// Copyright 2020 The gVisor 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 tools

import (
	"fmt"
	"net"
	"regexp"
	"strconv"
	"testing"
)

// Redis is for the client 'redis-benchmark'.
type Redis struct {
	Operation string
}

// MakeCmd returns a redis-benchmark client command.
func (r *Redis) MakeCmd(ip net.IP, port, requests int) []string {
	// There is no -t PING_BULK for redis-benchmark, so adjust the command in that case.
	// Note that "ping" will run both PING_INLINE and PING_BULK.
	if r.Operation == "PING_BULK" {
		return []string{
			"redis-benchmark",
			"--csv",
			"-t", "ping",
			"-h", ip.String(),
			"-p", fmt.Sprintf("%d", port),
			"-n", fmt.Sprintf("%d", requests),
		}
	}

	// runs redis-benchmark -t operation for 100K requests against server.
	return []string{
		"redis-benchmark",
		"--csv",
		"-t", r.Operation,
		"-h", ip.String(),
		"-p", fmt.Sprintf("%d", port),
		"-n", fmt.Sprintf("%d", requests),
	}
}

// Report parses output from redis-benchmark client and reports metrics.
func (r *Redis) Report(b *testing.B, output string) {
	b.Helper()
	result, err := r.parseOperation(output)
	if err != nil {
		b.Fatalf("parsing result %s failed with err: %v", output, err)
	}
	ReportCustomMetric(b, result, r.Operation /*metric_name*/, "QPS" /*unit*/)
}

// parseOperation grabs the metric operations per second from redis-benchmark output.
func (r *Redis) parseOperation(data string) (float64, error) {
	re := regexp.MustCompile(fmt.Sprintf(`"%s( .*)?","(\d*\.\d*)"`, r.Operation))
	match := re.FindStringSubmatch(data)
	if len(match) < 3 {
		return 0.0, fmt.Errorf("could not find %s in %s", r.Operation, data)
	}
	return strconv.ParseFloat(match[2], 64)
}