// Converter Client 單元測試。
//
// 測試策略：
//   - 用 httptest.Server mock task-scheduler 的 4 個 endpoint
//   - 用 stub MCTokenClient（直接回 token / 注入錯誤），不耦合真實 mc_token_client 邏輯
//   - 用 atomic counter 驗 retry 行為（attempts 數對齊 conversion.md §9.1）
//   - 大 body streaming 用 io.LimitReader（不真的寫 100MB 進 RAM）
//
// 對應 task 規範必含 case：
//   - InitJob：Success / StreamingBody / ContentTypeHeader / Conflict409 / Validation400 / 5xx_NoRetry / AuthExpired
//   - GetJob：Success / NotFound / 5xx_RetryThenSuccess
//   - Promote：Success / BadGateway
//   - List：Success / Empty / 5xxRetry
//
// Phase 0.8 conversion (見 .autoflow/04-architecture/conversion.md §2.5 + §9.1)
package conversion

import (
	"context"
	"errors"
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"sync"
	"sync/atomic"
	"testing"
	"time"

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

// ==========================================================================
// stub MCTokenClient — 解耦真實 mc_token_client 邏輯
// ==========================================================================

// stubTokenClient 是 test 用的 fake MCTokenClient。
type stubTokenClient struct {
	mu          sync.Mutex
	token       string
	tokenErr    error
	callsByScope map[string]int
}

func newStubTokenClient(token string) *stubTokenClient {
	return &stubTokenClient{
		token:        token,
		callsByScope: make(map[string]int),
	}
}

func (s *stubTokenClient) ServiceToken(ctx context.Context, scope string) (string, error) {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.callsByScope[scope]++
	if s.tokenErr != nil {
		return "", s.tokenErr
	}
	return s.token, nil
}

func (s *stubTokenClient) IssueDelegatedDownload(ctx context.Context, in IssueDownloadReq) (*DelegatedDownloadToken, error) {
	// converter_client 不會呼叫；此處只是滿足 interface
	return nil, fmt.Errorf("stubTokenClient.IssueDelegatedDownload should not be called from converter_client tests")
}

func (s *stubTokenClient) setError(err error) {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.tokenErr = err
}

func (s *stubTokenClient) calls(scope string) int {
	s.mu.Lock()
	defer s.mu.Unlock()
	return s.callsByScope[scope]
}

// ==========================================================================
// converter mock server helpers
// ==========================================================================

// newConverterClientForTest 建立指向 mock server 的 ConverterClient。
//
// 使用較短的 init/http timeout 加速 test；retry 退避保持原本（converterRetryBackoff 1s 起跳
// 對 retry test 有點久但仍可接受 — 5xx retry test 的 max 2 retries = 0.5s + 1s = 1.5s）。
func newConverterClientForTest(t *testing.T, baseURL string, tokens MCTokenClient) ConverterClient {
	t.Helper()
	return NewConverterClient(ConverterClientOpts{
		BaseURL:        baseURL,
		Tokens:         tokens,
		HTTPClient:     &http.Client{Timeout: 5 * time.Second},
		InitHTTPClient: &http.Client{Timeout: 5 * time.Second},
		Logger:         silentLogger(),
	})
}

// ==========================================================================
// InitJob tests
// ==========================================================================

// TestInitJob_Success：mock 接受 multipart，回 201 + job spec。
func TestInitJob_Success(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var serverContentType string
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		require.Equal(t, http.MethodPost, r.Method)
		require.Equal(t, "Bearer svc-tok", r.Header.Get("Authorization"))
		serverContentType = r.Header.Get("Content-Type")

		// drain body 確認 streaming 完成
		_, _ = io.Copy(io.Discard, r.Body)

		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusCreated)
		_, _ = w.Write([]byte(`{
			"job_id": "550e8400-e29b-41d4-a716-446655440000",
			"status": "created",
			"stage": "onnx",
			"progress": 0,
			"created_at": "2026-04-25T12:00:00Z",
			"updated_at": "2026-04-25T12:00:00Z",
			"expires_at": "2026-05-02T12:00:00Z",
			"user_id": "alice"
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	job, err := cc.InitJob(context.Background(), InitConverterJobReq{
		UserID:          "alice",
		Platform:        "520",
		SourceFilename:  "model.onnx",
		Body:            strings.NewReader("--xyz\r\nContent-Disposition: form-data; name=\"user_id\"\r\n\r\nalice\r\n--xyz--\r\n"),
		BodyContentType: "multipart/form-data; boundary=xyz",
	})

	require.NoError(t, err)
	require.NotNil(t, job)
	assert.Equal(t, "550e8400-e29b-41d4-a716-446655440000", job.JobID)
	assert.Equal(t, "created", job.Status)
	assert.Equal(t, "onnx", job.Stage)
	assert.Equal(t, "multipart/form-data; boundary=xyz", serverContentType,
		"InitJob 必須完整透傳 Content-Type 含 boundary（converter multer 解析依賴此）")
	assert.Equal(t, 1, tokens.calls(scopeConverterWrite))
}

// TestInitJob_StreamingBody：driver 寫 100MB 假資料給 io.Reader，confirm streaming（不全 buffer RAM）。
//
// 用 io.LimitReader 包一個無限 reader，server side 也用 io.Discard 不存。
// 觀察：peakReadBytes 不應接近 100MB（確認 net/http 真的是 streaming）— 但 peak 偵測在 Go 層級不易，
// 改驗：reader 的 ReadCalls 數應遠大於 1（如果 buffer 全進 RAM，net/http 會一次全讀）。
func TestInitJob_StreamingBody(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var serverBytesRead int64
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		// 不一次 ReadAll；用 Copy 到 io.Discard 強制 streaming
		n, _ := io.Copy(io.Discard, r.Body)
		atomic.AddInt64(&serverBytesRead, n)

		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusCreated)
		_, _ = w.Write([]byte(`{
			"job_id": "stream-test", "status": "created", "stage": "onnx", "progress": 0,
			"created_at": "2026-04-25T12:00:00Z",
			"updated_at": "2026-04-25T12:00:00Z",
			"expires_at": "2026-05-02T12:00:00Z"
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	const totalSize = int64(10 * 1024 * 1024) // 10MB（測試成本與 streaming 驗證的平衡）
	reader := &countingReader{
		R: io.LimitReader(zerosReader{}, totalSize),
	}

	cc := newConverterClientForTest(t, srv.URL, tokens)
	// 對 streaming test 加長 timeout
	cc = NewConverterClient(ConverterClientOpts{
		BaseURL:        srv.URL,
		Tokens:         tokens,
		HTTPClient:     &http.Client{Timeout: 30 * time.Second},
		InitHTTPClient: &http.Client{Timeout: 30 * time.Second},
		Logger:         silentLogger(),
	})

	job, err := cc.InitJob(context.Background(), InitConverterJobReq{
		UserID:          "alice",
		Body:            reader,
		BodyContentType: "multipart/form-data; boundary=stream",
	})

	require.NoError(t, err)
	require.NotNil(t, job)
	assert.Equal(t, "stream-test", job.JobID)
	assert.Equal(t, totalSize, atomic.LoadInt64(&serverBytesRead),
		"server 應該收到完整 body（streaming proxy 不掉資料）")

	// streaming 證據：reader 應被多次呼叫 Read（如果是 buffer 全 RAM 模式，會一次大讀）
	calls := atomic.LoadInt64(&reader.calls)
	assert.Greater(t, calls, int64(1), "streaming 必須多次 Read（不能一次性 buffer 全 RAM）")
}

// TestInitJob_ContentTypeHeader：multipart boundary 必須完整透傳。
func TestInitJob_ContentTypeHeader(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var receivedCT string
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		receivedCT = r.Header.Get("Content-Type")
		_, _ = io.Copy(io.Discard, r.Body)
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusCreated)
		_, _ = w.Write([]byte(`{
			"job_id": "ct-test", "status": "created", "stage": "onnx", "progress": 0,
			"created_at": "2026-04-25T12:00:00Z",
			"updated_at": "2026-04-25T12:00:00Z",
			"expires_at": "2026-05-02T12:00:00Z"
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	const customCT = "multipart/form-data; boundary=---xxx-very-specific-boundary-yyy---"
	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.InitJob(context.Background(), InitConverterJobReq{
		Body:            strings.NewReader("body content"),
		BodyContentType: customCT,
	})
	require.NoError(t, err)
	assert.Equal(t, customCT, receivedCT, "boundary 必須一字不差透傳（含特殊字元）")
}

// TestInitJob_Conflict409_ActiveJobError：mock 回 409 user_has_active_job → return *ActiveJobError。
func TestInitJob_Conflict409_ActiveJobError(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		_, _ = io.Copy(io.Discard, r.Body)
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusConflict)
		_, _ = w.Write([]byte(`{
			"error": {
				"code": "user_has_active_job",
				"message": "使用者目前已有進行中的轉檔任務",
				"details": {
					"active_job_id": "550e8400-e29b-41d4-a716-446655440000",
					"active_job_status": "running",
					"active_job_stage": "bie",
					"active_job_progress": 45,
					"active_job_created_at": "2026-04-25T12:00:00Z"
				},
				"request_id": "req-123"
			}
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.InitJob(context.Background(), InitConverterJobReq{
		Body:            strings.NewReader("x"),
		BodyContentType: "multipart/form-data; boundary=xxx",
	})

	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrActiveJobExists), "必須能透過 errors.Is 比對 sentinel")

	var ae *ActiveJobError
	require.True(t, errors.As(err, &ae), "必須能透過 errors.As 取出 ActiveJobError struct")
	require.NotNil(t, ae.Job)
	assert.Equal(t, "550e8400-e29b-41d4-a716-446655440000", ae.Job.JobID)
	assert.Equal(t, "running", ae.Job.Status)
	assert.Equal(t, "bie", ae.Job.Stage)
	assert.Equal(t, 45, ae.Job.Progress)
}

// TestInitJob_Validation400：mock 回 400 + fields → return *ConverterValidationError，
// fields 對齊 openapi.yaml shape（[]ValidationFieldError）。
func TestInitJob_Validation400(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		_, _ = io.Copy(io.Discard, r.Body)
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusBadRequest)
		_, _ = w.Write([]byte(`{
			"error": {
				"code": "validation_error",
				"message": "欄位驗證失敗",
				"details": {
					"fields": [
						{"field": "model_id", "message": "model_id 範圍必須在 1 ~ 65535"},
						{"field": "platform", "message": "platform 必須是 520 / 720 / 530 / 630 / 730"}
					]
				},
				"request_id": "req-validation"
			}
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.InitJob(context.Background(), InitConverterJobReq{
		Body:            strings.NewReader("x"),
		BodyContentType: "multipart/form-data; boundary=xxx",
	})

	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrValidationFailed))

	var ve *ConverterValidationError
	require.True(t, errors.As(err, &ve))
	require.Len(t, ve.Fields, 2, "fields 必須對齊 converter openapi.yaml 的 array shape")
	assert.Equal(t, "model_id", ve.Fields[0].Field)
	assert.Equal(t, "model_id 範圍必須在 1 ~ 65535", ve.Fields[0].Message)
	assert.Equal(t, "platform", ve.Fields[1].Field)
	assert.Contains(t, ve.Message, "驗證失敗", "Message 應透傳 converter 原文供 log 用")
}

// TestInitJob_5xx_NoRetry：mock 連續 500 → InitJob 不 retry，立即 return。
//
// 設計理由：multipart body 是 streaming（io.Reader 一次性），retry 會傳到一半的爛資料。
func TestInitJob_5xx_NoRetry(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var counter atomic.Int32
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		counter.Add(1)
		_, _ = io.Copy(io.Discard, r.Body)
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusInternalServerError)
		_, _ = w.Write([]byte(`{"error":{"code":"misconfiguration","message":"...","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.InitJob(context.Background(), InitConverterJobReq{
		Body:            strings.NewReader("x"),
		BodyContentType: "multipart/form-data; boundary=xxx",
	})

	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrConverterUnavailable))
	assert.Equal(t, int32(1), counter.Load(),
		"InitJob 不可 retry 5xx（streaming body 不可 replay）")
}

// TestInitJob_AuthExpired：mock 回 401 → return ErrServiceClientUnauthorized。
func TestInitJob_AuthExpired(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("expired-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		_, _ = io.Copy(io.Discard, r.Body)
		w.WriteHeader(http.StatusUnauthorized)
		_, _ = w.Write([]byte(`{"error":{"code":"invalid_token","message":"...","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.InitJob(context.Background(), InitConverterJobReq{
		Body:            strings.NewReader("x"),
		BodyContentType: "multipart/form-data; boundary=xxx",
	})

	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrServiceClientUnauthorized))
}

// TestInitJob_TokenFailure_Propagated：MCTokenClient 取 token 失敗時，錯誤透傳。
func TestInitJob_TokenFailure_Propagated(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("")
	tokens.setError(ErrServiceClientUnauthorized)

	cc := newConverterClientForTest(t, "http://unused", tokens)
	_, err := cc.InitJob(context.Background(), InitConverterJobReq{
		Body:            strings.NewReader("x"),
		BodyContentType: "multipart/form-data; boundary=xxx",
	})

	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrServiceClientUnauthorized))
}

// TestInitJob_RequiredFieldsValidation：本地參數驗證（不打網路）。
func TestInitJob_RequiredFieldsValidation(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	cc := newConverterClientForTest(t, "http://unused", tokens)

	// 缺 body
	_, err := cc.InitJob(context.Background(), InitConverterJobReq{
		BodyContentType: "multipart/form-data; boundary=x",
	})
	require.Error(t, err)
	assert.Contains(t, err.Error(), "body is required")

	// 缺 content type
	_, err = cc.InitJob(context.Background(), InitConverterJobReq{
		Body: strings.NewReader("x"),
	})
	require.Error(t, err)
	assert.Contains(t, err.Error(), "content type is required")
}

// ==========================================================================
// GetJob tests
// ==========================================================================

// TestGetJob_Success：標準 happy path（含完整 Job shape 解析）。
func TestGetJob_Success(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		require.Equal(t, http.MethodGet, r.Method)
		require.Equal(t, "Bearer svc-tok", r.Header.Get("Authorization"))
		// path: /api/v1/jobs/{id}
		assert.Contains(t, r.URL.Path, "550e8400")
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{
			"job_id": "550e8400-e29b-41d4-a716-446655440000",
			"user_id": "alice",
			"status": "running",
			"stage": "bie",
			"progress": 45,
			"stage_progress": 60,
			"created_at": "2026-04-25T12:00:00Z",
			"updated_at": "2026-04-25T12:05:30Z",
			"expires_at": "2026-05-02T12:00:00Z",
			"input": {"filename": "model.onnx", "size_bytes": 100, "ref_images_count": 0},
			"parameters": {"model_id": 1001, "version": "v1.0.0", "platform": "520"},
			"error": null
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	job, err := cc.GetJob(context.Background(), "550e8400-e29b-41d4-a716-446655440000")
	require.NoError(t, err)
	require.NotNil(t, job)
	assert.Equal(t, "running", job.Status)
	assert.Equal(t, "bie", job.Stage)
	require.NotNil(t, job.Progress)
	assert.Equal(t, 45, *job.Progress)
	require.NotNil(t, job.StageProgress)
	assert.Equal(t, 60, *job.StageProgress)
	assert.Equal(t, "model.onnx", job.SourceFilename)
	assert.Equal(t, "520", job.Platform)
	assert.False(t, job.ExpiresAt.IsZero())
}

// TestGetJob_NotFound：404 → ErrJobNotFound。
func TestGetJob_NotFound(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusNotFound)
		_, _ = w.Write([]byte(`{"error":{"code":"job_not_found","message":"...","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.GetJob(context.Background(), "missing-job")
	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrJobNotFound))
}

// TestGetJob_5xx_RetryThenSuccess：500/500/200 → atomic counter 驗 retry 3 次。
func TestGetJob_5xx_RetryThenSuccess(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var counter atomic.Int32
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		idx := counter.Add(1)
		if idx <= 2 {
			w.WriteHeader(http.StatusInternalServerError)
			_, _ = w.Write([]byte(`{"error":{"code":"internal_error","message":"...","request_id":"r"}}`))
			return
		}
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{
			"job_id": "j1", "status": "completed", "stage": null, "progress": 100,
			"created_at": "2026-04-25T12:00:00Z",
			"updated_at": "2026-04-25T12:08:30Z",
			"expires_at": "2026-05-02T12:00:00Z"
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	job, err := cc.GetJob(context.Background(), "j1")
	require.NoError(t, err)
	require.NotNil(t, job)
	assert.Equal(t, "completed", job.Status)
	assert.Equal(t, int32(3), counter.Load(), "GetJob 應 retry max 2 次（共 3 attempts）")
}

// TestGetJob_5xx_Exhausted：連續 5xx 用完 retry 仍失敗 → ErrConverterUnavailable。
func TestGetJob_5xx_Exhausted(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var counter atomic.Int32
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		counter.Add(1)
		w.WriteHeader(http.StatusBadGateway)
		_, _ = w.Write([]byte(`{"error":{"code":"x","message":"x","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.GetJob(context.Background(), "j1")
	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrConverterUnavailable))
	assert.Equal(t, int32(3), counter.Load(), "用完 retry 仍 5xx 應該打 3 次")
}

// TestGetJob_ContextCancel_NoRetry：ctx 在 retry 等待中被 cancel → 立即 return。
func TestGetJob_ContextCancel_NoRetry(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var counter atomic.Int32
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		counter.Add(1)
		w.WriteHeader(http.StatusInternalServerError)
		_, _ = w.Write([]byte(`{"error":{"code":"x","message":"x","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)

	ctx, cancel := context.WithCancel(context.Background())
	// 第一次 attempt 完後 cancel；第二次 retry 等待時應立即 return
	go func() {
		time.Sleep(50 * time.Millisecond)
		cancel()
	}()

	_, err := cc.GetJob(ctx, "j1")
	require.Error(t, err)
	assert.True(t, errors.Is(err, context.Canceled))
	// 至多 1 次（cancel 在退避時觸發）
	assert.LessOrEqual(t, counter.Load(), int32(1),
		"ctx cancel 應在第 1 次 attempt 後立即 return，不再打 server")
}

// ==========================================================================
// Promote tests
// ==========================================================================

// TestPromote_Success：promote response 含 target_object_key。
func TestPromote_Success(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var receivedBody string
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		require.Equal(t, http.MethodPost, r.Method)
		assert.Contains(t, r.URL.Path, "/promote")
		body, _ := io.ReadAll(r.Body)
		receivedBody = string(body)

		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{
			"job_id": "j1",
			"promoted": [
				{
					"source": "nef",
					"target_object_key": "visionA/models/alice/m-1001/v1.0.0/out.nef",
					"size_bytes": 10485760,
					"file_access_agent_etag": "abc123",
					"promoted_at": "2026-04-25T12:30:00Z"
				}
			]
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	result, err := cc.Promote(context.Background(), "j1", PromoteReq{
		UserID:          "alice",
		Source:          "nef",
		TargetObjectKey: "visionA/models/alice/m-1001/v1.0.0/out.nef",
	})
	require.NoError(t, err)
	require.NotNil(t, result)
	assert.Equal(t, "visionA/models/alice/m-1001/v1.0.0/out.nef", result.TargetObjectKey)
	assert.Equal(t, int64(10485760), result.Size)
	assert.Equal(t, "abc123", result.Checksum)
	assert.Contains(t, receivedBody, `"user_id":"alice"`,
		"promote body 應含 user_id metadata（trust boundary 重申）")
	assert.Contains(t, receivedBody, `"target_object_key":"visionA/models/alice/m-1001/v1.0.0/out.nef"`)
}

// TestPromote_DefaultSource：未傳 Source 時預設 nef。
func TestPromote_DefaultSource(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var receivedBody string
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		body, _ := io.ReadAll(r.Body)
		receivedBody = string(body)
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{
			"job_id": "j1",
			"promoted": [{"source":"nef","target_object_key":"x","size_bytes":1,"file_access_agent_etag":"","promoted_at":"2026-04-25T00:00:00Z"}]
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.Promote(context.Background(), "j1", PromoteReq{
		UserID:          "alice",
		TargetObjectKey: "x",
	})
	require.NoError(t, err)
	assert.Contains(t, receivedBody, `"source":"nef"`, "未傳 Source 時應預設 nef")
}

// TestPromote_BadGateway：FAA 不可達 → 502 → ErrFAAUnavailable。
func TestPromote_BadGateway(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusBadGateway)
		_, _ = w.Write([]byte(`{"error":{"code":"file_gateway_unavailable","message":"FAA 不可達","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.Promote(context.Background(), "j1", PromoteReq{
		UserID:          "alice",
		TargetObjectKey: "x",
	})
	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrFAAUnavailable),
		"converter 502 file_gateway_unavailable 必須對應到 ErrFAAUnavailable")
}

// TestPromote_NotCompleted409：job_not_ready_for_promote → ErrJobNotCompleted。
func TestPromote_NotCompleted409(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusConflict)
		_, _ = w.Write([]byte(`{"error":{"code":"job_not_ready_for_promote","message":"...","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.Promote(context.Background(), "j1", PromoteReq{
		UserID:          "alice",
		TargetObjectKey: "x",
	})
	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrJobNotCompleted))
}

// TestPromote_NotFound404：404 → ErrJobNotFound。
func TestPromote_NotFound404(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs/", func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusNotFound)
		_, _ = w.Write([]byte(`{"error":{"code":"job_not_found","message":"...","request_id":"r"}}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	_, err := cc.Promote(context.Background(), "j1", PromoteReq{
		UserID:          "alice",
		TargetObjectKey: "x",
	})
	require.Error(t, err)
	assert.True(t, errors.Is(err, ErrJobNotFound))
}

// TestPromote_RequiredFieldsValidation：本地參數驗證。
func TestPromote_RequiredFieldsValidation(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	cc := newConverterClientForTest(t, "http://unused", tokens)

	_, err := cc.Promote(context.Background(), "", PromoteReq{TargetObjectKey: "x"})
	require.Error(t, err)
	assert.Contains(t, err.Error(), "jobID is required")

	_, err = cc.Promote(context.Background(), "j1", PromoteReq{})
	require.Error(t, err)
	assert.Contains(t, err.Error(), "target_object_key is required")
}

// ==========================================================================
// ListInProgressJobs tests
// ==========================================================================

// TestListInProgressJobs_Success：query string 含 user_id + status=in_progress。
func TestListInProgressJobs_Success(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var receivedQuery string
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		// path 在 mux pattern 沒結尾 / 時 ServeMux 會匹配精確路徑（list 端點）
		require.Equal(t, http.MethodGet, r.Method)
		receivedQuery = r.URL.RawQuery
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{
			"jobs": [
				{
					"job_id": "j-active",
					"user_id": "alice",
					"status": "running",
					"stage": "bie",
					"progress": 45,
					"created_at": "2026-04-25T12:00:00Z",
					"updated_at": "2026-04-25T12:05:30Z",
					"expires_at": "2026-05-02T12:00:00Z",
					"input": {"filename": "model.onnx", "size_bytes": 1, "ref_images_count": 0},
					"parameters": {"model_id": 1, "version": "v1.0.0", "platform": "720"},
					"error": null
				}
			],
			"total": 1,
			"next_cursor": null
		}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	jobs, err := cc.ListInProgressJobs(context.Background(), "alice")
	require.NoError(t, err)
	require.Len(t, jobs, 1)
	assert.Equal(t, "j-active", jobs[0].JobID)
	assert.Equal(t, "running", jobs[0].Status)
	assert.Equal(t, "bie", jobs[0].Stage)
	assert.Equal(t, "720", jobs[0].Platform)
	assert.Contains(t, receivedQuery, "user_id=alice")
	assert.Contains(t, receivedQuery, "status=in_progress",
		"必須帶 status=in_progress 給 lazy rebuild ownership 用")
}

// TestListInProgressJobs_Empty：[] response → 空 slice。
func TestListInProgressJobs_Empty(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{"jobs":[],"total":0,"next_cursor":null}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	jobs, err := cc.ListInProgressJobs(context.Background(), "alice")
	require.NoError(t, err)
	assert.Len(t, jobs, 0, "empty result 應回空 slice，不是 nil 也不是 error")
	assert.NotNil(t, jobs, "應回非 nil 空 slice 給 caller 安全 range")
}

// TestListInProgressJobs_5xxRetry：5xx 後成功；驗 retry 1 次（共 2 attempts）。
func TestListInProgressJobs_5xxRetry(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	var counter atomic.Int32
	mux := http.NewServeMux()
	mux.HandleFunc("/api/v1/jobs", func(w http.ResponseWriter, r *http.Request) {
		idx := counter.Add(1)
		if idx == 1 {
			w.WriteHeader(http.StatusInternalServerError)
			_, _ = w.Write([]byte(`{"error":{"code":"x","message":"x","request_id":"r"}}`))
			return
		}
		w.Header().Set("Content-Type", "application/json")
		w.WriteHeader(http.StatusOK)
		_, _ = w.Write([]byte(`{"jobs":[],"total":0,"next_cursor":null}`))
	})
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)

	cc := newConverterClientForTest(t, srv.URL, tokens)
	jobs, err := cc.ListInProgressJobs(context.Background(), "alice")
	require.NoError(t, err)
	assert.Len(t, jobs, 0)
	assert.Equal(t, int32(2), counter.Load(), "List 應 retry 1 次（共 2 attempts）")
}

// TestListInProgressJobs_RequiredUserID：本地參數驗證。
func TestListInProgressJobs_RequiredUserID(t *testing.T) {
	t.Parallel()

	tokens := newStubTokenClient("svc-tok")
	cc := newConverterClientForTest(t, "http://unused", tokens)

	_, err := cc.ListInProgressJobs(context.Background(), "")
	require.Error(t, err)
	assert.Contains(t, err.Error(), "userID is required")
}

// ==========================================================================
// 共用：interface 契約 + helpers
// ==========================================================================

// 確保 converterClient 滿足 ConverterClient interface（compile-time check）。
var _ ConverterClient = (*converterClient)(nil)

// 確保 stubTokenClient 滿足 MCTokenClient interface（compile-time check）。
var _ MCTokenClient = (*stubTokenClient)(nil)

// zerosReader 是無限產生 0 byte 的 reader（測 streaming 用）。
type zerosReader struct{}

func (zerosReader) Read(p []byte) (int, error) {
	for i := range p {
		p[i] = 0
	}
	return len(p), nil
}

// countingReader 包一個 reader 並計數 Read 呼叫次數（給 streaming 驗證用）。
type countingReader struct {
	R     io.Reader
	calls int64 // atomic
}

func (c *countingReader) Read(p []byte) (int, error) {
	atomic.AddInt64(&c.calls, 1)
	return c.R.Read(p)
}