banger/internal/config/config.go

package config

import (
	"os"
	"path/filepath"
	"time"

	toml "github.com/pelletier/go-toml"

	"banger/internal/model"
	"banger/internal/paths"
)

type fileConfig struct {
	RepoRoot           string `toml:"repo_root"`
	DefaultImageName   string `toml:"default_image_name"`
	DefaultBaseRootfs  string `toml:"default_base_rootfs"`
	DefaultKernel      string `toml:"default_kernel"`
	DefaultInitrd      string `toml:"default_initrd"`
	DefaultModulesDir  string `toml:"default_modules_dir"`
	DefaultPackages    string `toml:"default_packages_file"`
	AutoStopStaleAfter string `toml:"auto_stop_stale_after"`
	StatsPollInterval  string `toml:"stats_poll_interval"`
	MetricsPoll        string `toml:"metrics_poll_interval"`
	BridgeName         string `toml:"bridge_name"`
	BridgeIP           string `toml:"bridge_ip"`
	CIDR               string `toml:"cidr"`
	DefaultDNS         string `toml:"default_dns"`
}

func Load(layout paths.Layout) (model.DaemonConfig, error) {
	cfg := model.DaemonConfig{
		RepoRoot:            paths.DetectRepoRoot(),
		AutoStopStaleAfter:  0,
		StatsPollInterval:   model.DefaultStatsPollInterval,
		MetricsPollInterval: model.DefaultMetricsPollInterval,
		BridgeName:          model.DefaultBridgeName,
		BridgeIP:            model.DefaultBridgeIP,
		CIDR:                model.DefaultCIDR,
		DefaultDNS:          model.DefaultDNS,
		DefaultImageName:    "default",
	}
	if cfg.RepoRoot != "" {
		cfg.DefaultBaseRootfs = filepath.Join(cfg.RepoRoot, "rootfs.ext4")
		cfg.DefaultKernel = filepath.Join(cfg.RepoRoot, "wtf/root/boot/vmlinux-6.8.0-94-generic")
		cfg.DefaultInitrd = filepath.Join(cfg.RepoRoot, "wtf/root/boot/initrd.img-6.8.0-94-generic")
		cfg.DefaultModulesDir = filepath.Join(cfg.RepoRoot, "wtf/root/lib/modules/6.8.0-94-generic")
		cfg.DefaultPackagesFile = filepath.Join(cfg.RepoRoot, "packages.apt")
	}

	path := filepath.Join(layout.ConfigDir, "config.toml")
	info, err := os.Stat(path)
	if err != nil {
		if os.IsNotExist(err) {
			return cfg, nil
		}
		return cfg, err
	}
	if info.IsDir() {
		return cfg, nil
	}
	data, err := os.ReadFile(path)
	if err != nil {
		return cfg, err
	}
	var file fileConfig
	if err := toml.Unmarshal(data, &file); err != nil {
		return cfg, err
	}
	if file.RepoRoot != "" {
		cfg.RepoRoot = file.RepoRoot
	}
	if file.DefaultImageName != "" {
		cfg.DefaultImageName = file.DefaultImageName
	}
	if file.DefaultBaseRootfs != "" {
		cfg.DefaultBaseRootfs = file.DefaultBaseRootfs
	}
	if file.DefaultKernel != "" {
		cfg.DefaultKernel = file.DefaultKernel
	}
	if file.DefaultInitrd != "" {
		cfg.DefaultInitrd = file.DefaultInitrd
	}
	if file.DefaultModulesDir != "" {
		cfg.DefaultModulesDir = file.DefaultModulesDir
	}
	if file.DefaultPackages != "" {
		cfg.DefaultPackagesFile = file.DefaultPackages
	}
	if file.BridgeName != "" {
		cfg.BridgeName = file.BridgeName
	}
	if file.BridgeIP != "" {
		cfg.BridgeIP = file.BridgeIP
	}
	if file.CIDR != "" {
		cfg.CIDR = file.CIDR
	}
	if file.DefaultDNS != "" {
		cfg.DefaultDNS = file.DefaultDNS
	}
	if file.AutoStopStaleAfter != "" {
		duration, err := time.ParseDuration(file.AutoStopStaleAfter)
		if err != nil {
			return cfg, err
		}
		cfg.AutoStopStaleAfter = duration
	}
	if file.StatsPollInterval != "" {
		duration, err := time.ParseDuration(file.StatsPollInterval)
		if err != nil {
			return cfg, err
		}
		cfg.StatsPollInterval = duration
	}
	if file.MetricsPoll != "" {
		duration, err := time.ParseDuration(file.MetricsPoll)
		if err != nil {
			return cfg, err
		}
		cfg.MetricsPollInterval = duration
	}
	return cfg, nil
}