// Copyright (c) 2019, Sylabs Inc. All rights reserved.
// This software is licensed under a 3-clause BSD license. Please consult the
// LICENSE.md file distributed with the sources of this project regarding your
// rights to use or distribute this software.

package cmdline

import (
	"fmt"
	"reflect"
	"testing"

	"github.com/spf13/cobra"
	"github.com/sylabs/singularity/internal/pkg/test"
)

var rootCmd = &cobra.Command{Use: "root"}
var parentCmd = &cobra.Command{Use: "parent"}
var childCmd = &cobra.Command{Use: "child"}

func newCommandManager(cmd *cobra.Command) (cm *CommandManager, err error) {
	defer func() {
		if t := recover(); t != nil {
			err = fmt.Errorf("%s", t)
		}
	}()
	return NewCommandManager(cmd), nil
}

func registerCmd(cm *CommandManager, cmd *cobra.Command) (err error) {
	defer func() {
		if t := recover(); t != nil {
			err = fmt.Errorf("%s", t)
		}
	}()
	cm.RegisterCmd(cmd)
	return
}

func registerSubCmd(cm *CommandManager, parent, child *cobra.Command) (err error) {
	defer func() {
		if t := recover(); t != nil {
			err = fmt.Errorf("%s", t)
		}
	}()
	cm.RegisterSubCmd(parent, child)
	return
}

func setCmdGroup(cm *CommandManager, name string, cmds ...*cobra.Command) (err error) {
	defer func() {
		if t := recover(); t != nil {
			err = fmt.Errorf("%s", t)
		}
	}()
	cm.SetCmdGroup(name, cmds...)
	return
}

func TestCommandManager(t *testing.T) {
	test.DropPrivilege(t)
	defer test.ResetPrivilege(t)

	// check panic with nil root command
	_, err := newCommandManager(nil)
	if err == nil {
		t.Errorf("unexpected success with root nil command")
	}
	// create command manager
	cm, err := newCommandManager(rootCmd)
	if err != nil {
		t.Errorf("unexpected error while instantiating new command manager: %err", err)
	}

	// get root command
	if cm.GetRootCmd() != rootCmd {
		t.Errorf("unexpected root command returned")
	}
	// root command name must return an empty string
	if cm.GetCmdName(rootCmd) != "" {
		t.Errorf("unexpected root command name returned")
	}

	// check panic while registering a nil command
	if err := registerCmd(cm, nil); err == nil {
		t.Errorf("unexpected success with nil command")
	}

	// register parent command
	if err := registerCmd(cm, parentCmd); err != nil {
		t.Errorf("unexpected error while registering command: %s", err)
	}
	// get name with command
	if cm.GetCmdName(parentCmd) != "parent" {
		t.Errorf("unexpected command name returned")
	}
	// test with non-existent command name
	if cm.GetCmd("noparent") != nil {
		t.Errorf("unexpected command returned")
	}
	// get parent command by name
	if cm.GetCmd("parent") != parentCmd {
		t.Errorf("unexpected child command returned")
	}

	// check panic with nil parent command
	if err := registerSubCmd(cm, nil, childCmd); err == nil {
		t.Errorf("unexpected success with nil parent command")
	}
	// check panic with nil child command
	if err := registerSubCmd(cm, parentCmd, nil); err == nil {
		t.Errorf("unexpected success with nil child command")
	}
	// check panic with unregistered command
	unregisteredCmd := &cobra.Command{}
	if err := registerSubCmd(cm, unregisteredCmd, childCmd); err == nil {
		t.Errorf("unexpected success while registering sub command with unregistered parent command")
	}

	// register child command for parent command
	if err := registerSubCmd(cm, parentCmd, childCmd); err != nil {
		t.Errorf("unexpected error while registering command: %s", err)
	}
	// get child command by name
	if cm.GetCmd("parent_child") != childCmd {
		t.Errorf("unexpected child command returned")
	}

	// check panic by creating a group with nil command only
	emptyGroup := []*cobra.Command{nil, nil}
	if err := setCmdGroup(cm, "test", emptyGroup...); err == nil {
		t.Errorf("unexpected success while creating group with nil command")
	}

	// create group test with a nil command
	testGroup := []*cobra.Command{parentCmd, childCmd}
	if err := setCmdGroup(cm, "test", testGroup...); err != nil {
		t.Errorf("unexpected error while creating group command: %s", err)
	}
	// check panic by adding an already existing group
	if err := setCmdGroup(cm, "test", testGroup...); err == nil {
		t.Errorf("unexpected success while creating an existing group")
	}

	// check returned command group
	cmdGroup := cm.GetCmdGroup("test")
	if !reflect.DeepEqual(testGroup, cmdGroup) {
		t.Errorf("unexpected group command returned")
	}

	// check get command by name
	if cm.GetCmd("test") != nil {
		t.Errorf("unexpected test command returned")
	}
}