// This file is part of MinIO Console Server
// Copyright (c) 2020 MinIO, Inc.
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

package restapi

import (
	"bytes"
	"context"
	"io"
	"testing"

	"errors"

	"github.com/minio/mcs/models"
	"github.com/minio/minio/pkg/madmin"
	"github.com/stretchr/testify/assert"
)

var minioStartProfiling func(profiler madmin.ProfilerType) ([]madmin.StartProfilingResult, error)
var minioStopProfiling func() (io.ReadCloser, error)

// mock function of startProfiling()
func (ac adminClientMock) startProfiling(ctx context.Context, profiler madmin.ProfilerType) ([]madmin.StartProfilingResult, error) {
	return minioStartProfiling(profiler)
}

// mock function of stopProfiling()
func (ac adminClientMock) stopProfiling(ctx context.Context) (io.ReadCloser, error) {
	return minioStopProfiling()
}

func TestStartProfiling(t *testing.T) {
	ctx := context.Background()
	assert := assert.New(t)
	adminClient := adminClientMock{}
	// Test-1 : startProfiling() Get response from Minio server with one profiling object
	// mock function response from startProfiling()
	minioStartProfiling = func(profiler madmin.ProfilerType) ([]madmin.StartProfilingResult, error) {
		return []madmin.StartProfilingResult{
			{
				NodeName: "http://127.0.0.1:9000/",
				Success:  true,
				Error:    "",
			},
			{
				NodeName: "http://127.0.0.1:9001/",
				Success:  true,
				Error:    "",
			},
		}, nil
	}
	function := "startProfiling()"
	cpuProfiler := models.ProfilerType("cpu")
	startProfilingResults, err := startProfiling(ctx, adminClient, cpuProfiler)
	if err != nil {
		t.Errorf("Failed on %s:, error occurred: %s", function, err.Error())
	}
	assert.Equal(2, len(startProfilingResults))
	//Test-2 : startProfiling() Correctly handles errors returned by Minio
	//mock function response from startProfiling()
	minioStartProfiling = func(profiler madmin.ProfilerType) ([]madmin.StartProfilingResult, error) {
		return nil, errors.New("error")
	}
	_, err = startProfiling(ctx, adminClient, cpuProfiler)
	if assert.Error(err) {
		assert.Equal("error", err.Error())
	}
}

// Implementing fake closingBuffer need it to mock stopProfiling() (io.ReadCloser, error)
type ClosingBuffer struct {
	*bytes.Buffer
}

// Implementing a fake Close function for io.ReadCloser
func (cb *ClosingBuffer) Close() error {
	return nil
}

func TestStopProfiling(t *testing.T) {
	ctx := context.Background()
	assert := assert.New(t)
	adminClient := adminClientMock{}
	// Test-1 : stopProfiling() Get response from Minio server and that response is a readCloser interface
	// mock function response from startProfiling()
	minioStopProfiling = func() (io.ReadCloser, error) {
		return &ClosingBuffer{bytes.NewBufferString("In memory string eaeae")}, nil
	}
	function := "stopProfiling()"
	readCloserInterface, err := stopProfiling(ctx, adminClient)
	if err != nil {
		t.Errorf("Failed on %s:, error occurred: %s", function, err.Error())
	}
	// Check return type of stopProfiling is io.ReadCloser by doing a cast
	assert.NotPanics(func() { readCloserInterface.(io.ReadCloser).Close() })
	// Test-2 : stopProfiling() Correctly handles errors returned by Minio
	// mock function response from stopProfiling()
	minioStopProfiling = func() (io.ReadCloser, error) {
		return nil, errors.New("error")
	}
	_, err = stopProfiling(ctx, adminClient)
	if assert.Error(err) {
		assert.Equal("error", err.Error())
	}
}