private Dictionary <string, int> GetCountriesWithTheBiggestChange(Covid19Stats stats, int count)
{
var countryNames = stats.Locations
.GroupBy(p => p.Country)
.Select(p => p.Key)
.ToList();
var mergedData = countryNames
.Select(name => new
{
Country = name,
Data = GetMergedData(stats, name)
})
.ToList();
return(mergedData
.Select(p => new
{
Country = p.Country,
Change = GetChange(p.Data.First().Value, p.Data)
})
.OrderByDescending(p => p.Change)
.Take(count)
.ToDictionary(p => p.Country, p => p.Change));
}
private async Task <Covid19Stats> GetStatsAsync(CancellationToken cancellationToken)
{
return(await _memoryCache.GetOrCreateAsync(nameof(Covid19Stats), async entry => {
Covid19Stats stats = await _httpClient.GetFromJsonAsync <Covid19Stats>(URL, cancellationToken).ConfigureAwait(false);
entry.AbsoluteExpirationRelativeToNow = TimeSpan.FromSeconds(10);
return stats;
}));
}
private Dictionary <DateTime, int> GetMergedData(Covid19Stats stats, string country = null)
{
return(stats.Locations
.AsQueryable()
.WhereIf(country != null, p => p.Country == country)
.SelectMany(p => p.History)
.GroupBy(p => p.Key)
.Select(p => new KeyValuePair <DateTime, int>(p.Key, p.Sum(q => q.Value)))
.OrderByDescending(p => p.Key)
.ToDictionary(p => p.Key, p => p.Value));
}
private int GetChange(int latest, Covid19Stats stats)
{
return(latest - stats.Locations
.Select(p =>
p.History
.OrderByDescending(q => q.Key)
.Skip(1)
.First())
.OrderByDescending(p => p.Key)
.Sum(p => p.Value));
}
public async Task <Covid19Numbers> GetJakartaNumbersAsync(CancellationToken cancellationToken)
{
Covid19Stats stats = await GetStatsAsync(cancellationToken).ConfigureAwait(false);
return(stats.Regions.Single(region => region.Name == "DKI Jakarta").Numbers);
}
public async Task <Covid19Numbers> GetIndonesiaNumbersAsync(CancellationToken cancellationToken)
{
Covid19Stats stats = await GetStatsAsync(cancellationToken).ConfigureAwait(false);
return(stats.Numbers);
}