v0.30.0 lw --tui, compose pipeline on screen

internal/tui/theme.go

@@ -0,0 +1,114 @@
+package tui
+
+import (
+	"os"
+	"strings"
+	"unicode"
+
+	"github.com/lixenwraith/color"
+	"github.com/lixenwraith/terminal"
+	ui "github.com/lixenwraith/terminal/tui"
+)
+
+// look is a color tier's styles: the widgets' theme and each column's tint
+type look struct {
+	ui.Theme
+	Source, Flow, Sink ui.Style
+}
+
+// The site's dark tokens; true color and 256 colors paint its background
+var (
+	siteBg     = color.RGB{R: 0x14, G: 0x17, B: 0x1d}
+	sitePanel  = color.RGB{R: 0x1c, G: 0x20, B: 0x28}
+	siteFg     = color.RGB{R: 0xe3, G: 0xe7, B: 0xef}
+	siteMuted  = color.RGB{R: 0x9a, G: 0xa3, B: 0xb5}
+	siteAccent = color.RGB{R: 0x6e, G: 0xa0, B: 0xff}
+)
+
+var siteLook = look{
+	Theme: ui.Theme{
+		Text:     ui.Style{Fg: siteFg, Bg: siteBg},
+		Muted:    ui.Style{Fg: siteMuted},
+		Accent:   ui.Style{Fg: siteAccent, Attr: terminal.AttrBold},
+		Selected: ui.Style{Bg: color.RGB{R: 0x26, G: 0x2c, B: 0x38}},
+		Input:    ui.Style{Bg: sitePanel},
+		Cursor:   ui.Style{Fg: siteBg, Bg: siteFg},
+		Error:    ui.Style{Fg: color.RGB{R: 0xff, G: 0x6b, B: 0x6b}},
+		Border:   ui.Style{Fg: color.RGB{R: 0x5a, G: 0x63, B: 0x75}},
+	},
+	Source: ui.Style{Fg: color.RGB{R: 0x56, G: 0xc8, B: 0xd8}},
+	Flow:   ui.Style{Fg: color.RGB{R: 0xb1, G: 0x8c, B: 0xff}},
+	Sink:   ui.Style{Fg: color.RGB{R: 0x6f, G: 0xcf, B: 0x8f}},
+}
+
+// ansi is a palette index the terminal shows in its own shade
+func ansi(i uint8) ui.Style { return ui.Style{Fg: color.RGB{R: i}, Attr: terminal.AttrFg256} }
+
+// looks holds one look per color tier: 16 colors and none keep the
+// terminal's background
+var looks = map[terminal.ColorMode]look{
+	terminal.ColorModeTrueColor: siteLook,
+	terminal.ColorMode256:       siteLook,
+	terminal.ColorMode16: {Theme: ui.Theme16,
+		Source: ansi(color.ANSICyan), Flow: ansi(color.ANSIMagenta), Sink: ansi(color.ANSIGreen)},
+	terminal.ColorModeNone: {Theme: ui.MonoTheme,
+		Source: ui.MonoTheme.Text, Flow: ui.MonoTheme.Text, Sink: ui.MonoTheme.Text},
+}
+
+// font is the marks one character set draws: the widgets' and the canvas's
+type font struct {
+	ui.Glyphs
+	wire        []rune // a wire cell by its arms: up 1, right 2, down 4, left 8
+	box         []rune // the flow box: top left, top right, bottom left, bottom right, across, down
+	arrow, down rune   // into the flow box and a sink; between stacked parts
+	bar, barOn  rune   // a node, and the chosen node
+	dot, rule   rune   // before a column's title; the inspector's rule
+	valid       string
+	invalid     string
+	enter       string
+	space       string
+	folds       map[rune]rune // runes its terminal lacks, by the rune drawn instead
+	ascii       bool          // past ASCII, any other rune draws as '?'
+}
+
+// fold is r as the font's terminal shows it: the library truncates with '…'
+// and the inspector's titles join with '·'
+func (f font) fold(r rune) rune {
+	if to, ok := f.folds[r]; ok {
+		return to
+	}
+	if f.ascii && r > unicode.MaxASCII {
+		return '?'
+	}
+	return r
+}
+
+// fonts: Unicode, a text console's CP437, and ASCII outside UTF-8
+var (
+	unicodeFont = font{Glyphs: ui.GlyphsUnicode, wire: []rune(" │─└││┌├─┘─┴┐┤┬┼"), box: []rune("╭╮╰╯╌╎"),
+		arrow: '►', down: '▼', bar: '▌', barOn: '█', dot: '●', rule: '─', valid: "✓", invalid: "✗", enter: "⏎", space: "␣"}
+	cp437Font = font{Glyphs: ui.GlyphsCP437, wire: []rune(" │─└││┌├─┘─┴┐┤┬┼"), box: []rune("┌┐└┘─│"),
+		arrow: '►', down: '▼', bar: '▌', barOn: '█', dot: '•', rule: '─', valid: "√", invalid: "x", enter: "enter", space: "space",
+		folds: map[rune]rune{'…': '.'}}
+	asciiFont = font{Glyphs: ui.GlyphsASCII, wire: []rune(" |-+||++-+-+++++"), box: []rune("++++-|"),
+		arrow: '>', down: 'v', bar: '|', barOn: '#', dot: '*', rule: '-', valid: "ok", invalid: "x", enter: "enter", space: "space",
+		folds: map[rune]rune{'…': '.', '·': '-'}, ascii: true}
+)
+
+// fontFor picks ASCII outside a UTF-8 locale, CP437 on a text console (the
+// terminals with 16 colors), Unicode elsewhere
+func fontFor(detected terminal.ColorMode) font {
+	locale := ""
+	for _, name := range []string{"LC_ALL", "LC_CTYPE", "LANG"} {
+		if locale = os.Getenv(name); locale != "" {
+			break
+		}
+	}
+	switch l := strings.ToLower(locale); {
+	case l != "" && !strings.Contains(l, "utf-8") && !strings.Contains(l, "utf8"):
+		return asciiFont
+	case detected == terminal.ColorMode16:
+		return cp437Font
+	}
+	return unicodeFont
+}