Cyrene/backend/gateway/internal/handler/voice_handler.go

package handler

import (
	"bytes"
	"encoding/json"
	"io"
	"log"
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"
)

// VoiceHandler 语音处理器 — 代理到 voice-service
type VoiceHandler struct {
	voiceServiceURL string
	client          *http.Client
}

// NewVoiceHandler 创建语音处理器
func NewVoiceHandler(voiceServiceURL string) *VoiceHandler {
	return &VoiceHandler{
		voiceServiceURL: voiceServiceURL,
		client:          &http.Client{},
	}
}

// Transcribe POST /api/v1/voice/transcribe
// 代理 multipart/form-data 请求到 voice-service
func (h *VoiceHandler) Transcribe(c *gin.Context) {
	// 限制上传大小 (10MB)
	c.Request.Body = http.MaxBytesReader(c.Writer, c.Request.Body, 10<<20)

	// 读取原始请求体
	bodyBytes, err := io.ReadAll(c.Request.Body)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "读取请求体失败或文件过大，最大支持 10MB"})
		return
	}

	// 构建代理请求
	url := strings.TrimRight(h.voiceServiceURL, "/") + "/api/v1/transcribe"

	proxyReq, err := http.NewRequest("POST", url, bytes.NewReader(bodyBytes))
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "构建代理请求失败"})
		return
	}
	proxyReq.Header.Set("Content-Type", c.GetHeader("Content-Type"))

	resp, err := h.client.Do(proxyReq)
	if err != nil {
		log.Printf("[voice] Voice-Service 不可达 (Transcribe): %v", err)
		c.JSON(http.StatusBadGateway, gin.H{
			"error":     "Voice-Service 不可达: " + err.Error(),
			"errorType": "voice_service_unreachable",
			"hint":      "Voice-Service 服务未启动或不可达，请先在「服务管理」面板中启动 Voice-Service",
		})
		return
	}
	defer resp.Body.Close()

	respBody, _ := io.ReadAll(resp.Body)

	// 透传状态码和响应
	c.Data(resp.StatusCode, resp.Header.Get("Content-Type"), respBody)
}

// TTSSynthesize POST /api/v1/voice/tts
// 代理 JSON 请求到 voice-service TTS 合成
func (h *VoiceHandler) TTSSynthesize(c *gin.Context) {
	// 读取 JSON 请求体
	bodyBytes, err := io.ReadAll(c.Request.Body)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "读取请求体失败"})
		return
	}

	// 构建代理请求
	url := strings.TrimRight(h.voiceServiceURL, "/") + "/api/v1/tts/synthesize"

	proxyReq, err := http.NewRequest("POST", url, bytes.NewReader(bodyBytes))
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "构建代理请求失败"})
		return
	}
	proxyReq.Header.Set("Content-Type", "application/json")

	resp, err := h.client.Do(proxyReq)
	if err != nil {
		log.Printf("[voice] Voice-Service 不可达 (TTS): %v", err)
		c.JSON(http.StatusBadGateway, gin.H{
			"error":     "Voice-Service 不可达: " + err.Error(),
			"errorType": "voice_service_unreachable",
			"hint":      "Voice-Service 服务未启动或不可达",
		})
		return
	}
	defer resp.Body.Close()

	respBody, err := io.ReadAll(resp.Body)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "读取 Voice-Service 响应失败"})
		return
	}

	// 透传状态码、Content-Type 和响应体
	c.Data(resp.StatusCode, resp.Header.Get("Content-Type"), respBody)
}

// TTSVoices GET /api/v1/voice/tts/voices
// 代理请求到 voice-service 获取可用语音列表
func (h *VoiceHandler) TTSVoices(c *gin.Context) {
	url := strings.TrimRight(h.voiceServiceURL, "/") + "/api/v1/tts/voices"

	resp, err := h.client.Get(url)
	if err != nil {
		log.Printf("[voice] Voice-Service 不可达 (Voices): %v", err)
		c.JSON(http.StatusBadGateway, gin.H{
			"error":     "Voice-Service 不可达: " + err.Error(),
			"errorType": "voice_service_unreachable",
		})
		return
	}
	defer resp.Body.Close()

	respBody, _ := io.ReadAll(resp.Body)

	// 解析并透传
	var data interface{}
	json.Unmarshal(respBody, &data)
	c.JSON(resp.StatusCode, data)
}

// TTSStatus GET /api/v1/voice/tts/status
// 代理请求到 voice-service 获取 TTS 状态
func (h *VoiceHandler) TTSStatus(c *gin.Context) {
	url := strings.TrimRight(h.voiceServiceURL, "/") + "/api/v1/tts/status"

	resp, err := h.client.Get(url)
	if err != nil {
		log.Printf("[voice] Voice-Service 不可达 (TTS Status): %v", err)
		c.JSON(http.StatusBadGateway, gin.H{
			"error":     "Voice-Service 不可达: " + err.Error(),
			"errorType": "voice_service_unreachable",
		})
		return
	}
	defer resp.Body.Close()

	respBody, _ := io.ReadAll(resp.Body)

	var data interface{}
	json.Unmarshal(respBody, &data)
	c.JSON(resp.StatusCode, data)
}

// VoiceStatus GET /api/v1/voice/status
// 代理请求到 voice-service 获取完整状态（STT + TTS）
func (h *VoiceHandler) VoiceStatus(c *gin.Context) {
	url := strings.TrimRight(h.voiceServiceURL, "/") + "/api/v1/status"

	resp, err := h.client.Get(url)
	if err != nil {
		log.Printf("[voice] Voice-Service 不可达 (Status): %v", err)
		c.JSON(http.StatusBadGateway, gin.H{
			"error":     "Voice-Service 不可达: " + err.Error(),
			"errorType": "voice_service_unreachable",
		})
		return
	}
	defer resp.Body.Close()

	respBody, _ := io.ReadAll(resp.Body)

	var data interface{}
	json.Unmarshal(respBody, &data)
	c.JSON(resp.StatusCode, data)
}