package hash

import (
	"testing"

	"github.com/nspcc-dev/neo-go/pkg/util"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func testComputeMerkleTree(t *testing.T, hexHashes []string, result string) {
	hashes := make([]util.Uint256, len(hexHashes))
	for i, str := range hexHashes {
		hash, err := util.Uint256DecodeStringLE(str)
		require.NoError(t, err)
		hashes[i] = hash
	}

	merkle, err := NewMerkleTree(hashes)
	require.NoError(t, err)
	optimized := CalcMerkleRoot(hashes)
	assert.Equal(t, result, optimized.StringLE())
	assert.Equal(t, result, merkle.Root().StringLE())
	assert.Equal(t, true, merkle.root.IsRoot())
	assert.Equal(t, false, merkle.root.IsLeaf())
	leaf := merkle.root
	for leaf.leftChild != nil || leaf.rightChild != nil {
		if leaf.leftChild != nil {
			leaf = leaf.leftChild
			continue
		}
		leaf = leaf.rightChild
	}
	assert.Equal(t, true, leaf.IsLeaf())
	assert.Equal(t, false, leaf.IsRoot())
}

func TestComputeMerkleTree1(t *testing.T) {
	// Mainnet block #0
	rawHashes := []string{
		"fb5bd72b2d6792d75dc2f1084ffa9e9f70ca85543c717a6b13d9959b452a57d6",
		"c56f33fc6ecfcd0c225c4ab356fee59390af8560be0e930faebe74a6daff7c9b",
		"602c79718b16e442de58778e148d0b1084e3b2dffd5de6b7b16cee7969282de7",
		"3631f66024ca6f5b033d7e0809eb993443374830025af904fb51b0334f127cda",
	}
	res := "803ff4abe3ea6533bcc0be574efa02f83ae8fdc651c879056b0d9be336c01bf4"
	testComputeMerkleTree(t, rawHashes, res)
}

func TestComputeMerkleTree2(t *testing.T) {
	// Mainnet block #4635525
	rawHashes := []string{
		"c832ef573136eae2c57a35989d3fb9b3a135d08ffa0faa49d8766f7c1a92ca0f",
		"b8606dfeb126a5963d6674f8dbfb786db7f6c27800167c3eef56ff7110ff0ffc",
		"498a5d58179002dd9db7b23df657ecf7e1b2e8218bd48dda035e5accc664830a",
		"5c350282b448c139adb1f5e3fba0e9326476a38c01ea88876ebc4a882c472d42",
		"cea31cc85e7310183561d4f420026984ba48354516f9274c44b52c7f9a5c6107",
		"744f985dd5ad6f4ad6376376b48552abf7755b2ebc5c6271950714f848d1cc3a",
		"02c5fc225b6ead91f73a7b3ebb19bb30a113baea60f439b654c2811d630a2c48",
		"2b3478e0fa91db3a309caeb4d9739f38233c1c189d6fa7e159e24afce9fae082",
		"4d50693cee3ac2c976c092620834d4da264583cf15a1d11dd65d0e94861d49e0",
		"5f179efae999f8f8086269cedd1fbfaf6e90aadf5369a12737db0fff5905b12e",
		"6ef2237b6c8683f626269027050c45cc4be89042ee99e4e89bfd9d9fbd24da19",
		"6fd5154af55b4a1e4a1a5272e33238b2a2da12a30fa06af4f740d207e54ed495",
	}
	res := "42489ad8043a834149cd8e406c90c61411a05a0ca9f8e921b456a00b5d5988d7"
	testComputeMerkleTree(t, rawHashes, res)
}

func TestComputeMerkleTree3(t *testing.T) {
	// Mainnet block #2097152
	rawHashes := []string{
		"a7ff2c6aa08d4b979d5f7605aec5a1783c9207c738b5852ed5ff17b37ada649d",
		"34fd42c1f47aa306ad2fd0fc04437fd5c828a25b3de59e73b18157253094a8da",
		"36458dffd678d9f75ed9f2a28beb58bf1ad739f8899469b8641b0ddea22fcf5d",
		"3e8144abe2edda263593f24defd4557d403efa1b4fa839409ac217d6f8a87d3a",
		"a1d2cf73841fefcd21ca9986c664518d2af61edcfe3a97b30b3cc58fab4e61f6",
		"c1e868aef0e8fd76b95a18e155b1fa65f30d0a4887bc953411553728664725bc",
		"52d2fda0fe0fd586063d801c5ba77ca123a790d7e4dae34c53398feab36da721",
		"fdf8d4610cb2de35ab4c18d38357b86c52966d149c8975906170dc513cc26345",
		"35a26a11ef65d8f7a2424f7ce5915aa1d8bf3449018516003799767c2696197e",
		"c9d251abfc20a0d6eeac2d5a93b77a6a0632a679a07decea2c809aead89bb503",
		"d92c72873f2929c621ec06433da3053db25ee396b70c83d53abd40801823f66c",
	}
	res := "09c2dbc88810c350a2e7ace56bb1b371b2a2b5c4744e7a303adace9a2c2bbf6d"
	testComputeMerkleTree(t, rawHashes, res)
}

func TestNewMerkleTreeFailWithoutHashes(t *testing.T) {
	var hashes []util.Uint256
	_, err := NewMerkleTree(hashes)
	require.Error(t, err)
	hashes = make([]util.Uint256, 0)
	_, err = NewMerkleTree(hashes)
	require.Error(t, err)
}

func TestBuildMerkleTreeWithoutNodes(t *testing.T) {
	var leaves []*MerkleTreeNode
	require.Panics(t, func() { buildMerkleTree(leaves) })
	leaves = make([]*MerkleTreeNode, 0)
	require.Panics(t, func() { buildMerkleTree(leaves) })
}