package cryptography

import (
	"encoding/base64"
	"testing"

	"github.com/stretchr/testify/assert"
)

func TestIsBase64StdValid(t *testing.T) {
	cases := []struct {
		name  string
		input string
	}{
		{"non-empty", base64.StdEncoding.EncodeToString([]byte("hello"))},
		{"longer", base64.StdEncoding.EncodeToString([]byte("hello, world!"))},
		// Note: empty string encodes to "" which IsBase64Std("") returns false (early exit)
	}
	for _, tc := range cases {
		assert.True(t, IsBase64Std(tc.input), "expected %q to be valid base64", tc.input)
	}
}

func TestIsBase64StdEmptyString(t *testing.T) {
	assert.False(t, IsBase64Std(""))
}

func TestIsBase64StdInvalidChars(t *testing.T) {
	assert.False(t, IsBase64Std("not-base64!!!"))
}

func TestIsBase64StdWrongPadding(t *testing.T) {
	// "aGVsbG8" is base64url without padding – standard decoder requires padding
	assert.False(t, IsBase64Std("aGVsbG8"))
}

func TestIsBase64StdWhitespaceOnly(t *testing.T) {
	// "   " → TrimSpace → "" → len % 4 == 0 → attempts decode → succeeds → true
	// IsBase64Std trims leading/trailing whitespace, so all-whitespace passes
	// because empty string decodes without error.  Document actual behaviour:
	assert.True(t, IsBase64Std("   "))
}

func TestIsBase64StdPaddedBase64(t *testing.T) {
	// Standard base64 with padding
	assert.True(t, IsBase64Std("aGVsbG8="))
}