From 241ec1d194485f76c23cdedfba6e348055961ac0 Mon Sep 17 00:00:00 2001
From: Emanuel Pargov <bamzedev@gmail.com>
Date: Fri, 26 Jul 2024 12:02:19 +0300
Subject: [PATCH 1/2] Add ticket structs (#18)

---
 internal/block/block.go  |  8 ++++++++
 internal/block/ticket.go | 20 ++++++++++++++++++++
 2 files changed, 28 insertions(+)
 create mode 100644 internal/block/ticket.go

diff --git a/internal/block/block.go b/internal/block/block.go
index 9520e22..a7eb69a 100644
--- a/internal/block/block.go
+++ b/internal/block/block.go
@@ -1,4 +1,12 @@
 package block
 
+// Block represents the main block structure
 type Block struct {
+	Header    *Header
+	Extrinsic *Extrinsic
+}
+
+// Extrinsic represents the block extrinsic data
+type Extrinsic struct {
+	ET []*TicketProof
 }
diff --git a/internal/block/ticket.go b/internal/block/ticket.go
new file mode 100644
index 0000000..5a94531
--- /dev/null
+++ b/internal/block/ticket.go
@@ -0,0 +1,20 @@
+package block
+
+import "github.com/eigerco/strawberry/internal/crypto"
+
+const (
+	maxTicketsPerBlock = 16  // `K` in the paper. The maximum number of tickets which may be submitted in a single extrinsic.
+	ticketProofSize    = 784 // Size of F̄[]γz⟨XT ⌢ η′2 r⟩
+)
+
+// Ticket represents a single ticket (C in equation 50)
+type Ticket struct {
+	Identifier crypto.Hash // y ∈ H 32bytes hash
+	EntryIndex uint8       // r ∈ Nn (0, 1)
+}
+
+// TicketProof represents a proof of a valid ticket
+type TicketProof struct {
+	EntryIndex uint8                 // r ∈ Nn (0, 1)
+	Proof      [ticketProofSize]byte // RingVRF proof
+}

From 11856c3d9a28052b1de73683efc2bdd9002cf207 Mon Sep 17 00:00:00 2001
From: Daniel Vladco <vladcodaniel@gmail.com>
Date: Mon, 29 Jul 2024 12:57:46 +0300
Subject: [PATCH 2/2] Add header fields (#16)

feat: add header fields
---
 internal/block/header.go        | 25 +++++++++++++++++++++++++
 internal/crypto/bandersnatch.go |  4 ++++
 2 files changed, 29 insertions(+)
 create mode 100644 internal/crypto/bandersnatch.go

diff --git a/internal/block/header.go b/internal/block/header.go
index 50bb32b..aa14fe8 100644
--- a/internal/block/header.go
+++ b/internal/block/header.go
@@ -1,4 +1,29 @@
 package block
 
+import (
+	"github.com/eigerco/strawberry/internal/crypto"
+	"github.com/eigerco/strawberry/internal/time"
+)
+
+const NumberOfValidators uint16 = 1023
+
+// Header as defined in the section 5 in the paper
 type Header struct {
+	ParentHash           crypto.Hash                     // Hp
+	PriorStateRoot       crypto.Hash                     // Hr
+	ExtrinsicHash        crypto.Hash                     // Hx
+	TimeSlotIndex        time.Timeslot                   // Ht
+	EpochMarker          *EpochMarker                    // He
+	WinningTicketsMarker [time.TimeslotsPerEpoch]*Ticket // Hw
+	JudgementsMarkers    []crypto.Hash                   // Hj
+	PublicKeyIndex       uint16                          // Hk
+	VRFSignature         crypto.BandersnatchSignature    // Hv
+	BlockSealSignature   crypto.BandersnatchSignature    // Hs
+}
+
+// EpochMarker consists of epoch randomness and a sequence of
+// Bandersnatch keys defining the Bandersnatch validator keys (kb) beginning in the next epoch.
+type EpochMarker struct {
+	Keys    [NumberOfValidators]crypto.BandersnatchPublicKey
+	Entropy crypto.Hash
 }
diff --git a/internal/crypto/bandersnatch.go b/internal/crypto/bandersnatch.go
new file mode 100644
index 0000000..b70e5db
--- /dev/null
+++ b/internal/crypto/bandersnatch.go
@@ -0,0 +1,4 @@
+package crypto
+
+type BandersnatchPublicKey [BandersnatchSize]byte
+type BandersnatchSignature [96]byte