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chore: overhaul spinner
commit5df4167d15df40865411b900348bbea0299fd00b authorChristian Rocha <christian@rocha.is> dateWed 2 Jul 2025, 12:18 (1 year ago) parentb738f51
2 files changed+230−252
internal/tui/components/anim/anim.go+162−252 internal/tui/components/anim/example/main.go+68
internal/tui/components/anim/anim.go+162−252
@@ -1,3 +1,4 @@
1+// Package anim provides an animated spinner.
12package anim
23
34import (
@@ -5,302 +6,211 @@ import (
56 "image/color"
67 "math/rand/v2"
78 "strings"
9+ "sync/atomic"
810 "time"
911
10− "github.com/charmbracelet/bubbles/v2/spinner"
1112 tea "github.com/charmbracelet/bubbletea/v2"
1213 "github.com/charmbracelet/crush/internal/tui/styles"
13− "github.com/charmbracelet/crush/internal/tui/util"
1414 "github.com/charmbracelet/lipgloss/v2"
15− "github.com/google/uuid"
1615 "github.com/lucasb-eyer/go-colorful"
1716)
1817
1918const (
20− charCyclingFPS = time.Second / 22
21− colorCycleFPS = time.Second / 5
22− maxCyclingChars = 60
19+ fps = 20
20+ initialChar = '.'
21+ labelGap = " "
22+ labelGapWidth = 1
23+
24+ // Periods of ellipsis animation speed in steps.
25+ //
26+ // If the FPS is 20 (50 milliseconds) this means that the ellipsis will
27+ // change every 8 frames (400 milliseconds).
28+ ellipsisAnimSpeed = 8
29+
30+ // The maximum amount of time that can pass before a character appears.
31+ // This is used to create a staggered entrance effect.
32+ maxBirthOffset = time.Second
33+
34+ // Number of frames to prerender for the animation. After this number
35+ // of frames, the animation will loop.
36+ prerenderedFrames = 10
2337)
2438
2539var (
26− charRunes = []rune("0123456789abcdefABCDEF~!@#$£€%^&*()+=_")
27− charRunePool = make([]rune, 1000) // Pre-generated pool of random characters
28− poolIndex = 0
40+ availableRunes = []rune("0123456789abcdefABCDEF~!@#$£€%^&*()+=_")
41+ ellipsisFrames = []string{".", "..", "...", ""}
2942)
3043
31−func init() {
32− // Pre-populate the character pool to avoid runtime random generation.
33− for i := range charRunePool {
34− charRunePool[i] = charRunes[rand.IntN(len(charRunes))]
35− }
36−}
37−
38−type charState int
39−
40−const (
41− charInitialState charState = iota
42− charCyclingState
43− charEndOfLifeState
44−)
45−
46−// cyclingChar is a single animated character.
47−type cyclingChar struct {
48− finalValue rune // if < 0 cycle forever
49− currentValue rune
50− initialDelay time.Duration
51− lifetime time.Duration
52−}
53−
54−func (c cyclingChar) randomRune() rune {
55− // Use pre-generated pool instead of runtime random generation.
56− poolIndex = (poolIndex + 1) % len(charRunePool)
57− return charRunePool[poolIndex]
58−}
59−
60−func (c cyclingChar) state(start time.Time) charState {
61− now := time.Now()
62− if now.Before(start.Add(c.initialDelay)) {
63− return charInitialState
64− }
65− if c.finalValue > 0 && now.After(start.Add(c.initialDelay)) {
66− return charEndOfLifeState
67− }
68− return charCyclingState
69−}
70−
71−type StepCharsMsg struct {
72− id string
73−}
74−
75−func stepChars(id string) tea.Cmd {
76− return tea.Tick(charCyclingFPS, func(time.Time) tea.Msg {
77− return StepCharsMsg{id}
78− })
79−}
80−
81−type ColorCycleMsg struct {
82− id string
83−}
84−
85−func cycleColors(id string) tea.Cmd {
86− return tea.Tick(colorCycleFPS, func(time.Time) tea.Msg {
87− return ColorCycleMsg{id}
88− })
89−}
90−
91−type Animation interface {
92− util.Model
93− ID() string
94−}
95−
96−// anim is the model that manages the animation that displays while the
97−// output is being generated.
98−type anim struct {
99− start time.Time
100− cyclingChars []cyclingChar
101− labelChars []cyclingChar
102− ramp []lipgloss.Style
103− label []rune
104− ellipsis spinner.Model
105− ellipsisStarted bool
106− id string
107−}
108−
109−type animOption func(*anim)
110−
111−func WithId(id string) animOption {
112− return func(a *anim) {
113− a.id = id
114− }
115−}
116−
117−func New(cyclingCharsSize uint, label string, opts ...animOption) Animation {
118− // #nosec G115
119− n := min(int(cyclingCharsSize), maxCyclingChars)
120−
121− gap := " "
122− if n == 0 {
123− gap = ""
124− }
125−
126− id := uuid.New()
127− c := anim{
128− start: time.Now(),
129− label: []rune(gap + label),
130− ellipsis: spinner.New(spinner.WithSpinner(spinner.Ellipsis)),
131− id: id.String(),
132− }
133−
134− for _, opt := range opts {
135− opt(&c)
136− }
137−
138− // If we're in truecolor mode (and there are enough cycling characters)
139− // color the cycling characters with a gradient ramp.
140− const minRampSize = 3
141− if n >= minRampSize {
142− // Optimized: single capacity allocation for color cycling.
143− c.ramp = make([]lipgloss.Style, 0, n*2)
144− ramp := makeGradientRamp(n)
145− for _, color := range ramp {
146− c.ramp = append(c.ramp, lipgloss.NewStyle().Foreground(color))
147− }
148− // Create reversed copy for seamless color cycling.
149− reversed := make([]lipgloss.Style, len(c.ramp))
150− for i, style := range c.ramp {
151− reversed[len(c.ramp)-1-i] = style
44+// Internal ID management. Used during animating to ensure that frame messages
45+// are received only by spinner components that sent them.
46+var lastID int64
47+
48+func nextID() int {
49+ return int(atomic.AddInt64(&lastID, 1))
50+}
51+
52+// StepMsg is a message type used to trigger the next step in the animation.
53+type StepMsg struct{ id int }
54+
55+// Anim is a Bubble for an animated spinner.
56+type Anim struct {
57+ width int
58+ cyclingCharWidth int
59+ label []string
60+ labelWidth int
61+ startTime time.Time
62+ birthOffsets []time.Duration
63+ initialChars []string
64+ initialized bool
65+ cyclingFrames [][]string // frames for the cycling characters
66+ step int // current main frame step
67+ ellipsisStep int // current ellipsis frame step
68+ ellipsisFrames []string // ellipsis animation frames
69+ id int
70+}
71+
72+// New creates a new Anim instance with the specified width and label.
73+func New(numChars int, label string, t *styles.Theme) (a Anim) {
74+ a.id = nextID()
75+
76+ a.startTime = time.Now()
77+ a.cyclingCharWidth = numChars
78+ a.labelWidth = lipgloss.Width(label)
79+
80+ // Total width of anim, in cells.
81+ a.width = numChars
82+ if label != "" {
83+ a.width += labelGapWidth + lipgloss.Width(label)
84+ }
85+
86+ // Pre-render the label.
87+ // XXX: We should really get the graphemes for the label, not the runes.
88+ labelRunes := []rune(label)
89+ a.label = make([]string, len(labelRunes))
90+ for i := range a.label {
91+ a.label[i] = lipgloss.NewStyle().
92+ Foreground(t.FgBase).
93+ Render(string(labelRunes[i]))
94+ }
95+
96+ // Pre-generate gradient.
97+ ramp := makeGradientRamp(a.width, t.Primary, t.Secondary)
98+
99+ // Pre-render initial characters.
100+ a.initialChars = make([]string, a.width)
101+ for i := range a.initialChars {
102+ a.initialChars[i] = lipgloss.NewStyle().
103+ Foreground(ramp[i]).
104+ Render(string(initialChar))
105+ }
106+
107+ // Pre-render the ellipsis frames.
108+ a.ellipsisFrames = make([]string, len(ellipsisFrames))
109+ for i, frame := range ellipsisFrames {
110+ a.ellipsisFrames[i] = lipgloss.NewStyle().
111+ Foreground(t.FgBase).
112+ Render(frame)
113+ }
114+
115+ // Prerender scrambled rune frames for the animation.
116+ a.cyclingFrames = make([][]string, prerenderedFrames)
117+ for i := range a.cyclingFrames {
118+ a.cyclingFrames[i] = make([]string, a.width)
119+ for j := range a.cyclingFrames[i] {
120+ // NB: we also prerender the color with Lip Gloss here to avoid
121+ // processing in the render loop.
122+ r := availableRunes[rand.IntN(len(availableRunes))]
123+ a.cyclingFrames[i][j] = lipgloss.NewStyle().
124+ Foreground(ramp[j]).
125+ Render(string(r))
152126 }
153− c.ramp = append(c.ramp, reversed...)
154− }
155−
156− makeDelay := func(a int32, b time.Duration) time.Duration {
157− return time.Duration(rand.Int32N(a)) * (time.Millisecond * b) //nolint:gosec
158127 }
159128
160− makeInitialDelay := func() time.Duration {
161− return makeDelay(8, 60) //nolint:mnd
129+ // Random assign a birth to each character for a stagged entrance effect.
130+ a.birthOffsets = make([]time.Duration, a.width)
131+ for i := range a.birthOffsets {
132+ a.birthOffsets[i] = time.Duration(rand.N(int64(maxBirthOffset))) * time.Nanosecond
162133 }
163134
164− // Initial characters that cycle forever.
165− c.cyclingChars = make([]cyclingChar, n)
166−
167− for i := range n {
168− c.cyclingChars[i] = cyclingChar{
169− finalValue: -1, // cycle forever
170− initialDelay: makeInitialDelay(),
171− }
172− }
173−
174− // Label text that only cycles for a little while.
175− c.labelChars = make([]cyclingChar, len(c.label))
176−
177− for i, r := range c.label {
178− c.labelChars[i] = cyclingChar{
179− finalValue: r,
180− initialDelay: makeInitialDelay(),
181− lifetime: makeDelay(5, 180), //nolint:mnd
182− }
183− }
184−
185− return c
135+ return a
186136}
187137
188−// Init initializes the animation.
189−func (a anim) Init() tea.Cmd {
190− return tea.Batch(stepChars(a.id), cycleColors(a.id))
138+// Init starts the animation.
139+func (a Anim) Init() tea.Cmd {
140+ return a.Step()
191141}
192142
193−// Update handles messages.
194−func (a anim) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
195− var cmd tea.Cmd
143+// Update processes animation steps (or not).
144+func (a Anim) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
196145 switch msg := msg.(type) {
197− case StepCharsMsg:
146+ case StepMsg:
198147 if msg.id != a.id {
148+ // Reject messages that are not for this instance.
199149 return a, nil
200150 }
201− a.updateChars(&a.cyclingChars)
202− a.updateChars(&a.labelChars)
203151
204− if !a.ellipsisStarted {
205− var eol int
206− for _, c := range a.labelChars {
207− if c.state(a.start) == charEndOfLifeState {
208− eol++
209− }
210− }
211− if eol == len(a.label) {
212− // If our entire label has reached end of life, start the
213− // ellipsis "spinner" after a short pause.
214− a.ellipsisStarted = true
215− cmd = tea.Tick(time.Millisecond*220, func(time.Time) tea.Msg { //nolint:mnd
216− return a.ellipsis.Tick()
217− })
218− }
152+ a.step++
153+ if a.step >= len(a.cyclingFrames) {
154+ a.step = 0
219155 }
220156
221− return a, tea.Batch(stepChars(a.id), cmd)
222− case ColorCycleMsg:
223− if msg.id != a.id {
224− return a, nil
225− }
226− const minColorCycleSize = 2
227− if len(a.ramp) < minColorCycleSize {
228− return a, nil
157+ if a.initialized {
158+ // Manage the ellipsis animation.
159+ a.ellipsisStep++
160+ if a.ellipsisStep >= ellipsisAnimSpeed*len(ellipsisFrames) {
161+ a.ellipsisStep = 0
162+ }
163+ } else if !a.initialized && time.Since(a.startTime) >= maxBirthOffset {
164+ a.initialized = true
229165 }
230− a.ramp = append(a.ramp[1:], a.ramp[0])
231− return a, cycleColors(a.id)
232− case spinner.TickMsg:
233− var cmd tea.Cmd
234− a.ellipsis, cmd = a.ellipsis.Update(msg)
235− return a, cmd
166+ return a, a.Step()
236167 default:
237168 return a, nil
238169 }
239170}
240171
241−func (a anim) ID() string {
242− return a.id
243−}
244−
245−func (a *anim) updateChars(chars *[]cyclingChar) {
246− charSlice := *chars // dereference to avoid repeated pointer access
247− for i, c := range charSlice {
248− switch c.state(a.start) {
249− case charInitialState:
250− charSlice[i].currentValue = '.'
251− case charCyclingState:
252− charSlice[i].currentValue = c.randomRune()
253− case charEndOfLifeState:
254− charSlice[i].currentValue = c.finalValue
172+// View renders the current state of the animation.
173+func (a Anim) View() tea.View {
174+ var b strings.Builder
175+ for i := range a.width {
176+ switch {
177+ case !a.initialized && time.Since(a.startTime) < a.birthOffsets[i]:
178+ // Birth offset not reached: render initial character.
179+ b.WriteString(a.initialChars[i])
180+ case i < a.cyclingCharWidth:
181+ // Render a cycling character.
182+ b.WriteString(a.cyclingFrames[a.step][i])
183+ case i == a.cyclingCharWidth:
184+ // Render label gap.
185+ b.WriteString(labelGap)
186+ case i > a.cyclingCharWidth:
187+ // Label.
188+ b.WriteString(a.label[i-a.cyclingCharWidth-labelGapWidth])
255189 }
256190 }
257−}
258−
259−// View renders the animation.
260−func (a anim) View() tea.View {
261− var (
262− t = styles.CurrentTheme()
263− b strings.Builder
264− )
265−
266− // Optimized capacity calculation to reduce allocations.
267− const (
268− bytesPerChar = 15 // Reduced estimate for ANSI styling
269− bufferSize = 30 // Reduced safety margin
270− )
271− estimatedCap := len(a.cyclingChars)*bytesPerChar + len(a.labelChars)*bytesPerChar + bufferSize
272− b.Grow(estimatedCap)
273−
274− // Render cycling characters with gradient (if available).
275− for i, c := range a.cyclingChars {
276− if len(a.ramp) > i {
277− b.WriteString(a.ramp[i].Render(string(c.currentValue)))
278− } else {
279− b.WriteRune(c.currentValue)
280− }
281− }
282−
283− // Render label characters and ellipsis.
284− if len(a.labelChars) > 1 {
285− textStyle := t.S().Text
286− for _, c := range a.labelChars {
287− b.WriteString(textStyle.Render(string(c.currentValue)))
288− }
289− b.WriteString(textStyle.Render(a.ellipsis.View()))
191+ // Render animated ellipsis at the end of the label if all characters
192+ // have been initialized.
193+ if a.initialized {
194+ b.WriteString(a.ellipsisFrames[a.ellipsisStep/ellipsisAnimSpeed])
290195 }
291−
292196 return tea.NewView(b.String())
293197}
294198
295−func GetColor(c color.Color) string {
296− rgba := color.RGBAModel.Convert(c).(color.RGBA)
297− return fmt.Sprintf("#%02x%02x%02x", rgba.R, rgba.G, rgba.B)
199+// Step is a command that triggers the next step in the animation.
200+func (a Anim) Step() tea.Cmd {
201+ return tea.Tick(time.Second/time.Duration(fps), func(t time.Time) tea.Msg {
202+ return StepMsg{id: a.id}
203+ })
204+}
205+
206+func colorToHex(c color.Color) string {
207+ r, g, b, _ := c.RGBA()
208+ return fmt.Sprintf("#%02x%02x%02x", uint8(r>>8), uint8(g>>8), uint8(b>>8))
298209}
299210
300−func makeGradientRamp(length int) []color.Color {
301− t := styles.CurrentTheme()
302− startColor := GetColor(t.Primary)
303− endColor := GetColor(t.Secondary)
211+func makeGradientRamp(length int, from, to color.Color) []color.Color {
212+ startColor := colorToHex(from)
213+ endColor := colorToHex(to)
304214 var (
305215 c = make([]color.Color, length)
306216 start, _ = colorful.Hex(startColor)
internal/tui/components/anim/example/main.gonew file+68
@@ -0,0 +1,68 @@
1+package main
2+
3+import (
4+ "fmt"
5+ "image/color"
6+ "os"
7+
8+ tea "github.com/charmbracelet/bubbletea/v2"
9+ anim "github.com/charmbracelet/crush/internal/tui/components/anim"
10+ "github.com/charmbracelet/crush/internal/tui/styles"
11+)
12+
13+type model struct {
14+ anim tea.Model
15+ bgColor color.Color
16+ quitting bool
17+}
18+
19+func (m model) Init() tea.Cmd {
20+ return m.anim.Init()
21+}
22+
23+func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
24+ switch msg := msg.(type) {
25+ case tea.KeyMsg:
26+ switch msg.String() {
27+ case "q", "ctrl+c":
28+ m.quitting = true
29+ return m, tea.Quit
30+ default:
31+ return m, nil
32+ }
33+ case anim.StepMsg:
34+ var cmd tea.Cmd
35+ m.anim, cmd = m.anim.Update(msg)
36+ return m, cmd
37+ default:
38+ return m, nil
39+ }
40+}
41+
42+func (m model) View() tea.View {
43+ // XXX tea.View() needs a content setter.
44+ v := tea.NewView("")
45+ v.SetBackgroundColor(m.bgColor)
46+ if m.quitting {
47+ return v
48+ }
49+ if a, ok := m.anim.(anim.Anim); ok {
50+ v = tea.NewView(a.View().String() + "\n")
51+ v.SetBackgroundColor(m.bgColor)
52+ return v
53+ }
54+ return v
55+}
56+
57+func main() {
58+ t := styles.CurrentTheme()
59+ p := tea.NewProgram(model{
60+ bgColor: t.BgBase,
61+ anim: anim.New(50, "Hello", t),
62+ })
63+
64+ if _, err := p.Run(); err != nil {
65+ fmt.Fprintf(os.Stderr, "Uh oh: %v\n", err)
66+ os.Exit(1)
67+ }
68+}