From fcf01fcbf66fc18e4160d002219dd1c0c2fa264d Mon Sep 17 00:00:00 2001
From: fiatjaf <fiatjaf@gmail.com>
Date: Fri, 7 Feb 2025 18:02:34 -0300
Subject: [PATCH] pool's PaginatorWithTimeout() helper.

---
 paginator.go | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 paginator.go

diff --git a/paginator.go b/paginator.go
new file mode 100644
index 0000000..ea5e57d
--- /dev/null
+++ b/paginator.go
@@ -0,0 +1,68 @@
+package nostr
+
+import (
+	"context"
+	"math"
+	"slices"
+	"time"
+)
+
+func (pool *SimplePool) PaginatorWithInterval(
+	interval time.Duration,
+) func(ctx context.Context, urls []string, filter Filter, opts ...SubscriptionOption) chan RelayEvent {
+	return func(ctx context.Context, urls []string, filter Filter, opts ...SubscriptionOption) chan RelayEvent {
+		nextUntil := Now()
+		if filter.Until != nil {
+			nextUntil = *filter.Until
+		}
+
+		globalLimit := uint64(filter.Limit)
+		if globalLimit == 0 && !filter.LimitZero {
+			globalLimit = math.MaxUint64
+		}
+		var globalCount uint64 = 0
+		globalCh := make(chan RelayEvent)
+
+		repeatedCache := make([]string, 0, 300)
+		nextRepeatedCache := make([]string, 0, 300)
+
+		go func() {
+			defer close(globalCh)
+
+			for {
+				filter.Until = &nextUntil
+				time.Sleep(interval)
+
+				keepGoing := false
+				for evt := range pool.SubManyEose(ctx, urls, Filters{filter}, opts...) {
+					if slices.Contains(repeatedCache, evt.ID) {
+						continue
+					}
+
+					keepGoing = true // if we get one that isn't repeated, then keep trying to get more
+					nextRepeatedCache = append(nextRepeatedCache, evt.ID)
+
+					globalCh <- evt
+
+					globalCount++
+					if globalCount >= globalLimit {
+						return
+					}
+
+					if evt.CreatedAt < *filter.Until {
+						nextUntil = evt.CreatedAt
+					}
+				}
+
+				if !keepGoing {
+					return
+				}
+
+				repeatedCache = nextRepeatedCache
+				nextRepeatedCache = nextRepeatedCache[:0]
+			}
+		}()
+
+		return globalCh
+	}
+}