package internal

import (
	"fmt"
	"strings"
)

type Platform string

const (
	LinuxArmV7 Platform = "linux/arm/v7"
	LinuxArmV6 Platform = "linux/arm/v6"
	LinuxArm64 Platform = "linux/arm64"
	LinuxAmd64 Platform = "linux/amd64"
)

type Platforms []Platform

var AllPlatforms = Platforms{LinuxArmV7, LinuxArmV6, LinuxArm64, LinuxAmd64}

type PlatformsValue struct {
	*Platforms
	changed bool
}

var isIncluded = func(opts Platforms, val Platform) bool {
	for _, opt := range opts {
		if val == opt {
			return true
		}
	}
	return false
}

// Append adds the specified value to the end of the flag value list.
func (platforms *PlatformsValue) Append(value string) error {
	if !isIncluded(AllPlatforms, Platform(value)) {
		return fmt.Errorf("%s is not included in %s", value, AllPlatforms.Join(", "))
	}
	*platforms.Platforms = append(*platforms.Platforms, Platform(value))
	return nil
}

// Replace will fully overwrite any data currently in the flag value list.
func (platforms *PlatformsValue) Replace(values []string) error {
	*platforms.Platforms = []Platform{}
	for _, value := range values {
		if !isIncluded(AllPlatforms, Platform(value)) {
			return fmt.Errorf("%s is not included in %s", value, AllPlatforms.Join(", "))
		}
		*platforms.Platforms = append(*platforms.Platforms, Platform(value))
	}
	return nil
}

// GetSlice returns the flag value list as an array of strings.
func (platforms *PlatformsValue) GetSlice() []string {
	var platformsStr []string
	for _, platform := range *platforms.Platforms {
		platformsStr = append(platformsStr, string(platform))
	}
	return platformsStr
}

func (platforms PlatformsValue) String() string {
	return "[" + platforms.Platforms.Join(",") + "]"
}

func (platforms *PlatformsValue) Set(values string) error {
	var valuesP []Platform
	for _, value := range strings.Split(values, ",") {
		valueP := Platform(value)
		if !isIncluded(AllPlatforms, valueP) {
			return fmt.Errorf("%s is not included in %s", value, AllPlatforms.Join(", "))
		}
		if !platforms.changed || !isIncluded(*platforms.Platforms, valueP) {
			valuesP = append(valuesP, valueP)
		}
	}

	if !platforms.changed {
		*platforms.Platforms = valuesP
		platforms.changed = true
	} else {
		*platforms.Platforms = append(*platforms.Platforms, valuesP...)
	}
	return nil
}

func (platforms *PlatformsValue) Type() string {
	return "platformSlice"
}

func (platforms *Platforms) Join(sep string) string {
	value := PlatformsValue{Platforms: platforms}
	return strings.Join(value.GetSlice(), sep)
}