package tts

// 本文件锁定 `Service`（emotionTTS + 既有链的门面）的三条口径：
//
//  1. **健康时用 emotionTTS**，并如实报告级别名 `emotiontts`；
//  2. **失败时回落既有链**，且**不把失败上抛**（文本优先：合成挂掉不影响回复）；
//  3. **未启用时完全透传**（行为与引入本切片之前逐字相同），STT/克隆永远走既有链。

import (
	"context"
	"errors"
	"io"
	"log/slog"
	"net/http"
	"testing"

	mvoice "git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/multimodal/voice"
)

// discardLogger 让测试不往 stderr 刷日志（WARN 的存在由行为断言，不靠肉眼）。
func discardLogger() *slog.Logger {
	return slog.New(slog.NewTextHandler(io.Discard, nil))
}

// fakeChain 是一个可编程的底链替身，记录自己被调了几次。
type fakeChain struct {
	ttsCalls  int
	sttCalls  int
	cloneCall int
	audio     mvoice.Audio
	err       error
}

func (f *fakeChain) STT(context.Context, mvoice.Audio) (string, error) {
	f.sttCalls++
	return "转写文本", nil
}

func (f *fakeChain) STTWithProvider(context.Context, mvoice.Audio) (string, string, error) {
	f.sttCalls++
	return "转写文本", "local", nil
}

func (f *fakeChain) TTS(context.Context, string) (mvoice.Audio, error) {
	f.ttsCalls++
	return f.audio, f.err
}

func (f *fakeChain) TTSWithProvider(context.Context, string) (mvoice.Audio, string, error) {
	f.ttsCalls++
	return f.audio, "silent", f.err
}

func (f *fakeChain) CloneVoice(context.Context, string, string) (string, error) {
	f.cloneCall++
	return "voice-id", nil
}

// TestServiceUsesPrimaryWhenHealthy 钉住主路：健康时走 emotionTTS 且报告级别名。
func TestServiceUsesPrimaryWhenHealthy(t *testing.T) {
	client := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
		_, _ = w.Write(wavBytes("her voice"))
	})
	base := &fakeChain{audio: mvoice.Audio{Format: "mp3", Data: []byte("fallback")}}
	svc := NewService(client, base, WithServiceLogger(discardLogger()))

	audio, rung, err := svc.TTSWithProvider(context.Background(), chineseSpeech)
	if err != nil {
		t.Fatalf("TTSWithProvider: %v", err)
	}
	if rung != ProviderName {
		t.Errorf("rung = %q, want %q", rung, ProviderName)
	}
	if audio.Format != "wav" || string(audio.Data) == "fallback" {
		t.Errorf("audio = %+v, want the emotionTTS bytes", audio)
	}
	if base.ttsCalls != 0 {
		t.Errorf("主路健康却回落了底链 %d 次", base.ttsCalls)
	}
}

// TestServiceFallsBackWhenPrimaryFails 钉住降级：主路失败 ⇒ 底链出声音，
// **错误不上抛**（文本优先）。
func TestServiceFallsBackWhenPrimaryFails(t *testing.T) {
	client := newTestClient(t, func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusInternalServerError)
		_, _ = w.Write([]byte(`{"detail":"indexTTS2 down"}`))
	})
	base := &fakeChain{audio: mvoice.Audio{Format: "mp3", Data: []byte("fallback")}}
	svc := NewService(client, base, WithServiceLogger(discardLogger()))

	audio, rung, err := svc.TTSWithProvider(context.Background(), chineseSpeech)
	if err != nil {
		t.Fatalf("主路失败不该让合成整体失败（文本优先）: %v", err)
	}
	if rung != "silent" {
		t.Errorf("rung = %q, want 底链报告的那一级", rung)
	}
	if string(audio.Data) != "fallback" {
		t.Errorf("audio = %+v, want 底链产物", audio)
	}
	if base.ttsCalls != 1 {
		t.Errorf("底链被调用 %d 次, want 1", base.ttsCalls)
	}
	if got := svc.Stats(); got.Failures != 1 {
		t.Errorf("降级没有计数: %+v", got)
	}
}

// TestServiceDisabledIsTransparent 钉住"未启用 = 行为逐字不变"：底链原样服务，
// 一次都不碰 emotionTTS 的 HTTP。
func TestServiceDisabledIsTransparent(t *testing.T) {
	client := New(Config{Enabled: false, BaseURL: "http://127.0.0.1:1"}, WithLogger(discardLogger()))
	if client.Enabled() {
		t.Fatal("未启用的客户端不该报告 enabled")
	}
	base := &fakeChain{audio: mvoice.Audio{Format: "ogg", Data: []byte("chain")}}
	svc := NewService(client, base, WithServiceLogger(discardLogger()))
	if svc.PrimaryActive() {
		t.Fatal("PrimaryActive = true, want false")
	}
	audio, _, err := svc.TTSWithProvider(context.Background(), chineseSpeech)
	if err != nil {
		t.Fatalf("TTSWithProvider: %v", err)
	}
	if audio.Format != "ogg" || base.ttsCalls != 1 {
		t.Errorf("未启用时没有原样透传: audio=%+v calls=%d", audio, base.ttsCalls)
	}
}

// TestServiceWithoutBase 钉住"没有底链"时的诚实失败（不 panic、可分类）。
func TestServiceWithoutBase(t *testing.T) {
	svc := NewService(nil, nil, WithServiceLogger(discardLogger()))
	if _, _, err := svc.TTSWithProvider(context.Background(), "hi"); !errors.Is(err, mvoice.ErrProviderFailed) {
		t.Fatalf("err = %v, want ErrProviderFailed", err)
	}
	if _, err := svc.STT(context.Background(), mvoice.Audio{}); !errors.Is(err, mvoice.ErrProviderFailed) {
		t.Fatalf("STT err = %v, want ErrProviderFailed", err)
	}
	if _, err := svc.CloneVoice(context.Background(), "http://x", "p"); !errors.Is(err, mvoice.ErrProviderFailed) {
		t.Fatalf("CloneVoice err = %v, want ErrProviderFailed", err)
	}
}

// TestServiceDelegatesSTTAndClone 钉住"只抢合成，不抢转写/复刻"。
func TestServiceDelegatesSTTAndClone(t *testing.T) {
	client := New(Config{Enabled: true, BaseURL: "http://127.0.0.1:1"}, WithLogger(discardLogger()))
	base := &fakeChain{}
	svc := NewService(client, base, WithServiceLogger(discardLogger()))

	if text, rung, err := svc.STTWithProvider(context.Background(), mvoice.Audio{}); err != nil || text != "转写文本" || rung != "local" {
		t.Fatalf("STT 没有原样委托: text=%q rung=%q err=%v", text, rung, err)
	}
	if id, err := svc.CloneVoice(context.Background(), "http://x", "p"); err != nil || id != "voice-id" {
		t.Fatalf("CloneVoice 没有原样委托: id=%q err=%v", id, err)
	}
	if base.sttCalls != 1 || base.cloneCall != 1 {
		t.Errorf("委托次数不对: stt=%d clone=%d", base.sttCalls, base.cloneCall)
	}
}

// TestProviderAdapter 钉住"作为链的一级"这条路现在就是通的（STT 方向为 nil）。
func TestProviderAdapter(t *testing.T) {
	client := New(Config{Enabled: true, BaseURL: "http://127.0.0.1:1"}, WithLogger(discardLogger()))
	p := NewProvider(client)
	if p.Name() != ProviderName {
		t.Errorf("Name = %q, want %q", p.Name(), ProviderName)
	}
	if p.STT() != nil {
		t.Error("emotionTTS 不提供转写，STT 应为 nil")
	}
	if _, err := p.TTS().TTS(context.Background(), "   "); !errors.Is(err, ErrEmptyText) {
		t.Errorf("err = %v, want ErrEmptyText（穿透到 Client 的守卫）", err)
	}
	if _, err := NewProvider(nil).TTS().TTS(context.Background(), "hi"); !errors.Is(err, mvoice.ErrNotConfigured) {
		t.Errorf("未接线 err = %v, want ErrNotConfigured", err)
	}
}