add scrobblingt

lastfm/lastfm.go

@@ -7,7 +7,11 @@ import (
 	"fmt"
 	"net/http"
 	"net/url"
+	"sort"
+	"strconv"
 	"time"
+
+	"github.com/sentriz/gonic/db"
 )
 
 var (
@@ -18,38 +22,72 @@ var (
 )
 
 func getParamSignature(params url.Values, secret string) string {
+	// the parameters must be in order before hashing
+	paramKeys := make([]string, 0)
+	for k, _ := range params {
+		paramKeys = append(paramKeys, k)
+	}
+	sort.Strings(paramKeys)
 	toHash := ""
-	for k, v := range params {
+	for _, k := range paramKeys {
 		toHash += k
-		toHash += v[0]
+		toHash += params[k][0]
 	}
 	toHash += secret
 	hash := md5.Sum([]byte(toHash))
 	return hex.EncodeToString(hash[:])
 }
 
-func GetSession(apiKey, secret, token string) (string, error) {
-	params := url.Values{}
-	// the first 3 parameters here must be in alphabetical order
-	params.Add("api_key", apiKey)
-	params.Add("method", "auth.getSession")
-	params.Add("token", token)
-	params.Add("api_sig", getParamSignature(params, secret))
-	req, _ := http.NewRequest("GET", baseURL, nil)
+func makeRequest(method string, params url.Values) (*LastFM, error) {
+	req, _ := http.NewRequest(method, baseURL, nil)
 	req.URL.RawQuery = params.Encode()
 	resp, err := client.Do(req)
 	if err != nil {
-		return "", fmt.Errorf("error when making request to last.fm: %v", err)
+		return nil, fmt.Errorf("get: %v", err)
 	}
 	defer resp.Body.Close()
 	decoder := xml.NewDecoder(resp.Body)
 	var lastfm LastFM
 	err = decoder.Decode(&lastfm)
 	if err != nil {
-		return "", fmt.Errorf("error when decoding last.fm response: %v", err)
+		return nil, fmt.Errorf("decoding: %v", err)
 	}
 	if lastfm.Error != nil {
-		return "", fmt.Errorf("error when parsing last.fm response: %v", lastfm.Error.Value)
+		return nil, fmt.Errorf("parsing: %v", lastfm.Error.Value)
 	}
-	return lastfm.Session.Key, nil
+	return &lastfm, nil
+}
+
+func GetSession(apiKey, secret, token string) (string, error) {
+	params := url.Values{}
+	params.Add("method", "auth.getSession")
+	params.Add("api_key", apiKey)
+	params.Add("token", token)
+	params.Add("api_sig", getParamSignature(params, secret))
+	resp, err := makeRequest("GET", params)
+	if err != nil {
+		return "", fmt.Errorf("error when getting session step '%v'", err)
+	}
+	return resp.Session.Key, nil
+}
+
+func Scrobble(apiKey, secret, session string,
+	track *db.Track, stamp int, submission bool) error {
+	params := url.Values{}
+	if submission {
+		params.Add("method", "track.Scrobble")
+		params.Add("timestamp", strconv.Itoa(stamp))
+	} else {
+		params.Add("method", "track.updateNowPlaying")
+	}
+	params.Add("api_key", apiKey)
+	params.Add("sk", session)
+	params.Add("artist", track.Artist)
+	params.Add("track", track.Title)
+	params.Add("album", track.Album.Title)
+	params.Add("albumArtist", track.AlbumArtist.Name)
+	params.Add("trackNumber", strconv.Itoa(track.TrackNumber))
+	params.Add("api_sig", getParamSignature(params, secret))
+	_, err := makeRequest("POST", params)
+	return err
 }