From 151bae3566d8b4a1c36ed3a368c515bd1349d2b6 Mon Sep 17 00:00:00 2001
From: Anthony Weems <amlweems@gmail.com>
Date: Tue, 25 Feb 2014 14:44:34 -0600
Subject: [PATCH] Add support for ocw.mit.edu video lectures

---
 youtube_dl/extractor/__init__.py |  2 +-
 youtube_dl/extractor/mit.py      | 54 ++++++++++++++++++++++++++++++++
 2 files changed, 55 insertions(+), 1 deletion(-)

diff --git a/youtube_dl/extractor/__init__.py b/youtube_dl/extractor/__init__.py
index 8eff3df418..ee081b1f35 100644
--- a/youtube_dl/extractor/__init__.py
+++ b/youtube_dl/extractor/__init__.py
@@ -137,7 +137,7 @@ from .malemotion import MalemotionIE
 from .mdr import MDRIE
 from .metacafe import MetacafeIE
 from .metacritic import MetacriticIE
-from .mit import TechTVMITIE, MITIE
+from .mit import TechTVMITIE, MITIE, OCWMITIE
 from .mixcloud import MixcloudIE
 from .mpora import MporaIE
 from .mofosex import MofosexIE
diff --git a/youtube_dl/extractor/mit.py b/youtube_dl/extractor/mit.py
index 76b717fe5d..7c40cb8bd3 100644
--- a/youtube_dl/extractor/mit.py
+++ b/youtube_dl/extractor/mit.py
@@ -3,6 +3,7 @@ import json
 
 from .common import InfoExtractor
 from ..utils import (
+    compat_urlparse,
     clean_html,
     get_element_by_id,
 )
@@ -81,3 +82,56 @@ class MITIE(TechTVMITIE):
         embed_url = self._search_regex(r'<iframe .*?src="(.+?)"', webpage,
             u'embed url')
         return self.url_result(embed_url, ie='TechTVMIT')
+
+class OCWMITIE(InfoExtractor):
+    IE_NAME = u'ocw.mit.edu'
+    _VALID_URL = r'^http://ocw\.mit\.edu/courses/(?P<topic>[a-z0-9\-]+)'
+    _BASE_URL = u'http://ocw.mit.edu/'
+
+    _TESTS = [
+        {
+            u'url': u'http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-041-probabilistic-systems-analysis-and-applied-probability-fall-2010/video-lectures/lecture-7-multiple-variables-expectations-independence/',
+            u'md5': u'348bef727b573c0bd9ad8a7c08c89ebd',
+            u'info_dict': {
+                u'title': u'7. Discrete Random Variables III',
+                u'description': u'In this lecture, the professor discussed multiple random variables, expectations, and binomial distribution.',
+                u'subtitles': u'http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-041-probabilistic-systems-analysis-and-applied-probability-fall-2010/video-lectures/lecture-7-multiple-variables-expectations-independence/MIT6_041F11_lec07_300k.mp4.srt'
+            }
+        },
+        {
+            u'url': u'http://ocw.mit.edu/courses/mathematics/18-01sc-single-variable-calculus-fall-2010/1.-differentiation/part-a-definition-and-basic-rules/session-1-introduction-to-derivatives/',
+            u'md5': u'f4a434f08f15e581eb67cec0b57bcf6f',
+            u'info_dict': {
+                u'title': u'Lec 1 _ MIT 18.01 Single Variable Calculus, Fall 2007',
+                u'subtitles': u'http://ocw.mit.edu//courses/mathematics/18-01sc-single-variable-calculus-fall-2010/ocw-18.01-f07-lec01_300k.SRT'
+            }
+        }
+    ]
+
+    def _real_extract(self, url):
+        webpage = self._download_webpage(url, self.IE_NAME)
+        title = self._html_search_meta(u'WT.cg_s', webpage)
+        description = self._html_search_meta(u'Description', webpage)
+
+        # search for call to ocw_embed_chapter_media(container_id, media_url, provider, page_url, image_url, start, stop, captions_file)
+        embed_chapter_media = re.search(r'ocw_embed_chapter_media\((.+?)\)', webpage)
+        if embed_chapter_media:
+            metadata = re.sub(r'[\'"]', u'', embed_chapter_media.group(1))
+            metadata = re.split(r', ?', metadata)
+            yt = metadata[1]
+            subs = compat_urlparse.urljoin(self._BASE_URL, metadata[7])
+        else:
+            # search for call to ocw_embed_chapter_media(container_id, media_url, provider, page_url, image_url, captions_file)
+            embed_media = re.search(r'ocw_embed_media\((.+?)\)', webpage)
+            if embed_media:
+                metadata = re.sub(r'[\'"]', u'', embed_media.group(1))
+                metadata = re.split(r', ?', metadata)
+                yt = metadata[1]
+                subs = compat_urlparse.urljoin(self._BASE_URL, metadata[5])
+            else:
+                raise ExtractorError('Unable to find embedded YouTube video.')
+
+        data = self.url_result(yt, 'Youtube')
+        data['subtitles'] = subs
+        
+        return data