config: rework contextual sections implementation

The current contextual binds and ui config API is awkward and cumbersome
to use. Rework it to make it more elegant.

Store the contextual sections as private fields of the UIConfig and
KeyBindings structures. Add cache to avoid recomputation of the composed
UIConfig and KeyBindings objects every time a contextual item is
requested. Replace the cache from DirectoryList with that.

Signed-off-by: Robin Jarry <robin@jarry.cc>
Acked-by: Tim Culverhouse <tim@timculverhouse.com>

1 files changed, 62 insertions, 28 deletions

diff --git a/config/binds.go b/config/binds.go
index 6ddeb1e1..abaff78c 100644
--- a/config/binds.go
+++ b/config/binds.go
@@ -27,11 +27,17 @@ type BindingConfig struct {
 	Terminal               *KeyBindings
 }
 
+type bindsContextType int
+
+const (
+	bindsContextFolder bindsContextType = iota
+	bindsContextAccount
+)
+
 type BindingConfigContext struct {
-	ContextType ContextType
+	ContextType bindsContextType
 	Regex       *regexp.Regexp
 	Bindings    *KeyBindings
-	BindContext string
 }
 
 type KeyStroke struct {
@@ -47,11 +53,20 @@ type Binding struct {
 
 type KeyBindings struct {
 	Bindings []*Binding
-
 	// If false, disable global keybindings in this context
 	Globals bool
 	// Which key opens the ex line (default is :)
 	ExKey KeyStroke
+
+	// private
+	contextualBinds  []*BindingConfigContext
+	contextualCounts map[bindsContextType]int
+	contextualCache  map[bindsContextKey]*KeyBindings
+}
+
+type bindsContextKey struct {
+	ctxType bindsContextType
+	value   string
 }
 
 const (
@@ -115,13 +130,6 @@ func (config *AercConfig) parseBinds(root string) error {
 		}
 	}
 
-	config.Bindings.Global.Globals = false
-	for _, contextBind := range config.ContextualBinds {
-		if contextBind.BindContext == "default" {
-			contextBind.Bindings.Globals = false
-		}
-	}
-
 	log.Debugf("binds.conf: %#v", config.Bindings)
 	return nil
 }
@@ -168,6 +176,12 @@ func (config *AercConfig) LoadBinds(binds *ini.File, baseName string, baseGroup
 		*baseGroup = MergeBindings(binds, *baseGroup)
 	}
 
+	b := *baseGroup
+
+	if baseName == "default" {
+		b.Globals = false
+	}
+
 	for _, sectionName := range binds.SectionStrings() {
 		if !strings.Contains(sectionName, baseName+":") ||
 			strings.Contains(sectionName, baseName+"::") {
@@ -183,10 +197,12 @@ func (config *AercConfig) LoadBinds(binds *ini.File, baseName string, baseGroup
 		if err != nil {
 			return err
 		}
+		if baseName == "default" {
+			binds.Globals = false
+		}
 
 		contextualBind := BindingConfigContext{
-			Bindings:    binds,
-			BindContext: baseName,
+			Bindings: binds,
 		}
 
 		var index int
@@ -215,15 +231,16 @@ func (config *AercConfig) LoadBinds(binds *ini.File, baseName string, baseGroup
 				log.Warnf("binds.conf: unexistent account: %s", acctName)
 				continue
 			}
-			contextualBind.ContextType = BIND_CONTEXT_ACCOUNT
+			contextualBind.ContextType = bindsContextAccount
 		case "folder":
 			// No validation needed. If the folder doesn't exist, the binds
 			// never get used
-			contextualBind.ContextType = BIND_CONTEXT_FOLDER
+			contextualBind.ContextType = bindsContextFolder
 		default:
 			return fmt.Errorf("Unknown Context Bind Section: %s", sectionName)
 		}
-		config.ContextualBinds = append(config.ContextualBinds, contextualBind)
+		b.contextualBinds = append(b.contextualBinds, &contextualBind)
+		b.contextualCounts[contextualBind.ContextType]++
 	}
 
 	return nil
@@ -245,8 +262,10 @@ func defaultBindsConfig() BindingConfig {
 
 func NewKeyBindings() *KeyBindings {
 	return &KeyBindings{
-		ExKey:   KeyStroke{tcell.ModNone, tcell.KeyRune, ':'},
-		Globals: true,
+		ExKey:            KeyStroke{tcell.ModNone, tcell.KeyRune, ':'},
+		Globals:          true,
+		contextualCache:  make(map[bindsContextKey]*KeyBindings),
+		contextualCounts: make(map[bindsContextType]int),
 	}
 }
 
@@ -260,26 +279,41 @@ func MergeBindings(bindings ...*KeyBindings) *KeyBindings {
 	return merged
 }
 
-func (config AercConfig) MergeContextualBinds(baseBinds *KeyBindings,
-	contextType ContextType, reg string, bindCtx string,
+func (base *KeyBindings) contextual(
+	contextType bindsContextType, reg string,
 ) *KeyBindings {
-	bindings := baseBinds
-	for _, contextualBind := range config.ContextualBinds {
+	if base.contextualCounts[contextType] == 0 {
+		// shortcut if no contextual binds for that type
+		return base
+	}
+
+	key := bindsContextKey{ctxType: contextType, value: reg}
+	c, found := base.contextualCache[key]
+	if found {
+		return c
+	}
+
+	c = base
+	for _, contextualBind := range base.contextualBinds {
 		if contextualBind.ContextType != contextType {
 			continue
 		}
-
 		if !contextualBind.Regex.Match([]byte(reg)) {
 			continue
 		}
+		c = MergeBindings(contextualBind.Bindings, c)
+	}
+	base.contextualCache[key] = c
 
-		if contextualBind.BindContext != bindCtx {
-			continue
-		}
+	return c
+}
 
-		bindings = MergeBindings(contextualBind.Bindings, bindings)
-	}
-	return bindings
+func (bindings *KeyBindings) ForAccount(account string) *KeyBindings {
+	return bindings.contextual(bindsContextAccount, account)
+}
+
+func (bindings *KeyBindings) ForFolder(folder string) *KeyBindings {
+	return bindings.contextual(bindsContextFolder, folder)
 }
 
 func (bindings *KeyBindings) Add(binding *Binding) {