From 1a20032aa15d1b37910d20d611c5c500efe7d729 Mon Sep 17 00:00:00 2001
From: Javed Khan <tuxcanfly@gmail.com>
Date: Fri, 2 Feb 2024 14:35:19 -0800
Subject: [PATCH] celestia-da: account for padding shares

---
 celestia/celestia.go      | 12 +++++++++++-
 celestia/celestia_test.go |  3 +--
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/celestia/celestia.go b/celestia/celestia.go
index f66934d..4a031b7 100644
--- a/celestia/celestia.go
+++ b/celestia/celestia.go
@@ -19,6 +19,16 @@ import (
 	"github.com/rollkit/go-da"
 )
 
+const (
+	// DefaultMaxBytes is the maximum blob size accepted by celestia core
+	// ADR-13 claims worst case padding approaches 2 rows for a full data square:
+	// see: https://github.com/celestiaorg/celestia-app/blob/main/docs/architecture/adr-013-non-interactive-default-rules-for-zero-padding.md
+	// square size (64) * two rows = 128 shares
+	// 128 shares * 512 bytes per share = 65,536 bytes to account for padding
+	// 1,973,786 - 65,536 = 1,908,250 bytes
+	DefaultMaxBytes = 1908250
+)
+
 // CelestiaDA implements the celestia backend for the DA interface
 type CelestiaDA struct {
 	client    *rpc.Client
@@ -40,7 +50,7 @@ func NewCelestiaDA(client *rpc.Client, namespace share.Namespace, gasPrice float
 // MaxBlobSize returns the max blob size
 func (c *CelestiaDA) MaxBlobSize(ctx context.Context) (uint64, error) {
 	// TODO: pass-through query to node, app
-	return appconsts.DefaultMaxBytes, nil
+	return DefaultMaxBytes, nil
 }
 
 // Get returns Blob for each given ID, or an error.
diff --git a/celestia/celestia_test.go b/celestia/celestia_test.go
index 5b3de0f..0d04a8f 100644
--- a/celestia/celestia_test.go
+++ b/celestia/celestia_test.go
@@ -5,7 +5,6 @@ import (
 	"encoding/hex"
 	"testing"
 
-	"github.com/celestiaorg/celestia-app/pkg/appconsts"
 	rpc "github.com/celestiaorg/celestia-node/api/rpc/client"
 	"github.com/celestiaorg/celestia-node/share"
 	"github.com/celestiaorg/nmt"
@@ -58,7 +57,7 @@ func TestCelestiaDA(t *testing.T) {
 	t.Run("MaxBlobSize", func(t *testing.T) {
 		maxBlobSize, err := m.MaxBlobSize(ctx)
 		assert.NoError(t, err)
-		assert.Equal(t, uint64(appconsts.DefaultMaxBytes), maxBlobSize)
+		assert.Equal(t, uint64(DefaultMaxBytes), maxBlobSize)
 	})
 
 	t.Run("Get_empty", func(t *testing.T) {