feat(progress): add a progression bar

tui/components/progress/progress.go

@@ -0,0 +1,125 @@
+// Package progress provides an animated progress bar
+package progress
+
+import (
+	"strings"
+	"sync/atomic"
+	"time"
+
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+	"go.uber.org/zap"
+)
+
+var lastID int64
+
+func nextID() int64 {
+	return atomic.AddInt64(&lastID, 1)
+}
+
+// FrameMsg is a message that is sent on every progress frame tick
+type FrameMsg struct {
+	id int64
+}
+
+// StartMsg is a message that starts the progress bar
+type StartMsg struct {
+	width       int
+	widthTarget int
+	interval    time.Duration
+}
+
+// Model for the progress component
+type Model struct {
+	id           int64
+	width        int
+	widthTarget  int
+	interval     time.Duration
+	styleFainted lipgloss.Style
+	styleGlow    lipgloss.Style
+}
+
+// New creates a new progress
+func New(styleFainted, styleGlow lipgloss.Style) Model {
+	zap.S().Info(styleFainted)
+	return Model{id: nextID(), styleFainted: styleFainted, styleGlow: styleGlow}
+}
+
+// Init initializes the progress component
+func (m Model) Init() tea.Cmd {
+	zap.S().Info(m.styleFainted)
+	return nil
+}
+
+// Start starts a progress bar until it reaches a given width in a given duration
+func (m Model) Start(width int, runningTime time.Duration, duration time.Duration) tea.Cmd {
+	zap.S().Info(m.styleFainted)
+	return func() tea.Msg {
+		interval := (duration / 2) / time.Duration(width)
+
+		return StartMsg{
+			width:       int(runningTime / interval),
+			widthTarget: width * 2,
+			interval:    interval,
+		}
+	}
+}
+
+// Update handles the progress frame tick
+func (m Model) Update(msg tea.Msg) (Model, tea.Cmd) {
+	zap.S().Info(m.styleFainted)
+	switch msg := msg.(type) {
+	case FrameMsg:
+		if msg.id != m.id {
+			return m, nil
+		}
+
+		m.width++
+
+		if m.width < m.widthTarget {
+			return m, tick(m.id, m.interval)
+		}
+
+		return m, nil
+
+	case StartMsg:
+		m.id = nextID()
+		m.width = msg.width
+		m.widthTarget = msg.widthTarget
+		m.interval = msg.interval
+
+		return m, tick(m.id, m.interval)
+	}
+
+	return m, nil
+}
+
+// View of the progress bar component
+func (m Model) View() string {
+	zap.S().Info(m.styleFainted)
+	glowCount := min(20, m.width)
+	// Make sure if m.width is uneven that the half block string is in the glow part
+	if m.width%2 == 1 && glowCount%2 == 0 {
+		glowCount--
+	}
+	faintedCount := m.width - glowCount
+
+	// Construct fainted
+	fainted := strings.Repeat("▄", faintedCount/2)
+	fainted = m.styleFainted.Render(fainted)
+
+	// Construct glow
+	glow := strings.Repeat("▄", glowCount/2)
+	if glowCount%2 == 1 {
+		glow += "▖"
+	}
+	glow = m.styleGlow.Render(glow)
+
+	return lipgloss.JoinHorizontal(lipgloss.Top, fainted, glow)
+}
+
+func tick(id int64, interval time.Duration) tea.Cmd {
+	return tea.Tick(interval, func(_ time.Time) tea.Msg {
+		return FrameMsg{id: id}
+	})
+}