/*
Copyright 2017 The Kubernetes Authors.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package testingexec

import (
	"context"
	"fmt"
	"io"

	"k8s.io/utils/exec"
)

// A simple scripted Interface type.
type FakeExec struct {
	CommandScript []FakeCommandAction
	CommandCalls  int
	LookPathFunc  func(string) (string, error)
}

var _ exec.Interface = &FakeExec{}

type FakeCommandAction func(cmd string, args ...string) exec.Cmd

func (fake *FakeExec) Command(cmd string, args ...string) exec.Cmd {
	if fake.CommandCalls > len(fake.CommandScript)-1 {
		panic(fmt.Sprintf("ran out of Command() actions. Could not handle command [%d]: %s args: %v", fake.CommandCalls, cmd, args))
	}
	i := fake.CommandCalls
	fake.CommandCalls++
	return fake.CommandScript[i](cmd, args...)
}

func (fake *FakeExec) CommandContext(ctx context.Context, cmd string, args ...string) exec.Cmd {
	return fake.Command(cmd, args...)
}

func (fake *FakeExec) LookPath(file string) (string, error) {
	return fake.LookPathFunc(file)
}

// A simple scripted Cmd type.
type FakeCmd struct {
	Argv                 []string
	CombinedOutputScript []FakeCombinedOutputAction
	CombinedOutputCalls  int
	CombinedOutputLog    [][]string
	RunScript            []FakeRunAction
	RunCalls             int
	RunLog               [][]string
	Dirs                 []string
	Stdin                io.Reader
	Stdout               io.Writer
	Stderr               io.Writer
}

var _ exec.Cmd = &FakeCmd{}

func InitFakeCmd(fake *FakeCmd, cmd string, args ...string) exec.Cmd {
	fake.Argv = append([]string{cmd}, args...)
	return fake
}

type FakeCombinedOutputAction func() ([]byte, error)
type FakeRunAction func() ([]byte, []byte, error)

func (fake *FakeCmd) SetDir(dir string) {
	fake.Dirs = append(fake.Dirs, dir)
}

func (fake *FakeCmd) SetStdin(in io.Reader) {
	fake.Stdin = in
}

func (fake *FakeCmd) SetStdout(out io.Writer) {
	fake.Stdout = out
}

func (fake *FakeCmd) SetStderr(out io.Writer) {
	fake.Stderr = out
}

func (fake *FakeCmd) Run() error {
	if fake.RunCalls > len(fake.RunScript)-1 {
		panic("ran out of Run() actions")
	}
	if fake.RunLog == nil {
		fake.RunLog = [][]string{}
	}
	i := fake.RunCalls
	fake.RunLog = append(fake.RunLog, append([]string{}, fake.Argv...))
	fake.RunCalls++
	stdout, stderr, err := fake.RunScript[i]()
	if stdout != nil {
		fake.Stdout.Write(stdout)
	}
	if stderr != nil {
		fake.Stderr.Write(stderr)
	}
	return err
}

func (fake *FakeCmd) CombinedOutput() ([]byte, error) {
	if fake.CombinedOutputCalls > len(fake.CombinedOutputScript)-1 {
		panic("ran out of CombinedOutput() actions")
	}
	if fake.CombinedOutputLog == nil {
		fake.CombinedOutputLog = [][]string{}
	}
	i := fake.CombinedOutputCalls
	fake.CombinedOutputLog = append(fake.CombinedOutputLog, append([]string{}, fake.Argv...))
	fake.CombinedOutputCalls++
	return fake.CombinedOutputScript[i]()
}

func (fake *FakeCmd) Output() ([]byte, error) {
	return nil, fmt.Errorf("unimplemented")
}

func (fake *FakeCmd) Stop() {
	// no-op
}

// A simple fake ExitError type.
type FakeExitError struct {
	Status int
}

var _ exec.ExitError = FakeExitError{}

func (fake FakeExitError) String() string {
	return fmt.Sprintf("exit %d", fake.Status)
}

func (fake FakeExitError) Error() string {
	return fake.String()
}

func (fake FakeExitError) Exited() bool {
	return true
}

func (fake FakeExitError) ExitStatus() int {
	return fake.Status
}