Files
patterm/internal/app/toast.go
Harry Bayliss cf65d5d707 Wrap toast bodies, slim the dismiss hint, and stop flicker
Toasts now render three content rows with word-wrapped bodies. The
in-toast "Ctrl-N · N more" hint is replaced by a short
"Ctrl-N · dismiss" entry on the status strip that only appears
while a notification is live.

The box stops flickering while the focused child repaints its TUI:
the overlay is stitched onto the per-chunk PTY write under outMu
and bracketed by DECSET 2026 so supporting terminals buffer the
child's redraw and the box paint into a single frame.
2026-05-15 21:24:18 +01:00

362 lines
9.6 KiB
Go

package app
import (
"os"
"strings"
"sync"
)
// toastKind classifies a toast for styling and for migrating the
// pre-existing flashError / flashTransient / notifyAttention call
// sites onto the new stack.
type toastKind int
const (
toastInfo toastKind = iota
toastError
toastAttention
)
// toast is one entry in the host-level notification stack. Toasts
// persist until the user dismisses them with Ctrl-N or the
// "Clear notifications" palette command — there's no auto-expiry.
type toast struct {
id uint64
kind toastKind
text string
}
// toastStackCap caps how many toasts can be visible at once.
// Older entries drop off the bottom when a new push would exceed it.
const toastStackCap = 5
// toastBoxMaxWidth bounds the rendered box width so a wide pane
// doesn't produce huge toasts. Boxes shrink below this when the pane
// is narrow.
const toastBoxMaxWidth = 50
// toastBoxMinWidth is the floor below which we refuse to render —
// any narrower and there's not enough room for borders + content.
const toastBoxMinWidth = 20
// toastContentRows is how many lines of message body each toast box
// reserves. The dismiss hint lives on the host status strip, so the
// box itself is purely the message.
const toastContentRows = 3
// toastStack owns the ordered list of live toasts. Oldest at
// index 0, newest (visually topmost) at the end. The stack's own
// mutex is intentionally separate from uiState.mu so push / dismiss
// can be called from any goroutine without participating in the
// host's bigger lock-ordering rules.
type toastStack struct {
mu sync.Mutex
items []toast
next uint64
}
func (s *toastStack) push(kind toastKind, text string) {
s.mu.Lock()
defer s.mu.Unlock()
s.next++
s.items = append(s.items, toast{id: s.next, kind: kind, text: text})
if len(s.items) > toastStackCap {
s.items = s.items[len(s.items)-toastStackCap:]
}
}
// dismissTop pops the most recent toast (the one rendered at the
// top of the stack). Returns true if something was removed so
// callers can decide whether to repaint.
func (s *toastStack) dismissTop() bool {
s.mu.Lock()
defer s.mu.Unlock()
if len(s.items) == 0 {
return false
}
s.items = s.items[:len(s.items)-1]
return true
}
func (s *toastStack) clear() bool {
s.mu.Lock()
defer s.mu.Unlock()
if len(s.items) == 0 {
return false
}
s.items = s.items[:0]
return true
}
func (s *toastStack) snapshot() []toast {
s.mu.Lock()
defer s.mu.Unlock()
if len(s.items) == 0 {
return nil
}
out := make([]toast, len(s.items))
copy(out, s.items)
return out
}
func (s *toastStack) length() int {
s.mu.Lock()
defer s.mu.Unlock()
return len(s.items)
}
// notifyToast is the single entry point that the former flash
// helpers now delegate to. It pushes onto the stack and triggers a
// repaint of the focused surface so the new toast appears
// immediately; the repaint path also re-renders the stack on top.
func (st *uiState) notifyToast(kind toastKind, text string) {
st.toasts.push(kind, text)
st.refreshToastSurface()
}
// refreshToastSurface re-renders whatever surface the toasts are
// drawn over (focused child, focused pad, or the empty-state
// canvas). Each of those paths calls renderToasts at the end, so
// the toast layer is always reapplied on top of a freshly-drawn
// pane. Centralised so push / dismiss / clear share one code path.
//
// The status strip also gains/loses the "Ctrl-N · dismiss" hint as
// the stack toggles between empty and non-empty, so we redraw it
// here too rather than waiting for the chrome ticker.
func (st *uiState) refreshToastSurface() {
st.mu.Lock()
focusedPad := st.focusedPad
focusedID := st.focusedID
palOpen := st.palette != nil
st.mu.Unlock()
if palOpen {
// Palette owns the whole screen while it's open; toasts will
// repaint via closePalette's restore path.
return
}
switch {
case focusedPad != "":
st.repaintFocusedPad()
case focusedID != "":
st.repaintFocused()
default:
st.renderEmptyState()
}
st.drawStatusLine()
}
// renderToasts draws the toast stack over the top-right of the
// focused pane. Called from repaintFocused / repaintFocusedPad /
// renderEmptyState after they finish so toasts always sit on top of
// freshly-redrawn pane content. Safe to call when the stack is
// empty (no-op).
func (st *uiState) renderToasts() {
bytes := st.toastOverlayBytes()
if len(bytes) == 0 {
return
}
st.outMu.Lock()
defer st.outMu.Unlock()
_, _ = os.Stdout.Write(bytes)
}
// toastOverlayBytes builds the toast layer as a single byte buffer
// without writing to stdout. Returns nil when the stack is empty or
// the layout can't accommodate a box. Callers either write it
// directly (renderToasts) or stitch it onto the end of another
// stdout write so claude/codex/opencode redraws that paint over the
// top-right region can't leave the toast half-erased.
func (st *uiState) toastOverlayBytes() []byte {
items := st.toasts.snapshot()
if len(items) == 0 {
return nil
}
st.mu.Lock()
palOpen := st.palette != nil
st.mu.Unlock()
if palOpen {
return nil
}
layout := st.layoutSnapshot()
paneCols := int(layout.childCols())
paneRows := int(layout.childRows())
if paneCols < toastBoxMinWidth+2 || paneRows < toastContentRows+2 {
return nil
}
boxWidth := toastBoxMaxWidth
if max := paneCols - 4; max < boxWidth {
boxWidth = max
}
if boxWidth < toastBoxMinWidth {
return nil
}
contentWidth := boxWidth - 4 // 2 border cells + 2 inner padding
// Reserve two columns for the icon prefix on row 1 so wrapped rows
// indent under the body text rather than under the glyph.
const iconCols = 2
bodyRoom := contentWidth - iconCols
if bodyRoom < 1 {
return nil
}
var b strings.Builder
// Wrap the whole overlay in DECSET 2026 (synchronized output)
// brackets so terminals that support BSU/ESU buffer the box paint
// into a single frame — without this, claude's continuous redraws
// and our overlay race on each cell, producing visible flicker.
// Terminals that don't recognise 2026 ignore the brackets, so the
// fallback behaviour is the same as before.
b.WriteString("\x1b[?2026h\x1b7\x1b[?25l")
row := int(layout.mainTop) + 1
col := int(layout.mainLeft) + paneCols - boxWidth - 1
if col < int(layout.mainLeft) {
col = int(layout.mainLeft)
}
// Render newest first (visually on top), iterating items in
// reverse so the most recent push lands at the smallest row.
for idx := len(items) - 1; idx >= 0; idx-- {
t := items[idx]
height := toastContentRows + 2
// Stop if we'd run off the bottom of the pane.
if row+height > int(layout.mainTop)+paneRows {
break
}
border := toastBorderStyle(t.kind)
wrapped := wrapToastBody(t.text, bodyRoom)
// Top border.
moveTo(&b, row, col)
b.WriteString(border)
b.WriteString("╭")
b.WriteString(strings.Repeat("─", boxWidth-2))
b.WriteString("╮")
b.WriteString(styleReset)
row++
// Content rows. Row 0 carries the kind glyph; rows 1..N indent
// by iconCols spaces so wrapped text lines up under the body.
for i := 0; i < toastContentRows; i++ {
moveTo(&b, row, col)
b.WriteString(border)
b.WriteString("│")
b.WriteString(styleReset)
b.WriteString(" ")
if i == 0 {
b.WriteString(toastIcon(t.kind))
} else {
b.WriteString(strings.Repeat(" ", iconCols))
}
line := wrapped[i]
b.WriteString(line)
b.WriteString(strings.Repeat(" ", max(0, bodyRoom-visibleLen(line))))
b.WriteString(" ")
b.WriteString(border)
b.WriteString("│")
b.WriteString(styleReset)
row++
}
// Bottom border.
moveTo(&b, row, col)
b.WriteString(border)
b.WriteString("╰")
b.WriteString(strings.Repeat("─", boxWidth-2))
b.WriteString("╯")
b.WriteString(styleReset)
row++
// 1-row gap between stacked toasts.
row++
}
b.WriteString("\x1b[?25h\x1b8\x1b[?2026l")
return []byte(b.String())
}
func toastBorderStyle(kind toastKind) string {
switch kind {
case toastError:
return styleError
case toastAttention:
return styleAccent
default:
return styleBorder
}
}
// wrapToastBody word-wraps text into exactly toastContentRows lines,
// each at most width visible runes wide. Short messages are padded
// with empty trailing lines so callers can iterate a fixed-size
// slice; messages that don't fit get ellipsized on the last line.
func wrapToastBody(text string, width int) []string {
out := make([]string, toastContentRows)
if width < 1 {
return out
}
all := wrapToastWords(text, width)
if len(all) > toastContentRows {
all = all[:toastContentRows]
last := all[len(all)-1]
if visibleLen(last) >= width {
last = clipRunes(last, width-1) + "…"
} else {
last = last + "…"
}
all[len(all)-1] = last
}
for i, l := range all {
out[i] = l
}
return out
}
// wrapToastWords is a small word-wrapper sized for toast bodies:
// greedy, breaks overlong words on rune boundaries, drops collapsing
// whitespace via strings.Fields.
func wrapToastWords(text string, width int) []string {
var lines []string
var cur string
flush := func() {
if cur != "" {
lines = append(lines, cur)
cur = ""
}
}
for _, word := range strings.Fields(text) {
for visibleLen(word) > width {
flush()
head := clipRunes(word, width)
lines = append(lines, head)
word = word[len(head):]
}
if word == "" {
continue
}
if cur == "" {
cur = word
continue
}
if visibleLen(cur)+1+visibleLen(word) <= width {
cur += " " + word
continue
}
flush()
cur = word
}
flush()
return lines
}
func toastIcon(kind toastKind) string {
switch kind {
case toastError:
return styleError + "✗ " + styleReset
case toastAttention:
return styleAccent + "! " + styleReset
default:
return styleHint + "• " + styleReset
}
}