init: AIGC-Hub/AVCC 方案文档 + TCS-IPTV 内容可信锁定系统 MVP

- 方案文档: AVCC 体系建设、IPTV TCS 需求(0-req)/PRD(1-prd)/任务(2-task)/二三四期任务
- tcs-iptv: Go 后端(哈希SDK/MA码生成/可信数据空间mock/业务编排/HTTP API+HMAC鉴权)
- web-console: React+AntD 监管大屏(角色工作台/全流程演示/监管片库)
- 一剧一码+集级哈希, 集级下架/恢复, 全栈测试通过

tcs-iptv/internal/hash/hash_test.go

@@ -0,0 +1,151 @@
+package hash
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func writeTempFile(t *testing.T, data []byte) string {
+	t.Helper()
+	dir := t.TempDir()
+	p := filepath.Join(dir, "master.bin")
+	require.NoError(t, os.WriteFile(p, data, 0o644))
+	return p
+}
+
+func TestSHA256Hex_Deterministic(t *testing.T) {
+	a := SHA256Hex([]byte("hello"))
+	b := SHA256Hex([]byte("hello"))
+	assert.Equal(t, a, b)
+	// 已知向量
+	assert.Equal(t, "2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824", a)
+}
+
+func TestFileSHA256_MatchesBytes(t *testing.T) {
+	data := []byte("the quick brown fox")
+	p := writeTempFile(t, data)
+	got, err := FileSHA256(p)
+	require.NoError(t, err)
+	assert.Equal(t, SHA256Hex(data), got)
+}
+
+func TestSegmentHashes_SmallSegments(t *testing.T) {
+	// 25 字节，分段 10 → 3 段（10/10/5）
+	data := []byte("0123456789ABCDEFGHIJ12345")
+	p := writeTempFile(t, data)
+	segs, err := SegmentHashes(p, 10)
+	require.NoError(t, err)
+	require.Len(t, segs, 3)
+	assert.Equal(t, SHA256Hex(data[0:10]), segs[0])
+	assert.Equal(t, SHA256Hex(data[10:20]), segs[1])
+	assert.Equal(t, SHA256Hex(data[20:25]), segs[2])
+}
+
+func TestMerkleTree_RootStableAndChangesOnEdit(t *testing.T) {
+	leaves := []string{
+		SHA256Hex([]byte("ep1")),
+		SHA256Hex([]byte("ep2")),
+		SHA256Hex([]byte("ep3")),
+		SHA256Hex([]byte("ep4")),
+	}
+	root1 := BuildMerkleTree(leaves).Root()
+	root2 := BuildMerkleTree(leaves).Root()
+	assert.Equal(t, root1, root2, "同样叶子根应一致")
+	assert.NotEmpty(t, root1)
+
+	// 改第3集 → 根变化
+	edited := append([]string(nil), leaves...)
+	edited[2] = SHA256Hex([]byte("ep3-tampered"))
+	root3 := BuildMerkleTree(edited).Root()
+	assert.NotEqual(t, root1, root3, "篡改任一集，根必变")
+}
+
+func TestMerkleTree_OddLeaves(t *testing.T) {
+	leaves := []string{
+		SHA256Hex([]byte("a")),
+		SHA256Hex([]byte("b")),
+		SHA256Hex([]byte("c")),
+	}
+	mt := BuildMerkleTree(leaves)
+	assert.NotEmpty(t, mt.Root())
+}
+
+func TestLocateChangedLeaves(t *testing.T) {
+	old := []string{"h1", "h2", "h3", "h4"}
+	neu := []string{"h1", "x2", "h3", "x4"}
+	changed := LocateChangedLeaves(old, neu)
+	assert.Equal(t, []int{1, 3}, changed, "应定位到第2集和第4集被改")
+}
+
+func TestComputeFile_FullPackage(t *testing.T) {
+	data := make([]byte, 25*1024) // 25KB
+	for i := range data {
+		data[i] = byte(i % 251)
+	}
+	p := writeTempFile(t, data)
+
+	pkg, err := ComputeFile(p, Options{SegmentSize: 10 * 1024})
+	require.NoError(t, err)
+	require.NoError(t, pkg.Validate())
+	assert.Equal(t, int64(25*1024), pkg.FileSize)
+	assert.Len(t, pkg.SegmentHashes, 3)
+	assert.NotEmpty(t, pkg.MerkleRoot)
+	assert.Equal(t, SHA256Hex(data), pkg.FileSHA256)
+}
+
+func TestComputeFile_EmptyFileRejected(t *testing.T) {
+	p := writeTempFile(t, []byte{})
+	_, err := ComputeFile(p, Options{})
+	assert.ErrorIs(t, err, ErrEmptyInput)
+}
+
+func TestComputeFile_MissingFile(t *testing.T) {
+	_, err := ComputeFile("/no/such/file.bin", Options{})
+	assert.Error(t, err)
+}
+
+func TestHashPackage_ValidateMissingFields(t *testing.T) {
+	assert.Error(t, (&HashPackage{MerkleRoot: "x"}).Validate()) // 缺 file_sha256
+	assert.Error(t, (&HashPackage{FileSHA256: "x"}).Validate()) // 缺 merkle_root
+	assert.NoError(t, (&HashPackage{FileSHA256: "a", MerkleRoot: "b"}).Validate())
+}
+
+func TestPerceptualHash_IdenticalAndDifferent(t *testing.T) {
+	// 全黑与全白图，aHash/dHash 应可区分
+	black := make([][]uint8, 16)
+	white := make([][]uint8, 16)
+	grad := make([][]uint8, 16)
+	for y := 0; y < 16; y++ {
+		black[y] = make([]uint8, 16)
+		white[y] = make([]uint8, 16)
+		grad[y] = make([]uint8, 16)
+		for x := 0; x < 16; x++ {
+			white[y][x] = 255
+			grad[y][x] = uint8(x * 16) // 水平渐变
+		}
+	}
+	imgBlack := newGrayTestImage(black)
+	imgWhite := newGrayTestImage(white)
+	imgGrad := newGrayTestImage(grad)
+
+	// 同一图的哈希稳定
+	assert.Equal(t, AHash(imgGrad), AHash(imgGrad))
+	assert.Equal(t, DHash(imgGrad), DHash(imgGrad))
+
+	// 渐变图的 dHash 应与纯色不同
+	assert.NotEqual(t, DHash(imgGrad), DHash(imgBlack))
+
+	// 汉明距离：渐变 vs 纯白 应 > 0
+	d, err := HammingDistance(DHash(imgGrad), DHash(imgWhite))
+	require.NoError(t, err)
+	assert.Greater(t, d, 0)
+}
+
+func TestHammingDistance_LengthMismatch(t *testing.T) {
+	_, err := HammingDistance("ffff", "ffffffff")
+	assert.Error(t, err)
+}