// Customizable hash function used for tree generation.
HashFunc TypeHashFunc
// Number of goroutines run in parallel.
// If RunInParallel is true and NumRoutine is set to 0, use number of CPU as the number of goroutines.
NumRoutines int
// Mode of the Merkle Tree generation.
Mode TypeConfigMode
// If RunInParallel is true, the generation runs in parallel, otherwise runs without parallelization.
// This increase the performance for the calculation of large number of data blocks, e.g. over 10,000 blocks.
RunInParallel bool
// SortSiblingPairs is the parameter for OpenZeppelin compatibility.
// If set to `true`, the hashing sibling pairs are sorted.
SortSiblingPairs bool
// If true, the leaf nodes are NOT hashed before being added to the Merkle Tree.
DisableLeafHashing bool

func myHashFunc(data []byte) ([]byte, error) {
    sha256Func := sha256.New()
    sha256Func.Write(data)
    return sha256Func.Sum(nil), nil
}

package main

import (
    "crypto/rand"
    "fmt"

    mt "github.com/txaty/go-merkletree"
)

// first define a data structure with Serialize method to be used as data block
type testData struct {
    data []byte
}

func (t *testData) Serialize() ([]byte, error) {
    return t.data, nil
}

// generate dummy data blocks
func generateRandBlocks(size int) (blocks []mt.DataBlock) {
    for i := 0; i < size; i++ {
        block := &testData{
            data: make([]byte, 100),
        }
        _, err := rand.Read(block.data)
        handleError(err)
        blocks = append(blocks, block)
    }
    return
}

func main() {
    blocks := generateRandBlocks(10)
    // the first argument is config, if it is nil, then default config is adopted
    tree, err := mt.New(nil, blocks)
    handleError(err)
    // get proofs
    proofs := tree.Proofs
    // verify the proofs
    for i := 0; i < len(proofs); i++ {
        ok, err := tree.Verify(blocks[i], proofs[i])
        handleError(err)
        fmt.Println(ok)
    }
    // or you can also verify the proofs without the tree but with Merkle root
    // obtain the Merkle root
    rootHash := tree.Root
    for i := 0; i < len(blocks); i++ {
        // if hashFunc is nil, use SHA256 by default
        ok, err := mt.Verify(blocks[i], proofs[i], rootHash, nil)
        handleError(err)
        fmt.Println(ok)
    }
}

func handleError(err error) {
    if err != nil {
        panic(err)
    }
}

blocks := generateRandBlocks(10)

// create a Merkle Tree config and set mode to tree building
config := &mt.Config{
    Mode: ModeTreeBuild,
}
tree, err := mt.New(config, blocks)
handleError(err)
// get the proof for a specific data block
// method GenerateProof is only available when ModeTreeBuild or ModeProofGenAndTreeBuild
proof0, err := tree.GenerateProof(blocks[0])
handleError(err)
proof3, err := tree.GenerateProof(blocks[3])
handleError(err)

blocks := generateRandBlocks(10)

// create a Merkle Tree config and set parallel run parameters
config := &mt.Config{
    RunInParallel: true,
    NumRoutines: 4,
}
tree, err := mt.New(config, blocks)
handleError(err)