package main

import (
	"log"
	"os"
	"path"

	"github.com/BurntSushi/toml"
)

const (
	configPath = "/etc/nvidia-container-runtime/config.toml"
	driverPath = "/run/nvidia/driver"
)

var defaultPaths = [...]string{
	path.Join(driverPath, configPath),
	configPath,
}

// CLIConfig : options for nvidia-container-cli.
type CLIConfig struct {
	Root                            *string  `toml:"root"`
	Path                            *string  `toml:"path"`
	Environment                     []string `toml:"environment"`
	Debug                           *string  `toml:"debug"`
	Ldcache                         *string  `toml:"ldcache"`
	LoadKmods                       bool     `toml:"load-kmods"`
	NoPivot                         bool     `toml:"no-pivot"`
	NoCgroups                       bool     `toml:"no-cgroups"`
	User                            *string  `toml:"user"`
	Ldconfig                        *string  `toml:"ldconfig"`
	AlphaMergeVisibleDevicesEnvvars bool     `toml:"alpha-merge-visible-devices-envvars"`
}

// HookConfig : options for the nvidia-container-toolkit.
type HookConfig struct {
	DisableRequire bool    `toml:"disable-require"`
	SwarmResource  *string `toml:"swarm-resource"`

	NvidiaContainerCLI CLIConfig `toml:"nvidia-container-cli"`
}

func getDefaultHookConfig() (config HookConfig) {
	return HookConfig{
		DisableRequire: false,
		SwarmResource:  nil,
		NvidiaContainerCLI: CLIConfig{
			Root:                            nil,
			Path:                            nil,
			Environment:                     []string{},
			Debug:                           nil,
			Ldcache:                         nil,
			LoadKmods:                       true,
			NoPivot:                         false,
			NoCgroups:                       false,
			User:                            nil,
			Ldconfig:                        nil,
			AlphaMergeVisibleDevicesEnvvars: false,
		},
	}
}

func getHookConfig() (config HookConfig) {
	var err error

	if len(*configflag) > 0 {
		config = getDefaultHookConfig()
		_, err = toml.DecodeFile(*configflag, &config)
		if err != nil {
			log.Panicln("couldn't open configuration file:", err)
		}
	} else {
		for _, p := range defaultPaths {
			config = getDefaultHookConfig()
			_, err = toml.DecodeFile(p, &config)
			if err == nil {
				break
			} else if !os.IsNotExist(err) {
				log.Panicln("couldn't open default configuration file:", err)
			}
		}
	}

	return config
}