public static List <Phone> RemoveDuplicates(PhoneCollection collection)
{
// Finds the earliest date in the collection of phones
var start = collection.Phones
.Min(i => i.Date);
// Finds the latest date in the collection of phones
var end = collection.Phones
.Max(i => i.Date);
if (start == end)
{
throw new Exception("Pre-processing exception: Collection's start and end date are the same.");
}
if (start > end)
{
throw new Exception("Pre-processing exception: Collection's end date is earlier than the start date.");
}
// Checks if all phones in collection have the same brand and model.
if (DataAuditing.HasConsistentBranding(collection.Phones))
{
// Loops - month by month - through all dates from the collection's beginning to the end.
for (var date = start; date < end; date = date.AddMonths(1))
{
if (collection.ContainsDate(date))
{
var occurancesOfItem = collection.Phones
.Where(i => i.Date.Month == date.Month)
.Where(i => i.Date.Year == date.Year);
if (occurancesOfItem.Count() > 1)
{
// Retrieves current date
DateTime currentDate = new DateTime(date.Year, date.Month, 1);
// Calculates the average price for items with the same month and year
var averagePrice = occurancesOfItem
.Select(i => i.Price)
.Average();
// Remove all phones
collection.Phones.RemoveAll(x => x.Date.Month == date.Month && x.Date.Year == date.Year);
collection.AddItem(collection.Phones[0].Brand,
collection.Phones[0].Model,
currentDate,
averagePrice);
}
}
}
}
collection.Phones.Sort((x, y) => DateTime.Compare(x.Date, y.Date));
return(collection.Phones);
}
public static List <Phone> FillGaps(PhoneCollection collection)
{
// Finds the earliest date in the collection of phones
var start = collection.Phones
.Min(i => i.Date);
// Finds the latest date in the collection of phones
var end = collection.Phones
.Max(i => i.Date);
if (start == end)
{
throw new Exception("Pre-processing exception: Collection's start and end date are the same.");
}
if (start > end)
{
throw new Exception("Pre-processing exception: Collection's end date is earlier than the start date.");
}
//collection.Phones.RemoveAll(x => x.Date.Month == 3);
//collection.Phones.RemoveAll(x => x.Date.Month == 4);
// Checks if all phones in collection have the same brand and model.
if (DataAuditing.HasConsistentBranding(collection.Phones))
{
// Loops - month by month - through all dates from the collection's beginning to the end.
for (var date = start; date < end; date = date.AddMonths(1))
{
if (collection.ContainsDate(date) == false)
{
DateTime currentDate = new DateTime(date.Year, date.Month, 1);
collection.AddItem(collection.Phones[0].Brand,
collection.Phones[0].Model,
currentDate,
GenerateSuggestedPrice(collection.Phones, currentDate));
}
}
}
// Sort all phones in ascending order by Datetime
collection.Phones.Sort((x, y) => DateTime.Compare(x.Date, y.Date));
return(collection.Phones);
}