[#1223] lens/tui: Add help page

Signed-off-by: Aleksey Savchuk <a.savchuk@yadro.com>

cmd/frostfs-lens/internal/meta/tui.go

@@ -41,10 +41,10 @@ func runTUI(cmd *cobra.Command) error {
 	app := tview.NewApplication()
 	ui := tuiutil.NewUI(ctx, app, db)
 
-	_ = ui.AddFilter("cid", cidParser)
-	_ = ui.AddFilter("oid", oidParser)
-	_ = ui.AddCompositeFilter("addr", addrParser)
-	_ = ui.AddCompositeFilter("attr", attributeParser)
+	_ = ui.AddFilter("cid", cidParser, "<CID>")
+	_ = ui.AddFilter("oid", oidParser, "<OID>")
+	_ = ui.AddCompositeFilter("addr", addrParser, "<CID>/<OID>")
+	_ = ui.AddCompositeFilter("attr", attributeParser, "<key> or <key>/<value>")
 
 	app.SetRoot(ui, true).SetFocus(ui)
 

cmd/frostfs-lens/internal/tuiutil/help.go

@@ -1 +1,83 @@
 package tuiutil
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/gdamore/tcell/v2"
+	"github.com/rivo/tview"
+)
+
+const text = `[green]Navigation[white]
+
+- [yellow]Up arrow[white]                Move up.
+
+- [yellow]Down arrow[white]              Move down.
+
+- [yellow]Space[white]                   Show a bucket's subbuckets if on the buckets view.
+
+- [yellow]Enter[white]                   Show a bucket's records if on the buckets view,
+						  or show a record's detailed view if on the
+						  records view. It always navigates to a new page.
+
+- [yellow]Escape[white]                  Go to the previous page.
+
+
+[green]Searching[white]
+
+- [yellow]/[white]                       Start search prompt.
+						  Prompt syntax is <filter tag>:<filter args...>.
+						  It tolerates leading and trailing white space.
+
+- [yellow]Enter[white]                   Start searching based on prompt. It shows an
+						  error message if the prompt is invalid.
+
+- [yellow]Escape[white]                  Stop search prompt.
+
+
+[green]Available search filters[white]
+
+%s
+`
+
+type HelpPage struct {
+	*tview.Box
+	view *tview.TextView
+}
+
+func NewHelpPage(filters []string, hints map[string]string) *HelpPage {
+	hp := &HelpPage{
+		Box:  tview.NewBox(),
+		view: tview.NewTextView(),
+	}
+
+	filtersText := strings.Builder{}
+
+	lastIndex := len(filters) - 1
+	for index, filter := range filters {
+		filtersText.WriteString("- ")
+		filtersText.WriteString(filter)
+		filtersText.WriteRune(' ')
+		filtersText.WriteString(hints[filter])
+		if index != lastIndex {
+			filtersText.WriteRune('\n')
+		}
+	}
+
+	hp.view.SetDynamicColors(true)
+	hp.view.SetText(fmt.Sprintf(text, filtersText.String()))
+
+	return hp
+}
+
+func (hp *HelpPage) Draw(screen tcell.Screen) {
+	x, y, width, height := hp.GetInnerRect()
+	hp.view.SetRect(x, y, width, height)
+	hp.view.Draw(screen)
+}
+
+func (hp *HelpPage) InputHandler() func(event *tcell.EventKey, setFocus func(p tview.Primitive)) {
+	return hp.WrapInputHandler(func(event *tcell.EventKey, _ func(tview.Primitive)) {
+		hp.view.InputHandler()(event, func(tview.Primitive) {})
+	})
+}

cmd/frostfs-lens/internal/tuiutil/ui.go

@@ -47,8 +47,9 @@ type UI struct {
 	infoBar    *tview.TextView
 	searchBar  *tview.InputField
 	loadingBar *LoadingBar
+	helpBar    *tview.TextView
 
-	helpPage *tview.TextView
+	helpPage *HelpPage
 
 	searchErrorBar *tview.TextView
 
@@ -64,6 +65,7 @@ type UI struct {
 
 	filters          map[string]func(string) (any, error)
 	compositeFilters map[string]func(string) (map[string]any, error)
+	filterHints      map[string]string
 }
 
 func NewUI(ctx context.Context, app *tview.Application, db *bbolt.DB) *UI {
@@ -77,8 +79,9 @@ func NewUI(ctx context.Context, app *tview.Application, db *bbolt.DB) *UI {
 		isFirstMount:     true,
 		infoBar:          tview.NewTextView(),
 		pageStub:         tview.NewBox(),
-		helpPage:         tview.NewTextView(),
 		searchBar:        tview.NewInputField(),
+		filterHints:      make(map[string]string),
+		helpBar:          tview.NewTextView(),
 		searchErrorBar:   tview.NewTextView(),
 		filters:          make(map[string]func(string) (any, error)),
 		compositeFilters: make(map[string]func(string) (map[string]any, error)),
@@ -97,14 +100,16 @@ func NewUI(ctx context.Context, app *tview.Application, db *bbolt.DB) *UI {
 	ui.infoBar.SetBackgroundColor(barBackgroundColor)
 	ui.infoBar.SetTextColor(barTextColor)
 
+	ui.helpBar.SetBackgroundColor(barBackgroundColor)
+	ui.helpBar.SetTextColor(barTextColor)
+	ui.helpBar.SetText(" Press Escape to quit")
+
 	ui.searchErrorBar.SetBackgroundColor(barTextColor)
 	ui.searchErrorBar.SetTextColor(barAlertTextColor)
 
 	ui.loadingBar = NewLoadingBar(ui.triggerDraw)
 	ui.pageToMount = NewBucketsView(ui, NewFilter(nil))
 
-	ui.helpPage.SetText("Work In Progress【ツ】")
-
 	ui.searchBar.SetLabel("/")
 	ui.infoBar.SetText(fmt.Sprintf(" %s (press h for help, / to search or q to quit) ", db.Path()))
 
@@ -124,22 +129,26 @@ func (ui *UI) checkFilterExists(typ string) bool {
 func (ui *UI) AddFilter(
 	typ string,
 	parser func(string) (any, error),
+	helpHint string,
 ) error {
 	if ui.checkFilterExists(typ) {
 		return fmt.Errorf("filter %s already exists", typ)
 	}
 	ui.filters[typ] = parser
+	ui.filterHints[typ] = helpHint
 	return nil
 }
 
 func (ui *UI) AddCompositeFilter(
 	typ string,
 	parser func(string) (map[string]any, error),
+	helpHint string,
 ) error {
 	if ui.checkFilterExists(typ) {
 		return fmt.Errorf("filter %s already exists", typ)
 	}
 	ui.compositeFilters[typ] = parser
+	ui.filterHints[typ] = helpHint
 	return nil
 }
 
@@ -222,26 +231,27 @@ func (ui *UI) draw(screen tcell.Screen) {
 	var (
 		pageToDraw tview.Primitive
 		barToDraw  tview.Primitive
-
-		needDrawBar = true
 	)
 
 	switch {
 	case ui.isShowingHelp:
+		if ui.helpPage == nil {
+			var filters []string
+			for f := range ui.filters {
+				filters = append(filters, f)
+			}
+			for f := range ui.compositeFilters {
+				filters = append(filters, f)
+			}
+			ui.helpPage = NewHelpPage(filters, ui.filterHints)
+		}
 		pageToDraw = ui.helpPage
-		needDrawBar = false
 	case ui.mountedPage != nil:
 		pageToDraw = ui.mountedPage
 	default:
 		pageToDraw = ui.pageStub
 	}
 
-	if !needDrawBar {
-		pageToDraw.SetRect(x, y, width, height)
-		pageToDraw.Draw(screen)
-		return
-	}
-
 	pageToDraw.SetRect(x, y, width, height-1)
 	pageToDraw.Draw(screen)
 
@@ -252,6 +262,8 @@ func (ui *UI) draw(screen tcell.Screen) {
 		barToDraw = ui.searchBar
 	case ui.isShowingError:
 		barToDraw = ui.searchErrorBar
+	case ui.isShowingHelp:
+		barToDraw = ui.helpBar
 	default:
 		barToDraw = ui.infoBar
 	}
@@ -447,7 +459,7 @@ func (ui *UI) processPrompt(prompt string) (filter *Filter, err error) {
 
 	parts := strings.Split(prompt, ":")
 	if len(parts) != 2 {
-		return nil, errors.New("invalid syntax, expected <filter id>:<filter value>")
+		return nil, errors.New("invalid syntax, expected <filter id>:<filter args...>")
 	}
 
 	filterID := strings.TrimSpace(parts[0])