package control

import (
	"bytes"
	"encoding/json"
	"errors"
	"net/http"
	"net/http/httptest"
	"testing"

	cfgpkg "github.com/jan/fm-rds-tx/internal/config"
	"github.com/jan/fm-rds-tx/internal/audio"
	"github.com/jan/fm-rds-tx/internal/output"
)

func TestHealthz(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/healthz", nil))
	if rec.Code != 200 {
		t.Fatalf("status: %d", rec.Code)
	}
}

func TestStatus(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/status", nil))
	if rec.Code != 200 {
		t.Fatalf("status: %d", rec.Code)
	}
	var body map[string]any
	json.Unmarshal(rec.Body.Bytes(), &body)
	if body["service"] != "fm-rds-tx" {
		t.Fatal("missing service")
	}
	if _, ok := body["preEmphasisTauUS"]; !ok {
		t.Fatal("missing preEmphasisTauUS")
	}
}

func TestStatusReportsRuntimeIndicator(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	srv.SetTXController(&fakeTXController{stats: map[string]any{"runtimeIndicator": "degraded", "runtimeAlert": "late buffers"}})
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/status", nil))
	if rec.Code != 200 {
		t.Fatalf("status: %d", rec.Code)
	}
	var body map[string]any
	json.Unmarshal(rec.Body.Bytes(), &body)
	if body["runtimeIndicator"] != "degraded" {
		t.Fatalf("expected runtimeIndicator degraded, got %v", body["runtimeIndicator"])
	}
	if body["runtimeAlert"] != "late buffers" {
		t.Fatalf("expected runtimeAlert late buffers, got %v", body["runtimeAlert"])
	}
}

func TestStatusReportsQueueStats(t *testing.T) {
	cfg := cfgpkg.Default()
	queueStats := output.QueueStats{
		Capacity:  cfg.Runtime.FrameQueueCapacity,
		Depth:     1,
		FillLevel: 0.25,
		Health:    output.QueueHealthLow,
	}
	srv := NewServer(cfg)
	srv.SetTXController(&fakeTXController{stats: map[string]any{"queue": queueStats}})
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/status", nil))
	if rec.Code != 200 {
		t.Fatalf("status: %d", rec.Code)
	}
	var body map[string]any
	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
		t.Fatalf("unmarshal queue stats: %v", err)
	}
	queueRaw, ok := body["queue"]
	if !ok {
		t.Fatalf("missing queue in status")
	}
	queueMap, ok := queueRaw.(map[string]any)
	if !ok {
		t.Fatalf("queue stats type mismatch: %T", queueRaw)
	}
	if queueMap["capacity"] != float64(queueStats.Capacity) {
		t.Fatalf("queue capacity mismatch: want %v got %v", queueStats.Capacity, queueMap["capacity"])
	}
	if queueMap["health"] != string(queueStats.Health) {
		t.Fatalf("queue health mismatch: want %s got %v", queueStats.Health, queueMap["health"])
	}
}

func TestDryRunEndpoint(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/dry-run", nil))
	if rec.Code != 200 {
		t.Fatalf("status: %d", rec.Code)
	}
	var body map[string]any
	json.Unmarshal(rec.Body.Bytes(), &body)
	if body["mode"] != "dry-run" {
		t.Fatal("wrong mode")
	}
}

func TestConfigPatch(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	body := []byte(`{"toneLeftHz":900,"radioText":"hello world","preEmphasisTauUS":75}`)
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodPost, "/config", bytes.NewReader(body)))
	if rec.Code != 200 {
		t.Fatalf("status: %d body=%s", rec.Code, rec.Body.String())
	}
}

func TestRuntimeWithoutDriver(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/runtime", nil))
	if rec.Code != 200 {
		t.Fatalf("status: %d", rec.Code)
	}
}

func TestRuntimeFaultResetRejectsGet(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet, "/runtime/fault/reset", nil)
	srv.Handler().ServeHTTP(rec, req)
	if rec.Code != http.StatusMethodNotAllowed {
		t.Fatalf("expected 405 for fault reset GET, got %d", rec.Code)
	}
}

func TestRuntimeFaultResetRequiresController(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodPost, "/runtime/fault/reset", nil)
	srv.Handler().ServeHTTP(rec, req)
	if rec.Code != http.StatusServiceUnavailable {
		t.Fatalf("expected 503 without controller, got %d", rec.Code)
	}
}

func TestRuntimeFaultResetControllerError(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	srv.SetTXController(&fakeTXController{resetErr: errors.New("boom")})
	rec := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodPost, "/runtime/fault/reset", nil)
	srv.Handler().ServeHTTP(rec, req)
	if rec.Code != http.StatusConflict {
		t.Fatalf("expected 409 when controller rejects, got %d", rec.Code)
	}
}

func TestRuntimeFaultResetSuccess(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	srv.SetTXController(&fakeTXController{})
	rec := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodPost, "/runtime/fault/reset", nil)
	srv.Handler().ServeHTTP(rec, req)
	if rec.Code != 200 {
		t.Fatalf("expected 200 on success, got %d", rec.Code)
	}
	var body map[string]any
	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
		t.Fatalf("unmarshal response: %v", err)
	}
	if ok, _ := body["ok"].(bool); !ok {
		t.Fatalf("expected ok true, got %v", body["ok"])
	}
}

func TestAudioStreamRequiresSource(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodPost, "/audio/stream", bytes.NewReader(nil))
	srv.Handler().ServeHTTP(rec, req)
	if rec.Code != http.StatusServiceUnavailable {
		t.Fatalf("expected 503 when audio stream missing, got %d", rec.Code)
	}
}

func TestAudioStreamPushesPCM(t *testing.T) {
	cfg := cfgpkg.Default()
	srv := NewServer(cfg)
	stream := audio.NewStreamSource(256, 44100)
	srv.SetStreamSource(stream)
	pcm := []byte{0, 0, 0, 0}
	rec := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodPost, "/audio/stream", bytes.NewReader(pcm))
	srv.Handler().ServeHTTP(rec, req)
	if rec.Code != 200 {
		t.Fatalf("expected 200, got %d", rec.Code)
	}
	var body map[string]any
	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
		t.Fatalf("unmarshal response: %v", err)
	}
	if ok, _ := body["ok"].(bool); !ok {
		t.Fatalf("expected ok true, got %v", body["ok"])
	}
	frames, _ := body["frames"].(float64)
	if frames != 1 {
		t.Fatalf("expected 1 frame, got %v", frames)
	}
	stats, ok := body["stats"].(map[string]any)
	if !ok {
		t.Fatalf("missing stats: %v", body["stats"])
	}
	if avail, _ := stats["available"].(float64); avail < 1 {
		t.Fatalf("expected stats.available >= 1, got %v", avail)
	}
}

func TestAudioStreamRejectsNonPost(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet, "/audio/stream", nil)
	srv.Handler().ServeHTTP(rec, req)
	if rec.Code != http.StatusMethodNotAllowed {
		t.Fatalf("expected 405 for audio stream GET, got %d", rec.Code)
	}
}

func TestTXStartWithoutController(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodPost, "/tx/start", nil))
	if rec.Code != http.StatusServiceUnavailable {
		t.Fatalf("expected 503, got %d", rec.Code)
	}
}

func TestConfigPatchUpdatesSnapshot(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	srv.SetTXController(&fakeTXController{})

	rec := httptest.NewRecorder()
	body := []byte(`{"outputDrive":1.2}`)
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodPost, "/config", bytes.NewReader(body)))
	if rec.Code != 200 {
		t.Fatalf("status: %d", rec.Code)
	}
	var resp map[string]any
	if err := json.Unmarshal(rec.Body.Bytes(), &resp); err != nil {
		t.Fatalf("unmarshal response: %v", err)
	}
	if live, ok := resp["live"].(bool); !ok || !live {
		t.Fatalf("expected live true, got %v", resp["live"])
	}

	rec = httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/config", nil))
	var cfg cfgpkg.Config
	if err := json.NewDecoder(rec.Body).Decode(&cfg); err != nil {
		t.Fatalf("decode config: %v", err)
	}
	if cfg.FM.OutputDrive != 1.2 {
		t.Fatalf("expected snapshot to reflect new drive, got %v", cfg.FM.OutputDrive)
	}
}

func TestConfigPatchEngineRejectsDoesNotUpdateSnapshot(t *testing.T) {
	srv := NewServer(cfgpkg.Default())
	srv.SetTXController(&fakeTXController{updateErr: errors.New("boom")})

	body := []byte(`{"outputDrive":2.2}`)
	rec := httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodPost, "/config", bytes.NewReader(body)))
	if rec.Code != http.StatusBadRequest {
		t.Fatalf("expected 400, got %d", rec.Code)
	}

	rec = httptest.NewRecorder()
	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/config", nil))
	var cfg cfgpkg.Config
	if err := json.NewDecoder(rec.Body).Decode(&cfg); err != nil {
		t.Fatalf("decode config: %v", err)
	}
	if cfg.FM.OutputDrive != cfgpkg.Default().FM.OutputDrive {
		t.Fatalf("expected snapshot untouched, got %v", cfg.FM.OutputDrive)
	}
}

type fakeTXController struct {
	updateErr error
	resetErr  error
	stats     map[string]any
}

func (f *fakeTXController) StartTX() error { return nil }
func (f *fakeTXController) StopTX() error  { return nil }
func (f *fakeTXController) TXStats() map[string]any {
	if f.stats != nil {
		return f.stats
	}
	return map[string]any{}
}
func (f *fakeTXController) UpdateConfig(_ LivePatch) error { return f.updateErr }
func (f *fakeTXController) ResetFault() error { return f.resetErr }