1 files changed, 94 insertions, 0 deletions
diff --git a/public/js/sample.js b/public/js/sample.js
new file mode 100644
index 0000000..d54be71
--- /dev/null
+++ b/public/js/sample.js
@@ -0,0 +1,94 @@
+/* -*- mode:javascript; coding:utf-8; -*- */
+
+'use strict';
+
+(function (window) {
+    var LOOP_COUNT = 4;
+
+    function sample(json) {
+        var x = JSON.parse(json);
+
+        this.seq = x.seq || 0;
+        this.timestamp = x.timestamp || 0;
+        this.url = x.url;
+    }
+
+    sample.prototype.gt = function (x) {
+        return this.timestamp > x.timestamp || this.timestamp === x.timestamp && this.seq > x.seq;
+    };
+
+    sample.prototype.load = function (context) {
+        var self = this;
+
+        if (self.url) {
+            var request = new XMLHttpRequest();
+
+            request.open('GET', self.url, true);
+            request.responseType = 'arraybuffer';
+
+            request.onload = function (v) {
+                if (v && v.target && v.target.status == 200) {
+                    context.decodeAudioData(request.response, function (buffer) {
+                        if (buffer) {
+                            self.buffer = buffer;
+
+                            if (self.onload) {
+                                self.onload();
+                            }
+                            console.log('sample.load: finished ', self.url);
+                        }
+                        else {
+                            console.error('sample.load: no decoded data', self);
+                        }
+                    }, function (e) {
+                        console.error('sample.load: decodeAudioData error', e, self);
+                    });
+                }
+            };
+
+            request.onerror = function (e) {
+                var s = (e && e.target && e.target.status && e.target.statusText
+                         ? (e.target.status + ' ' + e.target.statusText)
+                         : 'error');
+                console.error('sample.load: ' + s + ' while loading', self);
+            };
+
+            request.send();
+        }
+        else {
+            console.error('sample.load: no URL');
+        }
+    };
+
+    sample.prototype.play = function (context) {
+        var self = this;
+
+        if (self.buffer) {
+            var delay = self.buffer.duration * LOOP_COUNT
+            var source = context.createBufferSource();
+
+            source.buffer = self.buffer;
+            source.loop = true;
+
+            source.connect(context.destination);
+            source.start(context.currentTime);
+            source.stop(context.currentTime + delay);
+
+            window.setTimeout(function () {
+                if (self.onended) {
+                    self.onended();
+                }
+            }, delay * 1000);
+
+            // does not work
+            //source.onended = function (e) {
+            //    console.log(e);
+            //};
+        }
+        else {
+            console.error('sample.play: no buffer', self);
+        }
+    };
+
+    window['Sample'] = sample;
+})(window);