71: Allow user to change config options at runtime

There is a LoadConf and a LoadConfFromFile.
LoadConfFromFile reads the iniFile into memory and and calls
LoadConf, which executes the old parsing commands from
LoadConf (old func).

The remaining of the LoadConfFromFile is the same as the old OldConf.

aerc.go

@@ -121,7 +121,7 @@ func main() {
 	logger = log.New(logOut, "", log.LstdFlags)
 	logger.Println("Starting up aerc")
 
-	conf, err := config.LoadConfig(nil, ShareDir)
+	conf, err := config.LoadConfigFromFile(nil, ShareDir)
 	if err != nil {
 		fmt.Printf("Failed to load config: %v\n", err)
 		os.Exit(1)

commands/set.go

@@ -0,0 +1,69 @@
+package commands
+
+import (
+	"errors"
+	"strings"
+
+	"git.sr.ht/~sircmpwn/aerc/widgets"
+
+	"github.com/go-ini/ini"
+)
+
+type Set struct{}
+
+func setUsage() string {
+	return "set <category>.<option> <value>"
+}
+
+func init() {
+	register(Set{})
+}
+
+func (_ Set) Aliases() []string {
+	return []string{"set"}
+
+}
+
+func (_ Set) Complete(aerc *widgets.Aerc, args []string) []string {
+	return nil
+}
+
+func SetCore(aerc *widgets.Aerc, args []string) error {
+	if len(args) != 3 {
+		return errors.New("Usage: " + setUsage())
+	}
+
+	config := aerc.Config()
+
+	parameters := strings.Split(args[1], ".")
+
+	if len(parameters) != 2 {
+		return errors.New("Usage: " + setUsage())
+	}
+
+	category := parameters[0]
+	option := parameters[1]
+	value := args[2]
+
+	new_file := ini.Empty()
+
+	section, err := new_file.NewSection(category)
+
+	if err != nil {
+		return nil
+	}
+
+	if _, err := section.NewKey(option, value); err != nil {
+		return err
+	}
+
+	if err := config.LoadConfig(new_file); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (_ Set) Execute(aerc *widgets.Aerc, args []string) error {
+	return SetCore(aerc, args)
+}

config/config.go

@@ -222,7 +222,61 @@ func installTemplate(root, sharedir, name string) error {
 	return nil
 }
 
-func LoadConfig(root *string, sharedir string) (*AercConfig, error) {
+func (config *AercConfig) LoadConfig(file *ini.File) error {
+	if filters, err := file.GetSection("filters"); err == nil {
+		// TODO: Parse the filter more finely, e.g. parse the regex
+		for _, match := range filters.KeyStrings() {
+			cmd := filters.KeysHash()[match]
+			filter := FilterConfig{
+				Command: cmd,
+				Filter:  match,
+			}
+			if strings.Contains(match, ",~") {
+				filter.FilterType = FILTER_HEADER
+				header := filter.Filter[:strings.Index(filter.Filter, ",")]
+				regex := filter.Filter[strings.Index(filter.Filter, "~")+1:]
+				filter.Header = strings.ToLower(header)
+				filter.Regex, err = regexp.Compile(regex)
+				if err != nil {
+					panic(err)
+				}
+			} else if strings.ContainsRune(match, ',') {
+				filter.FilterType = FILTER_HEADER
+				header := filter.Filter[:strings.Index(filter.Filter, ",")]
+				value := filter.Filter[strings.Index(filter.Filter, ",")+1:]
+				filter.Header = strings.ToLower(header)
+				filter.Regex, err = regexp.Compile(regexp.QuoteMeta(value))
+			} else {
+				filter.FilterType = FILTER_MIMETYPE
+			}
+			config.Filters = append(config.Filters, filter)
+		}
+	}
+	if viewer, err := file.GetSection("viewer"); err == nil {
+		if err := viewer.MapTo(&config.Viewer); err != nil {
+			return err
+		}
+		for key, val := range viewer.KeysHash() {
+			switch key {
+			case "alternatives":
+				config.Viewer.Alternatives = strings.Split(val, ",")
+			}
+		}
+	}
+	if compose, err := file.GetSection("compose"); err == nil {
+		if err := compose.MapTo(&config.Compose); err != nil {
+			return err
+		}
+	}
+	if ui, err := file.GetSection("ui"); err == nil {
+		if err := ui.MapTo(&config.Ui); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func LoadConfigFromFile(root *string, sharedir string) (*AercConfig, error) {
 	if root == nil {
 		_root := path.Join(xdg.ConfigHome(), "aerc")
 		root = &_root
@@ -274,61 +328,16 @@ func LoadConfig(root *string, sharedir string) (*AercConfig, error) {
 	}
 	quit, _ := ParseBinding("<C-q>", ":quit<Enter>")
 	config.Bindings.AccountWizard.Add(quit)
-	if filters, err := file.GetSection("filters"); err == nil {
-		// TODO: Parse the filter more finely, e.g. parse the regex
-		for _, match := range filters.KeyStrings() {
-			cmd := filters.KeysHash()[match]
-			filter := FilterConfig{
-				Command: cmd,
-				Filter:  match,
-			}
-			if strings.Contains(match, ",~") {
-				filter.FilterType = FILTER_HEADER
-				header := filter.Filter[:strings.Index(filter.Filter, ",")]
-				regex := filter.Filter[strings.Index(filter.Filter, "~")+1:]
-				filter.Header = strings.ToLower(header)
-				filter.Regex, err = regexp.Compile(regex)
-				if err != nil {
-					panic(err)
-				}
-			} else if strings.ContainsRune(match, ',') {
-				filter.FilterType = FILTER_HEADER
-				header := filter.Filter[:strings.Index(filter.Filter, ",")]
-				value := filter.Filter[strings.Index(filter.Filter, ",")+1:]
-				filter.Header = strings.ToLower(header)
-				filter.Regex, err = regexp.Compile(regexp.QuoteMeta(value))
-			} else {
-				filter.FilterType = FILTER_MIMETYPE
-			}
-			config.Filters = append(config.Filters, filter)
-		}
-	}
-	if viewer, err := file.GetSection("viewer"); err == nil {
-		if err := viewer.MapTo(&config.Viewer); err != nil {
+
+	if err = config.LoadConfig(file); err != nil {
 		return nil, err
 	}
-		for key, val := range viewer.KeysHash() {
-			switch key {
-			case "alternatives":
-				config.Viewer.Alternatives = strings.Split(val, ",")
-			}
-		}
-	}
-	if compose, err := file.GetSection("compose"); err == nil {
-		if err := compose.MapTo(&config.Compose); err != nil {
-			return nil, err
-		}
-	}
-	if ui, err := file.GetSection("ui"); err == nil {
-		if err := ui.MapTo(&config.Ui); err != nil {
-			return nil, err
-		}
-	}
 	if ui, err := file.GetSection("general"); err == nil {
 		if err := ui.MapTo(&config.General); err != nil {
 			return nil, err
 		}
 	}
+
 	accountsPath := path.Join(*root, "accounts.conf")
 	if accounts, err := loadAccountConfig(accountsPath); err != nil {
 		return nil, err