From cd7175aec399175724f5ca7f46d9188934789afa Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 18 Feb 2016 03:53:47 -0500
Subject: [PATCH 01/41] add support for EXT-X-PROGRAM-DATE-TIME read, it's
 already support in m3u.toString

---
 parser.js | 12 ++++++++++--
 1 file changed, 10 insertions(+), 2 deletions(-)

diff --git a/parser.js b/parser.js
index d4d3f4d..4731d18 100644
--- a/parser.js
+++ b/parser.js
@@ -81,11 +81,19 @@ m3uParser.prototype['EXTINF'] = function parseInf(data) {
     this.currentItem.set('discontinuity', true);
     this.playlistDiscontinuity = false;
   }
+  if (this.playlistDate) {
+    this.currentItem.set('date', this.playlistDate);
+    this.playlistDate = null;
+  }
+};
+
+m3uParser.prototype['EXT-X-PROGRAM-DATE-TIME'] = function parseInf(data) {
+  this.playlistDate = new Date(data);
 };
 
 m3uParser.prototype['EXT-X-DISCONTINUITY'] = function parseInf() {
   this.playlistDiscontinuity = true;
-}
+};
 
 m3uParser.prototype['EXT-X-BYTERANGE'] = function parseByteRange(data) {
   this.currentItem.set('byteRange', data);
@@ -107,7 +115,7 @@ m3uParser.prototype['EXT-X-MEDIA'] = function(data) {
 
 m3uParser.prototype.parseAttributes = function parseAttributes(data) {
   data = data.split(NON_QUOTED_COMMA);
-  var self = this;
+
   return data.map(function(attribute) {
     var keyValue = attribute.split(/=(.+)/).map(function(str) {
       return str.trim();

From 05c9cda9b83041dcd5f1ec85d45ead7f0156c08e Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 18 Feb 2016 03:56:24 -0500
Subject: [PATCH 02/41] add support for slice, sliceSeconds, sliceDates, clone
 along with printing out the ENFLIST if the playlistType is not available,
 since it's optional

---
 m3u.js | 95 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 93 insertions(+), 2 deletions(-)

diff --git a/m3u.js b/m3u.js
index ce4cbd8..cffe4ba 100644
--- a/m3u.js
+++ b/m3u.js
@@ -1,3 +1,5 @@
+var util = require('util');
+
 var M3U = module.exports = function M3U() {
   this.items = {
     PlaylistItem: [],
@@ -42,7 +44,7 @@ M3U.prototype.addPlaylistItem = function addPlaylistItem(data) {
 };
 
 M3U.prototype.removePlaylistItem = function removePlaylistItem(index) {
-  if (index < this.items.PlaylistItem.length && index >= 0){
+  if (index < this.items.PlaylistItem.length && index >= 0) {
     this.items.PlaylistItem.splice(index, 1);
   } else {
     throw new RangeError('M3U PlaylistItem out of range');
@@ -89,6 +91,91 @@ M3U.prototype.merge = function merge(m3u) {
   return this;
 };
 
+M3U.prototype.slice = function slice(start, end) {
+  var m3u = this.clone();
+
+  var len = m3u.items.PlaylistItem.length;
+
+  start = !start || start < 0 ? 0 : start;
+  end = end == null || end > len ? len : end;
+
+  m3u.items.PlaylistItem = m3u.items.PlaylistItem.slice(start, end);
+
+  return m3u;
+};
+
+M3U.prototype.sliceSeconds = function slice(from, to) {
+  var start = null;
+  var end = null;
+
+  var total = 0;
+
+  if (util.isNumber(from) && util.isNumber(to) && from > to) {
+    throw 'target `to` value, if truthy, must be greater than the `from` value';
+  }
+
+  this.items.PlaylistItem.some(function(item, i) {
+    total += item.properties.duration;
+
+    if (total >= from && start == null) {
+      start = i;
+      if (to == null) {
+        return true;
+      }
+    }
+
+    if (total >= to && end == null) {
+      end = i + 1;
+      return true;
+    }
+  });
+
+  return this.slice(start, end);
+};
+
+M3U.prototype.sliceDates = function slice(from, to) {
+  var start = null;
+  var end = null;
+
+  if (!util.isDate(from) && !util.isDate(to)) {
+    throw 'sliceDates requires that at least 1 of the arguments to be a Date object';
+  }
+
+  if (util.isNumber(from)) {
+    from = new Date(to.getTime() - from * 1000);
+  } else if (util.isNumber(to)) {
+    to = new Date(from.getTime() + to * 1000);
+  }
+
+  if (util.isDate(from) && util.isDate(to) && from > to) {
+    throw 'target `to` date value, if available, must be greater than the `from` date value';
+  }
+
+  var current;
+
+  this.items.PlaylistItem.some(function(item, i) {
+    current = item.properties.date;
+
+    if (!current) {
+      throw 'Playlist segment does not have a date field, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate()';
+    }
+
+    if (current >= from && start == null) {
+      start = i;
+      if (to == null) {
+        return true;
+      }
+    }
+
+    if (current >= to && end == null) {
+      end = i + 1;
+      return true;
+    }
+  });
+
+  return this.slice(start, end);
+};
+
 M3U.prototype.toString = function toString() {
   var self   = this;
   var output = ['#EXTM3U'];
@@ -106,7 +193,7 @@ M3U.prototype.toString = function toString() {
   if (this.items.PlaylistItem.length) {
     output.push(this.items.PlaylistItem.map(itemToString).join('\n'));
 
-    if (this.get('playlistType') === 'VOD') {
+    if (this.get('playlistType') == null || this.get('playlistType') === 'VOD') {
       output.push('#EXT-X-ENDLIST');
     }
   } else {
@@ -124,6 +211,10 @@ M3U.prototype.toString = function toString() {
   return output.join('\n') + '\n';
 };
 
+M3U.prototype.clone = function clone() {
+  return M3U.unserialize(this.serialize());
+};
+
 M3U.prototype.serialize = function serialize() {
   var object = { properties: this.properties, items: {} };
   var self   = this;

From d213e213db1e03ad103b7281a1788dd52d7ff510 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 18 Feb 2016 04:00:35 -0500
Subject: [PATCH 03/41] live test should include playlistType=EVENT, since it's
 optional and if it's not there, it is assumed to be a VOD

---
 test/m3u.test.js | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/m3u.test.js b/test/m3u.test.js
index d163f7b..13df900 100644
--- a/test/m3u.test.js
+++ b/test/m3u.test.js
@@ -198,6 +198,7 @@ describe('m3u', function() {
   describe('writeLive', function() {
     it('should return a string not ending with #EXT-X-ENDLIST', function() {
       var m3u1 = getM3u();
+      m3u1.set('playlistType', 'EVENT');
       m3u1.addPlaylistItem({});
 
       var output = m3u1.toString();

From a61a689bd92ca4be3187ae702ccfaea015c73a29 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Fri, 19 Feb 2016 13:39:20 -0500
Subject: [PATCH 04/41] if you find an endlist when parsing, dont output it

---
 m3u.js    | 2 +-
 parser.js | 7 ++++++-
 2 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/m3u.js b/m3u.js
index cffe4ba..230855f 100644
--- a/m3u.js
+++ b/m3u.js
@@ -193,7 +193,7 @@ M3U.prototype.toString = function toString() {
   if (this.items.PlaylistItem.length) {
     output.push(this.items.PlaylistItem.map(itemToString).join('\n'));
 
-    if (this.get('playlistType') == null || this.get('playlistType') === 'VOD') {
+    if ((this.get('foundEndlist') && this.get('playlistType') == null) || this.get('playlistType') === 'VOD') {
       output.push('#EXT-X-ENDLIST');
     }
   } else {
diff --git a/parser.js b/parser.js
index 4731d18..cc26924 100644
--- a/parser.js
+++ b/parser.js
@@ -41,7 +41,12 @@ m3uParser.prototype.parse = function parse(line) {
     this.linesRead++;
     return true;
   }
-  if (['', '#EXT-X-ENDLIST'].indexOf(line) > -1) return true;
+
+  if (['', '#EXT-X-ENDLIST'].indexOf(line) > -1) {
+    this.m3u.set('foundEndlist', true);
+    return true;
+  }
+
   if (line.indexOf('#') == 0) {
     this.parseLine(line);
   } else {

From e9f3cca59c32893302b1f3348da97e825a5e804e Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Sat, 20 Feb 2016 02:23:33 -0500
Subject: [PATCH 05/41] add support for custom parse, i.e. set date using
 filename if the program-date-time isnt available

---
 m3u.js    | 19 ++++++++++++++++---
 parser.js | 13 ++++++++++---
 2 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/m3u.js b/m3u.js
index 230855f..730cf24 100644
--- a/m3u.js
+++ b/m3u.js
@@ -94,6 +94,10 @@ M3U.prototype.merge = function merge(m3u) {
 M3U.prototype.slice = function slice(start, end) {
   var m3u = this.clone();
 
+  if (start == null && end == null) {
+    return m3u;
+  }
+
   var len = m3u.items.PlaylistItem.length;
 
   start = !start || start < 0 ? 0 : start;
@@ -124,7 +128,7 @@ M3U.prototype.sliceSeconds = function slice(from, to) {
       }
     }
 
-    if (total >= to && end == null) {
+    if (total <= to && end == null) {
       end = i + 1;
       return true;
     }
@@ -147,6 +151,14 @@ M3U.prototype.sliceDates = function slice(from, to) {
     to = new Date(from.getTime() + to * 1000);
   }
 
+  if (!from) {
+    from = new Date(0);
+  }
+
+  if (!to) {
+    to = new Date();
+  }
+
   if (util.isDate(from) && util.isDate(to) && from > to) {
     throw 'target `to` date value, if available, must be greater than the `from` date value';
   }
@@ -167,8 +179,8 @@ M3U.prototype.sliceDates = function slice(from, to) {
       }
     }
 
-    if (current >= to && end == null) {
-      end = i + 1;
+    if (current > to && end == null) {
+      end = i;
       return true;
     }
   });
@@ -179,6 +191,7 @@ M3U.prototype.sliceDates = function slice(from, to) {
 M3U.prototype.toString = function toString() {
   var self   = this;
   var output = ['#EXTM3U'];
+
   Object.keys(this.properties).forEach(function(key) {
     var tagKey = propertyMap.findByKey(key);
     var tag = tagKey ? tagKey.tag : key;
diff --git a/parser.js b/parser.js
index cc26924..50f2c35 100644
--- a/parser.js
+++ b/parser.js
@@ -9,12 +9,14 @@ var util = require('util'),
 // used for splitting strings by commas not within double quotes
 var NON_QUOTED_COMMA = /,(?=(?:[^"]|"[^"]*")*$)/;
 
-var m3uParser = module.exports = function m3uParser() {
+var m3uParser = module.exports = function m3uParser(options) {
   ChunkedStream.apply(this, ['\n', true]);
 
   this.linesRead = 0;
   this.m3u = new M3U;
 
+  this.options = options || {};
+
   this.on('data', this.parse.bind(this));
   var self = this;
   this.on('end', function() {
@@ -26,8 +28,8 @@ util.inherits(m3uParser, ChunkedStream);
 
 m3uParser.M3U = M3U;
 
-m3uParser.createStream = function() {
-  return new m3uParser;
+m3uParser.createStream = function(options) {
+  return new m3uParser(options);
 };
 
 m3uParser.prototype.parse = function parse(line) {
@@ -54,6 +56,11 @@ m3uParser.prototype.parse = function parse(line) {
       this.addItem(new PlaylistItem);
     }
     this.currentItem.set('uri', line);
+
+    if (typeof this.options.beforeItemEmit == 'function') {
+      this.currentItem = this.options.beforeItemEmit(this.currentItem);
+    }
+
     this.emit('item', this.currentItem);
   }
   this.linesRead++;

From 298df090838b336c9e31c8abc7eb0037ebe78308 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Sat, 20 Feb 2016 02:27:14 -0500
Subject: [PATCH 06/41] gte

---
 m3u.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/m3u.js b/m3u.js
index 730cf24..1c5948d 100644
--- a/m3u.js
+++ b/m3u.js
@@ -179,7 +179,7 @@ M3U.prototype.sliceDates = function slice(from, to) {
       }
     }
 
-    if (current > to && end == null) {
+    if (current >= to && end == null) {
       end = i;
       return true;
     }

From 991825f67a8dffac3d725ba25849ee010c39ec47 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Mon, 22 Feb 2016 14:06:17 -0500
Subject: [PATCH 07/41] sliceSeconds fix

---
 m3u.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/m3u.js b/m3u.js
index 1c5948d..255cefc 100644
--- a/m3u.js
+++ b/m3u.js
@@ -101,8 +101,11 @@ M3U.prototype.slice = function slice(start, end) {
   var len = m3u.items.PlaylistItem.length;
 
   start = !start || start < 0 ? 0 : start;
-  end = end == null || end > len ? len : end;
+  if (end == null || end > len) {
+    end = len;
+  }
 
+  m3u.set('foundEndlist', true);
   m3u.items.PlaylistItem = m3u.items.PlaylistItem.slice(start, end);
 
   return m3u;
@@ -128,7 +131,7 @@ M3U.prototype.sliceSeconds = function slice(from, to) {
       }
     }
 
-    if (total <= to && end == null) {
+    if (total >= to && end == null) {
       end = i + 1;
       return true;
     }

From b0e52bcce0c8eacd427ff9202075913aaa6e0ff6 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Mon, 22 Feb 2016 14:09:44 -0500
Subject: [PATCH 08/41] comment:

---
 m3u.js | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/m3u.js b/m3u.js
index 255cefc..7adb2fb 100644
--- a/m3u.js
+++ b/m3u.js
@@ -105,7 +105,9 @@ M3U.prototype.slice = function slice(start, end) {
     end = len;
   }
 
+  // everytime you slice, the assumption here is to make the outputed playlist look like a VOD
   m3u.set('foundEndlist', true);
+
   m3u.items.PlaylistItem = m3u.items.PlaylistItem.slice(start, end);
 
   return m3u;

From 00de3ed4f6a8dbd70d6aa7eba7d818b0b96a8d9d Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Mon, 22 Feb 2016 15:05:26 -0500
Subject: [PATCH 09/41] slice fixes

---
 m3u.js | 42 ++++++++++++++++++++++++++++++++++++++----
 1 file changed, 38 insertions(+), 4 deletions(-)

diff --git a/m3u.js b/m3u.js
index 7adb2fb..9198365 100644
--- a/m3u.js
+++ b/m3u.js
@@ -123,8 +123,20 @@ M3U.prototype.sliceSeconds = function slice(from, to) {
     throw 'target `to` value, if truthy, must be greater than the `from` value';
   }
 
+  var duration = this.totalDuration();
+  if (util.isNumber(from) && from > duration) {
+    start = this.items.PlaylistItem.length;
+  }
+
+  if (util.isNumber(to) && to <= 0) {
+    end = 0;
+  }
+
+  var currentIndex = 0;
+
   this.items.PlaylistItem.some(function(item, i) {
     total += item.properties.duration;
+    currentIndex = i;
 
     if (total >= from && start == null) {
       start = i;
@@ -164,6 +176,20 @@ M3U.prototype.sliceDates = function slice(from, to) {
     to = new Date();
   }
 
+  var firstDate = ((this.items.PlaylistItem[0] || {}).properties || {}).date;
+  var lastDate = ((this.items.PlaylistItem[this.items.PlaylistItem.length - 1] || {}).properties || {}).date;
+  if (!firstDate || !lastDate) {
+    throw 'Playlist segments does look like that they have a valid date field, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate(), or set the date on your own using the beforeItemEmit hook when you setup the parser.';
+  }
+
+  if (from > lastDate) {
+    start = this.items.PlaylistItem.length;
+  }
+
+  if (to <= firstDate) {
+    end = 0;
+  }
+
   if (util.isDate(from) && util.isDate(to) && from > to) {
     throw 'target `to` date value, if available, must be greater than the `from` date value';
   }
@@ -173,10 +199,6 @@ M3U.prototype.sliceDates = function slice(from, to) {
   this.items.PlaylistItem.some(function(item, i) {
     current = item.properties.date;
 
-    if (!current) {
-      throw 'Playlist segment does not have a date field, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate()';
-    }
-
     if (current >= from && start == null) {
       start = i;
       if (to == null) {
@@ -201,6 +223,9 @@ M3U.prototype.toString = function toString() {
     var tagKey = propertyMap.findByKey(key);
     var tag = tagKey ? tagKey.tag : key;
 
+    if (ignoredProperties[key]) {
+      return;
+    }
     if (dataTypes[key] == 'boolean') {
       output.push('#' + tag);
     } else {
@@ -235,6 +260,9 @@ M3U.prototype.clone = function clone() {
 
 M3U.prototype.serialize = function serialize() {
   var object = { properties: this.properties, items: {} };
+  object.properties.totalDuration = this.totalDuration();
+  delete object.properties.foundEndlist;
+
   var self   = this;
   Object.keys(this.items).forEach(function(constructor) {
     object.items[constructor] = self.items[constructor].map(serializeItem);
@@ -245,6 +273,8 @@ M3U.prototype.serialize = function serialize() {
 M3U.unserialize = function unserialize(object) {
   var m3u = new M3U;
   m3u.properties = object.properties;
+  delete m3u.properties.totalDuration;
+
   Object.keys(object.items).forEach(function(constructor) {
     m3u.items[constructor] = object.items[constructor].map(
       Item.unserialize.bind(null, M3U[constructor])
@@ -273,6 +303,10 @@ var coerce = {
   }
 };
 
+var ignoredProperties = {
+  foundEndlist    : 1
+};
+
 var dataTypes = {
   iframesOnly    : 'boolean',
   targetDuration : 'integer',

From 1a8f4c0bc650682d05e620f84014594c64f74024 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Tue, 23 Feb 2016 13:56:31 -0500
Subject: [PATCH 10/41] deep copy when cloning

---
 m3u.js               | 38 +++++++++++++++++++++++++++-----------
 m3u/AttributeList.js |  2 +-
 m3u/Item.js          |  5 ++++-
 3 files changed, 32 insertions(+), 13 deletions(-)

diff --git a/m3u.js b/m3u.js
index 9198365..6c0d4e7 100644
--- a/m3u.js
+++ b/m3u.js
@@ -91,7 +91,7 @@ M3U.prototype.merge = function merge(m3u) {
   return this;
 };
 
-M3U.prototype.slice = function slice(start, end) {
+M3U.prototype.sliceIndex = M3U.prototype.slice = function slice(start, end) {
   var m3u = this.clone();
 
   if (start == null && end == null) {
@@ -105,8 +105,10 @@ M3U.prototype.slice = function slice(start, end) {
     end = len;
   }
 
-  // everytime you slice, the assumption here is to make the outputed playlist look like a VOD
-  m3u.set('foundEndlist', true);
+  // if live and both start & end were within the length of the stream, make it look like a VOD
+  if (! m3u.isVOD() && start < len && end < len) {
+    m3u.set('playlistType', 'VOD');
+  }
 
   m3u.items.PlaylistItem = m3u.items.PlaylistItem.slice(start, end);
 
@@ -159,6 +161,7 @@ M3U.prototype.sliceDates = function slice(from, to) {
   var end = null;
 
   if (!util.isDate(from) && !util.isDate(to)) {
+    console.log(from, to);
     throw 'sliceDates requires that at least 1 of the arguments to be a Date object';
   }
 
@@ -223,9 +226,10 @@ M3U.prototype.toString = function toString() {
     var tagKey = propertyMap.findByKey(key);
     var tag = tagKey ? tagKey.tag : key;
 
-    if (ignoredProperties[key]) {
+    if (toStringIgnoredProperties[key]) {
       return;
     }
+
     if (dataTypes[key] == 'boolean') {
       output.push('#' + tag);
     } else {
@@ -236,7 +240,7 @@ M3U.prototype.toString = function toString() {
   if (this.items.PlaylistItem.length) {
     output.push(this.items.PlaylistItem.map(itemToString).join('\n'));
 
-    if ((this.get('foundEndlist') && this.get('playlistType') == null) || this.get('playlistType') === 'VOD') {
+    if (this.isVOD()) {
       output.push('#EXT-X-ENDLIST');
     }
   } else {
@@ -254,16 +258,28 @@ M3U.prototype.toString = function toString() {
   return output.join('\n') + '\n';
 };
 
+M3U.prototype.isVOD = function clone() {
+  return this.get('foundEndlist') || this.get('playlistType') === 'VOD';
+};
+
+M3U.prototype.isLive = function clone() {
+  return !this.isVOD();
+};
+
 M3U.prototype.clone = function clone() {
   return M3U.unserialize(this.serialize());
 };
 
-M3U.prototype.serialize = function serialize() {
-  var object = { properties: this.properties, items: {} };
+M3U.prototype.toJSON = function toJSON() {
+  var object = this.serialize();
   object.properties.totalDuration = this.totalDuration();
-  delete object.properties.foundEndlist;
+  return object;
+};
 
-  var self   = this;
+M3U.prototype.serialize = function serialize() {
+  var object = { properties: JSON.parse(JSON.stringify(this.properties)), items: {} };
+
+  var self = this;
   Object.keys(this.items).forEach(function(constructor) {
     object.items[constructor] = self.items[constructor].map(serializeItem);
   });
@@ -303,8 +319,8 @@ var coerce = {
   }
 };
 
-var ignoredProperties = {
-  foundEndlist    : 1
+var toStringIgnoredProperties = {
+  foundEndlist    : true
 };
 
 var dataTypes = {
diff --git a/m3u/AttributeList.js b/m3u/AttributeList.js
index e32b6d6..ab8028e 100644
--- a/m3u/AttributeList.js
+++ b/m3u/AttributeList.js
@@ -56,7 +56,7 @@ AttributeList.prototype.toString = function toString() {
 };
 
 AttributeList.prototype.serialize = function serialize() {
-  return this.attributes;
+  return JSON.parse(JSON.stringify(this.attributes));
 };
 
 AttributeList.unserialize = function unserialize(object) {
diff --git a/m3u/Item.js b/m3u/Item.js
index 9c4f56e..41ef65b 100644
--- a/m3u/Item.js
+++ b/m3u/Item.js
@@ -31,9 +31,12 @@ Item.prototype.set = function set(key, value) {
 };
 
 Item.prototype.serialize = function serialize() {
+  var attrs = JSON.parse(JSON.stringify(this.properties));
+  attrs.date = attrs.date ? new Date(attrs.date) : attrs.date;
+
   return {
     attributes  : this.attributes.serialize(),
-    properties  : this.properties
+    properties  : attrs
   }
 };
 

From dec75e75c6ba71bc34d79d5ec137a6cab3beb0d5 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Tue, 23 Feb 2016 17:34:46 -0500
Subject: [PATCH 11/41] support lax mode, less restrictive m3u8 playlist
 parsing to enable merging a playlist with a tail of another

---
 parser.js | 13 +++++++++++--
 1 file changed, 11 insertions(+), 2 deletions(-)

diff --git a/parser.js b/parser.js
index 50f2c35..af23fb3 100644
--- a/parser.js
+++ b/parser.js
@@ -34,14 +34,23 @@ m3uParser.createStream = function(options) {
 
 m3uParser.prototype.parse = function parse(line) {
   line = line.trim();
+
   if (this.linesRead == 0) {
-    if (line != '#EXTM3U') {
+    var extm3uSkipped = false;
+
+    if (line != '#EXTM3U' && !this.options.lax) {
       return this.emit('error', new Error(
         'Non-valid M3U file. First line: ' + line
       ));
     }
+    if (line != '#EXTM3U' && this.options.lax) {
+      extm3uSkipped = true;
+    }
     this.linesRead++;
-    return true;
+
+    if (!extm3uSkipped) {
+      return true;
+    }
   }
 
   if (['', '#EXT-X-ENDLIST'].indexOf(line) > -1) {

From 42e216405394f97ccd40aa04c17000c3be57599f Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Tue, 23 Feb 2016 17:35:33 -0500
Subject: [PATCH 12/41] real unique merge support, vs the older-merge which
 behaved just like concat, also added concat ability

---
 m3u.js | 34 +++++++++++++++++++++++++++++++---
 1 file changed, 31 insertions(+), 3 deletions(-)

diff --git a/m3u.js b/m3u.js
index 6c0d4e7..a35415d 100644
--- a/m3u.js
+++ b/m3u.js
@@ -81,13 +81,41 @@ M3U.prototype.totalDuration = function totalDuration() {
   }, 0);
 };
 
-M3U.prototype.merge = function merge(m3u) {
+M3U.prototype.concat = function concat(m3u) {
   if (m3u.get('targetDuration') > this.get('targetDuration')) {
     this.set('targetDuration', m3u.get('targetDuration'));
   }
-  m3u.items.PlaylistItem[0].set('discontinuity', true);
+
+  if (m3u.items.PlaylistItem[0]) {
+    m3u.items.PlaylistItem[0].set('discontinuity', true);
+  }
+
   this.items.PlaylistItem = this.items.PlaylistItem.concat(m3u.items.PlaylistItem);
+  return this;
+};
+
+M3U.prototype.merge = function merge(m3u) {
+  var uri0 = ((m3u.items.PlaylistItem[0] || {}).properties || {}).uri;
+
+  this.concat(m3u);
+
+  var segments = this.items.PlaylistItem;
+  for(var i = 0; i < segments.length; ++i) {
+    for(var j= i + 1; j < segments.length; ++j) {
+      if(segments[i].properties.uri == segments[j].properties.uri) {
+        if (uri0 == segments[j].properties.uri) {
+          segments[i].set('discontinuity', true);
+        }
+        segments.splice(j--, 1);
+      }
+    }
+  }
+
+  if (m3u.get('foundEndlist')) {
+    this.set('foundEndlist', true);
+  }
 
+  this.items.PlaylistItem = segments;
   return this;
 };
 
@@ -293,7 +321,7 @@ M3U.unserialize = function unserialize(object) {
 
   Object.keys(object.items).forEach(function(constructor) {
     m3u.items[constructor] = object.items[constructor].map(
-      Item.unserialize.bind(null, M3U[constructor])
+        Item.unserialize.bind(null, M3U[constructor])
     );
   });
   return m3u;

From bc701ebaffd4a66c90b3bc37fa19de5433476a0a Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Wed, 24 Feb 2016 13:39:12 -0500
Subject: [PATCH 13/41] typos

---
 m3u.js | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/m3u.js b/m3u.js
index a35415d..74ccd91 100644
--- a/m3u.js
+++ b/m3u.js
@@ -119,7 +119,7 @@ M3U.prototype.merge = function merge(m3u) {
   return this;
 };
 
-M3U.prototype.sliceIndex = M3U.prototype.slice = function slice(start, end) {
+M3U.prototype.slice = M3U.prototype.sliceIndex = function slice(start, end) {
   var m3u = this.clone();
 
   if (start == null && end == null) {
@@ -286,19 +286,19 @@ M3U.prototype.toString = function toString() {
   return output.join('\n') + '\n';
 };
 
-M3U.prototype.isVOD = function clone() {
+M3U.prototype.isVOD = function isVOD () {
   return this.get('foundEndlist') || this.get('playlistType') === 'VOD';
 };
 
-M3U.prototype.isLive = function clone() {
+M3U.prototype.isLive = function isLive () {
   return !this.isVOD();
 };
 
-M3U.prototype.clone = function clone() {
+M3U.prototype.clone = function clone () {
   return M3U.unserialize(this.serialize());
 };
 
-M3U.prototype.toJSON = function toJSON() {
+M3U.prototype.toJSON = function toJSON () {
   var object = this.serialize();
   object.properties.totalDuration = this.totalDuration();
   return object;

From f743636c290381e61c88ff692d29bfba05baf24a Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 25 Feb 2016 16:05:47 -0500
Subject: [PATCH 14/41] adding tests + comments

---
 m3u.js              |   4 ++
 test/m3u.test.js    | 113 ++++++++++++++++++++++++++++++++++++++++++--
 test/parser.test.js |  69 +++++++++++++++++++++++++--
 3 files changed, 177 insertions(+), 9 deletions(-)

diff --git a/m3u.js b/m3u.js
index 74ccd91..e6c6750 100644
--- a/m3u.js
+++ b/m3u.js
@@ -81,6 +81,8 @@ M3U.prototype.totalDuration = function totalDuration() {
   }, 0);
 };
 
+
+// todo: thought: I think concat() should return a clone, not self mutate.
 M3U.prototype.concat = function concat(m3u) {
   if (m3u.get('targetDuration') > this.get('targetDuration')) {
     this.set('targetDuration', m3u.get('targetDuration'));
@@ -94,6 +96,8 @@ M3U.prototype.concat = function concat(m3u) {
   return this;
 };
 
+// todo: thought: I think merge() should return a clone, not self mutate.
+// this one would break backward compatibility though
 M3U.prototype.merge = function merge(m3u) {
   var uri0 = ((m3u.items.PlaylistItem[0] || {}).properties || {}).uri;
 
diff --git a/test/m3u.test.js b/test/m3u.test.js
index 13df900..5630056 100644
--- a/test/m3u.test.js
+++ b/test/m3u.test.js
@@ -117,8 +117,8 @@ describe('m3u', function() {
     });
   });
 
-  describe('#merge', function() {
-    it('should merge PlaylistItems from two m3us, creating a discontinuity', function() {
+  describe('#concat', function() {
+    it('should concat PlaylistItems from two m3us, creating a discontinuity', function() {
       var m3u1 = getM3u();
 
       m3u1.addPlaylistItem({});
@@ -137,6 +137,42 @@ describe('m3u', function() {
       }).length.should.eql(1);
     });
 
+    it('should use the largest targetDuration', function() {
+      var m3u1 = getM3u();
+      m3u1.set('targetDuration', 10);
+      m3u1.addPlaylistItem({});
+
+      var m3u2 = getM3u();
+      m3u2.set('targetDuration', 11);
+      m3u2.addPlaylistItem({});
+      m3u1.concat(m3u2);
+      m3u1.get('targetDuration').should.eql(11);
+    });
+  });
+
+  describe('#merge', function() {
+    it('should uniquely merge PlaylistItems from two m3us, creating a discontinuity', function() {
+      var m3u1 = getM3u();
+
+      m3u1.addPlaylistItem({uri: 'a'});
+      m3u1.addPlaylistItem({uri: 'b'});
+      m3u1.addPlaylistItem({uri: 'c'});
+
+      var m3u2 = getM3u();
+      m3u2.addPlaylistItem({uri: 'c'});
+      m3u2.addPlaylistItem({uri: 'd'});
+
+      var itemWithDiscontinuity = m3u2.items.PlaylistItem[0];
+      m3u1.merge(m3u2);
+
+      itemWithDiscontinuity.get('discontinuity').should.be.true;
+      m3u1.items.PlaylistItem.filter(function(item) {
+        return item.get('discontinuity');
+      }).length.should.eql(1);
+
+      m3u1.items.PlaylistItem.length.should.eql(4);
+    });
+
     it('should use the largest targetDuration', function() {
       var m3u1 = getM3u();
       m3u1.set('targetDuration', 10);
@@ -150,6 +186,53 @@ describe('m3u', function() {
     });
   });
 
+  describe('#slice || #sliceIndex', function() {
+    it('should slice from 1 index to another', function() {
+      var m3u1 = getM3u();
+
+      m3u1.addPlaylistItem({});
+      m3u1.addPlaylistItem({});
+      m3u1.addPlaylistItem({});
+      m3u1.addPlaylistItem({});
+
+      var m3u2 = m3u1.slice(1, 3);
+      m3u2.items.PlaylistItem.length.should.eql(2);
+
+    });
+  });
+
+  describe('#sliceSeconds', function() {
+    it('should sliceSeconds from a specific `second` to another', function() {
+      var m3u1 = getM3u();
+
+      m3u1.addPlaylistItem({duration: 5});
+      m3u1.addPlaylistItem({duration: 5});
+      m3u1.addPlaylistItem({duration: 5});
+      m3u1.addPlaylistItem({duration: 5});
+
+      var m3u2 = m3u1.sliceSeconds(5, 15);
+      m3u2.items.PlaylistItem.length.should.eql(3);
+
+    });
+  });
+
+  describe('#sliceDates', function() {
+    it('should sliceDates from a date to another', function() {
+      var m3u1 = getM3u();
+
+      var ms0 = +new Date();
+
+      m3u1.addPlaylistItem({date: new Date(ms0)});
+      m3u1.addPlaylistItem({date: new Date(ms0 + 5000)});
+      m3u1.addPlaylistItem({date: new Date(ms0 + 10000)});
+      m3u1.addPlaylistItem({date: new Date(ms0 + 15000)});
+
+      var m3u2 = m3u1.sliceDates(new Date(ms0 + 5000), new Date(ms0 + 10001));
+      m3u2.items.PlaylistItem.length.should.eql(2);
+
+    });
+  });
+
   describe('#serialize', function(done) {
     it('should return an object containing items and properties', function(done) {
       getVariantM3U(function(error, m3u) {
@@ -183,6 +266,28 @@ describe('m3u', function() {
     });
   });
 
+  describe('clone', function() {
+    it('should return a new M3U object with the same items and properties', function() {
+      var item = new M3U.PlaylistItem({ key: 'uri', value: '/path' });
+      var data = {
+        properties: {
+          targetDuration: 10
+        },
+        items: {
+          PlaylistItem: [ item.serialize() ]
+        }
+      };
+      var m3u = M3U.unserialize(data);
+      m3u.properties.should.eql(data.properties);
+      item.should.eql(m3u.items.PlaylistItem[0]);
+
+      var m3u1 = m3u.clone();
+      m3u1.properties.should.eql(data.properties);
+      item.should.eql(m3u1.items.PlaylistItem[0]);
+
+    });
+  });
+
   describe('writeVOD', function() {
     it('should return a string ending with #EXT-X-ENDLIST', function() {
       var m3u1 = getM3u();
@@ -208,9 +313,7 @@ describe('m3u', function() {
 });
 
 function getM3u() {
-  var m3u = M3U.create();
-
-  return m3u;
+  return M3U.create();
 }
 
 function getVariantM3U(callback) {
diff --git a/test/parser.test.js b/test/parser.test.js
index 4ffda67..a282e60 100644
--- a/test/parser.test.js
+++ b/test/parser.test.js
@@ -13,6 +13,54 @@ describe('parser', function() {
     parser.write('NOT VALID\n');
   });
 
+  describe('#options.lax', function() {
+    it('should forgive if #EXTM3U is not there, this is useful for mergin large and live tails of m3u8', function(done) {
+      var parser = getParser({lax: true});
+      var text = ''
+          // + '#EXTM3U\n'
+          + '#EXT-X-TARGETDURATION:10\n'
+          + '#EXT-X-VERSION:4\n'
+          + '#EXTINF:10,\n'
+          + '1.ts\n'
+          + '#EXTINF:10,\n'
+          + '2.ts\n';
+
+      parser.on('m3u', function() {
+        done();
+      });
+
+      parser.write(text);
+      parser.end();
+    });
+  });
+
+  describe('#options.beforeItemEmit', function() {
+    it('should call beforeItemEmit hook before item emit', function(done) {
+      var called = 0;
+
+      var parser = getParser({beforeItemEmit: function() {
+        called++;
+      }});
+
+      var text = ''
+          + '#EXTM3U\n'
+          + '#EXT-X-TARGETDURATION:10\n'
+          + '#EXT-X-VERSION:4\n'
+          + '#EXTINF:10,\n'
+          + '1.ts\n'
+          + '#EXTINF:10,\n'
+          + '2.ts\n';
+
+      parser.on('m3u', function() {
+        called.should.eql(2);
+        done();
+      });
+
+      parser.write(text);
+      parser.end();
+    });
+  });
+
   describe('#parseLine', function() {
     it('should call known tags', function() {
       var parser = getParser();
@@ -82,6 +130,21 @@ describe('parser', function() {
     });
   });
 
+  describe('#EXT-X-PROGRAM-DATE-TIME', function() {
+    it('should parse date value on subsequent playlist item', function() {
+      var parser = getParser();
+
+      var d = (new Date()).toISOString();
+
+      parser['EXT-X-PROGRAM-DATE-TIME'](d);
+      parser.EXTINF('4.5,some title');
+      parser.currentItem.constructor.name.should.eql('PlaylistItem');
+      parser.currentItem.get('duration').should.eql(4.5);
+      parser.currentItem.get('title').should.eql('some title');
+      parser.currentItem.get('date').toISOString().should.eql(d);
+    });
+  });
+
   describe('#EXT-X-STREAM-INF', function() {
     it('should create a new Stream item', function() {
       var parser = getParser();
@@ -126,8 +189,6 @@ describe('parser', function() {
   });
 });
 
-function getParser() {
-  var parser = m3u8.createStream();
-
-  return parser;
+function getParser(options) {
+  return m3u8.createStream(options);
 }

From 69c7db18eecfdbeb803720757b9c3746d0cc5d86 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 25 Feb 2016 16:33:50 -0500
Subject: [PATCH 15/41] 0.0.7

---
 package.json | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/package.json b/package.json
index 886673b..5d465ea 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name" : "m3u8",
-    "version" : "0.0.6",
+    "version" : "0.0.7",
     "description" : "streaming m3u8 parser for Apple's HTTP Live Streaming protocol",
     "main" : "./parser.js",
     "keywords" : [

From 4b50878c482135e0414f35448eb19e9452b7ba63 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Wed, 2 Mar 2016 20:38:45 -0500
Subject: [PATCH 16/41] mainly added m3u.mergeDates(), along with its
 dependencies m3u.sortDates(), m3u.findDateGaps() and
 m3u.insertPlaylistItemsAfter()

---
 m3u.js | 144 +++++++++++++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 139 insertions(+), 5 deletions(-)

diff --git a/m3u.js b/m3u.js
index e6c6750..19a4393 100644
--- a/m3u.js
+++ b/m3u.js
@@ -35,7 +35,6 @@ M3U.prototype.set = function setProperty(key, value) {
 
 M3U.prototype.addItem = function addItem(item) {
   this.items[item.constructor.name].push(item);
-
   return this;
 };
 
@@ -43,6 +42,31 @@ M3U.prototype.addPlaylistItem = function addPlaylistItem(data) {
   this.items.PlaylistItem.push(M3U.PlaylistItem.create(data));
 };
 
+M3U.prototype.insertPlaylistItemsAfter = function insertPlaylistItemsAfter (newItems, afterItem) {
+  var index = this.items.PlaylistItem.length;
+
+  if (!(afterItem instanceof M3U.PlaylistItem)) {
+    afterItem = M3U.PlaylistItem.create(afterItem);
+  }
+
+  newItems = [].concat(newItems).map(function(newItem) {
+    if (!(newItem instanceof M3U.PlaylistItem)) {
+      return M3U.PlaylistItem.create(newItem);
+    }
+    return newItem;
+  });
+
+  this.items.PlaylistItem.some(function(item, i) {
+    if (item.properties.uri == afterItem.properties.uri) {
+      index = i;
+      return true;
+    }
+  });
+
+  this.items.PlaylistItem = this.items.PlaylistItem.slice(0, index + 1).concat(newItems).concat(this.items.PlaylistItem.slice(index + 1));
+  return this;
+};
+
 M3U.prototype.removePlaylistItem = function removePlaylistItem(index) {
   if (index < this.items.PlaylistItem.length && index >= 0) {
     this.items.PlaylistItem.splice(index, 1);
@@ -99,11 +123,15 @@ M3U.prototype.concat = function concat(m3u) {
 // todo: thought: I think merge() should return a clone, not self mutate.
 // this one would break backward compatibility though
 M3U.prototype.merge = function merge(m3u) {
-  var uri0 = ((m3u.items.PlaylistItem[0] || {}).properties || {}).uri;
+  if (m3u.get('mediaSequence') < this.get('mediaSequence')) {
+    this.set('mediaSequence', m3u.get('mediaSequence'));
+  }
 
+  var uri0 = ((m3u.items.PlaylistItem[0] || {}).properties || {}).uri;
   this.concat(m3u);
 
   var segments = this.items.PlaylistItem;
+
   for(var i = 0; i < segments.length; ++i) {
     for(var j= i + 1; j < segments.length; ++j) {
       if(segments[i].properties.uri == segments[j].properties.uri) {
@@ -119,10 +147,96 @@ M3U.prototype.merge = function merge(m3u) {
     this.set('foundEndlist', true);
   }
 
-  this.items.PlaylistItem = segments;
   return this;
 };
 
+// todo: thought: I think mergeDates() should return a clone, not self mutate.
+M3U.prototype.mergeDates = function mergeDates (m3uB, options) {
+  options = options || {};
+
+  var clone = this.clone();
+  clone.merge(m3uB);
+  clone.sortDates();
+
+  var dateA0, dateAN, m3uPre, m3uPost;
+  if (this.items.PlaylistItem.length) {
+    dateA0 = this.items.PlaylistItem[0].get('date');
+    dateAN = this.items.PlaylistItem[this.items.PlaylistItem.length - 1].get('date');
+  }
+  m3uPre = dateA0 ? clone.sliceDates(null, new Date((+new Date(dateA0)) - 1000)) : createM3U(); // -1 sec to make it exclusive
+  m3uPost = dateAN ? clone.sliceDates(new Date((+new Date(dateAN)) + 1000)) : createM3U(); // +1 sec to make it exclusive
+
+
+  var gaps = this.findDateGaps(options);
+  gaps.forEach(function(gap) {
+    var m3u8Gap = m3uB.sliceDates(new Date(gap.starts), new Date(gap.ends));
+
+    if (m3u8Gap.items.PlaylistItem.length) {
+      m3u8Gap.items.PlaylistItem[0] && m3uPost.items.PlaylistItem[0].set('discontinuity', true);
+      gap.beforeItem.set('discontinuity', true);
+      this.insertPlaylistItemsAfter(m3u8Gap.items.PlaylistItem, gap.afterItem);
+    }
+  }.bind(this));
+
+  if (m3uPre.items.PlaylistItem.length) {
+    this.items.PlaylistItem[0] && this.items.PlaylistItem[0].set('discontinuity', true);
+  }
+
+  if (m3uPost.items.PlaylistItem.length) {
+    m3uPost.items.PlaylistItem[0].set('discontinuity', true);
+  }
+
+  this.items.PlaylistItem = m3uPre.concat(this).concat(m3uPost).items.PlaylistItem;
+
+  return this;
+};
+
+M3U.prototype.findDateGaps = function findDateGaps (options) {
+  options = options || {};
+  options.msMargin = options.msMargin == null ? 1500 : options.msMargin;
+
+  var gaps = [];
+  var segments = this.items.PlaylistItem;
+  var that = this;
+
+  segments.forEach(function(item, i) {
+    var itemNext = segments[i + 1];
+
+    var se = itemStartsEnds(item);
+    var seNext = itemStartsEnds(itemNext);
+
+    if (seNext && (seNext.starts - se.ends > options.msMargin)) {
+      var duration = (seNext.starts - se.ends) / 1000;
+      gaps.push({
+        index: i + 1,
+        starts: se.ends,
+        ends: seNext.starts,
+        duration: duration,
+        approximateMissingItems: duration / that.get('targetDuration'),
+        beforeItem: itemNext,
+        afterItem: item
+      });
+    }
+  });
+
+  return gaps;
+};
+
+M3U.prototype.sortDates = function sortDates () {
+  this.items.PlaylistItem.sort(function(playlistItem1, playlistItem2) {
+    var d1 = playlistItem1.properties.date;
+    var d2 = playlistItem2.properties.date;
+
+    if (!util.isDate(d1) || !d1 || !util.isDate(d2) || !d2) {
+      throw datesError;
+    }
+
+    return d1 < d2 ? -1 : d1 > d2 ? 1 : 0;
+  });
+  return this;
+};
+
+
 M3U.prototype.slice = M3U.prototype.sliceIndex = function slice(start, end) {
   var m3u = this.clone();
 
@@ -193,7 +307,6 @@ M3U.prototype.sliceDates = function slice(from, to) {
   var end = null;
 
   if (!util.isDate(from) && !util.isDate(to)) {
-    console.log(from, to);
     throw 'sliceDates requires that at least 1 of the arguments to be a Date object';
   }
 
@@ -213,8 +326,9 @@ M3U.prototype.sliceDates = function slice(from, to) {
 
   var firstDate = ((this.items.PlaylistItem[0] || {}).properties || {}).date;
   var lastDate = ((this.items.PlaylistItem[this.items.PlaylistItem.length - 1] || {}).properties || {}).date;
+
   if (!firstDate || !lastDate) {
-    throw 'Playlist segments does look like that they have a valid date field, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate(), or set the date on your own using the beforeItemEmit hook when you setup the parser.';
+    throw datesError;
   }
 
   if (from > lastDate) {
@@ -331,6 +445,23 @@ M3U.unserialize = function unserialize(object) {
   return m3u;
 };
 
+function itemStartsEnds(item) {
+  if (!item) {
+    return;
+  }
+
+  var date = item.get('date');
+  if (!util.isDate(date) || !date) {
+    throw datesError;
+  }
+
+  var starts = date.getTime();
+  return {
+    starts: starts,
+    ends: starts + (item.get('duration') * 1000)
+  }
+}
+
 function itemToString(item) {
   return item.toString();
 }
@@ -371,6 +502,8 @@ var propertyMap = [
   { tag: 'EXT-X-VERSION',        key: 'version' }
 ];
 
+var datesError = 'Playlist segments do not look like that they have a valid date fields, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate(), or set the date on your own using the beforeItemEmit hook when you setup the parser.';
+
 propertyMap.findByTag = function findByTag(tag) {
   return propertyMap[propertyMap.map(function(tagKey) {
     return tagKey.tag;
@@ -382,3 +515,4 @@ propertyMap.findByKey = function findByKey(key) {
     return tagKey.key;
   }).indexOf(key)];
 };
+

From 84d27ef24350770023244d57679e74deaad699dc Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 3 Mar 2016 15:44:57 -0500
Subject: [PATCH 17/41] m3u.merge() is back the way it was, to be backward
 compatible, also renamed all new functions to be more explicit, also added
 test for m3u.mergeByDate()

---
 m3u.js           | 146 +++++++++++++++++++++--------------------------
 test/m3u.test.js |  86 +++++++++++++++++++++++-----
 2 files changed, 139 insertions(+), 93 deletions(-)

diff --git a/m3u.js b/m3u.js
index 19a4393..e343b2a 100644
--- a/m3u.js
+++ b/m3u.js
@@ -105,32 +105,40 @@ M3U.prototype.totalDuration = function totalDuration() {
   }, 0);
 };
 
+M3U.prototype.concat = function concat (m3u) {
+  var clone = this.clone();
 
-// todo: thought: I think concat() should return a clone, not self mutate.
-M3U.prototype.concat = function concat(m3u) {
-  if (m3u.get('targetDuration') > this.get('targetDuration')) {
-    this.set('targetDuration', m3u.get('targetDuration'));
+  if (m3u.get('targetDuration') > clone.get('targetDuration')) {
+    clone.set('targetDuration', m3u.get('targetDuration'));
   }
 
   if (m3u.items.PlaylistItem[0]) {
     m3u.items.PlaylistItem[0].set('discontinuity', true);
   }
 
-  this.items.PlaylistItem = this.items.PlaylistItem.concat(m3u.items.PlaylistItem);
+  clone.items.PlaylistItem = clone.items.PlaylistItem.concat(m3u.items.PlaylistItem);
+
+  return clone;
+};
+
+// backward-compatible merge function, that just concats and mutates self
+// todo: remove this, since it's really a merge, it's just a concat()
+M3U.prototype.merge = function merge (m3u) {
+  var clone = this.concat(m3u);
+  this.items.PlaylistItem = clone.items.PlaylistItem;
+  this.set('targetDuration', clone.get('targetDuration'));
   return this;
 };
 
-// todo: thought: I think merge() should return a clone, not self mutate.
-// this one would break backward compatibility though
-M3U.prototype.merge = function merge(m3u) {
-  if (m3u.get('mediaSequence') < this.get('mediaSequence')) {
-    this.set('mediaSequence', m3u.get('mediaSequence'));
-  }
+M3U.prototype.mergeByUri = function mergeByUri (m3u) {
+  var clone = this.concat(m3u);
 
+  if (m3u.get('mediaSequence') < clone.get('mediaSequence')) {
+    clone.set('mediaSequence', m3u.get('mediaSequence'));
+  }
   var uri0 = ((m3u.items.PlaylistItem[0] || {}).properties || {}).uri;
-  this.concat(m3u);
 
-  var segments = this.items.PlaylistItem;
+  var segments = clone.items.PlaylistItem;
 
   for(var i = 0; i < segments.length; ++i) {
     for(var j= i + 1; j < segments.length; ++j) {
@@ -144,51 +152,47 @@ M3U.prototype.merge = function merge(m3u) {
   }
 
   if (m3u.get('foundEndlist')) {
-    this.set('foundEndlist', true);
+    clone.set('foundEndlist', true);
   }
 
-  return this;
+  return clone;
 };
 
-// todo: thought: I think mergeDates() should return a clone, not self mutate.
-M3U.prototype.mergeDates = function mergeDates (m3uB, options) {
-  options = options || {};
+M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
+  var clone = this.clone(m3u);
 
-  var clone = this.clone();
-  clone.merge(m3uB);
-  clone.sortDates();
+  options = options || {};
 
+  var len = clone.items.PlaylistItem.length;
   var dateA0, dateAN, m3uPre, m3uPost;
-  if (this.items.PlaylistItem.length) {
-    dateA0 = this.items.PlaylistItem[0].get('date');
-    dateAN = this.items.PlaylistItem[this.items.PlaylistItem.length - 1].get('date');
-  }
-  m3uPre = dateA0 ? clone.sliceDates(null, new Date((+new Date(dateA0)) - 1000)) : createM3U(); // -1 sec to make it exclusive
-  m3uPost = dateAN ? clone.sliceDates(new Date((+new Date(dateAN)) + 1000)) : createM3U(); // +1 sec to make it exclusive
 
+  if (len) {
+    dateA0 = clone.items.PlaylistItem[0].get('date');
+    dateAN = clone.items.PlaylistItem[clone.items.PlaylistItem.length - 1].get('date');
+  }
+  m3uPre = dateA0 ? m3u.sliceByDate(null, new Date((+new Date(dateA0)) - 1)) : createM3U(); // -1 ms to make it exclusive
+  m3uPost = dateAN ? m3u.sliceByDate(new Date((+new Date(dateAN)) + 1)) : createM3U(); // +1 ms to make it exclusive
 
-  var gaps = this.findDateGaps(options);
+  var gaps = clone.findDateGaps(options);
   gaps.forEach(function(gap) {
-    var m3u8Gap = m3uB.sliceDates(new Date(gap.starts), new Date(gap.ends));
+    var m3u8Gap = m3u.sliceByDate(new Date(gap.starts), new Date(gap.ends));
 
     if (m3u8Gap.items.PlaylistItem.length) {
       m3u8Gap.items.PlaylistItem[0] && m3uPost.items.PlaylistItem[0].set('discontinuity', true);
       gap.beforeItem.set('discontinuity', true);
-      this.insertPlaylistItemsAfter(m3u8Gap.items.PlaylistItem, gap.afterItem);
+      clone.insertPlaylistItemsAfter(m3u8Gap.items.PlaylistItem, gap.afterItem);
     }
-  }.bind(this));
+  });
 
   if (m3uPre.items.PlaylistItem.length) {
-    this.items.PlaylistItem[0] && this.items.PlaylistItem[0].set('discontinuity', true);
+    clone.items.PlaylistItem[0] && clone.items.PlaylistItem[0].set('discontinuity', true);
   }
 
   if (m3uPost.items.PlaylistItem.length) {
     m3uPost.items.PlaylistItem[0].set('discontinuity', true);
   }
 
-  this.items.PlaylistItem = m3uPre.concat(this).concat(m3uPost).items.PlaylistItem;
-
-  return this;
+  return m3uPre.concat(clone).concat(m3uPost)
 };
 
 M3U.prototype.findDateGaps = function findDateGaps (options) {
@@ -222,22 +226,7 @@ M3U.prototype.findDateGaps = function findDateGaps (options) {
   return gaps;
 };
 
-M3U.prototype.sortDates = function sortDates () {
-  this.items.PlaylistItem.sort(function(playlistItem1, playlistItem2) {
-    var d1 = playlistItem1.properties.date;
-    var d2 = playlistItem2.properties.date;
-
-    if (!util.isDate(d1) || !d1 || !util.isDate(d2) || !d2) {
-      throw datesError;
-    }
-
-    return d1 < d2 ? -1 : d1 > d2 ? 1 : 0;
-  });
-  return this;
-};
-
-
-M3U.prototype.slice = M3U.prototype.sliceIndex = function slice(start, end) {
+M3U.prototype.sliceByIndex = M3U.prototype.slice = function sliceByIndex (start, end) {
   var m3u = this.clone();
 
   if (start == null && end == null) {
@@ -261,7 +250,7 @@ M3U.prototype.slice = M3U.prototype.sliceIndex = function slice(start, end) {
   return m3u;
 };
 
-M3U.prototype.sliceSeconds = function slice(from, to) {
+M3U.prototype.sliceBySeconds = function sliceBySeconds (from, to) {
   var start = null;
   var end = null;
 
@@ -299,15 +288,15 @@ M3U.prototype.sliceSeconds = function slice(from, to) {
     }
   });
 
-  return this.slice(start, end);
+  return this.sliceByIndex(start, end);
 };
 
-M3U.prototype.sliceDates = function slice(from, to) {
+M3U.prototype.sliceByDate = function sliceByDate (from, to) {
   var start = null;
   var end = null;
 
   if (!util.isDate(from) && !util.isDate(to)) {
-    throw 'sliceDates requires that at least 1 of the arguments to be a Date object';
+    throw new Error('at least 1 of the arguments needs to be a Date object');
   }
 
   if (util.isNumber(from)) {
@@ -316,19 +305,19 @@ M3U.prototype.sliceDates = function slice(from, to) {
     to = new Date(from.getTime() + to * 1000);
   }
 
+  var firstDate = ((this.items.PlaylistItem[0] || {}).properties || {}).date;
+  var lastDate = ((this.items.PlaylistItem[this.items.PlaylistItem.length - 1] || {}).properties || {}).date;
+
+  if (!firstDate || !lastDate) {
+    throw new Error('Playlist segments do not look like that they have a valid date fields, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate(), or set the date on your own using the beforeItemEmit hook when you setup the parser.');
+  }
+
   if (!from) {
     from = new Date(0);
   }
 
   if (!to) {
-    to = new Date();
-  }
-
-  var firstDate = ((this.items.PlaylistItem[0] || {}).properties || {}).date;
-  var lastDate = ((this.items.PlaylistItem[this.items.PlaylistItem.length - 1] || {}).properties || {}).date;
-
-  if (!firstDate || !lastDate) {
-    throw datesError;
+    to = new Date(lastDate.getTime() + 1);
   }
 
   if (from > lastDate) {
@@ -340,7 +329,7 @@ M3U.prototype.sliceDates = function slice(from, to) {
   }
 
   if (util.isDate(from) && util.isDate(to) && from > to) {
-    throw 'target `to` date value, if available, must be greater than the `from` date value';
+    throw new Error('target `to` date value, if available, must be greater than the `from` date value');
   }
 
   var current;
@@ -361,10 +350,10 @@ M3U.prototype.sliceDates = function slice(from, to) {
     }
   });
 
-  return this.slice(start, end);
+  return this.sliceByIndex(start, end);
 };
 
-M3U.prototype.toString = function toString() {
+M3U.prototype.toString = function toString () {
   var self   = this;
   var output = ['#EXTM3U'];
 
@@ -422,7 +411,7 @@ M3U.prototype.toJSON = function toJSON () {
   return object;
 };
 
-M3U.prototype.serialize = function serialize() {
+M3U.prototype.serialize = function serialize () {
   var object = { properties: JSON.parse(JSON.stringify(this.properties)), items: {} };
 
   var self = this;
@@ -432,7 +421,7 @@ M3U.prototype.serialize = function serialize() {
   return object;
 };
 
-M3U.unserialize = function unserialize(object) {
+M3U.unserialize = function unserialize (object) {
   var m3u = new M3U;
   m3u.properties = object.properties;
   delete m3u.properties.totalDuration;
@@ -445,14 +434,14 @@ M3U.unserialize = function unserialize(object) {
   return m3u;
 };
 
-function itemStartsEnds(item) {
+function itemStartsEnds (item) {
   if (!item) {
     return;
   }
 
   var date = item.get('date');
   if (!util.isDate(date) || !date) {
-    throw datesError;
+    throw new Error('Playlist segments do not look like that they have a valid date fields, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate(), or set the date on your own using the beforeItemEmit hook when you setup the parser.');
   }
 
   var starts = date.getTime();
@@ -462,22 +451,22 @@ function itemStartsEnds(item) {
   }
 }
 
-function itemToString(item) {
+function itemToString (item) {
   return item.toString();
 }
 
-function serializeItem(item) {
+function serializeItem (item) {
   return item.serialize();
 }
 
 var coerce = {
-  boolean: function coerceBoolean(value) {
+  boolean: function coerceBoolean (value) {
     return true;
   },
-  integer: function coerceInteger(value) {
+  integer: function coerceInteger (value) {
     return parseInt(value, 10);
   },
-  unknown: function coerceUnknown(value) {
+  unknown: function coerceUnknown (value) {
     return value;
   }
 };
@@ -502,17 +491,14 @@ var propertyMap = [
   { tag: 'EXT-X-VERSION',        key: 'version' }
 ];
 
-var datesError = 'Playlist segments do not look like that they have a valid date fields, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate(), or set the date on your own using the beforeItemEmit hook when you setup the parser.';
-
-propertyMap.findByTag = function findByTag(tag) {
+propertyMap.findByTag = function findByTag (tag) {
   return propertyMap[propertyMap.map(function(tagKey) {
     return tagKey.tag;
   }).indexOf(tag)];
 };
 
-propertyMap.findByKey = function findByKey(key) {
+propertyMap.findByKey = function findByKey (key) {
   return propertyMap[propertyMap.map(function(tagKey) {
     return tagKey.key;
   }).indexOf(key)];
 };
-
diff --git a/test/m3u.test.js b/test/m3u.test.js
index 5630056..9de0ef3 100644
--- a/test/m3u.test.js
+++ b/test/m3u.test.js
@@ -4,6 +4,7 @@ var fs     = require('fs'),
     should = require('should');
 
 describe('m3u', function() {
+
   describe('#set', function() {
     it('should set property on m3u', function() {
       var m3u = getM3u();
@@ -118,7 +119,7 @@ describe('m3u', function() {
   });
 
   describe('#concat', function() {
-    it('should concat PlaylistItems from two m3us, creating a discontinuity', function() {
+    it('should concat PlaylistItems from two m3us and return a new m3u, creating a discontinuity', function() {
       var m3u1 = getM3u();
 
       m3u1.addPlaylistItem({});
@@ -130,7 +131,7 @@ describe('m3u', function() {
       m3u2.addPlaylistItem({});
 
       var itemWithDiscontinuity = m3u2.items.PlaylistItem[0];
-      m3u1.merge(m3u2);
+      m3u1 = m3u1.merge(m3u2);
       itemWithDiscontinuity.get('discontinuity').should.be.true;
       m3u1.items.PlaylistItem.filter(function(item) {
         return item.get('discontinuity');
@@ -145,13 +146,13 @@ describe('m3u', function() {
       var m3u2 = getM3u();
       m3u2.set('targetDuration', 11);
       m3u2.addPlaylistItem({});
-      m3u1.concat(m3u2);
+      m3u1 = m3u1.concat(m3u2);
       m3u1.get('targetDuration').should.eql(11);
     });
   });
 
   describe('#merge', function() {
-    it('should uniquely merge PlaylistItems from two m3us, creating a discontinuity', function() {
+    it('should just merge (as in concat) PlaylistItems from two m3us by self mutating the current m3u, creating a discontinuity', function() {
       var m3u1 = getM3u();
 
       m3u1.addPlaylistItem({uri: 'a'});
@@ -170,7 +171,7 @@ describe('m3u', function() {
         return item.get('discontinuity');
       }).length.should.eql(1);
 
-      m3u1.items.PlaylistItem.length.should.eql(4);
+      m3u1.items.PlaylistItem.length.should.eql(5);
     });
 
     it('should use the largest targetDuration', function() {
@@ -186,7 +187,66 @@ describe('m3u', function() {
     });
   });
 
-  describe('#slice || #sliceIndex', function() {
+  describe('#mergeByUri', function() {
+    it('should uniquely merge PlaylistItems from two m3us using URIs, creating a discontinuity', function() {
+      var m3u1 = getM3u();
+
+      m3u1.addPlaylistItem({uri: 'a'});
+      m3u1.addPlaylistItem({uri: 'b'});
+      m3u1.addPlaylistItem({uri: 'c'});
+
+      var m3u2 = getM3u();
+      m3u2.addPlaylistItem({uri: 'c'});
+      m3u2.addPlaylistItem({uri: 'd'});
+
+      var itemWithDiscontinuity = m3u2.items.PlaylistItem[0];
+      m3u1 = m3u1.mergeByUri(m3u2);
+
+      itemWithDiscontinuity.get('discontinuity').should.be.true;
+      m3u1.items.PlaylistItem.filter(function(item) {
+        return item.get('discontinuity');
+      }).length.should.eql(1);
+
+      m3u1.items.PlaylistItem.length.should.eql(4);
+    });
+  });
+
+  describe('#mergeByDate', function() {
+    it('should uniquely merge PlaylistItems from two m3us using Dates, creating some discontinuities', function() {
+      var m3u1 = getM3u();
+      var ms0 = +new Date() - (24 * 60 * 60 * 1000);
+
+      m3u1.addPlaylistItem({uri: 'a.3', date: new Date(ms0)});
+      m3u1.addPlaylistItem({uri: 'a.4', date: new Date(ms0 + 10000)});
+      m3u1.addPlaylistItem({uri: 'a.6', date: new Date(ms0 + 30000)});
+
+      var m3u2 = getM3u();
+      m3u2.addPlaylistItem({uri: 'b.1', date: new Date(ms0 - 20000)});
+      m3u2.addPlaylistItem({uri: 'b.2', date: new Date(ms0 - 10000)});
+      m3u2.addPlaylistItem({uri: 'b.5', date: new Date(ms0 + 20000)});
+      m3u2.addPlaylistItem({uri: 'b.6', date: new Date(ms0 + 30000)});
+      m3u2.addPlaylistItem({uri: 'b.7', date: new Date(ms0 + 40000)});
+
+      m3u1 = m3u1.mergeByDate(m3u2);
+
+      m3u1.items.PlaylistItem.length.should.eql(7);
+
+      m3u1.items.PlaylistItem[0].get('uri').should.be.eql('b.1');
+      m3u1.items.PlaylistItem[1].get('uri').should.be.eql('b.2');
+      m3u1.items.PlaylistItem[2].get('uri').should.be.eql('a.3');
+      m3u1.items.PlaylistItem[3].get('uri').should.be.eql('a.4');
+      m3u1.items.PlaylistItem[4].get('uri').should.be.eql('b.5');
+      m3u1.items.PlaylistItem[5].get('uri').should.be.eql('a.6');
+      m3u1.items.PlaylistItem[6].get('uri').should.be.eql('b.7');
+
+      m3u1.items.PlaylistItem[2].get('discontinuity').should.be.true;
+//      m3u1.items.PlaylistItem[4].get('discontinuity').should.be.true;
+      m3u1.items.PlaylistItem[5].get('discontinuity').should.be.true;
+      m3u1.items.PlaylistItem[6].get('discontinuity').should.be.true;
+    });
+  });
+
+  describe('#sliceByIndex', function() {
     it('should slice from 1 index to another', function() {
       var m3u1 = getM3u();
 
@@ -195,14 +255,14 @@ describe('m3u', function() {
       m3u1.addPlaylistItem({});
       m3u1.addPlaylistItem({});
 
-      var m3u2 = m3u1.slice(1, 3);
+      var m3u2 = m3u1.sliceByIndex(1, 3);
       m3u2.items.PlaylistItem.length.should.eql(2);
 
     });
   });
 
-  describe('#sliceSeconds', function() {
-    it('should sliceSeconds from a specific `second` to another', function() {
+  describe('#sliceBySeconds', function() {
+    it('should sliceBySeconds from a specific `second` to another', function() {
       var m3u1 = getM3u();
 
       m3u1.addPlaylistItem({duration: 5});
@@ -210,14 +270,14 @@ describe('m3u', function() {
       m3u1.addPlaylistItem({duration: 5});
       m3u1.addPlaylistItem({duration: 5});
 
-      var m3u2 = m3u1.sliceSeconds(5, 15);
+      var m3u2 = m3u1.sliceBySeconds(5, 15);
       m3u2.items.PlaylistItem.length.should.eql(3);
 
     });
   });
 
-  describe('#sliceDates', function() {
-    it('should sliceDates from a date to another', function() {
+  describe('#sliceByDate', function() {
+    it('should sliceByDate from a date to another', function() {
       var m3u1 = getM3u();
 
       var ms0 = +new Date();
@@ -227,7 +287,7 @@ describe('m3u', function() {
       m3u1.addPlaylistItem({date: new Date(ms0 + 10000)});
       m3u1.addPlaylistItem({date: new Date(ms0 + 15000)});
 
-      var m3u2 = m3u1.sliceDates(new Date(ms0 + 5000), new Date(ms0 + 10001));
+      var m3u2 = m3u1.sliceByDate(new Date(ms0 + 5000), new Date(ms0 + 10001));
       m3u2.items.PlaylistItem.length.should.eql(2);
 
     });

From 2792d1bc9aec4e41c06a37e2d52135ffe419a036 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 3 Mar 2016 16:01:11 -0500
Subject: [PATCH 18/41] discontinuity bug fix

---
 m3u.js           | 2 +-
 test/m3u.test.js | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/m3u.js b/m3u.js
index e343b2a..8d85cef 100644
--- a/m3u.js
+++ b/m3u.js
@@ -178,7 +178,7 @@ M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
     var m3u8Gap = m3u.sliceByDate(new Date(gap.starts), new Date(gap.ends));
 
     if (m3u8Gap.items.PlaylistItem.length) {
-      m3u8Gap.items.PlaylistItem[0] && m3uPost.items.PlaylistItem[0].set('discontinuity', true);
+      m3u8Gap.items.PlaylistItem[0] && m3u8Gap.items.PlaylistItem[0].set('discontinuity', true);
       gap.beforeItem.set('discontinuity', true);
       clone.insertPlaylistItemsAfter(m3u8Gap.items.PlaylistItem, gap.afterItem);
     }
diff --git a/test/m3u.test.js b/test/m3u.test.js
index 9de0ef3..2b3053c 100644
--- a/test/m3u.test.js
+++ b/test/m3u.test.js
@@ -240,7 +240,7 @@ describe('m3u', function() {
       m3u1.items.PlaylistItem[6].get('uri').should.be.eql('b.7');
 
       m3u1.items.PlaylistItem[2].get('discontinuity').should.be.true;
-//      m3u1.items.PlaylistItem[4].get('discontinuity').should.be.true;
+      m3u1.items.PlaylistItem[4].get('discontinuity').should.be.true;
       m3u1.items.PlaylistItem[5].get('discontinuity').should.be.true;
       m3u1.items.PlaylistItem[6].get('discontinuity').should.be.true;
     });

From e9f56c2bb2dff909e3dd6b58225c45833baa028d Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 3 Mar 2016 16:02:42 -0500
Subject: [PATCH 19/41] var name

---
 m3u.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/m3u.js b/m3u.js
index 8d85cef..ea30ed6 100644
--- a/m3u.js
+++ b/m3u.js
@@ -175,12 +175,12 @@ M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
 
   var gaps = clone.findDateGaps(options);
   gaps.forEach(function(gap) {
-    var m3u8Gap = m3u.sliceByDate(new Date(gap.starts), new Date(gap.ends));
+    var m3uGap = m3u.sliceByDate(new Date(gap.starts), new Date(gap.ends));
 
-    if (m3u8Gap.items.PlaylistItem.length) {
-      m3u8Gap.items.PlaylistItem[0] && m3u8Gap.items.PlaylistItem[0].set('discontinuity', true);
+    if (m3uGap.items.PlaylistItem.length) {
+      m3uGap.items.PlaylistItem[0] && m3uGap.items.PlaylistItem[0].set('discontinuity', true);
       gap.beforeItem.set('discontinuity', true);
-      clone.insertPlaylistItemsAfter(m3u8Gap.items.PlaylistItem, gap.afterItem);
+      clone.insertPlaylistItemsAfter(m3uGap.items.PlaylistItem, gap.afterItem);
     }
   });
 

From 49b87095d522f09cb085204a03d3f6fae8769c16 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 3 Mar 2016 17:04:23 -0500
Subject: [PATCH 20/41] fix vod state after mergeByDate

---
 m3u.js | 11 ++++++++++-
 1 file changed, 10 insertions(+), 1 deletion(-)

diff --git a/m3u.js b/m3u.js
index ea30ed6..fc6cce6 100644
--- a/m3u.js
+++ b/m3u.js
@@ -192,7 +192,16 @@ M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
     m3uPost.items.PlaylistItem[0].set('discontinuity', true);
   }
 
-  return m3uPre.concat(clone).concat(m3uPost)
+  var result = m3uPre.concat(clone).concat(m3uPost);
+
+  var m3uTail = m3uPost.items.PlaylistItem.length ? m3uPost : clone.items.PlaylistItem.length ? clone : m3uPre;
+  if (m3uTail.isVOD()) {
+    result.set('playlistType', 'VOD');
+  } else {
+    result.set('playlistType', 'EVENT');
+  }
+
+  return result;
 };
 
 M3U.prototype.findDateGaps = function findDateGaps (options) {

From 3ba7418177fe9a3b69dca700f1800f58e8bb88c8 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Fri, 4 Mar 2016 17:31:11 -0500
Subject: [PATCH 21/41] added m3u.sortByDate(), m3u.sortByUri(),
 m3u.isDateSupported(), fixed minor date slicing bug

---
 m3u.js | 40 +++++++++++++++++++++++++++++++++++++++-
 1 file changed, 39 insertions(+), 1 deletion(-)

diff --git a/m3u.js b/m3u.js
index fc6cce6..03f9028 100644
--- a/m3u.js
+++ b/m3u.js
@@ -204,6 +204,38 @@ M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
   return result;
 };
 
+M3U.prototype.sortByDate = function sortByDate () {
+  if (! this.isDateSupported()) {
+    return this;
+  }
+
+  this.items.PlaylistItem.sort(function(playlistItem1, playlistItem2) {
+    var d1 = playlistItem1.properties.date;
+    var d2 = playlistItem2.properties.date;
+
+    return d1 < d2 ? -1 : d1 > d2 ? 1 : 0;
+  });
+
+  return this;
+};
+
+M3U.prototype.sortByUri = function sortByUri (options) {
+  options = options || {};
+
+  this.items.PlaylistItem.sort(function(playlistItem1, playlistItem2) {
+    var u1 = playlistItem1.properties.uri;
+    var u2 = playlistItem2.properties.uri;
+
+    if (!options.useFullPath) {
+      u1 = u1.split('/').pop();
+      u2 = u2.split('/').pop();
+    }
+
+    return u1 < u2 ? -1 : u1 > u2 ? 1 : 0;
+  });
+  return this;
+};
+
 M3U.prototype.findDateGaps = function findDateGaps (options) {
   options = options || {};
   options.msMargin = options.msMargin == null ? 1500 : options.msMargin;
@@ -322,7 +354,7 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
   }
 
   if (!from) {
-    from = new Date(0);
+    from = new Date(firstDate.getTime() - 1);
   }
 
   if (!to) {
@@ -402,6 +434,12 @@ M3U.prototype.toString = function toString () {
   return output.join('\n') + '\n';
 };
 
+
+M3U.prototype.isDateSupported = function isDateSupported () {
+  var date = ((this.items.PlaylistItem[0] || {}).properties || {}).date;
+  return date ? util.isDate(date) : undefined;
+};
+
 M3U.prototype.isVOD = function isVOD () {
   return this.get('foundEndlist') || this.get('playlistType') === 'VOD';
 };

From dabc7e24775b5928b128e24d9add53b73b14e1db Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Tue, 8 Mar 2016 16:13:44 -0500
Subject: [PATCH 22/41] date check, only if dates were passed in

---
 m3u.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/m3u.js b/m3u.js
index 03f9028..23777ab 100644
--- a/m3u.js
+++ b/m3u.js
@@ -353,6 +353,10 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
     throw new Error('Playlist segments do not look like that they have a valid date fields, you must specify EXT-X-PROGRAM-DATE-TIME for each segment in order to sliceDate(), or set the date on your own using the beforeItemEmit hook when you setup the parser.');
   }
 
+  if (util.isDate(from) && util.isDate(to) && from > to) {
+    throw new Error('target `to` date value, if available, must be greater than the `from` date value');
+  }
+
   if (!from) {
     from = new Date(firstDate.getTime() - 1);
   }
@@ -369,10 +373,6 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
     end = 0;
   }
 
-  if (util.isDate(from) && util.isDate(to) && from > to) {
-    throw new Error('target `to` date value, if available, must be greater than the `from` date value');
-  }
-
   var current;
 
   this.items.PlaylistItem.some(function(item, i) {

From 3446a73696e7d4024f2ecd40b795705e8de16f98 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Wed, 23 Mar 2016 18:10:14 -0400
Subject: [PATCH 23/41] covering  slicing edge cases, 1 end slice

---
 m3u.js | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/m3u.js b/m3u.js
index 23777ab..bcfe5f1 100644
--- a/m3u.js
+++ b/m3u.js
@@ -316,14 +316,14 @@ M3U.prototype.sliceBySeconds = function sliceBySeconds (from, to) {
     total += item.properties.duration;
     currentIndex = i;
 
-    if (total >= from && start == null) {
+    if (from != null && total >= from && start == null) {
       start = i;
       if (to == null) {
         return true;
       }
     }
 
-    if (total >= to && end == null) {
+    if (to != null && total >= to && end == null) {
       end = i + 1;
       return true;
     }
@@ -378,14 +378,14 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
   this.items.PlaylistItem.some(function(item, i) {
     current = item.properties.date;
 
-    if (current >= from && start == null) {
+    if (from != null && current >= from && start == null) {
       start = i;
       if (to == null) {
         return true;
       }
     }
 
-    if (current >= to && end == null) {
+    if (to != null && current >= to && end == null) {
       end = i;
       return true;
     }

From d7e73f3e9cfff119b48ff3970335996a79049693 Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Thu, 7 Apr 2016 14:35:50 -0400
Subject: [PATCH 24/41] support NodeJS 0.10 and add rangeBounds checkers

---
 .editorConfig |  0
 m3u.js        | 91 ++++++++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 90 insertions(+), 1 deletion(-)
 create mode 100644 .editorConfig

diff --git a/.editorConfig b/.editorConfig
new file mode 100644
index 0000000..e69de29
diff --git a/m3u.js b/m3u.js
index bcfe5f1..944f19b 100644
--- a/m3u.js
+++ b/m3u.js
@@ -1,4 +1,17 @@
-var util = require('util');
+var util;
+try {
+  util = require('util');
+} catch(e) {
+  util = {};
+}
+
+util.isNumber = util.isNumber || function (n) {
+  return !isNaN(parseFloat(n)) && isFinite(n);
+};
+
+util.isDate = util.isDate || function (d) {
+  return d instanceof Date && !isNaN(d.valueOf());
+};
 
 var M3U = module.exports = function M3U() {
   this.items = {
@@ -394,6 +407,82 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
   return this.sliceByIndex(start, end);
 };
 
+M3U.prototype.isRangeWithinIndexBounds = function isRangeWithinSecondsBounds (from, to) {
+
+  var len = this.items.PlaylistItem.length;
+
+  if (!len) {
+    return false;
+  }
+
+  var left = true;
+  var right = true;
+
+  if (from != null) {
+    left = !!this.items.PlaylistItem[from];
+  }
+
+  if (to != null) {
+    right = !!this.items.PlaylistItem[to];
+  }
+
+  return left && right;
+};
+
+M3U.prototype.isRangeWithinSecondsBounds = function isRangeWithinSecondsBounds (from, to) {
+
+  var len = this.items.PlaylistItem.length;
+
+  if (!len) {
+    return false;
+  }
+
+  var left = true;
+  var right = true;
+
+  if (from != null) {
+    left = 0 <= from;
+  }
+
+  if (to != null) {
+    right = to <= this.totalDuration();
+  }
+
+  return left && right;
+};
+
+M3U.prototype.isRangeWithinDateBounds = function isRangeWithinDateBounds (from, to) {
+
+  if (!util.isDate(from) && !util.isDate(to)) {
+    throw new Error('at least 1 of the arguments needs to be a Date object');
+  }
+
+  if (util.isNumber(from)) {
+    from = new Date(to.getTime() - from * 1000);
+  } else if (util.isNumber(to)) {
+    to = new Date(from.getTime() + to * 1000);
+  }
+
+  var len = this.items.PlaylistItem.length;
+
+  if (!len) {
+    return false;
+  }
+
+  var left = true;
+  var right = true;
+
+  if (from != null) {
+    left = this.items.PlaylistItem[0].properties.date <= from;
+  }
+
+  if (to != null) {
+    right = to <= this.items.PlaylistItem[len - 1].properties.date;
+  }
+
+  return left && right;
+};
+
 M3U.prototype.toString = function toString () {
   var self   = this;
   var output = ['#EXTM3U'];

From d09dd57c14325947a6de5a109d8b9725062b7b35 Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Thu, 7 Apr 2016 14:36:14 -0400
Subject: [PATCH 25/41] project tidy files

---
 .gitignore | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/.gitignore b/.gitignore
index 3c3629e..db906bb 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,37 @@
+.idea
+.DS_Store
+
+# Logs
+logs
+*.log
+npm-debug.log*
+
+# Runtime data
+pids
+*.pid
+*.seed
+
+# Directory for instrumented libs generated by jscoverage/JSCover
+lib-cov
+
+# Coverage directory used by tools like istanbul
+coverage
+
+# Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
+.grunt
+
+# node-waf configuration
+.lock-wscript
+
+# Compiled binary addons (http://nodejs.org/api/addons.html)
+build/Release
+
+# Dependency directories
 node_modules
+jspm_packages
+
+# Optional npm cache directory
+.npm
+
+# Optional REPL history
+.node_repl_history

From 51d2efe567fdd877f8fc582acea68df8d386334a Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Thu, 7 Apr 2016 14:39:43 -0400
Subject: [PATCH 26/41] w

---
 .editorConfig | 0
 1 file changed, 0 insertions(+), 0 deletions(-)
 delete mode 100644 .editorConfig

diff --git a/.editorConfig b/.editorConfig
deleted file mode 100644
index e69de29..0000000

From f2247c296330c7b71deed750c7dd27232ae42eb9 Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Thu, 7 Apr 2016 14:40:25 -0400
Subject: [PATCH 27/41] editorconfig

---
 .editorconfig | 11 +++++++++++
 1 file changed, 11 insertions(+)
 create mode 100644 .editorconfig

diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..acb3b84
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,11 @@
+# EditorConfig is awesome: http://EditorConfig.org
+
+# top-most EditorConfig file
+root = true
+
+[*]
+charset = utf-8
+end_of_line = lf
+insert_final_newline = true
+indent_style = space
+indent_size = 2

From a14733856bf4d0b351ec2ba3bdd631e99db8d2fe Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Thu, 7 Apr 2016 17:30:51 -0400
Subject: [PATCH 28/41] added isRangeWithinBounds helper function

---
 m3u.js | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/m3u.js b/m3u.js
index 944f19b..11306f8 100644
--- a/m3u.js
+++ b/m3u.js
@@ -407,7 +407,18 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
   return this.sliceByIndex(start, end);
 };
 
-M3U.prototype.isRangeWithinIndexBounds = function isRangeWithinSecondsBounds (from, to) {
+M3U.prototype.isRangeWithinBounds = function isRangeWithinBounds (unit, from, to) {
+  switch (unit) {
+    case 'date':
+      return this.isRangeWithinDateBounds(from, to);
+    case 'seconds':
+      return this.isRangeWithinSecondsBounds(from, to);
+    case 'index':
+      return this.isRangeWithinIndexBounds(from, to);
+  }
+};
+
+M3U.prototype.isRangeWithinIndexBounds = function isRangeWithinIndexBounds (from, to) {
 
   var len = this.items.PlaylistItem.length;
 

From 8dedf80b20d153c4095dc744a45d89a905359883 Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Mon, 11 Apr 2016 17:31:50 -0400
Subject: [PATCH 29/41] make sure both sides are inclusive shile slicing

---
 m3u.js | 18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

diff --git a/m3u.js b/m3u.js
index 11306f8..75c8359 100644
--- a/m3u.js
+++ b/m3u.js
@@ -314,6 +314,10 @@ M3U.prototype.sliceBySeconds = function sliceBySeconds (from, to) {
     throw 'target `to` value, if truthy, must be greater than the `from` value';
   }
 
+  if (!this.items.PlaylistItem.length) {
+    return this.sliceByIndex();
+  }
+
   var duration = this.totalDuration();
   if (util.isNumber(from) && from > duration) {
     start = this.items.PlaylistItem.length;
@@ -329,7 +333,7 @@ M3U.prototype.sliceBySeconds = function sliceBySeconds (from, to) {
     total += item.properties.duration;
     currentIndex = i;
 
-    if (from != null && total >= from && start == null) {
+    if (from != null && total >= from && start == null) { // left-side-inclusive
       start = i;
       if (to == null) {
         return true;
@@ -337,7 +341,7 @@ M3U.prototype.sliceBySeconds = function sliceBySeconds (from, to) {
     }
 
     if (to != null && total >= to && end == null) {
-      end = i + 1;
+      end = total == to ? i + 1 : i; // right-side-inclusive
       return true;
     }
   });
@@ -353,6 +357,10 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
     throw new Error('at least 1 of the arguments needs to be a Date object');
   }
 
+  if (!this.items.PlaylistItem.length) {
+    return this.sliceByIndex();
+  }
+
   if (util.isNumber(from)) {
     from = new Date(to.getTime() - from * 1000);
   } else if (util.isNumber(to)) {
@@ -391,7 +399,7 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
   this.items.PlaylistItem.some(function(item, i) {
     current = item.properties.date;
 
-    if (from != null && current >= from && start == null) {
+    if (from != null && current >= from && start == null) { // right-side-inclusive
       start = i;
       if (to == null) {
         return true;
@@ -399,7 +407,7 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
     }
 
     if (to != null && current >= to && end == null) {
-      end = i;
+      end = current == to ? i + 1 : i; // // left-side-inclusive
       return true;
     }
   });
@@ -575,7 +583,7 @@ M3U.unserialize = function unserialize (object) {
 
   Object.keys(object.items).forEach(function(constructor) {
     m3u.items[constructor] = object.items[constructor].map(
-        Item.unserialize.bind(null, M3U[constructor])
+      Item.unserialize.bind(null, M3U[constructor])
     );
   });
   return m3u;

From 967d7659458075b9effca932eae51e7907f95fd8 Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Mon, 11 Apr 2016 18:10:17 -0400
Subject: [PATCH 30/41]  set the VOD/live mode correctly after dateMerge and
 uriMerge

---
 m3u.js | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/m3u.js b/m3u.js
index 75c8359..a792c39 100644
--- a/m3u.js
+++ b/m3u.js
@@ -164,8 +164,11 @@ M3U.prototype.mergeByUri = function mergeByUri (m3u) {
     }
   }
 
-  if (m3u.get('foundEndlist')) {
-    clone.set('foundEndlist', true);
+  if (m3u.isVOD()) {
+    clone.set('playlistType', 'VOD');
+  } else {
+    clone.set('playlistType', 'EVENT');
+    clone.set('foundEndlist', false);
   }
 
   return clone;
@@ -212,6 +215,7 @@ M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
     result.set('playlistType', 'VOD');
   } else {
     result.set('playlistType', 'EVENT');
+    result.set('foundEndlist', false);
   }
 
   return result;

From 8f0d784ac06c88a807c0dd0d424c3ee747239495 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Fri, 15 Apr 2016 02:05:48 -0400
Subject: [PATCH 31/41] node code util is crap, also comments fix

---
 m3u.js | 16 +++++-----------
 1 file changed, 5 insertions(+), 11 deletions(-)

diff --git a/m3u.js b/m3u.js
index a792c39..97b73fb 100644
--- a/m3u.js
+++ b/m3u.js
@@ -1,15 +1,8 @@
-var util;
-try {
-  util = require('util');
-} catch(e) {
-  util = {};
-}
-
-util.isNumber = util.isNumber || function (n) {
+var util = {};
+util.isNumber = function (n) {
   return !isNaN(parseFloat(n)) && isFinite(n);
 };
-
-util.isDate = util.isDate || function (d) {
+util.isDate = function (d) {
   return d instanceof Date && !isNaN(d.valueOf());
 };
 
@@ -135,7 +128,7 @@ M3U.prototype.concat = function concat (m3u) {
 };
 
 // backward-compatible merge function, that just concats and mutates self
-// todo: remove this, since it's really a merge, it's just a concat()
+// todo: remove this, since it's really not a merge, it's just a concat()
 M3U.prototype.merge = function merge (m3u) {
   var clone = this.concat(m3u);
   this.items.PlaylistItem = clone.items.PlaylistItem;
@@ -143,6 +136,7 @@ M3U.prototype.merge = function merge (m3u) {
   return this;
 };
 
+// todo: too O(n^2) too slow - maybe use a hash of URIs
 M3U.prototype.mergeByUri = function mergeByUri (m3u) {
   var clone = this.concat(m3u);
 

From 53e0be51768437fe4d53188f7dfbee82718e6839 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Fri, 15 Apr 2016 03:14:39 -0400
Subject: [PATCH 32/41] when concat preserve VOD/Live state

---
 m3u.js | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/m3u.js b/m3u.js
index 97b73fb..38a5205 100644
--- a/m3u.js
+++ b/m3u.js
@@ -124,6 +124,13 @@ M3U.prototype.concat = function concat (m3u) {
 
   clone.items.PlaylistItem = clone.items.PlaylistItem.concat(m3u.items.PlaylistItem);
 
+  if (m3u.isVOD()) {
+    clone.set('playlistType', 'VOD');
+  } else {
+    clone.set('playlistType', 'EVENT');
+    clone.set('foundEndlist', false);
+  }
+
   return clone;
 };
 

From 7151198909bb8580f7c25d088cf03648377e9ca4 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Thu, 12 May 2016 15:50:00 -0400
Subject: [PATCH 33/41] wtf ?

```
{
	"message": "createM3U is not defined",
	"stack": "ReferenceError: createM3U is not defined\n    at M3U.mergeByDate (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/m3u8/m3u.js:190:80)\n    at /Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/lib/index.js:295:24\n    at tryCatchResolve (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/apply.js:46:23)\n    at callAndResolve (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/apply.js:30:12)\n    at callAndResolveNext (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/apply.js:40:4)\n    at tryCatchReject3 (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/makePromise.js:856:7)\n    at runContinuation3 (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/makePromise.js:814:4)\n    at Fulfilled.fold (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/makePromise.js:588:4)\n    at callAndResolve (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/apply.js:34:12)\n    at callAndResolveNext (/Users/akhoury/Perforce/akhoury_azizs-mac-mini_4287/speech/ramp/sites/m3u8-service/node_modules/when/lib/apply.js:40:4)"
}
```
---
 m3u.js | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/m3u.js b/m3u.js
index 38a5205..d674a74 100644
--- a/m3u.js
+++ b/m3u.js
@@ -187,8 +187,8 @@ M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
     dateA0 = clone.items.PlaylistItem[0].get('date');
     dateAN = clone.items.PlaylistItem[clone.items.PlaylistItem.length - 1].get('date');
   }
-  m3uPre = dateA0 ? m3u.sliceByDate(null, new Date((+new Date(dateA0)) - 1)) : createM3U(); // -1 ms to make it exclusive
-  m3uPost = dateAN ? m3u.sliceByDate(new Date((+new Date(dateAN)) + 1)) : createM3U(); // +1 ms to make it exclusive
+  m3uPre = dateA0 ? m3u.sliceByDate(null, new Date((+new Date(dateA0)) - 1)) : M3U.create(); // -1 ms to make it exclusive
+  m3uPost = dateAN ? m3u.sliceByDate(new Date((+new Date(dateAN)) + 1)) : M3U.create(); // +1 ms to make it exclusive
 
   var gaps = clone.findDateGaps(options);
   gaps.forEach(function(gap) {

From 6803773a2e09a6b215ac840c37f2233630d42bd2 Mon Sep 17 00:00:00 2001
From: akhoury <bentael@gmail.com>
Date: Sun, 22 May 2016 11:18:51 -0400
Subject: [PATCH 34/41] add isMaster()

---
 m3u.js | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/m3u.js b/m3u.js
index d674a74..3987805 100644
--- a/m3u.js
+++ b/m3u.js
@@ -561,6 +561,10 @@ M3U.prototype.isLive = function isLive () {
   return !this.isVOD();
 };
 
+M3U.prototype.isMaster = function isMaster () {
+  return !! (this.items.StreamItem.length || this.items.MediaItem.length || this.items.IframeStreamItem.length);
+};
+
 M3U.prototype.clone = function clone () {
   return M3U.unserialize(this.serialize());
 };

From 0390f413606e88a7d9d375a157d0c6a0fd23e32e Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Tue, 24 May 2016 15:45:22 -0400
Subject: [PATCH 35/41] fix isRangeWithinDateBounds upper bound bug

---
 m3u.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/m3u.js b/m3u.js
index 3987805..d94c5f9 100644
--- a/m3u.js
+++ b/m3u.js
@@ -501,7 +501,7 @@ M3U.prototype.isRangeWithinDateBounds = function isRangeWithinDateBounds (from,
   }
 
   if (to != null) {
-    right = to <= this.items.PlaylistItem[len - 1].properties.date;
+    right = this.items.PlaylistItem[len - 1].properties.date <= to;
   }
 
   return left && right;

From c0a390d7f044b0255534b708bb86bdcea788faa5 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Tue, 31 May 2016 13:51:22 -0400
Subject: [PATCH 36/41] correct EXT-X-MEDIA-SEQUENCE calculation on slicing

---
 m3u.js           | 8 ++++++++
 test/m3u.test.js | 4 +++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/m3u.js b/m3u.js
index d94c5f9..bf1ff57 100644
--- a/m3u.js
+++ b/m3u.js
@@ -147,6 +147,7 @@ M3U.prototype.merge = function merge (m3u) {
 M3U.prototype.mergeByUri = function mergeByUri (m3u) {
   var clone = this.concat(m3u);
 
+  // todo: also, i don't think this is correct
   if (m3u.get('mediaSequence') < clone.get('mediaSequence')) {
     clone.set('mediaSequence', m3u.get('mediaSequence'));
   }
@@ -304,6 +305,13 @@ M3U.prototype.sliceByIndex = M3U.prototype.slice = function sliceByIndex (start,
     m3u.set('playlistType', 'VOD');
   }
 
+  var mediaSequence = m3u.get('mediaSequence');
+  // assume 1 if it doesn't exists https://tools.ietf.org/html/draft-pantos-http-live-streaming-01#section-3.1.2
+  if (!mediaSequence || mediaSequence < 0) {
+    mediaSequence = 1;
+  }
+  m3u.set('mediaSequence', mediaSequence + start);
+
   m3u.items.PlaylistItem = m3u.items.PlaylistItem.slice(start, end);
 
   return m3u;
diff --git a/test/m3u.test.js b/test/m3u.test.js
index 2b3053c..8820749 100644
--- a/test/m3u.test.js
+++ b/test/m3u.test.js
@@ -254,10 +254,12 @@ describe('m3u', function() {
       m3u1.addPlaylistItem({});
       m3u1.addPlaylistItem({});
       m3u1.addPlaylistItem({});
+      m3u1.set('mediaSequence', 5);
 
       var m3u2 = m3u1.sliceByIndex(1, 3);
-      m3u2.items.PlaylistItem.length.should.eql(2);
 
+      m3u2.get('mediaSequence').should.eql(6);
+      m3u2.items.PlaylistItem.length.should.eql(2);
     });
   });
 

From 21e49b1b73556207cf40d8eb046dc963c75feddd Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Wed, 8 Jun 2016 17:12:05 -0400
Subject: [PATCH 37/41] date slicing/merging is more accurate now

---
 m3u.js           | 41 +++++++++++++++++++++++++++------------
 test/m3u.test.js | 50 +++++++++++++++++++++++++++++++++++-------------
 2 files changed, 66 insertions(+), 25 deletions(-)

diff --git a/m3u.js b/m3u.js
index bf1ff57..74f86e1 100644
--- a/m3u.js
+++ b/m3u.js
@@ -177,19 +177,23 @@ M3U.prototype.mergeByUri = function mergeByUri (m3u) {
 };
 
 M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
+
   var clone = this.clone(m3u);
 
   options = options || {};
 
   var len = clone.items.PlaylistItem.length;
-  var dateA0, dateAN, m3uPre, m3uPost;
+  var item0, itemN, dateA0, dateAN, m3uPre, m3uPost;
 
   if (len) {
-    dateA0 = clone.items.PlaylistItem[0].get('date');
-    dateAN = clone.items.PlaylistItem[clone.items.PlaylistItem.length - 1].get('date');
+    item0 = clone.items.PlaylistItem[0];
+    dateA0 = item0.get('date');
+    itemN = clone.items.PlaylistItem[clone.items.PlaylistItem.length - 1];
+    dateAN = itemN.get('date');
   }
-  m3uPre = dateA0 ? m3u.sliceByDate(null, new Date((+new Date(dateA0)) - 1)) : M3U.create(); // -1 ms to make it exclusive
-  m3uPost = dateAN ? m3u.sliceByDate(new Date((+new Date(dateAN)) + 1)) : M3U.create(); // +1 ms to make it exclusive
+
+  m3uPre = dateA0 ? m3u.sliceByDate(null, new Date((+new Date(dateA0)))) : M3U.create();
+  m3uPost = dateAN ? m3u.sliceByDate(new Date((+new Date(dateAN)) + itemN.get('duration') * 1000)) : M3U.create();
 
   var gaps = clone.findDateGaps(options);
   gaps.forEach(function(gap) {
@@ -354,7 +358,9 @@ M3U.prototype.sliceBySeconds = function sliceBySeconds (from, to) {
     }
 
     if (to != null && total >= to && end == null) {
-      end = total == to ? i + 1 : i; // right-side-inclusive
+      // we're adding the +1 here to include the current segment,
+      // it is still considered exclusive, since the current value here is the total duration, so the end of each segment
+      end = i + 1;
       return true;
     }
   });
@@ -407,20 +413,31 @@ M3U.prototype.sliceByDate = function sliceByDate (from, to) {
     end = 0;
   }
 
-  var current;
+  from = from && from.valueOf ? from.valueOf() : from;
+  to = to && to.valueOf ? to.valueOf(): to;
+
+  var currentStart;
+  var currentEnd;
 
   this.items.PlaylistItem.some(function(item, i) {
-    current = item.properties.date;
+    currentStart = new Date(item.properties.date);
+    currentEnd = new Date(item.properties.date);
+    currentEnd.setSeconds(currentStart.getSeconds() + item.properties.duration);
 
-    if (from != null && current >= from && start == null) { // right-side-inclusive
-      start = i;
+    currentStart = currentEnd.valueOf();
+    currentEnd = currentEnd.valueOf();
+
+    if (from != null && currentEnd >= from && start == null) { // right-side-inclusive
+      start = currentEnd == from ? i + 1 : i; // still exclude directly behind segment
       if (to == null) {
         return true;
       }
     }
 
-    if (to != null && current >= to && end == null) {
-      end = current == to ? i + 1 : i; // // left-side-inclusive
+    if (to != null && currentEnd >= to && end == null) {
+      // we're adding the +1 here to include the current segment,
+      // it is still considered exclusive, since the current = date + duration, so the end of each segment
+      end = currentStart >= to ? i + 1 : i;
       return true;
     }
   });
diff --git a/test/m3u.test.js b/test/m3u.test.js
index 8820749..55f6f5f 100644
--- a/test/m3u.test.js
+++ b/test/m3u.test.js
@@ -216,16 +216,16 @@ describe('m3u', function() {
       var m3u1 = getM3u();
       var ms0 = +new Date() - (24 * 60 * 60 * 1000);
 
-      m3u1.addPlaylistItem({uri: 'a.3', date: new Date(ms0)});
-      m3u1.addPlaylistItem({uri: 'a.4', date: new Date(ms0 + 10000)});
-      m3u1.addPlaylistItem({uri: 'a.6', date: new Date(ms0 + 30000)});
+      m3u1.addPlaylistItem({uri: 'a.3', date: new Date(ms0), duration: 10});
+      m3u1.addPlaylistItem({uri: 'a.4', date: new Date(ms0 + 10000), duration: 10});
+      m3u1.addPlaylistItem({uri: 'a.6', date: new Date(ms0 + 30000), duration: 10});
 
       var m3u2 = getM3u();
-      m3u2.addPlaylistItem({uri: 'b.1', date: new Date(ms0 - 20000)});
-      m3u2.addPlaylistItem({uri: 'b.2', date: new Date(ms0 - 10000)});
-      m3u2.addPlaylistItem({uri: 'b.5', date: new Date(ms0 + 20000)});
-      m3u2.addPlaylistItem({uri: 'b.6', date: new Date(ms0 + 30000)});
-      m3u2.addPlaylistItem({uri: 'b.7', date: new Date(ms0 + 40000)});
+      m3u2.addPlaylistItem({uri: 'b.1', date: new Date(ms0 - 20000), duration: 10});
+      m3u2.addPlaylistItem({uri: 'b.2', date: new Date(ms0 - 10000), duration: 10});
+      m3u2.addPlaylistItem({uri: 'b.5', date: new Date(ms0 + 20000), duration: 10});
+      m3u2.addPlaylistItem({uri: 'b.6', date: new Date(ms0 + 30000), duration: 10});
+      m3u2.addPlaylistItem({uri: 'b.7', date: new Date(ms0 + 40000), duration: 10});
 
       m3u1 = m3u1.mergeByDate(m3u2);
 
@@ -283,15 +283,39 @@ describe('m3u', function() {
       var m3u1 = getM3u();
 
       var ms0 = +new Date();
+      var duration = 10;
 
-      m3u1.addPlaylistItem({date: new Date(ms0)});
-      m3u1.addPlaylistItem({date: new Date(ms0 + 5000)});
-      m3u1.addPlaylistItem({date: new Date(ms0 + 10000)});
-      m3u1.addPlaylistItem({date: new Date(ms0 + 15000)});
+      var len = 4;
+      for (var i = 0; i < len; i++) {
+        m3u1.addPlaylistItem({date: new Date(ms0 + (duration * i * 1000)), duration: duration});
+      }
 
-      var m3u2 = m3u1.sliceByDate(new Date(ms0 + 5000), new Date(ms0 + 10001));
+      var m3uA = m3u1.sliceByDate(new Date(ms0 + 7000), new Date(ms0 + 17000));
+      m3uA.items.PlaylistItem.length.should.eql(2);
+
+      var m3uB = m3u1.sliceByDate(new Date(ms0 + 10000), new Date(ms0 + 20000));
+      m3uB.items.PlaylistItem.length.should.eql(1);
+
+      var m3uC = m3u1.sliceByDate(new Date(ms0 + 10000), new Date(ms0 + 31000));
+      m3uC.items.PlaylistItem.length.should.eql(3);
+
+      var m3uD = m3u1.sliceByDate(new Date(ms0 + 11000), new Date(ms0 + 21000));
+      m3uD.items.PlaylistItem.length.should.eql(2);
+
+      var m3uE = m3u1.sliceByDate(new Date(ms0 + 11000), new Date(ms0 + 20000));
+      m3uE.items.PlaylistItem.length.should.eql(1);
+
+      var m3u2 = m3u1.sliceByDate(new Date(ms0 + 10000), new Date(ms0 + 21000));
+      m3u2.items.PlaylistItem[0].properties.date.valueOf().should.eql((new Date(ms0 + (duration /* *1 */ * 1000))).valueOf());
+      m3u2.items.PlaylistItem[m3u2.items.PlaylistItem.length - 1].properties.date.valueOf().should.eql((new Date(ms0 + (duration * 2 * 1000))).valueOf());
       m3u2.items.PlaylistItem.length.should.eql(2);
 
+      var m3u3 = m3u1.sliceByDate(new Date(ms0 + 10001), new Date(ms0 + 20000));
+      m3u3.items.PlaylistItem.length.should.eql(1);
+
+      var m3u4 = m3u1.sliceByDate(new Date(ms0 + 10000), new Date(ms0 + 20001));
+      m3u4.items.PlaylistItem.length.should.eql(2);
+
     });
   });
 

From 450eb3759c6abad117229fd0c62ff73d0fb94d10 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Wed, 22 Jun 2016 11:56:59 -0400
Subject: [PATCH 38/41] reset target duration when
 slicing/concat/merging/adding/removing items

---
 m3u.js | 50 +++++++++++++++++++++++++++++++++++++++++++-------
 1 file changed, 43 insertions(+), 7 deletions(-)

diff --git a/m3u.js b/m3u.js
index 74f86e1..dd6cb9d 100644
--- a/m3u.js
+++ b/m3u.js
@@ -45,11 +45,14 @@ M3U.prototype.addItem = function addItem(item) {
 };
 
 M3U.prototype.addPlaylistItem = function addPlaylistItem(data) {
-  this.items.PlaylistItem.push(M3U.PlaylistItem.create(data));
+  var newItem = M3U.PlaylistItem.create(data);
+  this.maybeSetTargetDuration(newItem.get('duration'));
+  this.items.PlaylistItem.push(newItem);
 };
 
 M3U.prototype.insertPlaylistItemsAfter = function insertPlaylistItemsAfter (newItems, afterItem) {
   var index = this.items.PlaylistItem.length;
+  var self = this;
 
   if (!(afterItem instanceof M3U.PlaylistItem)) {
     afterItem = M3U.PlaylistItem.create(afterItem);
@@ -57,8 +60,9 @@ M3U.prototype.insertPlaylistItemsAfter = function insertPlaylistItemsAfter (newI
 
   newItems = [].concat(newItems).map(function(newItem) {
     if (!(newItem instanceof M3U.PlaylistItem)) {
-      return M3U.PlaylistItem.create(newItem);
+      newItem = M3U.PlaylistItem.create(newItem);
     }
+    self.maybeSetTargetDuration(newItem.get('duration'));
     return newItem;
   });
 
@@ -70,6 +74,7 @@ M3U.prototype.insertPlaylistItemsAfter = function insertPlaylistItemsAfter (newI
   });
 
   this.items.PlaylistItem = this.items.PlaylistItem.slice(0, index + 1).concat(newItems).concat(this.items.PlaylistItem.slice(index + 1));
+  this.resetTargetDuration(true);
   return this;
 };
 
@@ -79,6 +84,7 @@ M3U.prototype.removePlaylistItem = function removePlaylistItem(index) {
   } else {
     throw new RangeError('M3U PlaylistItem out of range');
   }
+  this.resetTargetDuration(true);
 };
 
 M3U.prototype.addMediaItem = function addMediaItem(data) {
@@ -111,12 +117,37 @@ M3U.prototype.totalDuration = function totalDuration() {
   }, 0);
 };
 
-M3U.prototype.concat = function concat (m3u) {
-  var clone = this.clone();
+// if one is passed in, try it, if none is passed, iterate and find it.
+M3U.prototype.resetTargetDuration = function resetTargetDuration (newTargetDuration) {
+  var self = this;
+
+  // if you just want to set it to a number, don't use this function, nor maybeSetTargetDuration, just use this.set('targetDuration', Math.round(newTargetDuration))
+
+  if (util.isNumber(newTargetDuration)) {
+    this.maybeSetTargetDuration(newTargetDuration);
+  } else {
+    // force reset, so we set it to 0, this way, the 1st item will set it.
+    if (newTargetDuration === true) {
+      this.set('targetDuration', 0);
+    }
+    this.items.PlaylistItem.forEach(function(item) {
+      self.maybeSetTargetDuration(item.get('duration'));
+    });
+  }
+  return this.get('targetDuration');
+};
 
-  if (m3u.get('targetDuration') > clone.get('targetDuration')) {
-    clone.set('targetDuration', m3u.get('targetDuration'));
+M3U.prototype.maybeSetTargetDuration  = function maybeSetTargetDuration (newTargetDuration) {
+  // round to nearest integer https://tools.ietf.org/html/draft-pantos-http-live-streaming-19#section-4.3.3.1
+  newTargetDuration = Math.round(newTargetDuration);
+
+  if (newTargetDuration > this.get('targetDuration')) {
+    this.set('targetDuration', newTargetDuration);
   }
+};
+
+M3U.prototype.concat = function concat (m3u) {
+  var clone = this.clone();
 
   if (m3u.items.PlaylistItem[0]) {
     m3u.items.PlaylistItem[0].set('discontinuity', true);
@@ -131,6 +162,8 @@ M3U.prototype.concat = function concat (m3u) {
     clone.set('foundEndlist', false);
   }
 
+  clone.resetTargetDuration(m3u.get('targetDuration'));
+
   return clone;
 };
 
@@ -139,7 +172,7 @@ M3U.prototype.concat = function concat (m3u) {
 M3U.prototype.merge = function merge (m3u) {
   var clone = this.concat(m3u);
   this.items.PlaylistItem = clone.items.PlaylistItem;
-  this.set('targetDuration', clone.get('targetDuration'));
+  this.resetTargetDuration(clone.get('targetDuration'));
   return this;
 };
 
@@ -162,6 +195,8 @@ M3U.prototype.mergeByUri = function mergeByUri (m3u) {
           segments[i].set('discontinuity', true);
         }
         segments.splice(j--, 1);
+      } else {
+        clone.maybeSetTargetDuration(segments[i].get('duration'));
       }
     }
   }
@@ -317,6 +352,7 @@ M3U.prototype.sliceByIndex = M3U.prototype.slice = function sliceByIndex (start,
   m3u.set('mediaSequence', mediaSequence + start);
 
   m3u.items.PlaylistItem = m3u.items.PlaylistItem.slice(start, end);
+  m3u.resetTargetDuration(true);
 
   return m3u;
 };

From 0a3403577b65076f5581fbb42970b6f0cb3826b1 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Mon, 27 Jun 2016 23:38:16 -0400
Subject: [PATCH 39/41] delete playlistType when sliding window

---
 m3u.js | 22 +++++++++++++++++++---
 1 file changed, 19 insertions(+), 3 deletions(-)

diff --git a/m3u.js b/m3u.js
index dd6cb9d..a447480 100644
--- a/m3u.js
+++ b/m3u.js
@@ -339,9 +339,25 @@ M3U.prototype.sliceByIndex = M3U.prototype.slice = function sliceByIndex (start,
     end = len;
   }
 
-  // if live and both start & end were within the length of the stream, make it look like a VOD
-  if (! m3u.isVOD() && start < len && end < len) {
-    m3u.set('playlistType', 'VOD');
+  if (m3u.isLive()) {
+    if (start < len && end < len) {
+      // if live and both start & end were within the length of the stream, make it look like a VOD
+      m3u.set('playlistType', 'VOD');
+
+    } else if (start > 0 && end == len) {
+      /*
+          One thing I noticed recently is that if we are implementing a LIVE sliding window, we can't have a `playlistType`, (otherwise Safari refuses to play more than 1 segment)
+
+          https://tools.ietf.org/html/draft-pantos-http-live-streaming-07#page-19
+          > the Playlist file MAY contain an EXT-X-PLAYLIST-TYPE tag
+          > with a value of either EVENT or VOD.  If the tag is present and has a
+          > value of EVENT, the server MUST NOT change or delete any part of the
+          > Playlist file (although it MAY append lines to it)
+
+          So, If we slice an m3u and `isLive()` is true, and the `start` value of slicing is greater than 0, then we need to remove the playlistType
+       */
+      delete m3u.properties['playlistType'];
+    }
   }
 
   var mediaSequence = m3u.get('mediaSequence');

From 059c78d903d502bdcc8b2c236f2acef2c9b70936 Mon Sep 17 00:00:00 2001
From: Aziz Khoury <bentael@gmail.com>
Date: Tue, 28 Jun 2016 00:05:56 -0400
Subject: [PATCH 40/41] delete playlistType all the time when live, it's
 uncessary

---
 m3u.js | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/m3u.js b/m3u.js
index a447480..178d3ad 100644
--- a/m3u.js
+++ b/m3u.js
@@ -158,7 +158,7 @@ M3U.prototype.concat = function concat (m3u) {
   if (m3u.isVOD()) {
     clone.set('playlistType', 'VOD');
   } else {
-    clone.set('playlistType', 'EVENT');
+    delete clone.properties['playlistType'];
     clone.set('foundEndlist', false);
   }
 
@@ -204,7 +204,7 @@ M3U.prototype.mergeByUri = function mergeByUri (m3u) {
   if (m3u.isVOD()) {
     clone.set('playlistType', 'VOD');
   } else {
-    clone.set('playlistType', 'EVENT');
+    delete clone.properties['playlistType'];
     clone.set('foundEndlist', false);
   }
 
@@ -255,7 +255,7 @@ M3U.prototype.mergeByDate = function mergeByDate (m3u, options) {
   if (m3uTail.isVOD()) {
     result.set('playlistType', 'VOD');
   } else {
-    result.set('playlistType', 'EVENT');
+    delete result.properties['playlistType'];
     result.set('foundEndlist', false);
   }
 

From 9ebaaec52aa5a67ded054b13cde51cb5a8d78d45 Mon Sep 17 00:00:00 2001
From: Viktor Zdanovich <viktor.zdanovich@cxense.com>
Date: Wed, 10 Jan 2018 19:36:01 +0400
Subject: [PATCH 41/41] added EXT-X-DISCONTINUITY-SEQUENCE to be set through
 discontinuitySequence prop

---
 m3u.js | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/m3u.js b/m3u.js
index 178d3ad..28869b6 100644
--- a/m3u.js
+++ b/m3u.js
@@ -717,19 +717,21 @@ var toStringIgnoredProperties = {
 };
 
 var dataTypes = {
-  iframesOnly    : 'boolean',
-  targetDuration : 'integer',
-  mediaSequence  : 'integer',
-  version        : 'integer'
+  iframesOnly            : 'boolean',
+  targetDuration         : 'integer',
+  mediaSequence          : 'integer',
+  discontinuitySequence  : 'integer',
+  version                : 'integer'
 };
 
 var propertyMap = [
-  { tag: 'EXT-X-ALLOW-CACHE',    key: 'allowCache' },
-  { tag: 'EXT-X-I-FRAMES-ONLY',  key: 'iframesOnly' },
-  { tag: 'EXT-X-MEDIA-SEQUENCE', key: 'mediaSequence' },
-  { tag: 'EXT-X-PLAYLIST-TYPE',  key: 'playlistType' },
-  { tag: 'EXT-X-TARGETDURATION', key: 'targetDuration' },
-  { tag: 'EXT-X-VERSION',        key: 'version' }
+  { tag: 'EXT-X-ALLOW-CACHE',            key: 'allowCache' },
+  { tag: 'EXT-X-I-FRAMES-ONLY',          key: 'iframesOnly' },
+  { tag: 'EXT-X-MEDIA-SEQUENCE',         key: 'mediaSequence' },
+  { tag: 'EXT-X-DISCONTINUITY-SEQUENCE', key: 'discontinuitySequence' },
+  { tag: 'EXT-X-PLAYLIST-TYPE',          key: 'playlistType' },
+  { tag: 'EXT-X-TARGETDURATION',         key: 'targetDuration' },
+  { tag: 'EXT-X-VERSION',                key: 'version' }
 ];
 
 propertyMap.findByTag = function findByTag (tag) {