Init

Signed-off-by: Hadi <112569860+anotherhadi@users.noreply.github.com>

internal/ui/diff/model.go

@@ -0,0 +1,264 @@
+package diff
+
+import (
+	"strings"
+
+	"charm.land/bubbles/v2/help"
+	"charm.land/bubbles/v2/key"
+	"charm.land/bubbles/v2/viewport"
+	tea "charm.land/bubbletea/v2"
+	"charm.land/lipgloss/v2"
+	"github.com/anotherhadi/spilltea/internal/keys"
+	"github.com/anotherhadi/spilltea/internal/style"
+)
+
+type slot struct {
+	label string
+	raw   string
+}
+
+type focusedSlot int
+
+const (
+	bothSlots focusedSlot = iota
+	leftSlot
+	rightSlot
+)
+
+func (f focusedSlot) next() focusedSlot {
+	return (f + 1) % 3
+}
+
+type lineKind int
+
+const (
+	lineUnchanged lineKind = iota
+	lineAdded
+	lineRemoved
+)
+
+type diffLine struct {
+	text string
+	kind lineKind
+}
+
+type Model struct {
+	left  slot
+	right slot
+	focus focusedSlot
+
+	leftLines  []diffLine
+	rightLines []diffLine
+
+	leftViewport  viewport.Model
+	rightViewport viewport.Model
+	help          help.Model
+
+	width  int
+	height int
+}
+
+func New() Model {
+	return Model{
+		leftViewport:  style.NewViewport(),
+		rightViewport: style.NewViewport(),
+		help:          style.NewHelp(),
+	}
+}
+
+func (m Model) Init() tea.Cmd { return nil }
+
+// CurrentRaw returns the raw content of the focused slot (left when both are focused).
+func (m Model) CurrentRaw() string {
+	if m.focus == rightSlot {
+		return m.right.raw
+	}
+	return m.left.raw
+}
+
+func (m *Model) SetSize(w, h int) {
+	m.width = w
+	m.height = h
+	m.recalcSizes()
+}
+
+func (m *Model) recalcSizes() {
+	m.help.SetWidth(m.width - 2)
+
+	statusH := strings.Count(m.renderStatusBar(), "\n") + 1
+	panelH := m.height - statusH
+	if panelH < 0 {
+		panelH = 0
+	}
+
+	leftW := m.width / 2
+	rightW := m.width - leftW
+
+	leftInner := leftW - 2
+	rightInner := rightW - 2
+	if leftInner < 0 {
+		leftInner = 0
+	}
+	if rightInner < 0 {
+		rightInner = 0
+	}
+
+	viewportH := style.PanelContentH(panelH)
+
+	m.leftViewport.SetWidth(leftInner)
+	m.leftViewport.SetHeight(viewportH)
+	m.rightViewport.SetWidth(rightInner)
+	m.rightViewport.SetHeight(viewportH)
+
+	m.refreshViewports()
+}
+
+func (m *Model) computeDiff() {
+	if m.left.raw == "" || m.right.raw == "" {
+		m.leftLines = nil
+		m.rightLines = nil
+		return
+	}
+	leftNorm := normRaw(m.left.raw)
+	rightNorm := normRaw(m.right.raw)
+	leftPlain := strings.Split(leftNorm, "\n")
+	rightPlain := strings.Split(rightNorm, "\n")
+	leftHL := hlLines(leftNorm)
+	rightHL := hlLines(rightNorm)
+	m.leftLines, m.rightLines = lcsAlignedDiff(leftPlain, rightPlain, leftHL, rightHL)
+}
+
+func normRaw(s string) string {
+	s = strings.ReplaceAll(s, "\r\n", "\n")
+	s = strings.ReplaceAll(s, "\r", "\n")
+	return strings.TrimRight(s, "\n")
+}
+
+func hlLines(raw string) []string {
+	s := strings.TrimRight(style.HighlightHTTP(raw), "\n")
+	if s == "" {
+		return nil
+	}
+	return strings.Split(s, "\n")
+}
+
+func (m *Model) refreshViewports() {
+	s := style.S
+
+	if m.left.raw == "" {
+		placeholder := lipgloss.Place(
+			m.leftViewport.Width(), m.leftViewport.Height(),
+			lipgloss.Center, lipgloss.Center,
+			s.Faint.Render("             <(^_^)>\nsend two entries here to compare"),
+		)
+		m.leftViewport.SetContent(placeholder)
+		m.rightViewport.SetContent("")
+		return
+	}
+
+	if m.right.raw == "" {
+		m.leftViewport.SetContent(style.HighlightHTTP(normRaw(m.left.raw)))
+		placeholder := lipgloss.Place(
+			m.rightViewport.Width(), m.rightViewport.Height(),
+			lipgloss.Center, lipgloss.Center,
+			s.Faint.Render("          (・3・)\nwaiting for second entry…"),
+		)
+		m.rightViewport.SetContent(placeholder)
+		return
+	}
+
+	m.leftViewport.SetContent(renderLeftLines(m.leftLines))
+	m.rightViewport.SetContent(renderRightLines(m.rightLines))
+}
+
+func (m *Model) scroll(delta int) {
+	offset := m.leftViewport.YOffset() + delta
+	m.leftViewport.SetYOffset(offset)
+	m.rightViewport.SetYOffset(offset)
+}
+
+func (m *Model) scrollH(delta int) {
+	offset := m.leftViewport.XOffset() + delta
+	m.leftViewport.SetXOffset(offset)
+	m.rightViewport.SetXOffset(offset)
+}
+
+func lcsAlignedDiff(a, b, aHL, bHL []string) (left, right []diffLine) {
+	hlA := func(i int) string {
+		if i < len(aHL) {
+			return aHL[i]
+		}
+		return a[i]
+	}
+	hlB := func(j int) string {
+		if j < len(bHL) {
+			return bHL[j]
+		}
+		return b[j]
+	}
+
+	n, m := len(a), len(b)
+
+	dp := make([][]int, n+1)
+	for i := range dp {
+		dp[i] = make([]int, m+1)
+	}
+	for i := 1; i <= n; i++ {
+		for j := 1; j <= m; j++ {
+			if a[i-1] == b[j-1] {
+				dp[i][j] = dp[i-1][j-1] + 1
+			} else if dp[i-1][j] >= dp[i][j-1] {
+				dp[i][j] = dp[i-1][j]
+			} else {
+				dp[i][j] = dp[i][j-1]
+			}
+		}
+	}
+
+	left = make([]diffLine, 0, n+m)
+	right = make([]diffLine, 0, n+m)
+	i, j := n, m
+	for i > 0 || j > 0 {
+		switch {
+		case i > 0 && j > 0 && a[i-1] == b[j-1]:
+			left = append(left, diffLine{text: hlA(i-1), kind: lineUnchanged})
+			right = append(right, diffLine{text: hlB(j-1), kind: lineUnchanged})
+			i--
+			j--
+		case j > 0 && (i == 0 || dp[i][j-1] >= dp[i-1][j]):
+			left = append(left, diffLine{kind: lineAdded})
+			right = append(right, diffLine{text: hlB(j-1), kind: lineAdded})
+			j--
+		default:
+			left = append(left, diffLine{text: hlA(i-1), kind: lineRemoved})
+			right = append(right, diffLine{kind: lineRemoved})
+			i--
+		}
+	}
+
+	for lo, hi := 0, len(left)-1; lo < hi; lo, hi = lo+1, hi-1 {
+		left[lo], left[hi] = left[hi], left[lo]
+		right[lo], right[hi] = right[hi], right[lo]
+	}
+	return left, right
+}
+
+func diffBindings() []key.Binding {
+	g := keys.Keys.Global
+	return []key.Binding{
+		g.Up, g.Down, g.ScrollUp, g.ScrollDown,
+		g.CycleFocus, keys.Keys.Diff.Clear,
+	}
+}
+
+type diffKeyMap struct{ width int }
+
+func (diffKeyMap) ShortHelp() []key.Binding {
+	g := keys.Keys.Global
+	return []key.Binding{g.Up, g.Down, g.CycleFocus, keys.Keys.Diff.Clear, g.Help}
+}
+
+func (m diffKeyMap) FullHelp() [][]key.Binding {
+	all := append(diffBindings(), keys.Keys.Global.Bindings()...)
+	return keys.ChunkByWidth(all, m.width)
+}