Update MiniMax music generation handling (#1522)

Co-authored-by: Octopus <kape@minimaxi.com>

internal/audio/minimax/music.go

@@ -3,6 +3,7 @@ package minimax
 import (
 	"bytes"
 	"context"
+	"encoding/hex"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -18,8 +19,8 @@ const maxMusicDownloadBytes = 200 * 1024 * 1024
 // MusicConfig configures the MiniMax music provider.
 type MusicConfig struct {
 	APIKey  string
-	APIBase string // default "https://api.minimaxi.chat/v1"
-	Model   string // default "music-2.5+"
+	APIBase string // default "https://api.minimax.io/v1"; use api.minimaxi.com for China
+	Model   string // default "music-3.0"
 }
 
 // MusicProvider generates music via the MiniMax music generation API.
@@ -34,10 +35,10 @@ type MusicProvider struct {
 // NewMusicProvider returns a MiniMax music provider.
 func NewMusicProvider(cfg MusicConfig) *MusicProvider {
 	if cfg.APIBase == "" {
-		cfg.APIBase = "https://api.minimaxi.chat/v1"
+		cfg.APIBase = "https://api.minimax.io/v1"
 	}
 	if cfg.Model == "" {
-		cfg.Model = "music-2.5+"
+		cfg.Model = "music-3.0"
 	}
 	return &MusicProvider{
 		apiKey:  cfg.APIKey,
@@ -109,8 +110,9 @@ func (p *MusicProvider) GenerateMusic(ctx context.Context, opts audio.MusicOptio
 
 	var mmResp struct {
 		Data *struct {
-			Audio string `json:"audio"`
-			Music string `json:"music"`
+			Audio  string `json:"audio"`
+			Music  string `json:"music"`
+			Status int    `json:"status"`
 		} `json:"data"`
 		BaseResp *struct {
 			StatusCode int    `json:"status_code"`
@@ -128,13 +130,28 @@ func (p *MusicProvider) GenerateMusic(ctx context.Context, opts audio.MusicOptio
 	if mmResp.Data == nil {
 		return nil, fmt.Errorf("no data in MiniMax music response")
 	}
+	if mmResp.Data.Status == 1 {
+		return nil, fmt.Errorf("MiniMax music generation is still in progress")
+	}
 
 	audioURL := mmResp.Data.Audio
 	if audioURL == "" {
 		audioURL = mmResp.Data.Music
 	}
 	if audioURL == "" {
-		return nil, fmt.Errorf("no audio URL in MiniMax music response")
+		return nil, fmt.Errorf("no audio data in MiniMax music response")
+	}
+
+	// music-3.0 may return raw audio as a hexadecimal string even when URL
+	// output is requested. Preserve URL downloads while accepting both forms.
+	if !strings.HasPrefix(audioURL, "http://") && !strings.HasPrefix(audioURL, "https://") {
+		audioBytes, err := decodeHexAudio(audioURL)
+		if err != nil {
+			return nil, fmt.Errorf("decode MiniMax music audio: %w", err)
+		}
+		return &audio.AudioResult{
+			Audio: audioBytes, Extension: "mp3", MimeType: "audio/mpeg", Model: model, Provider: "minimax",
+		}, nil
 	}
 
 	// Download the audio file from the returned URL.
@@ -167,6 +184,25 @@ func (p *MusicProvider) GenerateMusic(ctx context.Context, opts audio.MusicOptio
 	}, nil
 }
 
+func decodeHexAudio(value string) ([]byte, error) {
+	value = strings.TrimSpace(value)
+	value = strings.TrimPrefix(value, "0x")
+	if value == "" {
+		return nil, fmt.Errorf("empty hexadecimal audio payload")
+	}
+	if len(value)%2 != 0 {
+		return nil, fmt.Errorf("hexadecimal audio payload has odd length")
+	}
+	decoded, err := hex.DecodeString(value)
+	if err != nil {
+		return nil, fmt.Errorf("invalid hexadecimal audio payload: %w", err)
+	}
+	if len(decoded) > maxMusicDownloadBytes {
+		return nil, fmt.Errorf("audio response exceeds %d MB limit", maxMusicDownloadBytes/(1024*1024))
+	}
+	return decoded, nil
+}
+
 func truncate(b []byte, n int) string {
 	if len(b) <= n {
 		return string(b)

internal/audio/minimax/music_test.go

@@ -104,7 +104,7 @@ func TestMusicProvider_GenerateMusic(t *testing.T) {
 
 	t.Run("vocal_with_lyrics", func(t *testing.T) {
 		apiSrv, dlSrv := makeServers(t, map[string]any{
-			"model":            "music-2.5+",
+			"model":            "music-3.0",
 			"prompt":           "happy pop song",
 			"is_instrumental":  false,
 			"lyrics_optimizer": false,
@@ -133,6 +133,44 @@ func TestMusicProvider_GenerateMusic(t *testing.T) {
 		}
 	})
 
+	t.Run("hex_audio_payload", func(t *testing.T) {
+		apiSrv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+			_ = json.NewEncoder(w).Encode(map[string]any{
+				"data":      map[string]any{"audio": "4d503344415441", "status": 2},
+				"base_resp": map[string]any{"status_code": 0},
+			})
+		}))
+		defer apiSrv.Close()
+
+		p := NewMusicProvider(MusicConfig{APIKey: "test-key", APIBase: apiSrv.URL})
+		res, err := p.GenerateMusic(context.Background(), audio.MusicOptions{Prompt: "hex response"})
+		if err != nil {
+			t.Fatalf("unexpected error: %v", err)
+		}
+		if string(res.Audio) != "MP3DATA" {
+			t.Fatalf("audio bytes: got %q", res.Audio)
+		}
+	})
+
+	t.Run("in_progress_status", func(t *testing.T) {
+		apiSrv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			w.Header().Set("Content-Type", "application/json")
+			_ = json.NewEncoder(w).Encode(map[string]any{
+				"data":      map[string]any{"status": 1},
+				"base_resp": map[string]any{"status_code": 0},
+			})
+		}))
+		defer apiSrv.Close()
+
+		_, err := NewMusicProvider(MusicConfig{APIKey: "test-key", APIBase: apiSrv.URL}).GenerateMusic(
+			context.Background(), audio.MusicOptions{Prompt: "pending"},
+		)
+		if err == nil || !strings.Contains(err.Error(), "still in progress") {
+			t.Fatalf("expected in-progress error, got %v", err)
+		}
+	})
+
 	t.Run("instrumental_flag", func(t *testing.T) {
 		apiSrv, dlSrv := makeServers(t, map[string]any{
 			"is_instrumental": true,