From 91048c16f86b66a5418ef651cdf8a4c6b2b50aec Mon Sep 17 00:00:00 2001
From: Stavros <steveiliop56@gmail.com>
Date: Thu, 11 Sep 2025 23:10:36 +0300
Subject: [PATCH] feat: add flag decoder (candidate)

---
 internal/config/config.go                     | 10 ++++
 internal/utils/decoders/flags_decoder.go      | 55 +++++++++++++++++
 internal/utils/decoders/flags_decoder_test.go | 60 +++++++++++++++++++
 internal/utils/decoders/label_decoder_test.go | 13 ++--
 4 files changed, 129 insertions(+), 9 deletions(-)
 create mode 100644 internal/utils/decoders/flags_decoder.go
 create mode 100644 internal/utils/decoders/flags_decoder_test.go

diff --git a/internal/config/config.go b/internal/config/config.go
index 7ccedd3..6b143bf 100644
--- a/internal/config/config.go
+++ b/internal/config/config.go
@@ -174,3 +174,13 @@ type AppPath struct {
 	Allow string
 	Block string
 }
+
+// Flags
+
+type Providers struct {
+	Providers map[string]ProviderConfig
+}
+
+type ProviderConfig struct {
+	Config OAuthServiceConfig
+}
diff --git a/internal/utils/decoders/flags_decoder.go b/internal/utils/decoders/flags_decoder.go
new file mode 100644
index 0000000..4154157
--- /dev/null
+++ b/internal/utils/decoders/flags_decoder.go
@@ -0,0 +1,55 @@
+package decoders
+
+import (
+	"strings"
+	"tinyauth/internal/config"
+	"tinyauth/internal/utils"
+
+	"github.com/traefik/paerser/parser"
+)
+
+func DecodeFlags(flags map[string]string) (config.Providers, error) {
+	// Normalize flags (sorry to whoever has to read this)
+	// --providers-client1-client-id -> tinyauth.providers.client1.clientId
+	normalized := make(map[string]string)
+	for k, v := range flags {
+		newKey := ""
+
+		nk := strings.TrimPrefix(k, "--")
+		parts := strings.SplitN(nk, "-", 4)
+
+		for i, part := range parts {
+			if i == 3 {
+				subParts := strings.Split(part, "-")
+				for j, subPart := range subParts {
+					if j == 0 {
+						newKey += "." + subPart
+					} else {
+						newKey += utils.Capitalize(subPart)
+					}
+				}
+				continue
+			}
+			if i == 0 {
+				newKey += part
+				continue
+			}
+			newKey += "." + part
+		}
+
+		newKey = "tinyauth." + newKey
+		normalized[newKey] = v
+
+	}
+
+	// Decode
+	var providers config.Providers
+
+	err := parser.Decode(normalized, &providers, "tinyauth", "tinyauth.providers")
+
+	if err != nil {
+		return config.Providers{}, err
+	}
+
+	return providers, nil
+}
diff --git a/internal/utils/decoders/flags_decoder_test.go b/internal/utils/decoders/flags_decoder_test.go
new file mode 100644
index 0000000..a10760a
--- /dev/null
+++ b/internal/utils/decoders/flags_decoder_test.go
@@ -0,0 +1,60 @@
+package decoders_test
+
+import (
+	"testing"
+	"tinyauth/internal/config"
+	"tinyauth/internal/utils/decoders"
+
+	"gotest.tools/v3/assert"
+)
+
+func TestDecodeFlags(t *testing.T) {
+	// Variables
+	expected := config.Providers{
+		Providers: map[string]config.ProviderConfig{
+			"client1": {
+				Config: config.OAuthServiceConfig{
+					ClientID:           "client1-id",
+					ClientSecret:       "client1-secret",
+					Scopes:             []string{"client1-scope1", "client1-scope2"},
+					RedirectURL:        "client1-redirect-url",
+					AuthURL:            "client1-auth-url",
+					UserinfoURL:        "client1-user-info-url",
+					InsecureSkipVerify: false,
+				},
+			},
+			"client2": {
+				Config: config.OAuthServiceConfig{
+					ClientID:           "client2-id",
+					ClientSecret:       "client2-secret",
+					Scopes:             []string{"client2-scope1", "client2-scope2"},
+					RedirectURL:        "client2-redirect-url",
+					AuthURL:            "client2-auth-url",
+					UserinfoURL:        "client2-user-info-url",
+					InsecureSkipVerify: false,
+				},
+			},
+		},
+	}
+	test := map[string]string{
+		"--providers-client1-config-client-id":            "client1-id",
+		"--providers-client1-config-client-secret":        "client1-secret",
+		"--providers-client1-config-scopes":               "client1-scope1,client1-scope2",
+		"--providers-client1-config-redirect-url":         "client1-redirect-url",
+		"--providers-client1-config-auth-url":             "client1-auth-url",
+		"--providers-client1-config-user-info-url":        "client1-user-info-url",
+		"--providers-client1-config-insecure-skip-verify": "false",
+		"--providers-client2-config-client-id":            "client2-id",
+		"--providers-client2-config-client-secret":        "client2-secret",
+		"--providers-client2-config-scopes":               "client2-scope1,client2-scope2",
+		"--providers-client2-config-redirect-url":         "client2-redirect-url",
+		"--providers-client2-config-auth-url":             "client2-auth-url",
+		"--providers-client2-config-user-info-url":        "client2-user-info-url",
+		"--providers-client2-config-insecure-skip-verify": "false",
+	}
+
+	// Test
+	res, err := decoders.DecodeFlags(test)
+	assert.NilError(t, err)
+	assert.DeepEqual(t, expected, res)
+}
diff --git a/internal/utils/decoders/label_decoder_test.go b/internal/utils/decoders/label_decoder_test.go
index 1df885c..63189d1 100644
--- a/internal/utils/decoders/label_decoder_test.go
+++ b/internal/utils/decoders/label_decoder_test.go
@@ -1,10 +1,11 @@
 package decoders_test
 
 import (
-	"reflect"
 	"testing"
 	"tinyauth/internal/config"
 	"tinyauth/internal/utils/decoders"
+
+	"gotest.tools/v3/assert"
 )
 
 func TestDecodeLabels(t *testing.T) {
@@ -62,12 +63,6 @@ func TestDecodeLabels(t *testing.T) {
 
 	// Test
 	result, err := decoders.DecodeLabels(test)
-
-	if err != nil {
-		t.Fatalf("Unexpected error: %v", err)
-	}
-
-	if reflect.DeepEqual(expected, result) == false {
-		t.Fatalf("Expected %v but got %v", expected, result)
-	}
+	assert.NilError(t, err)
+	assert.DeepEqual(t, expected, result)
 }