diff --git a/src/main_test.go b/src/main_test.go
new file mode 100644
index 0000000..f613369
--- /dev/null
+++ b/src/main_test.go
@@ -0,0 +1,125 @@
+package main
+
+import (
+	"encoding/json"
+	"os"
+	"reflect"
+	"testing"
+)
+
+func TestSanitizeFilename(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected string
+	}{
+		{"file:name.mp4", "file_name.mp4"},
+		{"file/name.mp4", "file_name.mp4"},
+		{"file\\name.mp4", "file_name.mp4"},
+		{"file?name.mp4", "file_name.mp4"},
+		{"file*name.mp4", "file_name.mp4"},
+		{"file<name>.mp4", "file_name_.mp4"},
+		{".hidden", "hidden"},
+	}
+
+	for _, test := range tests {
+		result := sanitizeFilename(test.input)
+		if result != test.expected {
+			t.Errorf("sanitizeFilename(%q) = %q, want %q", test.input, result, test.expected)
+		}
+	}
+}
+
+func TestIsValidURL(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected bool
+	}{
+		{"https://example.com", true},
+		{"http://example.com", true},
+		{"ftp://example.com", true},
+		{"not a url", false},
+	}
+
+	for _, test := range tests {
+		result := isValidURL(test.input)
+		if result != test.expected {
+			t.Errorf("isValidURL(%q) = %v, want %v", test.input, result, test.expected)
+		}
+	}
+}
+
+func TestParseMetadata(t *testing.T) {
+	tests := []struct {
+		input    string
+		expected Metadata
+	}{
+		{"Show Title; serie; 01", Metadata{Title: "Show Title", Type: "serie", Season: "S01"}},
+		{"Movie Title; movie; ", Metadata{Title: "Movie Title", Type: "movie", Season: "S"}},
+		{"Invalid Metadata", Metadata{}},
+	}
+
+	for _, test := range tests {
+		result := parseMetadata(test.input)
+		if !reflect.DeepEqual(result, test.expected) {
+			t.Errorf("parseMetadata(%q) = %v, want %v", test.input, result, test.expected)
+		}
+	}
+}
+
+func TestParseInputFile(t *testing.T) {
+	tempFile, err := os.CreateTemp("", "test_input_*.json")
+	if err != nil {
+		t.Fatalf("Failed to create temp file: %v", err)
+	}
+	defer os.Remove(tempFile.Name())
+
+	testData := Items{
+		Items: []Item{
+			{MPD: "http://example.com/video1.mpd", Filename: "video1.mp4"},
+			{MPD: "http://example.com/video2.mpd", Filename: "video2.mp4"},
+		},
+	}
+	jsonData, _ := json.Marshal(testData)
+	if _, err := tempFile.Write(jsonData); err != nil {
+		t.Fatalf("Failed to write to temp file: %v", err)
+	}
+	tempFile.Close()
+
+	items, err := parseInputFile(tempFile.Name())
+	if err != nil {
+		t.Fatalf("parseInputFile() returned an error: %v", err)
+	}
+
+	if len(items) != len(testData.Items) {
+		t.Errorf("parseInputFile() returned %d items, want %d", len(items), len(testData.Items))
+	}
+
+	for i, item := range items {
+		if !reflect.DeepEqual(item, testData.Items[i]) {
+			t.Errorf("parseInputFile() item %d = %v, want %v", i, item, testData.Items[i])
+		}
+	}
+}
+
+func TestGroupItemsBySeason(t *testing.T) {
+	items := []Item{
+		{Filename: "show1_s01e01.mp4", Metadata: "Show 1; serie; 01"},
+		{Filename: "show1_s01e02.mp4", Metadata: "Show 1; serie; 01"},
+		{Filename: "show2_s01e01.mp4", Metadata: "Show 2; serie; 01"},
+		{Filename: "movie1.mp4", Metadata: "Movie 1; movie; "},
+	}
+
+	grouped := groupItemsBySeason(items)
+
+	expectedGroups := map[string]int{
+		"Show 1 - S01": 2,
+		"Show 2 - S01": 1,
+		"Movies":       1,
+	}
+
+	for group, count := range expectedGroups {
+		if len(grouped[group]) != count {
+			t.Errorf("groupItemsBySeason() group %q has %d items, want %d", group, len(grouped[group]), count)
+		}
+	}
+}