// Copyright (c) 2019, the Drone Plugins project authors.
// Please see the AUTHORS file for details. All rights reserved.
// Use of this source code is governed by an Apache 2.0 license that can be
// found in the LICENSE file.

package plugin

import (
	"os"
	"strconv"
	"strings"
	"time"
)

// List of enviornment variables set by Drone when running a step within a
// build stage.
//
// Multiple values are specified with `,` within the string. If there are
// multiple values this is to support backward compatibility with versions of
// Drone prior to the 1.0 release.

const (
	//---------------------------------------------------------------------
	// Stage Enviornment Variables
	//---------------------------------------------------------------------

	// StageArchEnvVar corresponds to Stage.Arch.
	StageArchEnvVar = "DRONE_STAGE_ARCH"
	// StageDependsOnEnvVar corresponds to Stage.DependsOn.
	StageDependsOnEnvVar = "DRONE_STAGE_DEPENDS_ON"
	// StageFinishedEnvVar corresponds to Stage.Finished.
	StageFinishedEnvVar = "DRONE_STAGE_FINISHED"
	// StageKindEnvVar corresponds Stage.Kind.
	StageKindEnvVar = "DRONE_STAGE_KIND"
	// StageMachineEnvVar corresponds to Stage.Machine.
	StageMachineEnvVar = "DRONE_STAGE_MACHINE"
	// StageNameEnvVar corresponds to Stage.Name.
	StageNameEnvVar = "DRONE_STAGE_NAME"
	// StageNumberEnvVar corresponds to Stage.Number.
	StageNumberEnvVar = "DRONE_STAGE_NUMBER"
	// StageOSEnvVar corresponds to Stage.OS.
	StageOSEnvVar = "DRONE_STAGE_OS"
	// StageStartedEnvVar corresponds to Stage.Started.
	StageStartedEnvVar = "DRONE_STAGE_STARTED"
	// StageStatusEnvVar corresponds to Stage.Status.
	StageStatusEnvVar = "DRONE_STAGE_STATUS"
	// StageTypeEnvVar corresponds to Stage.Type.
	StageTypeEnvVar = "DRONE_STAGE_TYPE"
	// StageVariantEnvVar corresponds to Stage.Variant.
	StageVariantEnvVar = "DRONE_STAGE_VARIANT"
	// StageVersionEnvVar corresponds to Stage.Version.
	StageVersionEnvVar = "DRONE_STAGE_VERSION"

	//---------------------------------------------------------------------
	// Step Environment Variables
	//---------------------------------------------------------------------

	// StepNameEnvVar corresponds to Step.Name.
	StepNameEnvVar = "DRONE_STEP_NAME"
	// StepNumberEnvVar corresponds to Step.Number.
	StepNumberEnvVar = "DRONE_STEP_NUMBER"
)

// StringEnvVar gets the environment variable's value.
//
// If the value is not present then this returns the empty string.
func StringEnvVar(envVar string) string {
	return envVarValue(envVar)
}

// StringSliceEnvVar gets the environment variable as a string slice.
//
// If the value is not present then this returns an empty slice.
func StringSliceEnvVar(envVar string) []string {
	return strings.Split(envVarValue(envVar), ",")
}

// IntEnvVar gets the environment variable as an int.
//
// If the value is not present then this returns 0.
func IntEnvVar(envVar string) int {
	return int(Int64EnvVar(envVar))
}

// Int64EnvVar gets the environment variable as an int64.
//
// If the value is not present then this returns 0.
func Int64EnvVar(envVar string) int64 {
	value, err := strconv.ParseInt(envVarValue(envVar), 0, 64)

	if err != nil {
		return 0
	}

	return value
}

// UintEnvVar gets the environment variable as an uint.
//
// If the value is not present then this returns 0.
func UintEnvVar(envVar string) uint {
	return uint(Uint64EnvVar(envVar))
}

// Uint64EnvVar gets the environment variable as an uint64.
//
// If the value is not present then this returns 0.
func Uint64EnvVar(envVar string) uint64 {
	value, err := strconv.ParseUint(envVarValue(envVar), 0, 64)

	if err != nil {
		return 0
	}

	return value
}

// BoolEnvVar gets the environment variable as a bool.
//
// If the value is not present then this returns false.
func BoolEnvVar(envVar string) bool {
	value, err := strconv.ParseBool(envVarValue(envVar))

	if err != nil {
		return false
	}

	return value
}

// TimeEnvVar gets the environment variable as a Time created from a unix
// timestamp.
//
// If the value is not present then this returns time.Unix(0).
func TimeEnvVar(envVar string) time.Time {
	return time.Unix(Int64EnvVar(envVar), 0)
}

// envVarValue returns the first matched environment variable or the empty
// string if none was found.
func envVarValue(envVar string) string {
	return os.Getenv(envVar)
}