// Copyright The OpenTelemetry 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.

// +build linux

package processscraper

import (
	"github.com/shirou/gopsutil/cpu"

	"go.opentelemetry.io/collector/model/pdata"
	"go.opentelemetry.io/collector/receiver/hostmetricsreceiver/internal/metadata"
)

const cpuStatesLen = 3

func appendCPUTimeStateDataPoints(ddps pdata.NumberDataPointSlice, startTime, now pdata.Timestamp, cpuTime *cpu.TimesStat) {
	initializeCPUTimeDataPoint(ddps.AppendEmpty(), startTime, now, cpuTime.User, metadata.LabelProcessState.User)
	initializeCPUTimeDataPoint(ddps.AppendEmpty(), startTime, now, cpuTime.System, metadata.LabelProcessState.System)
	initializeCPUTimeDataPoint(ddps.AppendEmpty(), startTime, now, cpuTime.Iowait, metadata.LabelProcessState.Wait)
}

func initializeCPUTimeDataPoint(dataPoint pdata.NumberDataPoint, startTime, now pdata.Timestamp, value float64, stateLabel string) {
	dataPoint.Attributes().InsertString(metadata.Labels.ProcessState, stateLabel)
	dataPoint.SetStartTimestamp(startTime)
	dataPoint.SetTimestamp(now)
	dataPoint.SetDoubleVal(value)
}

func getProcessExecutable(proc processHandle) (*executableMetadata, error) {
	name, err := proc.Name()
	if err != nil {
		return nil, err
	}

	exe, err := proc.Exe()
	if err != nil {
		return nil, err
	}

	executable := &executableMetadata{name: name, path: exe}
	return executable, nil
}

func getProcessCommand(proc processHandle) (*commandMetadata, error) {
	cmdline, err := proc.CmdlineSlice()
	if err != nil {
		return nil, err
	}

	var cmd string
	if len(cmdline) > 0 {
		cmd = cmdline[0]
	}

	command := &commandMetadata{command: cmd, commandLineSlice: cmdline}
	return command, nil
}
