Color customization (#245)

5 files changed, 257 insertions, 90 deletions

diff --git a/man/man1/fzf.1 b/man/man1/fzf.1
index 1a9720be..9f652e0c 100644
--- a/man/man1/fzf.1
+++ b/man/man1/fzf.1
@@ -91,21 +91,38 @@ Enable processing of ANSI color codes
 .B "--no-mouse"
 Disable mouse
 .TP
-.B "--color=COL"
-Color scheme: [dark|light|16|bw]
-.br
-(default: dark on 256-color terminal, otherwise 16)
-.br
-.R ""
-.br
-.BR dark "    Color scheme for dark 256-color terminal"
-.br
-.BR light "   Color scheme for light 256-color terminal"
-.br
-.BR 16 "      Color scheme for 16-color terminal"
-.br
-.BR bw "      No colors"
-.br
+.BI "--color=" "[BASE_SCHEME][,COLOR:ANSI]"
+Color configuration. The name of the base color scheme is followed by custom
+color mappings. Ansi color code of -1 denotes terminal default
+foreground/background color.
+
+.RS
+e.g. \fBfzf --color=bg+:24\fR
+     \fBfzf --color=light,fg:232,bg:255,bg+:116,info:27\fR
+.RE
+
+.RS
+.B BASE SCHEME:
+    (default: dark on 256-color terminal, otherwise 16)
+
+    \fBdark    \fRColor scheme for dark 256-color terminal
+    \fBlight   \fRColor scheme for light 256-color terminal
+    \fB16      \fRColor scheme for 16-color terminal
+    \fBbw      \fRNo colors
+
+.B COLOR:
+    \fBfg      \fRText
+    \fBbg      \fRBackground
+    \fBhl      \fRHighlighted substrings
+    \fBfg+     \fRText (current line)
+    \fBbg+     \fRBackground (current line)
+    \fBhl+     \fRHighlighted substrings (current line)
+    \fBinfo    \fRInfo
+    \fBprompt  \fRPrompt
+    \fBpointer \fRPointer to the current line
+    \fBmarker  \fRMulti-select marker
+    \fBspinner \fRStreaming input indicator
+.RE
 .TP
 .B "--black"
 Use black background
diff --git a/src/curses/curses.go b/src/curses/curses.go
index 44fab4fb..985dd87f 100644
--- a/src/curses/curses.go
+++ b/src/curses/curses.go
@@ -106,15 +106,18 @@ const (
 )
 
 type ColorTheme struct {
-	darkBg       C.short
-	prompt       C.short
-	match        C.short
-	current      C.short
-	currentMatch C.short
-	spinner      C.short
-	info         C.short
-	cursor       C.short
-	selected     C.short
+	UseDefault   bool
+	Fg           int16
+	Bg           int16
+	DarkBg       int16
+	Prompt       int16
+	Match        int16
+	Current      int16
+	CurrentMatch int16
+	Spinner      int16
+	Info         int16
+	Cursor       int16
+	Selected     int16
 }
 
 type Event struct {
@@ -142,7 +145,10 @@ var (
 	Default16     *ColorTheme
 	Dark256       *ColorTheme
 	Light256      *ColorTheme
-	DarkBG        C.short
+	FG            int
+	CurrentFG     int
+	BG            int
+	DarkBG        int
 )
 
 func init() {
@@ -150,35 +156,44 @@ func init() {
 	_clickY = []int{}
 	_colorMap = make(map[int]int)
 	Default16 = &ColorTheme{
-		darkBg:       C.COLOR_BLACK,
-		prompt:       C.COLOR_BLUE,
-		match:        C.COLOR_GREEN,
-		current:      C.COLOR_YELLOW,
-		currentMatch: C.COLOR_GREEN,
-		spinner:      C.COLOR_GREEN,
-		info:         C.COLOR_WHITE,
-		cursor:       C.COLOR_RED,
-		selected:     C.COLOR_MAGENTA}
+		UseDefault:   true,
+		Fg:           15,
+		Bg:           0,
+		DarkBg:       C.COLOR_BLACK,
+		Prompt:       C.COLOR_BLUE,
+		Match:        C.COLOR_GREEN,
+		Current:      C.COLOR_YELLOW,
+		CurrentMatch: C.COLOR_GREEN,
+		Spinner:      C.COLOR_GREEN,
+		Info:         C.COLOR_WHITE,
+		Cursor:       C.COLOR_RED,
+		Selected:     C.COLOR_MAGENTA}
 	Dark256 = &ColorTheme{
-		darkBg:       236,
-		prompt:       110,
-		match:        108,
-		current:      254,
-		currentMatch: 151,
-		spinner:      148,
-		info:         144,
-		cursor:       161,
-		selected:     168}
+		UseDefault:   true,
+		Fg:           15,
+		Bg:           0,
+		DarkBg:       236,
+		Prompt:       110,
+		Match:        108,
+		Current:      254,
+		CurrentMatch: 151,
+		Spinner:      148,
+		Info:         144,
+		Cursor:       161,
+		Selected:     168}
 	Light256 = &ColorTheme{
-		darkBg:       251,
-		prompt:       25,
-		match:        66,
-		current:      237,
-		currentMatch: 23,
-		spinner:      65,
-		info:         101,
-		cursor:       161,
-		selected:     168}
+		UseDefault:   true,
+		Fg:           15,
+		Bg:           0,
+		DarkBg:       251,
+		Prompt:       25,
+		Match:        66,
+		Current:      237,
+		CurrentMatch: 23,
+		Spinner:      65,
+		Info:         101,
+		Cursor:       161,
+		Selected:     168}
 }
 
 func attrColored(pair int, bold bool) C.int {
@@ -268,23 +283,35 @@ func Init(theme *ColorTheme, black bool, mouse bool) {
 }
 
 func initPairs(theme *ColorTheme, black bool) {
-	var bg C.short
+	fg := C.short(theme.Fg)
+	bg := C.short(theme.Bg)
 	if black {
 		bg = C.COLOR_BLACK
-	} else {
-		C.use_default_colors()
+	} else if theme.UseDefault {
+		fg = -1
 		bg = -1
+		C.use_default_colors()
+	}
+	if theme.UseDefault {
+		FG = -1
+		BG = -1
+	} else {
+		FG = int(fg)
+		BG = int(bg)
+		C.assume_default_colors(C.int(theme.Fg), C.int(bg))
 	}
 
-	DarkBG = theme.darkBg
-	C.init_pair(ColPrompt, theme.prompt, bg)
-	C.init_pair(ColMatch, theme.match, bg)
-	C.init_pair(ColCurrent, theme.current, DarkBG)
-	C.init_pair(ColCurrentMatch, theme.currentMatch, DarkBG)
-	C.init_pair(ColSpinner, theme.spinner, bg)
-	C.init_pair(ColInfo, theme.info, bg)
-	C.init_pair(ColCursor, theme.cursor, DarkBG)
-	C.init_pair(ColSelected, theme.selected, DarkBG)
+	CurrentFG = int(theme.Current)
+	DarkBG = int(theme.DarkBg)
+	darkBG := C.short(DarkBG)
+	C.init_pair(ColPrompt, C.short(theme.Prompt), bg)
+	C.init_pair(ColMatch, C.short(theme.Match), bg)
+	C.init_pair(ColCurrent, C.short(theme.Current), darkBG)
+	C.init_pair(ColCurrentMatch, C.short(theme.CurrentMatch), darkBG)
+	C.init_pair(ColSpinner, C.short(theme.Spinner), bg)
+	C.init_pair(ColInfo, C.short(theme.Info), bg)
+	C.init_pair(ColCursor, C.short(theme.Cursor), darkBG)
+	C.init_pair(ColSelected, C.short(theme.Selected), darkBG)
 }
 
 func Close() {
diff --git a/src/item.go b/src/item.go
index 711adbe2..7c2f94d5 100644
--- a/src/item.go
+++ b/src/item.go
@@ -143,13 +143,25 @@ func (item *Item) colorOffsets(color int, bold bool, current bool) []colorOffset
 					offset: Offset{int32(start), int32(idx)}, color: color, bold: bold})
 			} else {
 				ansi := item.colors[curr-1]
+				fg := ansi.color.fg
+				if fg == -1 {
+					if current {
+						fg = curses.CurrentFG
+					} else {
+						fg = curses.FG
+					}
+				}
 				bg := ansi.color.bg
-				if current && bg == -1 {
-					bg = int(curses.DarkBG)
+				if bg == -1 {
+					if current {
+						bg = curses.DarkBG
+					} else {
+						bg = curses.BG
+					}
 				}
 				offsets = append(offsets, colorOffset{
 					offset: Offset{int32(start), int32(idx)},
-					color:  curses.PairFor(ansi.color.fg, bg),
+					color:  curses.PairFor(fg, bg),
 					bold:   ansi.color.bold || bold})
 			}
 		}
diff --git a/src/options.go b/src/options.go
index 15317495..63037eaa 100644
--- a/src/options.go
+++ b/src/options.go
@@ -4,6 +4,7 @@ import (
 	"fmt"
 	"os"
 	"regexp"
+	"strconv"
 	"strings"
 	"unicode/utf8"
 
@@ -35,8 +36,7 @@ const usage = `usage: fzf [options]
     -m, --multi           Enable multi-select with tab/shift-tab
         --ansi            Enable processing of ANSI color codes
         --no-mouse        Disable mouse
-        --color=COL       Color scheme; [dark|light|16|bw]
-                          (default: dark on 256-color terminal, otherwise 16)
+        --color=COLSPEC   Base scheme (dark|light|16|bw) and/or custom colors
         --black           Use black background
         --reverse         Reverse orientation
         --no-hscroll      Disable horizontal scroll
@@ -121,14 +121,14 @@ type Options struct {
 	Version    bool
 }
 
-func defaultOptions() *Options {
-	var defaultTheme *curses.ColorTheme
+func defaultTheme() *curses.ColorTheme {
 	if strings.Contains(os.Getenv("TERM"), "256") {
-		defaultTheme = curses.Dark256
-	} else {
-		defaultTheme = curses.Default16
+		return curses.Dark256
 	}
+	return curses.Default16
+}
 
+func defaultOptions() *Options {
 	return &Options{
 		Mode:       ModeFuzzy,
 		Case:       CaseSmart,
@@ -141,7 +141,7 @@ func defaultOptions() *Options {
 		Multi:      false,
 		Ansi:       false,
 		Mouse:      true,
-		Theme:      defaultTheme,
+		Theme:      defaultTheme(),
 		Black:      false,
 		Reverse:    false,
 		Hscroll:    true,
@@ -187,6 +187,14 @@ func nextString(args []string, i *int, message string) string {
 	return args[*i]
 }
 
+func optionalNextString(args []string, i *int) string {
+	if len(args) > *i+1 {
+		*i++
+		return args[*i]
+	}
+	return ""
+}
+
 func optionalNumeric(args []string, i *int) int {
 	if len(args) > *i+1 {
 		if strings.IndexAny(args[*i+1], "0123456789") == 0 {
@@ -277,20 +285,72 @@ func parseTiebreak(str string) tiebreak {
 	return byLength
 }
 
-func parseTheme(str string) *curses.ColorTheme {
-	switch strings.ToLower(str) {
-	case "dark":
-		return curses.Dark256
-	case "light":
-		return curses.Light256
-	case "16":
-		return curses.Default16
-	case "bw", "no":
-		return nil
-	default:
-		errorExit("invalid color scheme: " + str)
+func dupeTheme(theme *curses.ColorTheme) *curses.ColorTheme {
+	dupe := *theme
+	return &dupe
+}
+
+func parseTheme(defaultTheme *curses.ColorTheme, str string) *curses.ColorTheme {
+	theme := dupeTheme(defaultTheme)
+	for _, str := range strings.Split(strings.ToLower(str), ",") {
+		switch str {
+		case "dark":
+			theme = dupeTheme(curses.Dark256)
+		case "light":
+			theme = dupeTheme(curses.Light256)
+		case "16":
+			theme = dupeTheme(curses.Default16)
+		case "bw", "no":
+			theme = nil
+		default:
+			fail := func() {
+				errorExit("invalid color specification: " + str)
+			}
+			// Color is disabled
+			if theme == nil {
+				errorExit("colors disabled; cannot customize colors")
+			}
+
+			pair := strings.Split(str, ":")
+			if len(pair) != 2 {
+				fail()
+			}
+			ansi32, err := strconv.Atoi(pair[1])
+			if err != nil || ansi32 < -1 || ansi32 > 255 {
+				fail()
+			}
+			ansi := int16(ansi32)
+			switch pair[0] {
+			case "fg":
+				theme.Fg = ansi
+				theme.UseDefault = theme.UseDefault && ansi < 0
+			case "bg":
+				theme.Bg = ansi
+				theme.UseDefault = theme.UseDefault && ansi < 0
+			case "fg+":
+				theme.Current = ansi
+			case "bg+":
+				theme.DarkBg = ansi
+			case "hl":
+				theme.Match = ansi
+			case "hl+":
+				theme.CurrentMatch = ansi
+			case "prompt":
+				theme.Prompt = ansi
+			case "spinner":
+				theme.Spinner = ansi
+			case "info":
+				theme.Info = ansi
+			case "pointer":
+				theme.Cursor = ansi
+			case "marker":
+				theme.Selected = ansi
+			default:
+				fail()
+			}
+		}
 	}
-	return nil
+	return theme
 }
 
 func parseKeymap(keymap map[int]actionType, toggleSort bool, str string) (map[int]actionType, bool) {
@@ -400,7 +460,12 @@ func parseOptions(opts *Options, allArgs []string) {
 		case "--bind":
 			opts.Keymap, opts.ToggleSort = parseKeymap(opts.Keymap, opts.ToggleSort, nextString(allArgs, &i, "bind expression required"))
 		case "--color":
-			opts.Theme = parseTheme(nextString(allArgs, &i, "color scheme name required"))
+			spec := optionalNextString(allArgs, &i)
+			if len(spec) == 0 {
+				opts.Theme = defaultTheme()
+			} else {
+				opts.Theme = parseTheme(opts.Theme, spec)
+			}
 		case "--toggle-sort":
 			opts.Keymap = checkToggleSort(opts.Keymap, nextString(allArgs, &i, "key name required"))
 			opts.ToggleSort = true
@@ -497,7 +562,7 @@ func parseOptions(opts *Options, allArgs []string) {
 			} else if match, value := optString(arg, "--tiebreak="); match {
 				opts.Tiebreak = parseTiebreak(value)
 			} else if match, value := optString(arg, "--color="); match {
-				opts.Theme = parseTheme(value)
+				opts.Theme = parseTheme(opts.Theme, value)
 			} else if match, value := optString(arg, "--bind="); match {
 				opts.Keymap, opts.ToggleSort = parseKeymap(opts.Keymap, opts.ToggleSort, value)
 			} else {
diff --git a/src/options_test.go b/src/options_test.go
index ad9a6fb5..d3562108 100644
--- a/src/options_test.go
+++ b/src/options_test.go
@@ -155,3 +155,49 @@ func TestBind(t *testing.T) {
 	}
 	check(actAbort, keymap[curses.F1])
 }
+
+func TestColorSpec(t *testing.T) {
+	theme := curses.Dark256
+	dark := parseTheme(theme, "dark")
+	if *dark != *theme {
+		t.Errorf("colors should be equivalent")
+	}
+	if dark == theme {
+		t.Errorf("point should not be equivalent")
+	}
+
+	light := parseTheme(theme, "dark,light")
+	if *light == *theme {
+		t.Errorf("should not be equivalent")
+	}
+	if *light != *curses.Light256 {
+		t.Errorf("colors should be equivalent")
+	}
+	if light == theme {
+		t.Errorf("point should not be equivalent")
+	}
+
+	customized := parseTheme(theme, "fg:231,bg:232")
+	if customized.Fg != 231 || customized.Bg != 232 {
+		t.Errorf("color not customized")
+	}
+	if *curses.Dark256 == *customized {
+		t.Errorf("colors should not be equivalent")
+	}
+	customized.Fg = curses.Dark256.Fg
+	customized.Bg = curses.Dark256.Bg
+	if *curses.Dark256 == *customized {
+		t.Errorf("colors should now be equivalent")
+	}
+
+	customized = parseTheme(theme, "fg:231,dark,bg:232")
+	if customized.Fg != curses.Dark256.Fg || customized.Bg == curses.Dark256.Bg {
+		t.Errorf("color not customized")
+	}
+	if customized.UseDefault {
+		t.Errorf("not using default colors")
+	}
+	if !curses.Dark256.UseDefault {
+		t.Errorf("using default colors")
+	}
+}