neko/internal/webrtc/cursor/image.go
2021-02-28 18:52:37 +01:00

132 lines
2.6 KiB
Go

package cursor
import (
"reflect"
"sync"
"github.com/rs/zerolog"
"github.com/rs/zerolog/log"
"demodesk/neko/internal/types"
"demodesk/neko/internal/utils"
)
func NewImage(desktop types.DesktopManager) *ImageCtx {
return &ImageCtx{
logger: log.With().Str("module", "cursor-image").Logger(),
desktop: desktop,
listeners: map[uintptr]*func(entry *ImageEntry){},
cache: map[uint64]*ImageEntry{},
}
}
type ImageCtx struct {
logger zerolog.Logger
desktop types.DesktopManager
emitMu sync.Mutex
listeners map[uintptr]*func(entry *ImageEntry)
cacheMu sync.Mutex
cache map[uint64]*ImageEntry
current *ImageEntry
}
type ImageEntry struct {
Cursor *types.CursorImage
Image []byte
}
func (manager *ImageCtx) Start() {
manager.desktop.OnCursorChanged(func(serial uint64) {
entry, err := manager.GetCached(serial)
if err != nil {
manager.logger.Warn().Err(err).Msg("failed to get cursor image")
return
}
for _, emit := range manager.listeners {
(*emit)(entry)
}
})
}
func (manager *ImageCtx) Shutdown() {
manager.logger.Info().Msgf("shutting down")
manager.emitMu.Lock()
for key := range manager.listeners {
delete(manager.listeners, key)
}
manager.emitMu.Unlock()
}
func (manager *ImageCtx) GetCached(serial uint64) (*ImageEntry, error) {
// zero means no serial available
if serial == 0 {
return manager.fetchEntry()
}
manager.cacheMu.Lock()
entry, ok := manager.cache[serial]
manager.cacheMu.Unlock()
if ok {
return entry, nil
}
entry, err := manager.fetchEntry()
if err != nil {
return nil, err
}
manager.cacheMu.Lock()
manager.cache[serial] = entry
manager.cacheMu.Unlock()
return entry, nil
}
func (manager *ImageCtx) Get() (*ImageEntry, error) {
if manager.current != nil {
return manager.current, nil
}
return manager.fetchEntry()
}
func (manager *ImageCtx) AddListener(listener *func(entry *ImageEntry)) {
manager.emitMu.Lock()
defer manager.emitMu.Unlock()
if listener != nil {
ptr := reflect.ValueOf(listener).Pointer()
manager.listeners[ptr] = listener
}
}
func (manager *ImageCtx) RemoveListener(listener *func(entry *ImageEntry)) {
manager.emitMu.Lock()
defer manager.emitMu.Unlock()
if listener != nil {
ptr := reflect.ValueOf(listener).Pointer()
delete(manager.listeners, ptr)
}
}
func (manager *ImageCtx) fetchEntry() (*ImageEntry, error) {
cur := manager.desktop.GetCursorImage()
img, err := utils.CreatePNGImage(cur.Image)
if err != nil {
return nil, err
}
entry := &ImageEntry{
Cursor: cur,
Image: img,
}
manager.current = entry
return entry, nil
}