package overlay
import (
"io"
"sync"
)
// OutputGate wraps a writer and can freeze/unfreeze output.
// When frozen, all writes are discarded. When unfrozen, writes pass through.
// This is used to prevent PTY output from corrupting the overlay menu.
type OutputGate struct {
out io.Writer
mu sync.Mutex
frozen bool
onFreeze func()
onUnfreeze func()
}
// NewOutputGate creates a new OutputGate.
func NewOutputGate(out io.Writer) *OutputGate {
return &OutputGate{
out: out,
}
}
// SetCallbacks sets the freeze/unfreeze callbacks.
func (og *OutputGate) SetCallbacks(onFreeze, onUnfreeze func()) {
og.mu.Lock()
defer og.mu.Unlock()
og.onFreeze = onFreeze
og.onUnfreeze = onUnfreeze
}
// Write writes to the underlying writer if not frozen.
// When frozen, writes are discarded but return success.
func (og *OutputGate) Write(p []byte) (n int, err error) {
og.mu.Lock()
defer og.mu.Unlock()
if og.frozen {
// Discard but report success
return len(p), nil
}
return og.out.Write(p)
}
// Freeze stops writing to the underlying writer (discards writes).
// Calls onFreeze callback if set and not already frozen.
func (og *OutputGate) Freeze() {
og.mu.Lock()
defer og.mu.Unlock()
if og.frozen {
return // Already frozen, don't call callback again
}
og.frozen = true
if og.onFreeze != nil {
og.onFreeze()
}
}
// Unfreeze resumes writing to the underlying writer.
// Calls onUnfreeze callback if set and was frozen.
func (og *OutputGate) Unfreeze() {
og.mu.Lock()
defer og.mu.Unlock()
if !og.frozen {
return // Already unfrozen, don't call callback again
}
og.frozen = false
if og.onUnfreeze != nil {
og.onUnfreeze()
}
}
// IsFrozen returns whether the gate is currently frozen.
func (og *OutputGate) IsFrozen() bool {
og.mu.Lock()
defer og.mu.Unlock()
return og.frozen
}
