// Copyright 2020 The Kubernetes Authors.
// SPDX-License-Identifier: Apache-2.0

package common

import (
	"bytes"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"github.com/stretchr/testify/assert"
	"k8s.io/cli-runtime/pkg/genericclioptions"
	"sigs.k8s.io/cli-utils/pkg/testutil"
)

const (
	packageDir              = "test-pkg-dir"
	subFolder               = "sub-folder"
	inventoryFilename       = "inventory.yaml"
	secondInventoryFilename = "inventory-2.yaml"
	podAFilename            = "pod-a.yaml"
	podBFilename            = "pod-b.yaml"
	configSeparator         = "---"
)

var (
	inventoryFilePath       = filepath.Join(packageDir, inventoryFilename)
	secondInventoryFilePath = filepath.Join(packageDir, subFolder, secondInventoryFilename)
	podAFilePath            = filepath.Join(packageDir, podAFilename)
	podBFilePath            = filepath.Join(packageDir, podBFilename)
)

func setupTestFilesystem(t *testing.T) testutil.TestFilesystem {
	// Create the test filesystem, and add package config files
	// to it.
	t.Log("Creating test filesystem")
	tf := testutil.Setup(t, packageDir)
	t.Logf("Adding File: %s", inventoryFilePath)
	tf.WriteFile(t, inventoryFilePath, inventoryConfigMap)
	t.Logf("Adding File: %s", secondInventoryFilePath)
	tf.WriteFile(t, secondInventoryFilePath, secondInventoryConfigMap)
	t.Logf("Adding File: %s", podAFilePath)
	tf.WriteFile(t, podAFilePath, podA)
	t.Logf("Adding File: %s", podBFilePath)
	tf.WriteFile(t, podBFilePath, podB)
	return tf
}

var inventoryConfigMap = []byte(`
apiVersion: v1
kind: ConfigMap
metadata:
  namespace: test-namespace
  name: inventory
  labels:
    cli-utils.sigs.k8s.io/inventory-id: test-inventory
`)

var secondInventoryConfigMap = []byte(`
apiVersion: v1
kind: ConfigMap
metadata:
  namespace: test-namespace
  name: inventory-2
  labels:
    cli-utils.sigs.k8s.io/inventory-id: test-inventory
`)

var podA = []byte(`
apiVersion: v1
kind: Pod
metadata:
  name: pod-a
  namespace: test-namespace
  labels:
    name: test-pod-label
spec:
  containers:
  - name: kubernetes-pause
    image: k8s.gcr.io/pause:2.0
`)

var podB = []byte(`
apiVersion: v1
kind: Pod
metadata:
  name: pod-b
  namespace: test-namespace
  labels:
    name: test-pod-label
spec:
  containers:
  - name: kubernetes-pause
    image: k8s.gcr.io/pause:2.0
`)

func buildMultiResourceConfig(configs ...[]byte) []byte {
	r := []byte{}
	for i, config := range configs {
		if i > 0 {
			r = append(r, []byte(configSeparator)...)
		}
		r = append(r, config...)
	}
	return r
}

func TestProcessPaths(t *testing.T) {
	tf := setupTestFilesystem(t)
	defer tf.Clean()

	trueVal := true
	testCases := map[string]struct {
		paths                     []string
		expectedFileNameFlags     genericclioptions.FileNameFlags
		errFromDemandOneDirectory string
	}{
		"empty slice means reading from StdIn": {
			paths: []string{},
			expectedFileNameFlags: genericclioptions.FileNameFlags{
				Filenames: &[]string{"-"},
			},
		},
		"single file in slice is error; must be directory": {
			paths: []string{podAFilePath},
			expectedFileNameFlags: genericclioptions.FileNameFlags{
				Filenames: nil,
				Recursive: nil,
			},
			errFromDemandOneDirectory: "argument 'test-pkg-dir/pod-a.yaml' is not but must be a directory",
		},
		"single dir in slice": {
			paths: []string{tf.GetRootDir()},
			expectedFileNameFlags: genericclioptions.FileNameFlags{
				Filenames: &[]string{tf.GetRootDir()},
				Recursive: &trueVal,
			},
		},
		"multiple arguments is an error": {
			paths: []string{podAFilePath, podBFilePath},
			expectedFileNameFlags: genericclioptions.FileNameFlags{
				Filenames: nil,
				Recursive: nil,
			},
			errFromDemandOneDirectory: "specify exactly one directory path argument; rejecting [test-pkg-dir/pod-a.yaml test-pkg-dir/pod-b.yaml]",
		},
	}

	for tn, tc := range testCases {
		t.Run(tn, func(t *testing.T) {
			fileNameFlags, err := DemandOneDirectory(tc.paths)
			assert.Equal(t, tc.expectedFileNameFlags, fileNameFlags)
			if err != nil && err.Error() != tc.errFromDemandOneDirectory {
				assert.Equal(t, err.Error(), tc.errFromDemandOneDirectory)
			}
		})
	}
}

func TestFilterInputFile(t *testing.T) {
	tf := testutil.Setup(t)
	defer tf.Clean()

	testCases := map[string]struct {
		configObjects   [][]byte
		expectedObjects [][]byte
	}{
		"Empty config objects writes empty file": {
			configObjects:   [][]byte{},
			expectedObjects: [][]byte{},
		},
		"Only inventory obj writes empty file": {
			configObjects:   [][]byte{inventoryConfigMap},
			expectedObjects: [][]byte{},
		},
		"Only pods writes both pods": {
			configObjects:   [][]byte{podA, podB},
			expectedObjects: [][]byte{podA, podB},
		},
		"Basic case of inventory obj and two pods": {
			configObjects:   [][]byte{inventoryConfigMap, podA, podB},
			expectedObjects: [][]byte{podA, podB},
		},
		"Basic case of inventory obj and two pods in different order": {
			configObjects:   [][]byte{podB, inventoryConfigMap, podA},
			expectedObjects: [][]byte{podB, podA},
		},
	}
	for tn, tc := range testCases {
		t.Run(tn, func(t *testing.T) {
			// Build a single file of multiple resource configs, and
			// call the tested function FilterInputFile. This writes
			// the passed file to the test filesystem, filtering
			// the inventory object if it exists in the passed file.
			in := buildMultiResourceConfig(tc.configObjects...)
			err := FilterInputFile(bytes.NewReader(in), tf.GetRootDir())
			if err != nil {
				t.Fatalf("Unexpected error in FilterInputFile: %s", err)
			}
			// Retrieve the files from the test filesystem.
			actualFiles, err := os.ReadDir(tf.GetRootDir())
			if err != nil {
				t.Fatalf("Error reading test filesystem directory: %s", err)
			}
			// Since we remove the generated file for each test, there should
			// not be more than one file in the test filesystem.
			if len(actualFiles) > 1 {
				t.Fatalf("Wrong number of files (%d) in dir: %s", len(actualFiles), tf.GetRootDir())
			}
			// If there is a generated file, then read it into actualStr.
			actualStr := ""
			if len(actualFiles) != 0 {
				actualFilename := actualFiles[0].Name()
				defer os.Remove(actualFilename)
				actual, err := os.ReadFile(actualFilename)
				if err != nil {
					t.Fatalf("Error reading created file (%s): %s", actualFilename, err)
				}
				actualStr = strings.TrimSpace(string(actual))
			}
			// Build the expected string from the expectedObjects. This expected
			// string should not have the inventory object config in it.
			expected := buildMultiResourceConfig(tc.expectedObjects...)
			expectedStr := strings.TrimSpace(string(expected))
			if expectedStr != actualStr {
				t.Errorf("Expected file contents (%s) not equal to actual file contents (%s)",
					expectedStr, actualStr)
			}
		})
	}
}

func TestExpandDir(t *testing.T) {
	tf := setupTestFilesystem(t)
	defer tf.Clean()

	testCases := map[string]struct {
		packageDirPath    string
		expandedInventory string
		expandedPaths     []string
		isError           bool
	}{
		"empty path is error": {
			packageDirPath: "",
			isError:        true,
		},
		"path that is not dir is error": {
			packageDirPath: "fakedir1",
			isError:        true,
		},
		"root package dir excludes inventory object": {
			packageDirPath:    tf.GetRootDir(),
			expandedInventory: "inventory.yaml",
			expandedPaths: []string{
				"pod-a.yaml",
				"pod-b.yaml",
			},
			isError: false,
		},
	}

	for tn, tc := range testCases {
		t.Run(tn, func(t *testing.T) {
			actualInventory, actualPaths, err := ExpandDir(tc.packageDirPath)
			if tc.isError {
				if err == nil {
					t.Fatalf("expected error but received none")
				}
				return
			}
			if err != nil {
				t.Fatalf("received unexpected error %#v", err)
				return
			}
			actualFilename := filepath.Base(actualInventory)
			if tc.expandedInventory != actualFilename {
				t.Errorf("expected inventory template filepath (%s), got (%s)", tc.expandedInventory, actualFilename)
			}
			if len(tc.expandedPaths) != len(actualPaths) {
				t.Errorf("expected (%d) resource filepaths, got (%d)", len(tc.expandedPaths), len(actualPaths))
			}
			for _, expectedPath := range tc.expandedPaths {
				found := false
				for _, actualPath := range actualPaths {
					actualFilename := filepath.Base(actualPath)
					if expectedPath == actualFilename {
						found = true
						break
					}
				}
				if !found {
					t.Errorf("expected filename (%s) not found", expectedPath)
				}
			}
		})
	}
}

func TestExpandDirErrors(t *testing.T) {
	tf := setupTestFilesystem(t)
	defer tf.Clean()

	testCases := map[string]struct {
		packageDirPath []string
		expandedPaths  []string
		isError        bool
	}{
		"empty path is error": {
			packageDirPath: []string{},
			isError:        true,
		},
		"more than one path is error": {
			packageDirPath: []string{"fakedir1", "fakedir2"},
			isError:        true,
		},
		"path that is not dir is error": {
			packageDirPath: []string{"fakedir1"},
			isError:        true,
		},
		"root package dir excludes inventory object": {
			packageDirPath: []string{tf.GetRootDir()},
			expandedPaths: []string{
				filepath.Join(packageDir, "pod-a.yaml"),
				filepath.Join(packageDir, "pod-b.yaml"),
			},
			isError: false,
		},
	}

	for tn, tc := range testCases {
		t.Run(tn, func(t *testing.T) {
			trueVal := true
			filenameFlags := genericclioptions.FileNameFlags{
				Filenames: &tc.packageDirPath,
				Recursive: &trueVal,
			}
			actualFlags, err := ExpandPackageDir(filenameFlags)
			if tc.isError && err == nil {
				t.Fatalf("expected error but received none")
			}
			if !tc.isError {
				if err != nil {
					t.Fatalf("unexpected error received: %v", err)
				}
				actualPaths := *actualFlags.Filenames
				if len(tc.expandedPaths) != len(actualPaths) {
					t.Errorf("expected config filepaths (%s), got (%s)",
						tc.expandedPaths, actualPaths)
				}
				for _, expected := range tc.expandedPaths {
					if !filepathExists(expected, actualPaths) {
						t.Errorf("expected config filepath (%s) in actual filepaths (%s)",
							expected, actualPaths)
					}
				}
				// Check the inventory object is not in the filename flags.
				for _, actualPath := range actualPaths {
					if strings.Contains(actualPath, "inventory.yaml") {
						t.Errorf("inventory object should be excluded")
					}
				}
			}
		})
	}
}

// filepathExists returns true if the passed "filepath" is a substring
// of any of the passed full "filepaths"; false otherwise. For example:
// if filepath = "test/a.yaml", and filepaths includes "/tmp/test/a.yaml",
// this function returns true.
func filepathExists(filepath string, filepaths []string) bool {
	for _, fp := range filepaths {
		if strings.Contains(fp, filepath) {
			return true
		}
	}
	return false
}