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package pds
import (
"context"
"sync"
"github.com/johnandersen777/socialweb-computer-kcp/internal/atproto/repo"
)
type Sequencer struct {
mu sync.Mutex
subs map[chan *repo.CommitEvent]struct{}
}
func NewSequencer() *Sequencer {
return &Sequencer{subs: make(map[chan *repo.CommitEvent]struct{})}
}
func (s *Sequencer) OnCommit(_ context.Context, ev *repo.CommitEvent) error {
if ev == nil {
return nil
}
s.mu.Lock()
defer s.mu.Unlock()
for ch := range s.subs {
select {
case ch <- ev:
default:
delete(s.subs, ch)
close(ch)
}
}
return nil
}
func (s *Sequencer) Subscribe() (<-chan *repo.CommitEvent, func()) {
ch := make(chan *repo.CommitEvent, 512)
s.mu.Lock()
s.subs[ch] = struct{}{}
s.mu.Unlock()
cancel := func() {
s.mu.Lock()
defer s.mu.Unlock()
if _, ok := s.subs[ch]; ok {
delete(s.subs, ch)
close(ch)
}
}
return ch, cancel
}
