From 31bbaad06e3815082d5cfa3b3bc7817da5e6ecd1 Mon Sep 17 00:00:00 2001
From: Junegunn Choi <junegunn.c@gmail.com>
Date: Sun, 30 Oct 2022 20:44:46 +0900
Subject: [PATCH] Add --preview-label and --preview-label-pos

Close #3022
---
 CHANGELOG.md    |  2 ++
 src/options.go  | 15 +++++++++++++
 src/terminal.go | 57 +++++++++++++++++++++++++++++++------------------
 3 files changed, 53 insertions(+), 21 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e47a14fb..42f70e3e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -24,6 +24,8 @@ CHANGELOG
   # Right-aligned (negative integer)
   fzf --height=10 --border-label="╢ $label ╟" --border=bottom --border-label-pos=-3 --color=label:italic:black
   ```
+- Also added `--preview-label` and `--preview-label-pos` for the border of the
+  preview window
 - Info panel (counter) will be followed by a horizontal separator by default
     - The color of the separator can be customized via `--color=separator:...`
     - Separator can be disabled by adding `:nosep` to `--info`
diff --git a/src/options.go b/src/options.go
index 36fd2055..d536dae6 100644
--- a/src/options.go
+++ b/src/options.go
@@ -96,6 +96,8 @@ const usage = `usage: fzf [options]
                            [,border-BORDER_OPT]
                            [,+SCROLL[OFFSETS][/DENOM]][,~HEADER_LINES]
                            [,default][,<SIZE_THRESHOLD(ALTERNATIVE_LAYOUT)]
+    --preview-label=LABEL
+    --preview-label-pos=COL
 
   Scripting
     -q, --query=STR        Start the finder with the given query
@@ -275,6 +277,8 @@ type Options struct {
 	BorderShape tui.BorderShape
 	Label       string
 	LabelPos    int
+	PLabel      string
+	PLabelPos   int
 	Unicode     bool
 	Tabstop     int
 	ClearOnExit bool
@@ -343,6 +347,8 @@ func defaultOptions() *Options {
 		Tabstop:     8,
 		Label:       "",
 		LabelPos:    0,
+		PLabel:      "",
+		PLabelPos:   0,
 		ClearOnExit: true,
 		Version:     false}
 }
@@ -1593,6 +1599,11 @@ func parseOptions(opts *Options, allArgs []string) {
 		case "--border-label-pos":
 			pos := nextString(allArgs, &i, "label position required (positive or negative integer or 'center')")
 			opts.LabelPos = parseLabelPosition(pos)
+		case "--preview-label":
+			opts.PLabel = nextString(allArgs, &i, "preview label required")
+		case "--preview-label-pos":
+			pos := nextString(allArgs, &i, "preview label position required (positive or negative integer or 'center')")
+			opts.PLabelPos = parseLabelPosition(pos)
 		case "--no-unicode":
 			opts.Unicode = false
 		case "--unicode":
@@ -1632,6 +1643,10 @@ func parseOptions(opts *Options, allArgs []string) {
 				opts.Label = value
 			} else if match, value := optString(arg, "--border-label-pos="); match {
 				opts.LabelPos = parseLabelPosition(value)
+			} else if match, value := optString(arg, "--preview-label="); match {
+				opts.PLabel = value
+			} else if match, value := optString(arg, "--preview-label-pos="); match {
+				opts.PLabelPos = parseLabelPosition(value)
 			} else if match, value := optString(arg, "--prompt="); match {
 				opts.Prompt = value
 			} else if match, value := optString(arg, "--pointer="); match {
diff --git a/src/terminal.go b/src/terminal.go
index ca50de42..2764ff85 100644
--- a/src/terminal.go
+++ b/src/terminal.go
@@ -117,6 +117,9 @@ type Terminal struct {
 	borderLabel        func()
 	borderLabelLen     int
 	borderLabelPos     int
+	previewLabel       func()
+	previewLabelLen    int
+	previewLabelPos    int
 	pointer            string
 	pointerLen         int
 	pointerEmpty       string
@@ -549,6 +552,8 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 		borderShape:        opts.BorderShape,
 		borderLabel:        nil,
 		borderLabelPos:     opts.LabelPos,
+		previewLabel:       nil,
+		previewLabelPos:    opts.PLabelPos,
 		cleanExit:          opts.ClearOnExit,
 		paused:             opts.Phony,
 		strong:             strongAttr,
@@ -595,6 +600,9 @@ func NewTerminal(opts *Options, eventBox *util.EventBox) *Terminal {
 	if len(opts.Label) > 0 {
 		t.borderLabel, t.borderLabelLen = t.parseBorderLabel(opts.Label)
 	}
+	if len(opts.PLabel) > 0 {
+		t.previewLabel, t.previewLabelLen = t.parseBorderLabel(opts.PLabel)
+	}
 
 	return &t
 }
@@ -938,27 +946,6 @@ func (t *Terminal) resizeWindows() {
 			false, tui.MakeBorderStyle(t.borderShape, t.unicode))
 	}
 
-	// Print border label
-	if t.border != nil && t.borderLabel != nil {
-		switch t.borderShape {
-		case tui.BorderHorizontal, tui.BorderTop, tui.BorderBottom, tui.BorderRounded, tui.BorderSharp:
-			var col int
-			if t.borderLabelPos == 0 {
-				col = util.Max(0, (t.border.Width()-t.borderLabelLen)/2)
-			} else if t.borderLabelPos < 0 {
-				col = util.Max(0, t.border.Width()+t.borderLabelPos+1-t.borderLabelLen)
-			} else {
-				col = util.Min(t.borderLabelPos-1, t.border.Width()-t.borderLabelLen)
-			}
-			row := 0
-			if t.borderShape == tui.BorderBottom {
-				row = t.border.Height() - 1
-			}
-			t.border.Move(row, col)
-			t.borderLabel()
-		}
-	}
-
 	// Add padding to margin
 	for idx, val := range paddingInt {
 		marginInt[idx] += val
@@ -1063,6 +1050,34 @@ func (t *Terminal) resizeWindows() {
 			width,
 			height, false, noBorder)
 	}
+
+	// Print border label
+	printLabel := func(window tui.Window, render func(), pos int, length int, borderShape tui.BorderShape) {
+		if window == nil || render == nil {
+			return
+		}
+
+		switch borderShape {
+		case tui.BorderHorizontal, tui.BorderTop, tui.BorderBottom, tui.BorderRounded, tui.BorderSharp:
+			var col int
+			if pos == 0 {
+				col = util.Max(0, (window.Width()-length)/2)
+			} else if pos < 0 {
+				col = util.Max(0, window.Width()+pos+1-length)
+			} else {
+				col = util.Min(pos-1, window.Width()-length)
+			}
+			row := 0
+			if borderShape == tui.BorderBottom {
+				row = window.Height() - 1
+			}
+			window.Move(row, col)
+			render()
+		}
+	}
+	printLabel(t.border, t.borderLabel, t.borderLabelPos, t.borderLabelLen, t.borderShape)
+	printLabel(t.pborder, t.previewLabel, t.previewLabelPos, t.previewLabelLen, t.previewOpts.border)
+
 	for i := 0; i < t.window.Height(); i++ {
 		t.window.MoveAndClear(i, 0)
 	}