package api

import (
	"bytes"
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"path/filepath"
	"strconv"
	"testing"
	"time"

	"smartrun/backend/internal/garmin/mock"
	"smartrun/backend/internal/store"
	appsync "smartrun/backend/internal/sync"
)

func newCtx() context.Context { return context.Background() }

func newTestServer(t *testing.T) (*Server, *store.DB) {
	t.Helper()
	db, err := store.Open(filepath.Join(t.TempDir(), "smartrun_test.db"))
	if err != nil {
		t.Fatalf("store.Open: %v", err)
	}
	t.Cleanup(func() { db.Close() })

	m := &mock.Client{}
	svc := appsync.NewService(m, db, appsync.Config{}, func() time.Time { return time.Date(2026, 7, 11, 0, 0, 0, 0, time.UTC) })
	return NewServer(db, m, svc), db
}

func doJSON(t *testing.T, handler http.Handler, method, path string, body any) *httptest.ResponseRecorder {
	t.Helper()
	var reader *bytes.Reader
	if body != nil {
		b, err := json.Marshal(body)
		if err != nil {
			t.Fatalf("marshal request body: %v", err)
		}
		reader = bytes.NewReader(b)
	} else {
		reader = bytes.NewReader(nil)
	}
	req := httptest.NewRequest(method, path, reader)
	req.Header.Set("Content-Type", "application/json")
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)
	return rec
}

func TestHealth(t *testing.T) {
	s, _ := newTestServer(t)
	rec := doJSON(t, s.Router(), http.MethodGet, "/api/health", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want 200", rec.Code)
	}
}

func TestWorkoutKindList_ReturnsEightSeededTypesWithPaceFields(t *testing.T) {
	s, _ := newTestServer(t)
	rec := doJSON(t, s.Router(), http.MethodGet, "/api/workout-kinds/", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d", rec.Code)
	}
	var kinds []workoutKindResponse
	if err := json.Unmarshal(rec.Body.Bytes(), &kinds); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if len(kinds) != 8 {
		t.Fatalf("expected 8 seeded kinds, got %d", len(kinds))
	}
	for _, k := range kinds {
		if k.PaceMinSecPerKm != nil || k.PaceMaxSecPerKm != nil || k.ExpectedHRZone != nil {
			t.Errorf("expected freshly-seeded kind %q to have nil pace fields, got %+v", k.Name, k)
		}
	}
}

func TestWorkoutKindUpdate_SetsRuleAndPace(t *testing.T) {
	s, _ := newTestServer(t)
	router := s.Router()

	rec := doJSON(t, router, http.MethodGet, "/api/workout-kinds/", nil)
	var kinds []workoutKindResponse
	json.Unmarshal(rec.Body.Bytes(), &kinds)
	target := kinds[0]

	minPace, maxPace, zone := 330.0, 420.0, 2
	body := map[string]any{
		"name":                target.Name,
		"rule":                json.RawMessage(`{"match":"all","conditions":[{"metric":"avg_pace_sec_per_km","op":"between","value":[270,300]}]}`),
		"pace_min_sec_per_km": minPace,
		"pace_max_sec_per_km": maxPace,
		"expected_hr_zone":    zone,
	}
	rec = doJSON(t, router, http.MethodPut, "/api/workout-kinds/"+itoa(target.ID), body)
	if rec.Code != http.StatusOK {
		t.Fatalf("update status = %d, body = %s", rec.Code, rec.Body.String())
	}

	rec = doJSON(t, router, http.MethodGet, "/api/workout-kinds/"+itoa(target.ID), nil)
	var updated workoutKindResponse
	json.Unmarshal(rec.Body.Bytes(), &updated)
	if updated.PaceMinSecPerKm == nil || *updated.PaceMinSecPerKm != 330 {
		t.Errorf("PaceMinSecPerKm = %v, want 330", updated.PaceMinSecPerKm)
	}
	if updated.ExpectedHRZone == nil || *updated.ExpectedHRZone != 2 {
		t.Errorf("ExpectedHRZone = %v, want 2", updated.ExpectedHRZone)
	}
}

func TestWorkoutKindUpdate_RejectsInvalidRule(t *testing.T) {
	s, _ := newTestServer(t)
	router := s.Router()

	rec := doJSON(t, router, http.MethodGet, "/api/workout-kinds/", nil)
	var kinds []workoutKindResponse
	json.Unmarshal(rec.Body.Bytes(), &kinds)

	rec = doJSON(t, router, http.MethodPut, "/api/workout-kinds/"+itoa(kinds[0].ID), map[string]any{
		"name": kinds[0].Name,
		"rule": json.RawMessage(`{"match":"xor","conditions":[]}`),
	})
	if rec.Code != http.StatusBadRequest {
		t.Fatalf("status = %d, want 400, body = %s", rec.Code, rec.Body.String())
	}
}

func TestWorkoutKindUpdate_RejectsInvalidHRZone(t *testing.T) {
	s, _ := newTestServer(t)
	router := s.Router()

	rec := doJSON(t, router, http.MethodGet, "/api/workout-kinds/", nil)
	var kinds []workoutKindResponse
	json.Unmarshal(rec.Body.Bytes(), &kinds)

	rec = doJSON(t, router, http.MethodPut, "/api/workout-kinds/"+itoa(kinds[0].ID), map[string]any{
		"name":             kinds[0].Name,
		"rule":             json.RawMessage(`{"match":"all","conditions":[]}`),
		"expected_hr_zone": 9,
	})
	if rec.Code != http.StatusBadRequest {
		t.Fatalf("status = %d, want 400, body = %s", rec.Code, rec.Body.String())
	}
}

func TestReviewQueueResolve(t *testing.T) {
	s, db := newTestServer(t)
	ctx := newCtx()

	activityID, err := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 1, ActivityType: "running", StartTimeUTC: "2026-07-11 06:00:00", RawJSON: "{}"})
	if err != nil {
		t.Fatalf("UpsertActivity: %v", err)
	}
	kindID, err := db.CreateWorkoutKind(ctx, store.WorkoutKind{Name: "Easy", RuleJSON: `{"match":"all","conditions":[]}`, IsActive: true})
	if err != nil {
		t.Fatalf("CreateWorkoutKind: %v", err)
	}
	if _, err := db.InsertKindAssignment(ctx, store.KindAssignment{
		ActivityID: activityID, AssignmentSource: store.AssignmentSourceRuleEngine, Status: store.AssignmentStatusNeedsReview,
		CandidateKindsJSON: "[]",
	}); err != nil {
		t.Fatalf("InsertKindAssignment: %v", err)
	}
	targetLow, targetHigh := 3.0, 3.5
	if err := db.ReplaceLaps(ctx, activityID, []store.Lap{
		{LapIndex: 1, TargetPaceLowMps: &targetLow, TargetPaceHighMps: &targetHigh},
	}); err != nil {
		t.Fatalf("ReplaceLaps: %v", err)
	}
	hr := 150.0
	if err := db.ReplaceActivitySamples(ctx, activityID, []store.Sample{
		{ElapsedSeconds: 0, HeartRate: &hr},
	}); err != nil {
		t.Fatalf("ReplaceActivitySamples: %v", err)
	}

	router := s.Router()
	rec := doJSON(t, router, http.MethodGet, "/api/review-queue/", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("review queue status = %d", rec.Code)
	}
	var queue []map[string]any
	json.Unmarshal(rec.Body.Bytes(), &queue)
	if len(queue) != 1 {
		t.Fatalf("expected 1 item in review queue, got %d: %s", len(queue), rec.Body.String())
	}
	laps, _ := queue[0]["laps"].([]any)
	if len(laps) != 1 {
		t.Fatalf("expected 1 lap in review queue item, got %d: %s", len(laps), rec.Body.String())
	}
	samples, _ := queue[0]["samples"].([]any)
	if len(samples) != 1 {
		t.Fatalf("expected 1 sample in review queue item, got %d: %s", len(samples), rec.Body.String())
	}

	rec = doJSON(t, router, http.MethodPost, "/api/review-queue/"+itoa(activityID)+"/resolve", map[string]any{"workout_kind_id": kindID})
	if rec.Code != http.StatusOK {
		t.Fatalf("resolve status = %d, body = %s", rec.Code, rec.Body.String())
	}

	rec = doJSON(t, router, http.MethodGet, "/api/review-queue/", nil)
	json.Unmarshal(rec.Body.Bytes(), &queue)
	if len(queue) != 0 {
		t.Fatalf("expected empty review queue after resolve, got %d", len(queue))
	}
}

func TestResolveReview_RejectsRaceKind(t *testing.T) {
	s, db := newTestServer(t)
	ctx := newCtx()

	activityID, err := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 1, ActivityType: "running", StartTimeUTC: "2026-07-11 06:00:00", RawJSON: "{}"})
	if err != nil {
		t.Fatalf("UpsertActivity: %v", err)
	}
	raceKind, ok, err := db.GetWorkoutKindByName(ctx, "Race")
	if err != nil || !ok {
		t.Fatalf("GetWorkoutKindByName(Race): ok=%v err=%v", ok, err)
	}

	rec := doJSON(t, s.Router(), http.MethodPost, "/api/review-queue/"+itoa(activityID)+"/resolve", map[string]any{"workout_kind_id": raceKind.ID})
	if rec.Code != http.StatusBadRequest {
		t.Fatalf("resolve to Race status = %d, want 400, body = %s", rec.Code, rec.Body.String())
	}
}

func TestReclassifyAll_SkipsManualAndRaceAssignments(t *testing.T) {
	s, db := newTestServer(t)
	ctx := newCtx()

	easyID, err := db.CreateWorkoutKind(ctx, store.WorkoutKind{Name: "Test Easy", RuleJSON: `{"match":"all","conditions":[{"metric":"distance_meters","op":">=","value":0}]}`, IsActive: true})
	if err != nil {
		t.Fatalf("CreateWorkoutKind: %v", err)
	}
	raceKind, ok, err := db.GetWorkoutKindByName(ctx, "Race")
	if err != nil || !ok {
		t.Fatalf("GetWorkoutKindByName(Race): ok=%v err=%v", ok, err)
	}

	ruleEngineActivity, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 1, ActivityType: "running", StartTimeUTC: "2026-07-01 06:00:00", RawJSON: "{}"})
	manualActivity, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 2, ActivityType: "running", StartTimeUTC: "2026-07-02 06:00:00", RawJSON: "{}"})
	raceActivity, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 3, ActivityType: "running", EventTypeKey: "race", StartTimeUTC: "2026-07-03 06:00:00", RawJSON: "{}"})

	if _, err := db.InsertKindAssignment(ctx, store.KindAssignment{
		ActivityID: ruleEngineActivity, WorkoutKindID: &easyID, AssignmentSource: store.AssignmentSourceRuleEngine,
		Status: store.AssignmentStatusAssigned, CandidateKindsJSON: "[]",
	}); err != nil {
		t.Fatalf("InsertKindAssignment (rule engine): %v", err)
	}
	if _, err := db.InsertKindAssignment(ctx, store.KindAssignment{
		ActivityID: manualActivity, WorkoutKindID: &easyID, AssignmentSource: store.AssignmentSourceManual,
		Status: store.AssignmentStatusAssigned, CandidateKindsJSON: "[]",
	}); err != nil {
		t.Fatalf("InsertKindAssignment (manual): %v", err)
	}
	if _, err := db.InsertKindAssignment(ctx, store.KindAssignment{
		ActivityID: raceActivity, WorkoutKindID: &raceKind.ID, AssignmentSource: store.AssignmentSourceRuleEngine,
		Status: store.AssignmentStatusAssigned, CandidateKindsJSON: "[]",
	}); err != nil {
		t.Fatalf("InsertKindAssignment (race): %v", err)
	}

	rec := doJSON(t, s.Router(), http.MethodPost, "/api/reclassify", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("reclassify status = %d, body = %s", rec.Code, rec.Body.String())
	}
	var body struct {
		Reclassified int `json:"reclassified"`
	}
	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if body.Reclassified != 1 {
		t.Fatalf("reclassified = %d, want 1 (only the non-locked rule-engine activity)", body.Reclassified)
	}

	manualAssignment, ok, err := db.CurrentAssignment(ctx, manualActivity)
	if err != nil || !ok {
		t.Fatalf("CurrentAssignment(manual): ok=%v err=%v", ok, err)
	}
	if manualAssignment.AssignmentSource != store.AssignmentSourceManual {
		t.Errorf("manual assignment was overwritten: %+v", manualAssignment)
	}

	raceAssignment, ok, err := db.CurrentAssignment(ctx, raceActivity)
	if err != nil || !ok {
		t.Fatalf("CurrentAssignment(race): ok=%v err=%v", ok, err)
	}
	if raceAssignment.WorkoutKindID == nil || *raceAssignment.WorkoutKindID != raceKind.ID {
		t.Errorf("race assignment changed: %+v", raceAssignment)
	}
}

func TestListActivities_ReportsLockedForManualAndRaceAssignments(t *testing.T) {
	s, db := newTestServer(t)
	ctx := newCtx()

	easyID, err := db.CreateWorkoutKind(ctx, store.WorkoutKind{Name: "Test Easy Locked", RuleJSON: `{"match":"all","conditions":[]}`, IsActive: true})
	if err != nil {
		t.Fatalf("CreateWorkoutKind: %v", err)
	}
	raceKind, ok, err := db.GetWorkoutKindByName(ctx, "Race")
	if err != nil || !ok {
		t.Fatalf("GetWorkoutKindByName(Race): ok=%v err=%v", ok, err)
	}

	ruleEngineActivity, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 1, ActivityType: "running", StartTimeUTC: "2026-07-01 06:00:00", RawJSON: "{}"})
	manualActivity, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 2, ActivityType: "running", StartTimeUTC: "2026-07-02 06:00:00", RawJSON: "{}"})
	raceActivity, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 3, ActivityType: "running", EventTypeKey: "race", StartTimeUTC: "2026-07-03 06:00:00", RawJSON: "{}"})

	db.InsertKindAssignment(ctx, store.KindAssignment{ActivityID: ruleEngineActivity, WorkoutKindID: &easyID, AssignmentSource: store.AssignmentSourceRuleEngine, Status: store.AssignmentStatusAssigned, CandidateKindsJSON: "[]"})
	db.InsertKindAssignment(ctx, store.KindAssignment{ActivityID: manualActivity, WorkoutKindID: &easyID, AssignmentSource: store.AssignmentSourceManual, Status: store.AssignmentStatusAssigned, CandidateKindsJSON: "[]"})
	db.InsertKindAssignment(ctx, store.KindAssignment{ActivityID: raceActivity, WorkoutKindID: &raceKind.ID, AssignmentSource: store.AssignmentSourceRuleEngine, Status: store.AssignmentStatusAssigned, CandidateKindsJSON: "[]"})

	rec := doJSON(t, s.Router(), http.MethodGet, "/api/activities/", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, body = %s", rec.Code, rec.Body.String())
	}
	var items []activityListItem
	if err := json.Unmarshal(rec.Body.Bytes(), &items); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	locked := map[int64]bool{}
	kindName := map[int64]string{}
	for _, it := range items {
		locked[it.ID] = it.Locked
		if it.WorkoutKindName != nil {
			kindName[it.ID] = *it.WorkoutKindName
		}
	}
	if locked[ruleEngineActivity] {
		t.Errorf("rule-engine activity should not be locked")
	}
	if !locked[manualActivity] {
		t.Errorf("manual activity should be locked")
	}
	if !locked[raceActivity] {
		t.Errorf("race activity should be locked")
	}
	if kindName[raceActivity] != "Race" {
		t.Errorf("race activity workout_kind_name = %q, want %q", kindName[raceActivity], "Race")
	}
}

func TestSyncReset_DeletesActivitiesAndBackfillEndpointIsGone(t *testing.T) {
	s, db := newTestServer(t)
	ctx := newCtx()

	if _, err := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 1, ActivityType: "running", StartTimeUTC: "2026-07-11 06:00:00", RawJSON: "{}"}); err != nil {
		t.Fatalf("UpsertActivity: %v", err)
	}

	router := s.Router()
	rec := doJSON(t, router, http.MethodPost, "/api/sync/reset", nil)
	if rec.Code != http.StatusAccepted {
		t.Fatalf("reset status = %d, body = %s", rec.Code, rec.Body.String())
	}

	deadline := time.Now().Add(2 * time.Second)
	for {
		activities, err := db.ListActivities(ctx, store.ActivityFilter{})
		if err != nil {
			t.Fatalf("ListActivities: %v", err)
		}
		if len(activities) == 0 {
			break
		}
		if time.Now().After(deadline) {
			t.Fatalf("timed out waiting for reset to delete activities, still have %d", len(activities))
		}
		time.Sleep(10 * time.Millisecond)
	}

	// "Full backfill" no longer exists as an endpoint -- superseded by reset.
	rec = doJSON(t, router, http.MethodPost, "/api/sync/backfill", nil)
	if rec.Code != http.StatusNotFound {
		t.Errorf("/api/sync/backfill status = %d, want 404 (removed)", rec.Code)
	}
}

func TestProgression_ReturnsSortedTimeSeries(t *testing.T) {
	s, db := newTestServer(t)
	ctx := newCtx()

	kindID, _ := db.CreateWorkoutKind(ctx, store.WorkoutKind{Name: "Easy", RuleJSON: `{}`, IsActive: true})

	speed := 3.0
	a1, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 1, ActivityType: "running", StartTimeUTC: "2026-07-01 06:00:00", AvgSpeedMps: &speed, RawJSON: "{}"})
	a2, _ := db.UpsertActivity(ctx, store.Activity{GarminActivityID: 2, ActivityType: "running", StartTimeUTC: "2026-07-05 06:00:00", AvgSpeedMps: &speed, RawJSON: "{}"})

	for _, id := range []int64{a2, a1} { // insert out of order on purpose
		db.InsertKindAssignment(ctx, store.KindAssignment{ActivityID: id, WorkoutKindID: &kindID, AssignmentSource: store.AssignmentSourceManual, Status: store.AssignmentStatusAssigned, CandidateKindsJSON: "[]"})
	}

	rec := doJSON(t, s.Router(), http.MethodGet, "/api/progression/"+itoa(kindID)+"?metric=pace", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, body = %s", rec.Code, rec.Body.String())
	}
	var points []progressionPoint
	if err := json.Unmarshal(rec.Body.Bytes(), &points); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if len(points) != 2 {
		t.Fatalf("expected 2 points, got %d", len(points))
	}
	if points[0].Date > points[1].Date {
		t.Errorf("points not sorted ascending by date: %+v", points)
	}
}

func itoa(v int64) string {
	return strconv.FormatInt(v, 10)
}

func TestProfile_GetDefaultsThenUpdate(t *testing.T) {
	s, _ := newTestServer(t)
	router := s.Router()

	rec := doJSON(t, router, http.MethodGet, "/api/profile", nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("get status = %d, body = %s", rec.Code, rec.Body.String())
	}
	var got store.Profile
	if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if got.RollingWindowDays != 90 {
		t.Fatalf("RollingWindowDays = %d, want 90", got.RollingWindowDays)
	}

	got.GarminEmail = "runner@example.com"
	got.GarminPassword = "hunter2"
	got.RollingWindowDays = 120
	rec = doJSON(t, router, http.MethodPut, "/api/profile", got)
	if rec.Code != http.StatusOK {
		t.Fatalf("put status = %d, body = %s", rec.Code, rec.Body.String())
	}

	rec = doJSON(t, router, http.MethodGet, "/api/profile", nil)
	var updated store.Profile
	json.Unmarshal(rec.Body.Bytes(), &updated)
	if updated.GarminEmail != "runner@example.com" || updated.RollingWindowDays != 120 {
		t.Fatalf("updated = %+v, want new email/window", updated)
	}
}

func TestProfile_RejectsInvalidHRZones(t *testing.T) {
	s, _ := newTestServer(t)
	router := s.Router()

	rec := doJSON(t, router, http.MethodGet, "/api/profile", nil)
	var p store.Profile
	json.Unmarshal(rec.Body.Bytes(), &p)

	maxHR, restingHR := 100.0, 150.0 // resting > max: invalid
	p.MaxHeartRate = &maxHR
	p.RestingHeartRate = &restingHR

	rec = doJSON(t, router, http.MethodPut, "/api/profile", p)
	if rec.Code != http.StatusBadRequest {
		t.Fatalf("status = %d, want 400, body = %s", rec.Code, rec.Body.String())
	}
}