package filesystem

import (
	"bytes"
	"context"
	"io"
	"os"
	"path/filepath"
	"testing"
)

func TestNewFileSystemStore(t *testing.T) {
	// Create a temporary directory for tests
	tempDir, err := os.MkdirTemp("", "agate-test-*")
	if err != nil {
		t.Fatalf("Failed to create temp directory: %v", err)
	}
	defer os.RemoveAll(tempDir) // Clean up after test

	// Create a new store
	store, err := NewFileSystemStore(tempDir)
	if err != nil {
		t.Fatalf("Failed to create filesystem store: %v", err)
	}

	// Check that directories were created
	if _, err := os.Stat(tempDir); os.IsNotExist(err) {
		t.Fatalf("Base directory was not created")
	}

	// Check that the store's base directory matches the expected path
	if store.GetBaseDir() != tempDir {
		t.Fatalf("Store base directory does not match: got %s, want %s", store.GetBaseDir(), tempDir)
	}

	activeDir := filepath.Join(tempDir, "active")
	if _, err := os.Stat(activeDir); os.IsNotExist(err) {
		t.Fatalf("Active directory was not created")
	}

	// Check that the store's active directory matches the expected path
	if store.GetActiveDir() != activeDir {
		t.Fatalf("Store active directory does not match: got %s, want %s", store.GetActiveDir(), activeDir)
	}
}

func TestStoreAndRetrieveBlob(t *testing.T) {
	// Create a temporary directory for tests
	tempDir, err := os.MkdirTemp("", "agate-test-*")
	if err != nil {
		t.Fatalf("Failed to create temp directory: %v", err)
	}
	defer os.RemoveAll(tempDir) // Clean up after test

	// Create a new store
	store, err := NewFileSystemStore(tempDir)
	if err != nil {
		t.Fatalf("Failed to create filesystem store: %v", err)
	}

	// Create test data
	testData := []byte("test data for blob")
	reader := bytes.NewReader(testData)
	ctx := context.Background()

	// Store the blob
	snapshotID := "test-snapshot-id"
	path, err := store.StoreBlob(ctx, snapshotID, reader)
	if err != nil {
		t.Fatalf("Failed to store blob: %v", err)
	}

	// Check that the file was created
	if _, err := os.Stat(path); os.IsNotExist(err) {
		t.Fatalf("Blob file was not created")
	}

	// Retrieve the blob
	blobReader, err := store.RetrieveBlob(ctx, snapshotID)
	if err != nil {
		t.Fatalf("Failed to retrieve blob: %v", err)
	}
	defer blobReader.Close()

	// Read the data
	retrievedData, err := io.ReadAll(blobReader)
	if err != nil {
		t.Fatalf("Failed to read blob data: %v", err)
	}

	// Check that the data matches
	if !bytes.Equal(testData, retrievedData) {
		t.Fatalf("Retrieved data does not match original data")
	}
}

func TestDeleteBlob(t *testing.T) {
	// Create a temporary directory for tests
	tempDir, err := os.MkdirTemp("", "agate-test-*")
	if err != nil {
		t.Fatalf("Failed to create temp directory: %v", err)
	}
	defer os.RemoveAll(tempDir) // Clean up after test

	// Create a new store
	store, err := NewFileSystemStore(tempDir)
	if err != nil {
		t.Fatalf("Failed to create filesystem store: %v", err)
	}

	// Create test data
	testData := []byte("test data for blob")
	reader := bytes.NewReader(testData)
	ctx := context.Background()

	// Store the blob
	snapshotID := "test-snapshot-id"
	path, err := store.StoreBlob(ctx, snapshotID, reader)
	if err != nil {
		t.Fatalf("Failed to store blob: %v", err)
	}

	// Delete the blob
	err = store.DeleteBlob(ctx, snapshotID)
	if err != nil {
		t.Fatalf("Failed to delete blob: %v", err)
	}

	// Check that the file was deleted
	if _, err := os.Stat(path); !os.IsNotExist(err) {
		t.Fatalf("Blob file was not deleted")
	}

	// Deleting a non-existent blob should not return an error
	err = store.DeleteBlob(ctx, "non-existent-id")
	if err != nil {
		t.Fatalf("DeleteBlob returned an error for non-existent blob: %v", err)
	}
}

func TestGetBlobPath(t *testing.T) {
	// Create a temporary directory for tests
	tempDir, err := os.MkdirTemp("", "agate-test-*")
	if err != nil {
		t.Fatalf("Failed to create temp directory: %v", err)
	}
	defer os.RemoveAll(tempDir) // Clean up after test

	// Create a new store
	store, err := NewFileSystemStore(tempDir)
	if err != nil {
		t.Fatalf("Failed to create filesystem store: %v", err)
	}

	// Create test data
	testData := []byte("test data for blob")
	reader := bytes.NewReader(testData)
	ctx := context.Background()

	// Store the blob
	snapshotID := "test-snapshot-id"
	expectedPath, err := store.StoreBlob(ctx, snapshotID, reader)
	if err != nil {
		t.Fatalf("Failed to store blob: %v", err)
	}

	// Get the blob path
	path, err := store.GetBlobPath(ctx, snapshotID)
	if err != nil {
		t.Fatalf("Failed to get blob path: %v", err)
	}

	// Check that the path matches
	if path != expectedPath {
		t.Fatalf("GetBlobPath returned incorrect path: got %s, want %s", path, expectedPath)
	}

	// Getting path for non-existent blob should return ErrNotFound
	_, err = store.GetBlobPath(ctx, "non-existent-id")
	if err == nil {
		t.Fatalf("GetBlobPath did not return an error for non-existent blob")
	}
}

func TestCleanActiveDir(t *testing.T) {
	// Create a temporary directory for tests
	tempDir, err := os.MkdirTemp("", "agate-test-*")
	if err != nil {
		t.Fatalf("Failed to create temp directory: %v", err)
	}
	defer os.RemoveAll(tempDir) // Clean up after test

	// Create a new store
	store, err := NewFileSystemStore(tempDir)
	if err != nil {
		t.Fatalf("Failed to create filesystem store: %v", err)
	}

	// Get the active directory
	activeDir := store.GetActiveDir()

	// Create some test files in the active directory
	testFile1 := filepath.Join(activeDir, "test1.txt")
	testFile2 := filepath.Join(activeDir, "test2.txt")

	if err := os.WriteFile(testFile1, []byte("test1"), 0644); err != nil {
		t.Fatalf("Failed to create test file: %v", err)
	}
	if err := os.WriteFile(testFile2, []byte("test2"), 0644); err != nil {
		t.Fatalf("Failed to create test file: %v", err)
	}

	// Clean the active directory
	ctx := context.Background()
	err = store.CleanActiveDir(ctx)
	if err != nil {
		t.Fatalf("Failed to clean active directory: %v", err)
	}

	// Check that the files were deleted
	entries, err := os.ReadDir(activeDir)
	if err != nil {
		t.Fatalf("Failed to read active directory: %v", err)
	}
	if len(entries) > 0 {
		t.Fatalf("Active directory was not cleaned, %d files remain", len(entries))
	}
}