logging, config file managment, writing library dir

backend/config/config.go

@@ -0,0 +1,106 @@
+package config
+
+import (
+	"fmt"
+	"os"
+	"path"
+	"yellowjacket/backend/library"
+
+	"github.com/BurntSushi/toml"
+)
+
+type Config struct {
+	filePath string // required
+	*configData
+}
+
+func newConfig(filePath string, data *configData) (*Config, error) {
+	// TODO make sure required fields have SOMETHING in them
+	// TODO Merge existing config with read in config
+	if data == nil {
+		data = defaultConfigData
+	}
+	return &Config{
+		filePath:   filePath,
+		configData: data,
+	}, nil
+}
+
+type configData struct {
+	Library *library.Config
+}
+
+// return errors if there is a *breaking* issue with the config
+func (d *configData) validate() error {
+	return nil
+}
+
+var defaultConfigData *configData = &configData{
+	Library: library.DefaultConfig,
+}
+
+// GetCurrentConfig will load and return the config
+// reading the config file in the user's config directory
+func GetCurrentConfig() (*Config, error) {
+	// get the config file location
+	configDir, err := GetUserConfigDirPath()
+	if err != nil {
+		return nil, fmt.Errorf("could not get user config directory path: %w", err)
+	}
+	configFilePath := path.Join(configDir, "config.toml")
+	config, err := newConfig(configFilePath, nil)
+	if err != nil {
+		return nil, fmt.Errorf("could not create new config: %w", err)
+	}
+	config.filePath = configFilePath
+
+	_, err = os.Stat(configFilePath)
+	if os.IsNotExist(err) {
+		config.WriteConfig()
+	}
+	config, err = config.loadConfig()
+	if err != nil {
+		return nil, fmt.Errorf("could not load config file %s: %w", configFilePath, err)
+	}
+	return config, nil
+}
+
+func (c *Config) loadConfig() (*Config, error) {
+	// read in the file
+	confFileData, err := os.ReadFile(c.filePath)
+	if err != nil {
+		return nil, fmt.Errorf("problem reading config file %s: %w", c.filePath, err)
+	}
+
+	// parse it into the config struct
+	var confData configData
+	_, err = toml.Decode(string(confFileData), &confData)
+	if err != nil {
+		return nil, fmt.Errorf("problem parsing config file %s: %w", c.filePath, err)
+	}
+
+	// validate the config
+	if err = confData.validate(); err != nil {
+		return nil, fmt.Errorf("invalid config file at %s: %w", c.filePath, err)
+	}
+
+	config, err := newConfig(c.filePath, &confData)
+	if err != nil {
+		return nil, fmt.Errorf("could not create config from config file data at %s: %w", c.filePath, err)
+	}
+
+	return config, nil
+}
+
+func (c *Config) WriteConfig() error {
+	confFileData, err := toml.Marshal(c)
+	if err != nil {
+		return fmt.Errorf("could not marshal config struct: %w", err)
+	}
+
+	err = os.WriteFile(c.filePath, confFileData, os.FileMode(int(0666)))
+	if err != nil {
+		return fmt.Errorf("could not write config file: %w", err)
+	}
+	return nil
+}