destination string) MailcowAlias {
 	return a
 }
 
-func LoadAliases(cfg configuration.Config) ([]MailcowAlias, error) {
-	var domains []MailcowAlias
+func LoadAliases(cfg configuration.Config) ([]MailcowAlias, []string, error) {
+	var aliases []MailcowAlias
+	var aliasSlice []string
 
 	url := cfg.ApiEndpoint + configuration.AllAliasesApiEndpoint
 	method := "GET"
@@ -48,14 +49,14 @@ func LoadAliases(cfg configuration.Config) ([]MailcowAlias, error) {
 	slog.Debug("alias request", "method", method, "url", url)
 
 	if err != nil {
-		return []MailcowAlias{}, fmt.Errorf("failed to create alias http request: %w", err)
+		return []MailcowAlias{}, []string{}, fmt.Errorf("failed to create alias http request: %w", err)
 	}
 	req.Header.Add("accept", "application/json")
 	req.Header.Add("X-API-Key", cfg.ApiKey)
 
 	res, err := client.Do(req)
 	if err != nil {
-		return []MailcowAlias{}, fmt.Errorf("failed to request aliases from server: %w", err)
+		return []MailcowAlias{}, []string{}, fmt.Errorf("failed to request aliases from server: %w", err)
 	}
 	defer res.Body.Close()
 
@@ -63,13 +64,17 @@ func LoadAliases(cfg configuration.Config) ([]MailcowAlias, error) {
 
 	body, err := io.ReadAll(res.Body)
 	if err != nil {
-		return []MailcowAlias{}, fmt.Errorf("failed to read alias request body: %w", err)
+		return []MailcowAlias{}, []string{}, fmt.Errorf("failed to read alias request body: %w", err)
 	}
 
-	err = json.Unmarshal(body, &domains)
+	err = json.Unmarshal(body, &aliases)
 	if err != nil {
-		return []MailcowAlias{}, fmt.Errorf("failed to unmarshal alias request body: %w", err)
+		return []MailcowAlias{}, []string{}, fmt.Errorf("failed to unmarshal alias request body: %w", err)
 	}
 
-	return domains, nil
+	for _, alias := range aliases {
+		aliasSlice = append(aliasSlice, alias.Address)
+	}
+
+	return aliases, aliasSlice, nil
 }
diff --git a/internal/misc/misc.go b/internal/misc/misc.go
index 55d1195..ffba75c 100644
--- a/internal/misc/misc.go
+++ b/internal/misc/misc.go
@@ -9,3 +9,13 @@ func StringIsInStringSlice(slice []string, s string) bool {
 
 	return false
 }
+
+func RemoveStringFromStringSlice(slice []string, s string) []string {
+	a := []string{}
+	for _, item := range slice {
+		if item != s {
+			a = append(a, item)
+		}
+	}
+	return a
+}