first commit

2026-06-03 20:13:03 +00:00 · 2026-04-13 17:46:58 +02:00
commit 6e8fedf534
234 changed files with 53808 additions and 0 deletions
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+// Package songlink provides a client for the Song.link/Odesli API.
+// Song.link offers free cross-platform music URL mapping.
+package songlink
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+	"sync"
+	"time"
+)
+
+const (
+	apiBase               = "https://api.song.link/v1-alpha.1"
+	minRequestInterval    = 7 * time.Second
+	maxRequestsPerMinute  = 9
+)
+
+// PlatformLink represents a link to a track on a specific platform
+type PlatformLink struct {
+	Platform   string `json:"platform"`
+	URL        string `json:"url"`
+	EntityType string `json:"entity_type"`
+	ID         string `json:"id,omitempty"`
+	NativeURI  string `json:"native_uri,omitempty"`
+}
+
+// CrossPlatformLinks holds links for a track across multiple platforms
+type CrossPlatformLinks struct {
+	SpotifyID string                    `json:"spotify_id"`
+	ISRC      string                    `json:"isrc,omitempty"`
+	Links     map[string]PlatformLink    `json:"links"`
+}
+
+// Client for Song.link API
+type Client struct {
+	httpClient        *http.Client
+	lastRequestTime   time.Time
+	requestCount      int
+	countResetTime    time.Time
+	mu                sync.Mutex
+}
+
+// NewClient creates a new Song.link client
+func NewClient() *Client {
+	return &Client{
+		httpClient: &http.Client{
+			Timeout: 30 * time.Second,
+		},
+		countResetTime: time.Now(),
+	}
+}
+
+// Configured always returns true for Song.link (no API key needed)
+func (c *Client) Configured() bool {
+	return true
+}
+
+func (c *Client) rateLimit() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	now := time.Now()
+
+	// Reset counter every minute
+	if now.Sub(c.countResetTime) >= time.Minute {
+		c.requestCount = 0
+		c.countResetTime = now
+	}
+
+	// Check if we've hit the per-minute limit
+	if c.requestCount >= maxRequestsPerMinute {
+		waitTime := time.Minute - now.Sub(c.countResetTime)
+		if waitTime > 0 {
+			time.Sleep(waitTime)
+			c.requestCount = 0
+			c.countResetTime = time.Now()
+		}
+	}
+
+	// Ensure minimum interval between requests
+	elapsed := now.Sub(c.lastRequestTime)
+	if elapsed < minRequestInterval {
+		time.Sleep(minRequestInterval - elapsed)
+	}
+
+	c.lastRequestTime = time.Now()
+	c.requestCount++
+}
+
+// GetLinksFromSpotifyID gets cross-platform links from a Spotify track ID
+func (c *Client) GetLinksFromSpotifyID(spotifyID string) (*CrossPlatformLinks, error) {
+	spotifyURL := fmt.Sprintf("https://open.spotify.com/track/%s", spotifyID)
+	return c.GetLinks(spotifyURL)
+}
+
+// GetLinks gets cross-platform links from any music URL
+func (c *Client) GetLinks(musicURL string) (*CrossPlatformLinks, error) {
+	c.rateLimit()
+
+	params := url.Values{
+		"url": {musicURL},
+		"userCountry": {"US"},
+	}
+
+	apiURL := fmt.Sprintf("%s/links?%s", apiBase, params.Encode())
+
+	req, err := http.NewRequest("GET", apiURL, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	req.Header.Set("User-Agent", "SpotifyRecAlg/1.0")
+	req.Header.Set("Accept", "application/json")
+
+	resp, err := c.httpClient.Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == http.StatusTooManyRequests {
+		// Rate limited - wait and retry once
+		retryAfter := 15
+		if ra := resp.Header.Get("Retry-After"); ra != "" {
+			fmt.Sscanf(ra, "%d", &retryAfter)
+		}
+		time.Sleep(time.Duration(retryAfter) * time.Second)
+		return c.GetLinks(musicURL)
+	}
+
+	if resp.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("song.link API error: HTTP %d", resp.StatusCode)
+	}
+
+	var data struct {
+		EntityUniqueID string `json:"entityUniqueId"`
+		UserCountry    string `json:"userCountry"`
+		PageURL        string `json:"pageUrl"`
+		LinksByPlatform map[string]struct {
+			URL       string `json:"url"`
+			EntityUniqueID string `json:"entityUniqueId"`
+		} `json:"linksByPlatform"`
+		EntitiesByUniqueID map[string]struct {
+			ID       string `json:"id"`
+			Type     string `json:"type"`
+			Title    string `json:"title"`
+			Artist   string `json:"artistName"`
+			ThumbnailURL string `json:"thumbnailUrl"`
+			APIProvider  string `json:"apiProvider"`
+			Platforms    []string `json:"platforms"`
+		} `json:"entitiesByUniqueId"`
+	}
+
+	if err := json.NewDecoder(resp.Body).Decode(&data); err != nil {
+		return nil, err
+	}
+
+	links := &CrossPlatformLinks{
+		Links: make(map[string]PlatformLink),
+	}
+
+	// Extract Spotify ID
+	for uniqueID, entity := range data.EntitiesByUniqueID {
+		if entity.APIProvider == "spotify" {
+			links.SpotifyID = entity.ID
+		}
+		if entity.Type == "song" {
+			// ISRC can sometimes be derived from the unique ID format
+			_ = uniqueID
+		}
+	}
+
+	// Platform name mapping
+	platformNames := map[string]string{
+		"spotify":      "spotify",
+		"tidal":        "tidal",
+		"qobuz":        "qobuz",
+		"amazonMusic":  "amazonMusic",
+		"amazonStore":  "amazon",
+		"deezer":       "deezer",
+		"appleMusic":   "appleMusic",
+		"youtube":      "youtube",
+		"youtubeMusic": "youtubeMusic",
+		"soundcloud":   "soundcloud",
+		"napster":      "napster",
+		"pandora":      "pandora",
+	}
+
+	for platform, linkData := range data.LinksByPlatform {
+		if name, ok := platformNames[platform]; ok {
+			links.Links[name] = PlatformLink{
+				Platform:   platform,
+				URL:        linkData.URL,
+				EntityType: "track",
+			}
+		}
+	}
+
+	return links, nil
+}