v7.1.8

2026-06-09 06:06:52 +07:00
parent 31e9ecac35
commit 954cfe9d4f
53 changed files with 2910 additions and 912 deletions
@@ -0,0 +1,180 @@
+package backend
+
+import (
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/sha256"
+	"fmt"
+	"net/http"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+const communityDownloadPath = "/api/dl"
+
+var communityURLSeedParts = [][]byte{
+	[]byte("spotif"),
+	[]byte("lac:co"),
+	[]byte("mmunity:url:v1"),
+}
+
+var communityURLAAD = []byte("spotiflac|community|url|v1")
+
+var (
+	tidalCommunityURLNonce = []byte{
+		0x6a, 0x2a, 0x9e, 0xf3, 0x25, 0x5f, 0x48, 0x3c, 0xc3, 0xdf, 0x1d, 0xa9,
+	}
+	tidalCommunityURLCiphertext = []byte{
+		0x8f, 0x90, 0xa4, 0x28, 0x24, 0x06, 0x35, 0x13, 0x2d, 0x33, 0x96, 0x9a,
+		0xd7, 0x2c, 0x31, 0x42, 0x6a, 0xf3, 0xee, 0x86, 0x34, 0x99, 0x15, 0x1e,
+		0xa9, 0x07, 0x06, 0xe6, 0xee, 0x0d, 0x75,
+	}
+	tidalCommunityURLTag = []byte{
+		0x4d, 0x1c, 0x4e, 0x98, 0x96, 0x07, 0x16, 0xad, 0x6a, 0x7c, 0xa0, 0xdf,
+		0xe9, 0xc5, 0xf6, 0x87,
+	}
+
+	qobuzCommunityURLNonce = []byte{
+		0x5f, 0xd8, 0xfd, 0xfd, 0x89, 0x83, 0xe7, 0x6c, 0xde, 0x48, 0x47, 0x8d,
+	}
+	qobuzCommunityURLCiphertext = []byte{
+		0xfa, 0x35, 0x21, 0xba, 0x02, 0xc6, 0x15, 0x1f, 0x0e, 0xa3, 0xa6, 0x16,
+		0x64, 0x2b, 0xd8, 0xfb, 0xf5, 0x35, 0xfe, 0xe9, 0x0e, 0x59, 0xd9, 0x25,
+		0x72, 0x57, 0x88, 0x94, 0xa9, 0xb7, 0x70,
+	}
+	qobuzCommunityURLTag = []byte{
+		0xd7, 0x72, 0xb5, 0x2b, 0x1c, 0xb1, 0xfd, 0xba, 0x22, 0x09, 0x25, 0x41,
+		0x87, 0x85, 0x30, 0x1b,
+	}
+
+	amazonCommunityURLNonce = []byte{
+		0x55, 0x18, 0x01, 0x42, 0x42, 0x0c, 0xf6, 0x78, 0x8a, 0x73, 0xd7, 0x63,
+	}
+	amazonCommunityURLCiphertext = []byte{
+		0xd2, 0xf3, 0xdc, 0xe8, 0x62, 0xf0, 0xad, 0xc2, 0x4a, 0x43, 0xb1, 0xa2,
+		0x1c, 0x0d, 0x41, 0x3e, 0x2e, 0x30, 0x29, 0x5e, 0x46, 0xe2, 0xc2, 0xd6,
+		0xc1, 0xf3, 0xe3, 0x1a, 0x8f, 0x67, 0xfe,
+	}
+	amazonCommunityURLTag = []byte{
+		0xf9, 0x0a, 0xfd, 0xed, 0x9e, 0xe8, 0xb4, 0xc0, 0x75, 0xf3, 0xd5, 0x74,
+		0x3c, 0xb6, 0xa1, 0xb9,
+	}
+)
+
+var (
+	communityURLGCMOnce sync.Once
+	communityURLGCM     cipher.AEAD
+	communityURLGCMErr  error
+)
+
+func communityURLCipher() (cipher.AEAD, error) {
+	communityURLGCMOnce.Do(func() {
+		hasher := sha256.New()
+		for _, part := range communityURLSeedParts {
+			hasher.Write(part)
+		}
+		block, err := aes.NewCipher(hasher.Sum(nil))
+		if err != nil {
+			communityURLGCMErr = err
+			return
+		}
+		gcm, err := cipher.NewGCM(block)
+		if err != nil {
+			communityURLGCMErr = err
+			return
+		}
+		communityURLGCM = gcm
+	})
+	return communityURLGCM, communityURLGCMErr
+}
+
+func decryptCommunityURL(nonce, ciphertext, tag []byte) (string, error) {
+	gcm, err := communityURLCipher()
+	if err != nil {
+		return "", err
+	}
+	sealed := make([]byte, 0, len(ciphertext)+len(tag))
+	sealed = append(sealed, ciphertext...)
+	sealed = append(sealed, tag...)
+	plaintext, err := gcm.Open(nil, nonce, sealed, communityURLAAD)
+	if err != nil {
+		return "", err
+	}
+	return string(plaintext), nil
+}
+
+const communityRateLimitMaxRetries = 6
+
+const communityRateLimitFallbackWait = 30 * time.Second
+
+func GetTidalCommunityDownloadURL() string {
+	base, _ := decryptCommunityURL(tidalCommunityURLNonce, tidalCommunityURLCiphertext, tidalCommunityURLTag)
+	return base + communityDownloadPath
+}
+
+func GetQobuzCommunityDownloadURL() string {
+	base, _ := decryptCommunityURL(qobuzCommunityURLNonce, qobuzCommunityURLCiphertext, qobuzCommunityURLTag)
+	return base + communityDownloadPath
+}
+
+func GetAmazonCommunityDownloadURL() string {
+	base, _ := decryptCommunityURL(amazonCommunityURLNonce, amazonCommunityURLCiphertext, amazonCommunityURLTag)
+	return base + communityDownloadPath
+}
+
+func communityRetryAfter(resp *http.Response) time.Duration {
+	if resp == nil {
+		return communityRateLimitFallbackWait
+	}
+	if ra := strings.TrimSpace(resp.Header.Get("Retry-After")); ra != "" {
+		if secs, err := strconv.Atoi(ra); err == nil && secs >= 0 {
+			return time.Duration(secs)*time.Second + 250*time.Millisecond
+		}
+	}
+	if reset := strings.TrimSpace(resp.Header.Get("X-RateLimit-Reset")); reset != "" {
+		if epoch, err := strconv.ParseInt(reset, 10, 64); err == nil {
+			if wait := time.Until(time.Unix(epoch, 0)); wait > 0 {
+				return wait + 250*time.Millisecond
+			}
+		}
+	}
+	return communityRateLimitFallbackWait
+}
+
+func doCommunityRequest(client *http.Client, service string, reqFn func() (*http.Request, error)) (*http.Response, error) {
+	var lastErr error
+	for attempt := 0; attempt <= communityRateLimitMaxRetries; attempt++ {
+		req, err := reqFn()
+		if err != nil {
+			return nil, err
+		}
+
+		resp, err := client.Do(req)
+		if err != nil {
+			return nil, err
+		}
+
+		if resp.StatusCode != http.StatusTooManyRequests {
+			ClearRateLimitCooldown()
+			return resp, nil
+		}
+
+		wait := communityRetryAfter(resp)
+		resp.Body.Close()
+		lastErr = fmt.Errorf("%s community API rate limited (429)", service)
+
+		if attempt == communityRateLimitMaxRetries {
+			break
+		}
+		fmt.Printf("%s rate limited, waiting %.0fs before retry (%d/%d)...\n", service, wait.Seconds(), attempt+1, communityRateLimitMaxRetries)
+		SetRateLimitCooldown(wait.Seconds())
+		if sleepErr := SleepWithDownloadContext(wait); sleepErr != nil {
+			ClearRateLimitCooldown()
+			return nil, sleepErr
+		}
+		ClearRateLimitCooldown()
+	}
+	return nil, lastErr
+}