package worker

import (
	"context"
	"testing"
	"time"

	"proxy-pool/internal/controlplane/snapshotwire"
)

func TestInitialSnapshotSourceIssuesNextFullSnapshot(t *testing.T) {
	now := time.Date(2026, 7, 31, 12, 0, 0, 0, time.UTC)
	source, err := NewInitialSnapshotSource(epochReaderStub{epoch: 9}, time.Minute, func() time.Time { return now })
	if err != nil {
		t.Fatalf("NewInitialSnapshotSource(): %v", err)
	}
	updates, err := source.Watch(context.Background(), SnapshotWatchRequest{
		WorkerID: "worker-a", SessionID: "session-a", LastAppliedVersion: 4,
	})
	if err != nil {
		t.Fatalf("Watch(): %v", err)
	}
	full := <-updates
	if full.GetVersion() != 5 || full.GetOwnershipEpoch() != 9 || !full.GetValidUntil().AsTime().Equal(now.Add(time.Minute)) {
		t.Fatalf("snapshot = %+v", full)
	}
	checksum, err := snapshotwire.Checksum(full)
	if err != nil || string(checksum[:]) != string(full.GetChecksum()) {
		t.Fatalf("snapshot checksum = %x, %v; want %x", full.GetChecksum(), err, checksum)
	}
}

type epochReaderStub struct {
	epoch uint64
	err   error
}

func (reader epochReaderStub) CurrentOwnershipEpoch(context.Context) (uint64, error) {
	return reader.epoch, reader.err
}