new new

archive/archive.go

@@ -1,7 +1,7 @@
 package archive
 
 import (
-	"fmt"
+	"log"
 	"strings"
 	"io/ioutil"
 	"path/filepath"
@@ -9,7 +9,7 @@ import (
 	"../config"
 )
 
-var pln = fmt.Println
+var pln = log.Println
 
 var Archive_map map[uint32]config.Track_t
 var Archive_map_keys []uint32

playlist/playlist.go

@@ -1,7 +1,7 @@
 package playlist
 
 import (
-	"fmt"
+	"log"
 	"time"
 	"errors"
 	"strconv"
@@ -11,7 +11,7 @@ import (
 	"../config"
 )
 
-var pln = fmt.Println
+var pln = log.Println
 
 type Playlist struct {
 	NAME 		string
@@ -105,6 +105,14 @@ func (pp *PrettyPlaylist) Print() {
 	}
 }
 
+func print(slice []uint32) {
+	for i, r := range slice {
+		pln("	" + strconv.Itoa(i) + " - " + archive.Archive_map[r].NAME)
+	}
+
+}
+
+// https://github.com/golang/go/wiki/SliceTricks
 // https://stackoverflow.com/questions/33834742/remove-and-adding-elements-to-array-in-go-lang
 
 func (p *Playlist) Pop() error {
@@ -157,20 +165,54 @@ func (p *Playlist) Insert(track_id uint32, at_index int) error {
 	return nil	
 }
 
-func (p *Playlist) Delete(track_id uint32) error {
-
+func (p *Playlist) index(track_id uint32) int {
 	k := -1
-	for i := 0; i <= len(p.LIST); i++ {
+	for i := 0; i < len(p.LIST); i++ {
 		if p.LIST[i] == track_id { k = i }
 	}
+	return k	
+}
 
+func (p *Playlist) Delete(track_id uint32) error {
+	k := p.index(track_id);
+	if k < 0 {
+		return errors.New("Invalid track ID")
+	}
+	p.LIST = append(p.LIST[:k-1], p.LIST[k+1:]...)
+	return nil
+}
+
+func (p *Playlist) Move(track_id uint32, at_index int) error {
+	if at_index > p.MAX {
+		return errors.New("Invalid insert index")
+	}
+	k := p.index(track_id);
 	if k < 0 {
 		return errors.New("Invalid track ID")
 	}
 
-	p.LIST = append(p.LIST[:k-1], p.LIST[k+1:]...)
-	return nil
+	slice_head := p.LIST[:k]
+	slice_move := p.LIST[k+1:at_index+1]
+	slice_tail := make([]uint32, len(p.LIST[at_index+1:]))
+	copy(slice_tail, p.LIST[at_index+1:])
 
+	// slice_move = append(slice_move, track_id)
+
+	pln("from_index: " + strconv.Itoa(k))
+	pln("at_index: " + strconv.Itoa(at_index))
+	pln("------")
+	pln("slice head: ")
+	print(slice_head)
+	pln("slice move: ")
+	print(slice_move)
+	pln("** ")
+	pln("slice tail: ")
+	print(slice_tail)
+	pln("...........................")
+
+	p.LIST = append(slice_head, append(append(slice_move, track_id), slice_tail...)...)
+
+	return nil
 }
 
 

serve.go

@@ -13,7 +13,10 @@ var pln = fmt.Println
 
 func main() {
 	config.Loadconfig("config.ini")
-	p, _ := playlist.MakeRandom("YOYO", 10)
+	p, err := playlist.MakeRandom("YOYO", 10)
+	if err != nil {
+		panic(err)
+	}
 	p.Pop()
 	www.Init(p)
     log.Fatal(http.ListenAndServe(":8718", nil))

www/tmpl/playlist.html

@@ -48,7 +48,7 @@
   		function on_update_operation(id, index) {
   			if(sock) {
   				console.log("sending")
-  				sock.send(JSON.stringify({"op": "update", "id": id, "index": index}));	
+  				sock.send(JSON.stringify({"op": "move", "id": id, "index": index}));	
   			}  			
   		}
 	</script>	

www/www.go

@@ -2,16 +2,17 @@ package www
 
 import (
 	"log"
+	"strconv"
 	"html/template"
 	"net/http"	
-	// "golang.org/x/net/websocket"
 	"github.com/gorilla/websocket"
 	"../playlist"
 )
 
 // todo: hub - https://stackoverflow.com/questions/31532652/go-websocket-send-all-clients-a-message
 
-var pp *playlist.PrettyPlaylist
+var pp 	*playlist.PrettyPlaylist
+var p 	*playlist.Playlist
 
 var pln = log.Println
 
@@ -26,7 +27,8 @@ var upgrader = websocket.Upgrader{
     WriteBufferSize: 512,
 }
 
-func Init(p *playlist.Playlist) {
+func Init(playlist *playlist.Playlist) {
+	p = playlist
 	pp = p.Pretty() 
 	http.HandleFunc("/pp", pp_handler)
 	http.HandleFunc("/ppop", pp_operations)
@@ -59,6 +61,15 @@ func readop(c *websocket.Conn) {
 			pln(err)
 			return	//connection lost?
 		}
+
+		if opdata.OP == "move" {
+			if id, err := strconv.ParseUint(opdata.ID, 10, 32); err == nil {
+				p.Move(uint32(id), opdata.INDEX)
+				pp = p.Pretty()
+				pp.Print()		
+			}			
+		}
+
 		pln(opdata.OP)
 		pln(opdata.ID)
 		pln(opdata.INDEX)