feat(ledger): leios genesis struct and readers (#1199)

Signed-off-by: Chris Gianelloni <[email protected]>

Author: wolf31o2

ledger/leios/genesis.go

@@ -0,0 +1,55 @@
+// Copyright 2025 Blink Labs Software
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package leios
+
+import (
+	"encoding/json"
+	"io"
+	"os"
+)
+
+type LeiosGenesis struct {
+	HeaderDiffusionPeriod           uint  `json:"headerDiffusionPeriod"`
+	VotingPeriod                    uint  `json:"votingPeriod"`
+	DiffusionPeriod                 uint  `json:"diffusionPeriod"`
+	RankingBlockMaxSize             uint  `json:"rankingBlockMaxSize"`
+	EndorserBlockReferenceTxMaxSize uint  `json:"endorserBlockRefTxMaxSize"`
+	EndorserBlockMaxSize            uint  `json:"endorserBlockMaxSize"`
+	MeanCommitteeSize               uint  `json:"meanCommitteeSize"`
+	QuorumSize                      uint  `json:"quorumSize"`
+	MaxExStepPerEndorserBlock       int64 `json:"maxExStepPerEndorserBlock"`
+	MaxExMemPerEndorserBlock        int64 `json:"maxExMemPerEndorserBlock"`
+	MaxExStepPerTransaction         int64 `json:"maxExStepPerTransaction"`
+	MaxExMemPerTransaction          int64 `json:"maxExMemPerTransaction"`
+}
+
+func NewLeiosGenesisFromReader(r io.Reader) (LeiosGenesis, error) {
+	var ret LeiosGenesis
+	dec := json.NewDecoder(r)
+	dec.DisallowUnknownFields()
+	if err := dec.Decode(&ret); err != nil {
+		return ret, err
+	}
+	return ret, nil
+}
+
+func NewLeiosGenesisFromFile(path string) (LeiosGenesis, error) {
+	f, err := os.Open(path)
+	if err != nil {
+		return LeiosGenesis{}, err
+	}
+	defer f.Close()
+	return NewLeiosGenesisFromReader(f)
+}