binds: display active keybinds in a dialog box

Show contextual keybinds in a textbox when using the ':help keys'
command. This command is bound to '?' by default.

Fixes: https://todo.sr.ht/~rjarry/aerc/42
Signed-off-by: Koni Marti <koni.marti@gmail.com>
Acked-by: Robin Jarry <robin@jarry.cc>

2 files changed, 57 insertions, 0 deletions

diff --git a/widgets/aerc.go b/widgets/aerc.go
index 1e2a4cdd..f0bc1ba7 100644
--- a/widgets/aerc.go
+++ b/widgets/aerc.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"net/url"
+	"sort"
 	"strings"
 	"time"
 
@@ -199,6 +200,40 @@ func (aerc *Aerc) Draw(ctx *ui.Context) {
 	}
 }
 
+func (aerc *Aerc) HumanReadableBindings() []string {
+	var result []string
+	binds := aerc.getBindings()
+	format := func(s string) string {
+		s = strings.ReplaceAll(s, "<space>", " ")
+		return strings.ReplaceAll(s, "%", "%%")
+	}
+	fmtStr := "%10s %s"
+	for _, bind := range binds.Bindings {
+		result = append(result, fmt.Sprintf(fmtStr,
+			format(config.FormatKeyStrokes(bind.Input)),
+			format(config.FormatKeyStrokes(bind.Output)),
+		))
+	}
+	if binds.Globals && aerc.conf.Bindings.Global != nil {
+		for _, bind := range aerc.conf.Bindings.Global.Bindings {
+			result = append(result, fmt.Sprintf(fmtStr+" (Globals)",
+				format(config.FormatKeyStrokes(bind.Input)),
+				format(config.FormatKeyStrokes(bind.Output)),
+			))
+		}
+	}
+	result = append(result, fmt.Sprintf(fmtStr,
+		"$ex",
+		fmt.Sprintf("'%c'", binds.ExKey.Rune),
+	))
+	result = append(result, fmt.Sprintf(fmtStr,
+		"Globals",
+		fmt.Sprintf("%v", binds.Globals),
+	))
+	sort.Strings(result)
+	return result
+}
+
 func (aerc *Aerc) getBindings() *config.KeyBindings {
 	selectedAccountName := ""
 	if aerc.SelectedAccount() != nil {
diff --git a/widgets/msgviewer.go b/widgets/msgviewer.go
index 4d70e93d..70ff5d8f 100644
--- a/widgets/msgviewer.go
+++ b/widgets/msgviewer.go
@@ -392,6 +392,22 @@ func (mv *MessageViewer) Close() error {
 	return nil
 }
 
+func (mv *MessageViewer) UpdateScreen() {
+	if mv.switcher == nil {
+		return
+	}
+	parts := mv.switcher.parts
+	selected := mv.switcher.selected
+	if selected < 0 {
+		return
+	}
+	if len(parts) > 0 && selected < len(parts) {
+		if part := parts[selected]; part != nil {
+			part.UpdateScreen()
+		}
+	}
+}
+
 func (ps *PartSwitcher) Invalidate() {
 	ps.DoInvalidate(ps)
 }
@@ -628,6 +644,12 @@ func (pv *PartViewer) SetSource(reader io.Reader) {
 	pv.attemptCopy()
 }
 
+func (pv *PartViewer) UpdateScreen() {
+	if pv.term != nil {
+		pv.term.Invalidate()
+	}
+}
+
 func (pv *PartViewer) attemptCopy() {
 	if pv.source == nil || pv.pager == nil || pv.pager.Process == nil {
 		return