zot/internal/tui/terminal.go
2026-04-17 20:36:38 +02:00

101 lines
2.7 KiB
Go

package tui
import (
"io"
"os"
"time"
"golang.org/x/term"
)
// Terminal abstracts the real terminal for tests.
type Terminal interface {
io.Writer
// Size returns (cols, rows).
Size() (int, int)
// OnResize registers a callback invoked on SIGWINCH (best effort).
OnResize(func())
// EnterRaw puts the tty into raw mode. Returns a restore func.
EnterRaw() (restore func() error, err error)
// ReadByte reads one byte of input. Blocks.
ReadByte() (byte, error)
// PeekByteTimeout reads one byte of input but returns (0, false, nil)
// if no byte arrives within the timeout. Used to disambiguate bare
// Esc from the start of an escape sequence.
PeekByteTimeout(time.Duration) (byte, bool, error)
// SetNonblock sets stdin to non-blocking mode (used by paste handling).
// May be a no-op on some platforms.
SetNonblock(bool) error
}
// ProcTerm is a Terminal bound to the current process's tty.
type ProcTerm struct {
out *os.File
in *os.File
resizeCBs []func()
}
// NewProcTerm returns a Terminal bound to stdin/stdout.
func NewProcTerm() *ProcTerm {
return &ProcTerm{out: os.Stdout, in: os.Stdin}
}
func (p *ProcTerm) Write(b []byte) (int, error) { return p.out.Write(b) }
func (p *ProcTerm) Size() (int, int) {
w, h, err := term.GetSize(int(p.out.Fd()))
if err != nil || w <= 0 || h <= 0 {
return 80, 24
}
return w, h
}
func (p *ProcTerm) OnResize(fn func()) {
p.resizeCBs = append(p.resizeCBs, fn)
p.installResizeHandler()
}
func (p *ProcTerm) EnterRaw() (func() error, error) {
fd := int(p.in.Fd())
if !term.IsTerminal(fd) {
return func() error { return nil }, nil
}
st, err := term.MakeRaw(fd)
if err != nil {
return nil, err
}
return func() error { return term.Restore(fd, st) }, nil
}
func (p *ProcTerm) ReadByte() (byte, error) {
var b [1]byte
_, err := p.in.Read(b[:])
return b[0], err
}
// PeekByteTimeout uses a platform-specific non-blocking read to decide
// whether another byte is available within d. If not, returns (0, false, nil).
func (p *ProcTerm) PeekByteTimeout(d time.Duration) (byte, bool, error) {
return peekStdin(p.in, d)
}
// ---- terminal control sequences ----
// HideCursor, ShowCursor, ClearScreen, BracketedPasteOn/Off, etc.
const (
SeqHideCursor = "\x1b[?25l"
SeqShowCursor = "\x1b[?25h"
SeqClearScreen = "\x1b[2J\x1b[H"
SeqClearLine = "\x1b[2K"
SeqBracketedPasteOn = "\x1b[?2004h"
SeqBracketedPasteOff = "\x1b[?2004l"
SeqAltScreenOn = "\x1b[?1049h"
SeqAltScreenOff = "\x1b[?1049l"
SeqSynchronizedOn = "\x1b[?2026h"
SeqSynchronizedOff = "\x1b[?2026l"
)
// MoveTo moves the cursor to 1-indexed (row, col).
func MoveTo(row, col int) string {
return "\x1b[" + itoa(row) + ";" + itoa(col) + "H"
}