// Version Support Integration Tests
//
// Comprehensive integration tests for version functionality:
//
// - TestVersionIntegrationWorkflow: End-to-end workflow testing
//   - Creating initial version with proper metadata
//   - Creating multiple versions with timestamp updates
//   - Retrieving specific versions by name
//   - Promoting old versions to current
//   - Testing version serial number limits (999/day)
//   - Error cases and edge conditions
//
// - TestVersionConcurrency: Tests concurrent read operations
//
// - TestVersionCompatibility: Tests handling of legacy non-versioned secrets
//
// Test Environment:
// - Uses in-memory filesystem (afero.MemMapFs)
// - Consistent test mnemonic for reproducible keys
// - Proper cleanup and isolation between tests

//nolint:testpackage // uses white-box test helpers shared with this package
package vault

import (
	"errors"
	"fmt"
	"path/filepath"
	"testing"
	"time"

	"filippo.io/age"
	"git.eeqj.de/sneak/secret/internal/secret"
	"git.eeqj.de/sneak/secret/pkg/agehd"
	"github.com/awnumar/memguard"
	"github.com/spf13/afero"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

// errUnexpectedValue is returned by concurrent readers when a secret value
// does not match the expected contents.
var errUnexpectedValue = errors.New("unexpected value")

// TestVersionIntegrationWorkflow tests the complete version workflow
//
//nolint:paralleltest // t.Setenv forbids parallel subtests
func TestVersionIntegrationWorkflow(t *testing.T) {
	fs := afero.NewMemMapFs()

	// Set mnemonic for testing
	t.Setenv(secret.EnvMnemonic, testMnemonic)

	// Create vault
	vault, err := CreateVault(fs, testStateDir, "test")
	require.NoError(t, err)

	// Derive and store long-term key from mnemonic
	ltIdentity, err := agehd.DeriveIdentity(testMnemonic, 0)
	require.NoError(t, err)

	// Store long-term public key in vault
	vaultDir, _ := vault.GetDirectory()
	ltPubKeyPath := filepath.Join(vaultDir, "pub.age")

	err = afero.WriteFile(fs, ltPubKeyPath,
		[]byte(ltIdentity.Recipient().String()), 0o600)
	require.NoError(t, err)

	// Unlock the vault
	vault.Unlock(ltIdentity)

	secretName := "integration/test"

	// Step 1: Create initial version
	t.Run("create_initial_version", func(t *testing.T) {
		testCreateInitialVersion(t, fs, vault, ltIdentity, vaultDir, secretName)
	})

	// Step 2: Create second version
	t.Run("create_second_version", func(t *testing.T) {
		testCreateSecondVersion(t, fs, vault, ltIdentity, vaultDir, secretName)
	})

	// Step 3: Create third version
	t.Run("create_third_version", func(t *testing.T) {
		testCreateThirdVersion(t, fs, vault, vaultDir, secretName)
	})

	// Step 4: Retrieve specific versions
	t.Run("retrieve_specific_versions", func(t *testing.T) {
		testRetrieveSpecificVersions(t, fs, vault, vaultDir, secretName)
	})

	// Step 5: Promote old version to current
	t.Run("promote_old_version", func(t *testing.T) {
		testPromoteOldVersion(t, fs, vault, ltIdentity, vaultDir, secretName)
	})

	// Step 6: Test version limits
	t.Run("version_serial_limits", func(t *testing.T) {
		testVersionSerialLimits(t, fs, vault, vaultDir)
	})

	// Step 7: Test error cases
	t.Run("error_cases", func(t *testing.T) {
		testVersionErrorCases(t, vault, secretName)
	})
}

func testCreateInitialVersion(
	t *testing.T, fs afero.Fs, vault *Vault,
	ltIdentity *age.X25519Identity, vaultDir, secretName string,
) {
	t.Helper()

	addTestSecretToVault(t, vault, secretName, []byte("version-1-data"), false)

	// Verify secret can be retrieved
	value, err := vault.GetSecret(secretName)
	require.NoError(t, err)
	assert.Equal(t, []byte("version-1-data"), value)

	// Verify version directory structure
	secretDir := filepath.Join(vaultDir, "secrets.d", "integration%test")
	versions, err := secret.ListVersions(fs, secretDir)
	require.NoError(t, err)
	assert.Len(t, versions, 1)

	// Verify current symlink exists
	currentVersion, err := secret.GetCurrentVersion(fs, secretDir)
	require.NoError(t, err)
	assert.Equal(t, versions[0], currentVersion)

	// Verify metadata
	version := secret.NewVersion(vault, secretName, versions[0])
	err = version.LoadMetadata(ltIdentity)
	require.NoError(t, err)
	assert.NotNil(t, version.Metadata.CreatedAt)
	assert.NotNil(t, version.Metadata.NotBefore)
	assert.Equal(t, int64(1), version.Metadata.NotBefore.Unix()) // epoch + 1
	// NotAfter should be nil for current version
	assert.Nil(t, version.Metadata.NotAfter)
}

func testCreateSecondVersion(
	t *testing.T, fs afero.Fs, vault *Vault,
	ltIdentity *age.X25519Identity, vaultDir, secretName string,
) {
	t.Helper()

	// Small delay to ensure different timestamps
	time.Sleep(10 * time.Millisecond)

	// Get first version name before creating second
	secretDir := filepath.Join(vaultDir, "secrets.d", "integration%test")

	versions, err := secret.ListVersions(fs, secretDir)
	require.NoError(t, err)

	firstVersionName := versions[0]

	// Create second version
	addTestSecretToVault(t, vault, secretName, []byte("version-2-data"), true)

	// Verify new value is current
	value, err := vault.GetSecret(secretName)
	require.NoError(t, err)
	assert.Equal(t, []byte("version-2-data"), value)

	// Verify we now have two versions
	versions, err = secret.ListVersions(fs, secretDir)
	require.NoError(t, err)
	assert.Len(t, versions, 2)

	// Verify first version metadata was updated with notAfter
	firstVersion := secret.NewVersion(vault, secretName, firstVersionName)
	err = firstVersion.LoadMetadata(ltIdentity)
	require.NoError(t, err)
	assert.NotNil(t, firstVersion.Metadata.NotAfter)

	// Verify second version metadata
	secondVersion := secret.NewVersion(vault, secretName, versions[0])
	err = secondVersion.LoadMetadata(ltIdentity)
	require.NoError(t, err)
	assert.NotNil(t, secondVersion.Metadata.NotBefore)
	assert.Nil(t, secondVersion.Metadata.NotAfter)

	// NotBefore of second should equal NotAfter of first
	assert.Equal(t, firstVersion.Metadata.NotAfter.Unix(),
		secondVersion.Metadata.NotBefore.Unix())
}

func testCreateThirdVersion(
	t *testing.T, fs afero.Fs, vault *Vault, vaultDir, secretName string,
) {
	t.Helper()

	time.Sleep(10 * time.Millisecond)

	addTestSecretToVault(t, vault, secretName, []byte("version-3-data"), true)

	// Verify we now have three versions
	secretDir := filepath.Join(vaultDir, "secrets.d", "integration%test")
	versions, err := secret.ListVersions(fs, secretDir)
	require.NoError(t, err)
	assert.Len(t, versions, 3)

	// Current should be version-3
	value, err := vault.GetSecret(secretName)
	require.NoError(t, err)
	assert.Equal(t, []byte("version-3-data"), value)
}

func testRetrieveSpecificVersions(
	t *testing.T, fs afero.Fs, vault *Vault, vaultDir, secretName string,
) {
	t.Helper()

	secretDir := filepath.Join(vaultDir, "secrets.d", "integration%test")
	versions, err := secret.ListVersions(fs, secretDir)
	require.NoError(t, err)
	require.Len(t, versions, 3)

	// Get each version by its name
	value1, err := vault.GetSecretVersion(secretName, versions[2]) // oldest
	require.NoError(t, err)
	assert.Equal(t, []byte("version-1-data"), value1)

	value2, err := vault.GetSecretVersion(secretName, versions[1]) // middle
	require.NoError(t, err)
	assert.Equal(t, []byte("version-2-data"), value2)

	value3, err := vault.GetSecretVersion(secretName, versions[0]) // newest
	require.NoError(t, err)
	assert.Equal(t, []byte("version-3-data"), value3)

	// Empty version should return current
	valueCurrent, err := vault.GetSecretVersion(secretName, "")
	require.NoError(t, err)
	assert.Equal(t, []byte("version-3-data"), valueCurrent)
}

func testPromoteOldVersion(
	t *testing.T, fs afero.Fs, vault *Vault,
	ltIdentity *age.X25519Identity, vaultDir, secretName string,
) {
	t.Helper()

	secretDir := filepath.Join(vaultDir, "secrets.d", "integration%test")
	versions, err := secret.ListVersions(fs, secretDir)
	require.NoError(t, err)

	// Promote the first version (oldest) to current
	oldestVersion := versions[2]
	err = secret.SetCurrentVersion(fs, secretDir, oldestVersion)
	require.NoError(t, err)

	// Verify current now returns the old version's value
	value, err := vault.GetSecret(secretName)
	require.NoError(t, err)
	assert.Equal(t, []byte("version-1-data"), value)

	// Verify the version metadata hasn't changed
	// (promoting shouldn't modify timestamps)
	version := secret.NewVersion(vault, secretName, oldestVersion)
	err = version.LoadMetadata(ltIdentity)
	require.NoError(t, err)
	// should still have its old notAfter
	assert.NotNil(t, version.Metadata.NotAfter)
}

func testVersionSerialLimits(
	t *testing.T, fs afero.Fs, vault *Vault, vaultDir string,
) {
	t.Helper()

	// Create a new secret for this test
	limitSecretName := "limit/test"
	secretDir := filepath.Join(vaultDir, "secrets.d", "limit%test", "versions")

	// Create 998 versions (we already have one from the first AddSecret)
	addTestSecretToVault(t, vault, limitSecretName, []byte("initial"), false)

	// Get today's date for consistent version names
	today := time.Now().Format("20060102")

	// Manually create many versions with same date
	for i := 2; i <= 998; i++ {
		versionName := fmt.Sprintf("%s.%03d", today, i)
		versionDir := filepath.Join(secretDir, versionName)
		err := fs.MkdirAll(versionDir, 0o755)
		require.NoError(t, err)
	}

	// Should be able to create one more (999)
	versionName, err := secret.GenerateVersionName(fs, filepath.Dir(secretDir))
	require.NoError(t, err)
	assert.Equal(t, today+".999", versionName)

	// Create the 999th version directory
	err = fs.MkdirAll(filepath.Join(secretDir, versionName), 0o755)
	require.NoError(t, err)

	// Should fail to create 1000th version
	_, err = secret.GenerateVersionName(fs, filepath.Dir(secretDir))
	require.Error(t, err)
	assert.Contains(t, err.Error(), "exceeded maximum versions per day")
}

func testVersionErrorCases(t *testing.T, vault *Vault, secretName string) {
	t.Helper()

	// Try to get non-existent version
	_, err := vault.GetSecretVersion(secretName, "99991231.999")
	require.Error(t, err)
	assert.Contains(t, err.Error(), "not found")

	// Try to get version of non-existent secret
	_, err = vault.GetSecretVersion("nonexistent/secret", "")
	require.Error(t, err)

	// Try to add secret without force when it exists
	failBuffer := memguard.NewBufferFromBytes([]byte("should-fail"))
	defer failBuffer.Destroy()

	err = vault.AddSecret(secretName, failBuffer, false)
	require.Error(t, err)
	assert.Contains(t, err.Error(), "already exists")
}

// TestVersionConcurrency tests concurrent version operations
//
//nolint:paralleltest // createTestVaultWithKey uses t.Setenv
func TestVersionConcurrency(t *testing.T) {
	fs := afero.NewMemMapFs()

	// Set up vault
	vault := createTestVaultWithKey(t, fs)

	secretName := "concurrent/test"

	// Create initial version
	addTestSecretToVault(t, vault, secretName, []byte("initial"), false)

	// Test concurrent reads
	t.Run("concurrent_reads", func(t *testing.T) {
		done := make(chan bool, 10)
		errCh := make(chan error, 10)

		for range 10 {
			go func() {
				value, err := vault.GetSecret(secretName)
				if err != nil {
					errCh <- err
				} else if string(value) != "initial" {
					errCh <- fmt.Errorf("%w: %s", errUnexpectedValue, value)
				}

				done <- true
			}()
		}

		// Wait for all goroutines
		for range 10 {
			<-done
		}

		// Check for errors
		select {
		case err := <-errCh:
			t.Fatalf("concurrent read failed: %v", err)
		default:
			// No errors
		}
	})
}

// TestVersionCompatibility tests that old secrets without versions still work
//
//nolint:paralleltest // createTestVaultWithKey uses t.Setenv
func TestVersionCompatibility(t *testing.T) {
	fs := afero.NewMemMapFs()

	// Set up vault
	vault := createTestVaultWithKey(t, fs)

	ltIdentity, err := vault.GetOrDeriveLongTermKey()
	require.NoError(t, err)

	// Manually create an old-style secret (no versions)
	secretName := "legacy/secret"
	vaultDir, _ := vault.GetDirectory()
	secretDir := filepath.Join(vaultDir, "secrets.d", "legacy%secret")
	err = fs.MkdirAll(secretDir, 0o755)
	require.NoError(t, err)

	// Create old-style encrypted value directly in secret directory
	testValue := []byte("legacy-value")

	testValueBuffer := memguard.NewBufferFromBytes(testValue)
	defer testValueBuffer.Destroy()

	ltRecipient := ltIdentity.Recipient()

	encrypted, err := secret.EncryptToRecipient(testValueBuffer, ltRecipient)
	require.NoError(t, err)

	valuePath := filepath.Join(secretDir, "value.age")
	err = afero.WriteFile(fs, valuePath, encrypted, 0o600)
	require.NoError(t, err)

	// Should fail to get with version-aware methods
	_, err = vault.GetSecret(secretName)
	require.Error(t, err)

	// List versions should return empty
	versions, err := secret.ListVersions(fs, secretDir)
	require.NoError(t, err)
	assert.Empty(t, versions)
}