From f186ddf99917d42d20be6193fd35f14d5dfa554e Mon Sep 17 00:00:00 2001
From: Qi Xiao <xiaqqaix@gmail.com>
Date: Mon, 30 Dec 2024 17:37:25 +0000
Subject: [PATCH] Add flex weight to BoxView

---
 pkg/etk/comps/hiernav.go        |  2 +-
 pkg/etk/view.go                 | 80 +++++++++++++++++++--------------
 pkg/etkedit/addon_completion.go |  2 +-
 pkg/etkedit/addon_histlist.go   |  2 +-
 pkg/etkedit/addon_histwalk.go   |  2 +-
 pkg/etkedit/addon_lastcmd.go    |  2 +-
 pkg/etkedit/addon_location.go   |  2 +-
 pkg/etkedit/addon_minibuf.go    |  2 +-
 pkg/etkedit/addon_navigation.go |  2 +-
 pkg/etkedit/app.go              |  6 +--
 10 files changed, 57 insertions(+), 45 deletions(-)

diff --git a/pkg/etk/comps/hiernav.go b/pkg/etk/comps/hiernav.go
index 28a1cf89c..de4783cc5 100644
--- a/pkg/etk/comps/hiernav.go
+++ b/pkg/etk/comps/hiernav.go
@@ -45,7 +45,7 @@ func HierNav(c etk.Context) (etk.View, etk.React) {
 		}
 	}
 
-	return etk.Box("parent* 1 [current*] 1 preview*", parent, currentView, preview),
+	return etk.Box("parent*1 1 [current*3] 1 preview*4", parent, currentView, preview),
 		func(e term.Event) etk.Reaction {
 			switch e {
 			case term.K(ui.Left):
diff --git a/pkg/etk/view.go b/pkg/etk/view.go
index f0311246b..69215f559 100644
--- a/pkg/etk/view.go
+++ b/pkg/etk/view.go
@@ -140,32 +140,34 @@ type BoxView struct {
 
 type BoxChild struct {
 	View View
-	Flex bool
+	Flex int // 0 for non-flex child, > 0 for flex weight
 }
 
 // Child verbs
 //  - "=" for non-flex child
-//  - "*" for flex child
+//  - "*" for flex child, may be followed by weight (default is 1)
 //
 // Example:
 //
-// a* b= c*
-
-// Expressing focus
+// a* b= c*2
+//
+// Names don't matter
+//
+// Expressing focus:
+//
+// a* [b=] c*2
+//
+// Expressing gap:
+//
+// a* 2 [b=] 1 c*2
 //
-// a* [b=] c*
-
-// Expressing gap
-
-// a* 2 [b=] 1 c*
-
 // Calling box
 //
-// Box("a* [b=] c*", aView, bView, cView)
+// Box("a* [b=] c*2", aView, bView, cView)
 //
 // Box(`a*
 //      [b=]
-//      c*`, aView, bView, cView)
+//      c*2`, aView, bView, cView)
 
 func Box(layout string, views ...View) BoxView {
 	return BoxFocus(layout, 0, views...)
@@ -199,9 +201,17 @@ func BoxFocus(layout string, focus int, views ...View) BoxView {
 			verb = verb[1 : len(verb)-1]
 			focus = len(children)
 		}
-		var flex bool
-		if strings.HasSuffix(verb, "*") {
-			flex = true
+		var flexWeight int
+		if _, weight, ok := strings.Cut(verb, "*"); ok {
+			if weight == "" {
+				flexWeight = 1
+			} else {
+				var err error
+				flexWeight, err = strconv.Atoi(weight)
+				if err != nil {
+					panic(fmt.Sprintf("bad weight: %s", weight))
+				}
+			}
 		} else if strings.HasSuffix(verb, "=") {
 		} else if n, err := strconv.Atoi(verb); err == nil {
 			var view View
@@ -210,12 +220,12 @@ func BoxFocus(layout string, focus int, views ...View) BoxView {
 			} else {
 				view = VerticalGapView{n}
 			}
-			children = append(children, BoxChild{view, false})
+			children = append(children, BoxChild{view, 0})
 			continue
 		} else {
 			panic(fmt.Sprintf("invalid verb (must be number or end in * or =): %q", verb))
 		}
-		children = append(children, BoxChild{views[j], flex})
+		children = append(children, BoxChild{views[j], flexWeight})
 		j++
 	}
 	if j != len(views) {
@@ -225,19 +235,20 @@ func BoxFocus(layout string, focus int, views ...View) BoxView {
 }
 
 func (v BoxView) Render(width, height int) *term.Buffer {
-	var render func(View, bool) *term.Buffer
-	var flexChildren int
+	var render func(View, int) *term.Buffer
+	var flexWeightSum int
 	if v.Horizontal {
 		budget := width
-		render = func(v View, flex bool) *term.Buffer {
+		render = func(v View, flexWeight int) *term.Buffer {
 			width := budget
-			if flex {
-				width = budget / flexChildren
+			if flexWeight > 0 {
+				width = budget * flexWeight / flexWeightSum
+				flexWeightSum -= flexWeight
 			}
 			buf := v.Render(width, height)
 			// TODO: Maybe term.Buffer should keep track of the actual width
 			// itself
-			if !flex {
+			if flexWeight == 0 {
 				actualWidth := 0
 				for _, line := range buf.Lines {
 					actualWidth = max(actualWidth, cellsWidth(line))
@@ -249,10 +260,11 @@ func (v BoxView) Render(width, height int) *term.Buffer {
 		}
 	} else {
 		budget := height
-		render = func(v View, flex bool) *term.Buffer {
+		render = func(v View, flexWeight int) *term.Buffer {
 			height := budget
-			if flex {
-				height = budget / flexChildren
+			if flexWeight > 0 {
+				height = budget * flexWeight / flexWeightSum
+				flexWeightSum -= flexWeight
 			}
 			buf := v.Render(width, height)
 			budget -= len(buf.Lines)
@@ -263,17 +275,17 @@ func (v BoxView) Render(width, height int) *term.Buffer {
 	childBufs := make([]*term.Buffer, len(v.Children))
 	// Render non-flex children first.
 	for i, child := range v.Children {
-		if child.Flex {
-			flexChildren++
+		if child.Flex > 0 {
+			flexWeightSum += child.Flex
 		} else {
-			childBufs[i] = render(child.View, false)
+			childBufs[i] = render(child.View, 0)
 		}
 	}
-	// Render flex children first.
+	// Render flex children now.
 	for i, child := range v.Children {
-		if child.Flex {
-			childBufs[i] = render(child.View, true)
-			flexChildren--
+		if child.Flex > 0 {
+			childBufs[i] = render(child.View, child.Flex)
+			flexWeightSum--
 		}
 	}
 
diff --git a/pkg/etkedit/addon_completion.go b/pkg/etkedit/addon_completion.go
index b7f8ba427..c0c01507b 100644
--- a/pkg/etkedit/addon_completion.go
+++ b/pkg/etkedit/addon_completion.go
@@ -69,7 +69,7 @@ func startCompletion(ed *Editor, c etk.Context) {
 			}
 			return r
 		}),
-		true,
+		1,
 		func() { pendingVar.Set(comps.PendingText{}) },
 	)
 }
diff --git a/pkg/etkedit/addon_histlist.go b/pkg/etkedit/addon_histlist.go
index 0dffb2918..ec64594a7 100644
--- a/pkg/etkedit/addon_histlist.go
+++ b/pkg/etkedit/addon_histlist.go
@@ -35,7 +35,7 @@ func startHistlist(ed *Editor, c etk.Context) {
 			// TODO: Implement insertion of selected item
 			return r
 		},
-	), true)
+	), 1)
 }
 
 type histlistItems struct {
diff --git a/pkg/etkedit/addon_histwalk.go b/pkg/etkedit/addon_histwalk.go
index c1812514d..2e135008f 100644
--- a/pkg/etkedit/addon_histwalk.go
+++ b/pkg/etkedit/addon_histwalk.go
@@ -30,7 +30,7 @@ func startHistwalk(ed *Editor, c etk.Context) {
 			// TODO: Handle up/down
 			return r
 		}),
-		true,
+		1,
 		func() { pendingVar.Set(comps.PendingText{}) },
 	)
 }
diff --git a/pkg/etkedit/addon_lastcmd.go b/pkg/etkedit/addon_lastcmd.go
index 49f3d14e8..9cf4fa1e0 100644
--- a/pkg/etkedit/addon_lastcmd.go
+++ b/pkg/etkedit/addon_lastcmd.go
@@ -26,7 +26,7 @@ func startLastcmd(ed *Editor, c etk.Context) {
 			return items, 0
 		},
 		"binding", etkBindingFromBindingMap(ed, &ed.lastcmdBinding),
-	), true)
+	), 1)
 }
 
 type lastcmdItems struct {
diff --git a/pkg/etkedit/addon_location.go b/pkg/etkedit/addon_location.go
index 0c1757e14..1792e12f9 100644
--- a/pkg/etkedit/addon_location.go
+++ b/pkg/etkedit/addon_location.go
@@ -23,7 +23,7 @@ func startLocation(ed *Editor, c etk.Context) {
 			return locationItems{dirs}, 0
 		},
 		"binding", etkBindingFromBindingMap(ed, &ed.locationBinding),
-	), true)
+	), 1)
 }
 
 type locationItems struct {
diff --git a/pkg/etkedit/addon_minibuf.go b/pkg/etkedit/addon_minibuf.go
index 33219a892..1d3bd27a8 100644
--- a/pkg/etkedit/addon_minibuf.go
+++ b/pkg/etkedit/addon_minibuf.go
@@ -24,7 +24,7 @@ func startMinibuf(c etk.Context) {
 				c.AddMsg(modes.ErrorText(err))
 			}
 		},
-	), true)
+	), 1)
 }
 
 // TODO: Is this the correct abstraction??
diff --git a/pkg/etkedit/addon_navigation.go b/pkg/etkedit/addon_navigation.go
index 49959a2ca..3513b96f3 100644
--- a/pkg/etkedit/addon_navigation.go
+++ b/pkg/etkedit/addon_navigation.go
@@ -5,7 +5,7 @@ import "src.elv.sh/pkg/etk"
 func startNavigation(ed *Editor, c etk.Context) {
 	pushAddon(c, etk.WithInit(
 		navigation,
-		"binding", etkBindingFromBindingMap(ed, &ed.navigationBinding)), true)
+		"binding", etkBindingFromBindingMap(ed, &ed.navigationBinding)), 1)
 }
 
 func navigation(c etk.Context) (etk.View, etk.React) {
diff --git a/pkg/etkedit/app.go b/pkg/etkedit/app.go
index 4ae65e782..f67682b95 100644
--- a/pkg/etkedit/app.go
+++ b/pkg/etkedit/app.go
@@ -18,7 +18,7 @@ type addons struct {
 
 type addon struct {
 	Comp    etk.Comp
-	Flex    bool
+	Flex    int
 	Dismiss func()
 	ID      int
 }
@@ -77,11 +77,11 @@ func app(c etk.Context) (etk.View, etk.React) {
 		}
 }
 
-func pushAddon(c etk.Context, f etk.Comp, flex bool) {
+func pushAddon(c etk.Context, f etk.Comp, flex int) {
 	pushAddonWithDismiss(c, f, flex, nil)
 }
 
-func pushAddonWithDismiss(c etk.Context, f etk.Comp, flex bool, dismiss func()) {
+func pushAddonWithDismiss(c etk.Context, f etk.Comp, flex int, dismiss func()) {
 	addonsVar := etk.BindState(c, "addons", addons{})
 	addonsVar.Swap(func(a addons) addons {
 		// TODO: Is the use of append correct here??