package model_test

import (
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"go.yandata.net/iod/iod/trustlog-sdk/api/model"
)

// TestSignVerifyDataConsistency 详细测试加签和验签的数据一致性.
func TestSignVerifyDataConsistency(t *testing.T) {
	t.Parallel()

	// 生成SM2密钥对
	keyPair, err := model.GenerateSM2KeyPair()
	require.NoError(t, err)

	// 序列化为DER格式
	privateKeyDER, err := model.MarshalSM2PrivateDER(keyPair.Private)
	require.NoError(t, err)

	publicKeyDER, err := model.MarshalSM2PublicDER(keyPair.Public)
	require.NoError(t, err)

	// 创建签名器
	signer := model.NewSM2Signer(privateKeyDER, publicKeyDER)

	// 测试数据1
	testData1 := []byte("test data for signing")

	// 测试数据2（不同数据）
	testData2 := []byte("different test data")

	// 1. 对testData1签名
	signature1, err := signer.Sign(testData1)
	require.NoError(t, err)
	require.NotNil(t, signature1)

	// 2. 用testData1验证signature1 - 应该成功
	valid, err := signer.Verify(testData1, signature1)
	require.NoError(t, err)
	assert.True(t, valid, "使用相同数据验证应该成功")

	// 3. 用testData2验证signature1 - 应该失败
	valid, err = signer.Verify(testData2, signature1)
	require.Error(t, err, "使用不同数据验证应该失败")
	assert.Contains(t, err.Error(), "signature verification failed")
	assert.False(t, valid)

	// 4. 对testData2签名
	signature2, err := signer.Sign(testData2)
	require.NoError(t, err)
	require.NotNil(t, signature2)

	// 5. 用testData2验证signature2 - 应该成功
	valid, err = signer.Verify(testData2, signature2)
	require.NoError(t, err)
	assert.True(t, valid, "使用相同数据验证应该成功")

	// 6. 用testData1验证signature2 - 应该失败
	valid, err = signer.Verify(testData1, signature2)
	require.Error(t, err, "使用不同数据验证应该失败")
	assert.Contains(t, err.Error(), "signature verification failed")
	assert.False(t, valid)

	t.Logf("测试完成：签名和验证逻辑正常")
}

// TestEnvelopeBodyTampering 测试修改envelope body后验签应该失败.
func TestEnvelopeBodyTampering(t *testing.T) {
	t.Parallel()

	// 生成SM2密钥对
	keyPair, err := model.GenerateSM2KeyPair()
	require.NoError(t, err)

	// 序列化为DER格式
	privateKeyDER, err := model.MarshalSM2PrivateDER(keyPair.Private)
	require.NoError(t, err)

	publicKeyDER, err := model.MarshalSM2PublicDER(keyPair.Public)
	require.NoError(t, err)

	// 创建签名配置
	signConfig := model.NewSM2EnvelopeConfig(privateKeyDER, publicKeyDER)
	verifyConfig := model.NewSM2VerifyConfig(publicKeyDER)

	// 创建测试Operation
	op := &model.Operation{
		OpID:         "op-test-002",
		Timestamp:    time.Now(),
		OpSource:     model.OpSourceIRP,
		OpType:       model.OpTypeOCCreateHandle,
		DoPrefix:     "test",
		DoRepository: "repo",
		Doid:         "test/repo/456",
		ProducerID:   "producer-2",
		OpActor:      "actor-2",
	}

	err = op.CheckAndInit()
	require.NoError(t, err)

	// 1. 加签：序列化为Envelope
	envelopeData, err := model.MarshalOperation(op, signConfig)
	require.NoError(t, err)
	require.NotNil(t, envelopeData)

	// 2. 验签：验证原始Envelope - 应该成功
	verifiedEnv, err := model.VerifyEnvelopeWithConfig(envelopeData, verifyConfig)
	require.NoError(t, err)
	require.NotNil(t, verifiedEnv)

	// 3. 反序列化获取原始body
	originalEnv, err := model.UnmarshalEnvelope(envelopeData)
	require.NoError(t, err)
	originalBody := originalEnv.Body
	originalSignature := originalEnv.Signature

	t.Logf("原始body长度: %d", len(originalBody))
	t.Logf("原始签名长度: %d", len(originalSignature))

	// 4. 创建修改后的body（完全不同的数据）
	modifiedBody := []byte("completely different body content")
	require.NotEqual(t, originalBody, modifiedBody, "修改后的body应该不同")

	// 5. 创建修改后的envelope（使用原始签名但修改body）
	modifiedEnv := &model.Envelope{
		ProducerID: originalEnv.ProducerID,
		Signature:  originalSignature, // 使用原始签名
		Body:       modifiedBody,      // 使用修改后的body
	}
	modifiedData, err := model.MarshalEnvelope(modifiedEnv)
	require.NoError(t, err)

	// 6. 验签修改后的envelope - 应该失败
	_, err = model.VerifyEnvelopeWithConfig(modifiedData, verifyConfig)
	require.Error(t, err, "修改body后验签应该失败")
	assert.Contains(t, err.Error(), "signature verification failed")

	t.Logf("测试完成：修改body后验签正确失败")
}

// TestEnvelopeSignatureTampering 测试修改envelope signature后验签应该失败.
func TestEnvelopeSignatureTampering(t *testing.T) {
	t.Parallel()

	// 生成SM2密钥对
	keyPair, err := model.GenerateSM2KeyPair()
	require.NoError(t, err)

	// 序列化为DER格式
	privateKeyDER, err := model.MarshalSM2PrivateDER(keyPair.Private)
	require.NoError(t, err)

	publicKeyDER, err := model.MarshalSM2PublicDER(keyPair.Public)
	require.NoError(t, err)

	// 创建签名配置
	signConfig := model.NewSM2EnvelopeConfig(privateKeyDER, publicKeyDER)
	verifyConfig := model.NewSM2VerifyConfig(publicKeyDER)

	// 创建测试Operation
	op := &model.Operation{
		OpID:         "op-test-003",
		Timestamp:    time.Now(),
		OpSource:     model.OpSourceIRP,
		OpType:       model.OpTypeOCCreateHandle,
		DoPrefix:     "test",
		DoRepository: "repo",
		Doid:         "test/repo/789",
		ProducerID:   "producer-3",
		OpActor:      "actor-3",
	}

	err = op.CheckAndInit()
	require.NoError(t, err)

	// 1. 加签：序列化为Envelope
	envelopeData, err := model.MarshalOperation(op, signConfig)
	require.NoError(t, err)

	// 2. 反序列化获取原始signature
	originalEnv, err := model.UnmarshalEnvelope(envelopeData)
	require.NoError(t, err)
	originalSignature := originalEnv.Signature

	// 3. 创建修改后的signature（完全不同的数据）
	modifiedSignature := make([]byte, len(originalSignature))
	copy(modifiedSignature, originalSignature)
	// 修改最后一个字节
	if len(modifiedSignature) > 0 {
		modifiedSignature[len(modifiedSignature)-1] ^= 0xFF
	}
	require.NotEqual(t, originalSignature, modifiedSignature, "修改后的signature应该不同")

	// 4. 创建修改后的envelope（使用原始body但修改signature）
	modifiedEnv := &model.Envelope{
		ProducerID: originalEnv.ProducerID,
		Signature:  modifiedSignature, // 使用修改后的signature
		Body:       originalEnv.Body,  // 使用原始body
	}
	modifiedData, err := model.MarshalEnvelope(modifiedEnv)
	require.NoError(t, err)

	// 5. 验签修改后的envelope - 应该失败
	_, err = model.VerifyEnvelopeWithConfig(modifiedData, verifyConfig)
	require.Error(t, err, "修改signature后验签应该失败")
	assert.Contains(t, err.Error(), "signature verification failed")

	t.Logf("测试完成：修改signature后验签正确失败")
}