/// <summary>
/// Returns the viewing statistics for all movies.
/// ● The movies are ordered by most watched, then by release year with newer releases
/// being considered more important.
/// ● The data returned only needs to contain information from the supplied csv documents
/// and does not need to return data provided by the POST metadata endpoint.
/// </summary>
/// <returns></returns>
public async Task <string> GetStats()
{
if (_movies == null)
{
await LoadData();
}
var movieWatchDurations = await LoadStats();
var moviesStat = new List <MovieStat>();
foreach (var kv in movieWatchDurations.OrderByDescending(x => x.Value.Count))
{
var moviesById = await GetMovieById(kv.Key);
if (moviesById.Count == 0)
{
continue;
}
foreach (var movieDetails in moviesById)
{
var averageWatchDurationS = (int)(kv.Value.Sum() / (1000.0 * kv.Value.Count));
var movieStat = new MovieStat
{
MoveId = movieDetails.MoveId,
Title = movieDetails.Title,
ReleaseYear = movieDetails.ReleaseYear,
Watches = kv.Value.Count,
AverageWatchDurationS = averageWatchDurationS
};
moviesStat.Add(movieStat);
}
}
return(JsonSerializer.Serialize <List <MovieStat> >(moviesStat));
}
//private List<MovieStat> getStatsFromString()
private void populateMovieLists()
{
List <string> statsStrings = Retrieve.RetrieveData(statsFileLocation);
List <string> metaStrings = Retrieve.RetrieveData(metaFileLocation);
statsStrings.Sort(); // Sort the list so all ids are together
// metaStrings are already sorted by id and MovieID
int currentID = -1;
int numOfEntries = 0;
double sumOfMs = 0;
foreach (string statString in statsStrings)
{
int newID = 0;
bool ret_val = Int32.TryParse((statString.Split(','))[0], out newID);
if (ret_val) // We have valid values
{
double currentMs = Convert.ToDouble((statString.Split(','))[1]);
if ((newID != currentID) && (numOfEntries > 0)) // a) we can't divide by zero b) we only want to add a stat after we got an entry
{
// Argument is int, as the average watch time, shouldn't be more than the movies duration
MovieStat aStat = new MovieStat(currentID, (int)(sumOfMs / numOfEntries), numOfEntries);
moviesWithStat.Add(aStat);
numOfEntries = 0;
sumOfMs = currentMs;
}
else
{
sumOfMs += currentMs; // Add entry to the sum of stats
numOfEntries++;
}
currentID = newID; // Set the id of the new statString element
} // Else this line has headers or invalid text
}
// There should be one last item we haven't inserted to the list
if (numOfEntries != 0)
{
// Argument is int, as the average watch time, shouldn't be more than the movies duration
MovieStat aStat = new MovieStat(currentID, (int)(sumOfMs / numOfEntries), numOfEntries);
moviesWithStat.Add(aStat);
}
MovieMeta previousMeta = new MovieMeta();
// Now we have to retrieve the metaData and use them to populate the missing
// data in the statsList
foreach (string meta in metaStrings)
{
string[] metaArray = meta.Split(',');
// We will not consider metadata with missing values
int newID, tempYear = 0;
bool ret_id = Int32.TryParse(metaArray[0], out newID); // every valid data line, should start with an id
bool ret_year = Int32.TryParse(metaArray[5], out tempYear); // every valid data line, should start with an id
if (ret_id && ret_year)
{
if (metaArray.Length > 5)
{
// MetaArray[0] should be the file id
MovieMeta metaItem = new MovieMeta(Convert.ToInt32(metaArray[1]), metaArray[2], metaArray[3], metaArray[4], metaArray[5]);
// The first item as the previous and the current one
if (previousMeta == null)
{
previousMeta = metaItem;
}
else
// Make sure there are no empty values
if (metaItem.movieId != 0 && metaItem.title != "" && metaItem.language != "" && metaItem.duration != "" && metaItem.releaseYear != 0)
{
// We have to take only the latest (higher ID number) of the same metadata
// as "same", we consider metadata that have the same movieID and Language parameters
if ((metaItem.movieId != previousMeta.movieId) || (metaItem.language != previousMeta.language))
{// We have a new meta data that needs to be stored,
// previousMeta, have the latest values of similar metas, since the list ordered by id and movieID
moviesWithMeta.Add(metaItem);
previousMeta = metaItem; // Update the previous meta as we have added it to the list
// Add the missing data in the stats list objects
var obj = moviesWithStat.FirstOrDefault(statList => statList.movieId == metaItem.movieId);
// obj is a reference type like the MovieStat inside the list so, the above assignment is a reference copy
// thus, any change in the obj values, will be a change of the values inside the list...
if (obj != null) // There might extra movieIDs that do not exist in the metadata file
{
obj.title = metaItem.title;
obj.releaseYear = metaItem.releaseYear;
}
}
}
}
} // Else, this line had no valid data, skip...
}
}
