Rename to Bubbles + copy over components from Bubble Tea + remove examples

viewport/viewport.go

@@ -0,0 +1,169 @@
+package viewport
+
+import (
+	"strings"
+
+	tea "github.com/charmbracelet/bubbletea"
+)
+
+// MODEL
+
+type Model struct {
+	Err    error
+	Width  int
+	Height int
+	Y      int
+
+	lines []string
+}
+
+// Scrollpercent returns the amount scrolled as a float between 0 and 1.
+func (m Model) ScrollPercent() float64 {
+	if m.Height >= len(m.lines) {
+		return 1.0
+	}
+	y := float64(m.Y)
+	h := float64(m.Height)
+	t := float64(len(m.lines))
+	return y / (t - h)
+}
+
+// SetContent set the pager's text content.
+func (m *Model) SetContent(s string) {
+	s = strings.Replace(s, "\r\n", "\n", -1) // normalize line endings
+	m.lines = strings.Split(s, "\n")
+}
+
+// NewModel creates a new pager model. Pass the dimensions of the pager.
+func NewModel(width, height int) Model {
+	return Model{
+		Width:  width,
+		Height: height,
+	}
+}
+
+// ViewDown moves the view down by the number of lines in the viewport.
+// Basically, "page down".
+func (m *Model) ViewDown() {
+	m.Y = min(len(m.lines)-m.Height, m.Y+m.Height)
+}
+
+// ViewUp moves the view up by one height of the viewport. Basically, "page up".
+func (m *Model) ViewUp() {
+	m.Y = max(0, m.Y-m.Height)
+}
+
+// HalfViewUp moves the view up by half the height of the viewport.
+func (m *Model) HalfViewUp() {
+	m.Y = max(0, m.Y-m.Height/2)
+}
+
+// HalfViewDown moves the view down by half the height of the viewport.
+func (m *Model) HalfViewDown() {
+	m.Y = min(len(m.lines)-m.Height, m.Y+m.Height/2)
+}
+
+// LineDown moves the view up by the given number of lines.
+func (m *Model) LineDown(n int) {
+	m.Y = min(len(m.lines)-m.Height, m.Y+n)
+}
+
+// LineDown moves the view down by the given number of lines.
+func (m *Model) LineUp(n int) {
+	m.Y = max(0, m.Y-n)
+}
+
+// UPDATE
+
+// Update runs the update loop with default keybindings. To define your own
+// keybindings use the methods on Model.
+func Update(msg tea.Msg, m Model) (Model, tea.Cmd) {
+	switch msg := msg.(type) {
+
+	case tea.KeyMsg:
+		switch msg.String() {
+		// Down one page
+		case "pgdown":
+			fallthrough
+		case " ": // spacebar
+			fallthrough
+		case "f":
+			m.ViewDown()
+			return m, nil
+
+		// Up one page
+		case "pgup":
+			fallthrough
+		case "b":
+			m.ViewUp()
+			return m, nil
+
+		// Down half page
+		case "d":
+			m.HalfViewDown()
+			return m, nil
+
+		// Up half page
+		case "u":
+			m.HalfViewUp()
+			return m, nil
+
+		// Down one line
+		case "down":
+			fallthrough
+		case "j":
+			m.LineDown(1)
+			return m, nil
+
+		// Up one line
+		case "up":
+			fallthrough
+		case "k":
+			m.LineUp(1)
+			return m, nil
+		}
+	}
+
+	return m, nil
+}
+
+// VIEW
+
+// View renders the viewport into a string.
+func View(m Model) string {
+	if m.Err != nil {
+		return m.Err.Error()
+	}
+
+	var lines []string
+
+	if len(m.lines) > 0 {
+		top := max(0, m.Y)
+		bottom := min(len(m.lines), m.Y+m.Height)
+		lines = m.lines[top:bottom]
+	}
+
+	// Fill empty space with newlines
+	extraLines := ""
+	if len(lines) < m.Height {
+		extraLines = strings.Repeat("\n", m.Height-len(lines))
+	}
+
+	return strings.Join(lines, "\n") + extraLines
+}
+
+// ETC
+
+func min(a, b int) int {
+	if a < b {
+		return a
+	}
+	return b
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}