package chain

import (
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"github.com/tcs-iptv/tcs/internal/model"
)

// RunClientConformance 是 chain.Client 的契约测试套件，校验任意实现都满足同一组
// 不可变业务规则（权限/1:1强绑定/防换壳/状态机/集级粒度）。
//
// 各实现（MemoryChain / PersistentChain / ChainMakerClient）复用本套件，
// 保证「换实现不换行为」，这是平滑替换真实链的安全保障。
//
// newClient 必须返回一个干净（空状态）的 Client 实例。
func RunClientConformance(t *testing.T, newClient func(t *testing.T) Client) {
	// 构造一条标准发码请求（集级 3 集）。
	issueReq := func(ma, ctid, fh string) IssueRequest {
		return IssueRequest{
			MACode: ma, ContentTwinID: ctid, MerkleRoot: "mr-" + fh, FileHash: fh,
			PerceptualHash: "ph-" + fh,
			Episodes: []model.EpisodeHash{
				{Episode: 1, FileSHA256: fh + "-E1"},
				{Episode: 2, FileSHA256: fh + "-E2"},
				{Episode: 3, FileSHA256: fh + "-E3"},
			},
			Content: model.Content{Title: "契约测试剧", EpisodeCount: 3, MAType: "WD", Issuer: "测试局"},
		}
	}
	const ma = "MA.156.8531.6101/WD/20260000001"
	const ctid = "ctid-conf-001"
	const fh = "fh-conf-001"

	t.Run("IssueMA_仅监管可发码", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleCP, issueReq(ma, ctid, fh))
		assert.ErrorIs(t, err, ErrPermissionDenied)
	})

	t.Run("IssueMA_成功并可查询", func(t *testing.T) {
		c := newClient(t)
		tx, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		assert.NotEmpty(t, tx)
		got, err := c.QueryContent(ma)
		require.NoError(t, err)
		assert.Equal(t, "契约测试剧", got.Title)
		assert.Equal(t, model.StatusApproved, got.Status)
	})

	t.Run("IssueMA_不可重复签发", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		_, err = c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		assert.ErrorIs(t, err, ErrMAAlreadyIssued)
	})

	t.Run("防换壳_同哈希不可绑不同MA", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		_, exists := c.HashExists(fh)
		assert.True(t, exists)
		_, err = c.IssueMA(RoleRegulator, issueReq("MA.156.8531.6101/WD/20260000002", "ctid-x", fh))
		assert.ErrorIs(t, err, ErrHashExists)
	})

	t.Run("VerifyHash_匹配与不匹配", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		r, err := c.VerifyHash(ma, fh)
		require.NoError(t, err)
		assert.True(t, r.Match)
		r2, _ := c.VerifyHash(ma, "tampered")
		assert.False(t, r2.Match)
	})

	t.Run("集级验真与列出", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		r, err := c.VerifyEpisodeHash(ma, 2, fh+"-E2")
		require.NoError(t, err)
		assert.True(t, r.Match)
		eps, err := c.ListEpisodes(ma)
		require.NoError(t, err)
		assert.Len(t, eps, 3)
	})

	t.Run("映射注册需先发码且可查", func(t *testing.T) {
		c := newClient(t)
		// 未发码不可注册映射
		_, err := c.RegisterMapping(RoleCP, model.Mapping{ContentTwinID: "ctid-none", Party: model.PartyCP, PartyID: "X"})
		assert.ErrorIs(t, err, ErrMANotIssued)
		// 发码后可注册并查询
		_, err = c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		_, err = c.RegisterMapping(RoleOperator, model.Mapping{
			ContentTwinID: ctid, Party: model.PartyOperator, PartyID: "OP-1", CDNEndpoint: "cdn://x",
		})
		require.NoError(t, err)
		mr, err := c.QueryMappings(ma)
		require.NoError(t, err)
		assert.GreaterOrEqual(t, len(mr.Mappings), 1)
		assert.Contains(t, mr.CDNEndpoints, "cdn://x")
	})

	t.Run("下架_仅监管且状态变更", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		_, err = c.Revoke(RoleCP, ma, "x")
		assert.ErrorIs(t, err, ErrPermissionDenied)
		_, err = c.Revoke(RoleRegulator, ma, "违规")
		require.NoError(t, err)
		got, _ := c.QueryContent(ma)
		assert.Equal(t, model.StatusRevoked, got.Status)
	})

	t.Run("集级下架与恢复", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		require.NoError(t, c.RevokeEpisode(RoleRegulator, ma, 2, "违规集"))
		eps, _ := c.ListEpisodes(ma)
		for _, e := range eps {
			if e.Episode == 2 {
				assert.True(t, e.Revoked)
			}
		}
		require.NoError(t, c.RestoreEpisode(RoleRegulator, ma, 2))
		eps, _ = c.ListEpisodes(ma)
		for _, e := range eps {
			if e.Episode == 2 {
				assert.False(t, e.Revoked)
			}
		}
	})

	t.Run("状态流转与按状态列举", func(t *testing.T) {
		c := newClient(t)
		_, err := c.IssueMA(RoleRegulator, issueReq(ma, ctid, fh))
		require.NoError(t, err)
		require.NoError(t, c.SetContentStatus(ma, model.StatusPublished))
		pub, err := c.ListContents(model.StatusPublished)
		require.NoError(t, err)
		assert.Len(t, pub, 1)
	})
}

// TestMemoryChain_Conformance 让内存实现跑契约套件（始终运行）。
func TestMemoryChain_Conformance(t *testing.T) {
	RunClientConformance(t, func(t *testing.T) Client {
		return NewMemoryChain()
	})
}