import groovy.json.JsonSlurper

import org.serviio.library.metadata.*
import org.serviio.library.online.*
 


/**
 * YouTube.com content URL extractor plugin. 
 * 
 * It uses YouTube API v3 for retrieving playlists. 
 * 
 * @see http://en.wikipedia.org/wiki/Youtube#Quality_and_codecs
 *  
 * @author Petr Nejedly
 *
 */
class YouTube extends WebResourceUrlExtractor {

    final VALID_RESOURCE_URL = '^https?://www.googleapis.com/youtube/.*$'
    /* Listed in order of quality */
    final availableFormats = ['37', '46', '22', '45', '35', '34', '18', '44', '43', '6', '5']
    
    String getExtractorName() {
        return getClass().getName()
    }
    
    boolean extractorMatches(URL feedUrl) {
        return feedUrl ==~ VALID_RESOURCE_URL
    }
    
    public int getVersion() {
        return 3;
    }
    
    @Override
    WebResourceContainer extractItems(URL resourceUrl, int maxItemsToRetrieve) {
      final user_agent = "Mozilla/5.0 (compatible; MSIE 10.0; Windows NT 6.1; Trident/6.0)"
      final api_key = "AIzaSyAPeRAlHMSa_WQMbarc_ffse7-t0-DOuVQ" // this is Serviio API key, don't use it for anything else please, they are easy to get


      if (maxItemsToRetrieve == -1) maxItemsToRetrieve = 50
      
      if (resourceUrl.toString().contains("channels")){
        def channelUrl = new URL(resourceUrl.toString() + "&part=contentDetails" + "&maxResults=" + maxItemsToRetrieve + "&key=" + api_key)  
        def channeljson = new JsonSlurper().parseText(openURL(channelUrl, user_agent))
        def uploadPlaylist = channeljson.items[0].contentDetails.relatedPlaylists.uploads
             
        resourceUrl = new URL("https://www.googleapis.com/youtube/v3/playlistItems?playlistId=$uploadPlaylist")
      }      
      
      def items = []    
      def nextPageToken = ""
        
     while(true){
    
      def apiUrl = new URL(resourceUrl.toString() + "&part=snippet" + "&maxResults=" + maxItemsToRetrieve + "&key=" + api_key + "&pageToken=" + nextPageToken)
     

          def json = new JsonSlurper().parseText(openURL(apiUrl, user_agent))
          
          json.items.each() {
             if (it.snippet.title != "Deleted video" && it.snippet.title != "Private video") {
                items.add(new WebResourceItem(title : it.snippet.title,
                                              additionalInfo : ['videoId' : it.snippet.resourceId.videoId, 'thumb' : it.snippet.thumbnails.high.url]))
             }
          }
          nextPageToken=json.nextPageToken
          if(nextPageToken==""||nextPageToken==null)break
                       
      } 

       
 
      def containerThumbnailUrl = items?.find { it -> it.additionalInfo['thumb'] != null }?.additionalInfo['thumb']

      return new WebResourceContainer(items: items, thumbnailUrl: containerThumbnailUrl)
    }

    @Override
    protected ContentURLContainer extractUrl(WebResourceItem wrItem, PreferredQuality requestedQuality) {
        
        def contentUrl
        def expiryDate
        def expiresImmediately
        def cacheKey
        
        def videoId = wrItem.additionalInfo['videoId']
        def thumbnailUrl = wrItem.additionalInfo['thumb']
        
        for (elType in ['&el=embedded', '&el=detailpage', '&el=vevo', '']) {           
            def videoInfoUrl = "http://www.youtube.com/get_video_info?&video_id=$videoId$elType&ps=default&eurl=&gl=US&hl=en"
            //log("Loading video info: $videoInfoUrl")
            def videoInfoWebPage = new URL(videoInfoUrl).getText()
            def parameters = [:]
        
            videoInfoWebPage.split('&').each{item -> addParameter(item, parameters, '=')}
            if(parameters.containsKey('token')) {        
                def formatUrlMapString = parameters['fmt_url_map']    
                def urlEncodedUrlMapString = parameters['url_encoded_fmt_stream_map']
                def adaptiveFormatsMapString = parameters['adaptive_fmts']
                def allFormatUrlMap = [:]
                
                def test = URLDecoder.decode(adaptiveFormatsMapString,'UTF-8').split(',').each{item -> addParameter(item, allFormatUrlMap, '\\|')}
                
                if (formatUrlMapString != null && formatUrlMapString.length() > 0 ) {
                    URLDecoder.decode(formatUrlMapString,'UTF-8').split(',').each{item -> addParameter(item, allFormatUrlMap, '\\|')}                        
                } else {                 
                    if (urlEncodedUrlMapString != null && urlEncodedUrlMapString.length() > 0 ) {                     
                        processStreamData(urlEncodedUrlMapString, allFormatUrlMap)
                    }    
                    if (adaptiveFormatsMapString != null && adaptiveFormatsMapString.length() > 0 ) {
                        processStreamData(adaptiveFormatsMapString, allFormatUrlMap)
                    }
                }
               // get available formats for requested quality, sorted by quality from highest
               def formatUrlMap = new LinkedHashMap()
               if(requestedQuality == PreferredQuality.HIGH) {
                   // best quality, get the first from the list
                   sortAvailableFormatUrls(availableFormats, allFormatUrlMap, formatUrlMap)
                   def selectedUrl = formatUrlMap.entrySet().toList().head()
                   contentUrl = selectedUrl.getValue()
                   cacheKey = getCacheKey(videoId, selectedUrl.getKey())
               } else if (requestedQuality == PreferredQuality.MEDIUM) {
                   // work with subset of available formats, starting at the position of format 35 and then take the best quality from there
                   sortAvailableFormatUrls(availableFormats.getAt(4..availableFormats.size-1), allFormatUrlMap, formatUrlMap)
                   def selectedUrl = formatUrlMap.entrySet().toList().head()
                   contentUrl = selectedUrl.getValue()
                   cacheKey = getCacheKey(videoId, selectedUrl.getKey())
               } else {
                   // worst quality, take the last url
                   sortAvailableFormatUrls(availableFormats, allFormatUrlMap, formatUrlMap)
                   def selectedUrl = formatUrlMap.entrySet().toList().last()
                   contentUrl = selectedUrl.getValue()
                   cacheKey = getCacheKey(linkUrl, selectedUrl.getKey())
               }              
               if(contentUrl != null) {
                   expiresImmediately = true
                   if(contentUrl.startsWith('http')) {
                       // http URL
                       def contentUrlParameters = [:]
                       contentUrl.split('&').each{item -> addParameter(item, contentUrlParameters, '=')}
                       if( contentUrlParameters['expire'] != null ) {   
                           //log(Long.parseLong(contentUrlParameters['expire']).toString())
                           expiryDate = new Date(Long.parseLong(contentUrlParameters['expire'])*1000)
                           expiresImmediately = false
                       }
                   } else {
                           // rtmp URL
                           def rtmpMatcher = contentUrl =~ 'rtmpe?://.*?/(.*)'
                        def app = rtmpMatcher[0][1]
                        // TODO load swf player URL from the HTML page
                           contentUrl = "$contentUrl app=$app swfUrl=http://s.ytimg.com/yt/swfbin/watch_as3-vflg0Q-LP.swf swfVfy=1"
                   }    
               }
                
                break
            }
        }    
        return new ContentURLContainer(fileType: MediaFileType.VIDEO, contentUrl: contentUrl, thumbnailUrl: thumbnailUrl, expiresOn: expiryDate, expiresImmediately: expiresImmediately, cacheKey: cacheKey)
    }
 
    def addParameter(parameterString, parameters, separator) {
        def values = parameterString.split(separator)
        if( values.length == 2 ) {    
             parameters.put(values[0], values[1])
        }
    }   
    
    def processStreamData(String urlEncodedUrlMapString, Map streamsMap ) {
        URLDecoder.decode(urlEncodedUrlMapString,'UTF-8').split(',').each{item ->
            def streamParams = [:]
            item.split('&').each{item2 -> addParameter(item2, streamParams, '=')}
            String urlKeyName = streamParams.containsKey('url') ? 'url' : 'conn'
            //String stream = URLDecoder.decode(streamParams['stream'],'UTF-8') //TODO stream is playpath
            String streamUrl = URLDecoder.decode(streamParams[urlKeyName],'UTF-8')
            String signature = streamParams['sig']
            if(signature) streamUrl = streamUrl + "&signature=" + signature
            streamsMap.put(streamParams['itag'], streamUrl )
        }
    }

    def String getCacheKey(String videoId, String qualityId) {
        "youtube_${videoId}_${qualityId}"
    }
        
    def sortAvailableFormatUrls(List formatIds, Map sourceMap, Map targetMap) {
        formatIds.each{formatId ->
            if(sourceMap.containsKey(formatId) ) {                
                 targetMap.put(formatId, sourceMap.get(formatId))
            }
        }
    }
    
    static void main(args) {
        // this is just to test
        YouTube extractor = new YouTube()
        
        assert extractor.extractorMatches( new URL("https://www.googleapis.com/youtube/v3/playlistItems?playlistId=YOUR_PLAYLIST_ID_HERE") )
        assert !extractor.extractorMatches( new URL("http://google.com/feeds/api/standardfeeds/top_rated?time=today") )
        
        WebResourceContainer container = extractor.extractItems( new URL("https://www.googleapis.com/youtube/v3/playlistItems?playlistId=PL5D6FB3CCE0053D01"), 10)
					
        println container
        ContentURLContainer result = extractor.extractUrl(container.getItems()[2], PreferredQuality.MEDIUM)
        println result
        
        
    }

}