/// <summary>
/// Returns whether or not another <see cref="DateTimeSpan"/> in any way overlaps this
/// <see cref="DateTimeSpan"/>.
/// </summary>
/// <param name="span">The DateTimeSpan to test for any overlaps.</param>
public bool Overlaps(DateTimeSpan span)
{
return(span.Equals(this) ||
(span.Start < End && span.End == End) ||
(span.End > Start && span.Start == Start) ||
(span.Contains(Start) && Contains(span.End)) ||
(span.Contains(End) && Contains(span.Start)) ||
(span.Contains(Start) && span.Contains(End)) ||
(Contains(span.Start) && Contains(span.End)));
}
/// <summary>
/// Tries to find and return all items of a product type during a timespan that aren't reserved.
/// </summary>
/// <param name="productId">The product type whose items to return.</param>
/// <param name="span">The time period to test for unreserved items.</param>
/// <returns>A subset of all items of the given product type, or null if the product type has no items.</returns>
private List <ProductItem> Core_GetUnreservedItems(string productId, DateTimeSpan span)
{
List <ProductItem> items = Core_getProductItems(new string[] { productId })[productId].ToList();
if (!items.Any())
{
return(null);
}
var condition = new MySqlConditionBuilder();
condition.NewGroup();
foreach (var item in items)
{
condition.Or()
.Column("product_item")
.Equals(item.Id, item.GetIndex("PRIMARY").Columns[0].Type);
}
condition.EndGroup();
condition.And()
.Column("end")
.GreaterThanOrEqual()
.Operand(span.Start, MySqlDbType.DateTime);
condition.And()
.Column("start")
.LessThanOrEqual()
.Operand(span.End, MySqlDbType.DateTime);
List <LoanItem> loans = Connection.Select <LoanItem>(condition).ToList();
foreach (var loan in loans)
{
if (!items.Any(x => x.Id == loan.ProductItem))
{
continue;
}
var loanSpan = new DateTimeSpan(loan.Start, loan.End);
if (span.Overlaps(loanSpan))
{
items.Remove(items.First(x => x.Id == loan.ProductItem));
}
}
return(items);
}
public JObject resizeLoan(JObject request)
{
//Get arguments
request.TryGetValue("loanId", out JToken loanItemID);
request.TryGetValue("start", out JToken requestStart);
request.TryGetValue("end", out JToken requestEnd);
// Verify the arguments
List <string> failedVerifications = new List <string>();
if (loanItemID == null || loanItemID.Type != JTokenType.Integer)
{
failedVerifications.Add("loanId");
}
if (requestStart == null || !(requestStart.Type == JTokenType.String || requestStart.Type == JTokenType.Date))
{
failedVerifications.Add("start");
}
if (requestEnd == null || !(requestEnd.Type == JTokenType.String || requestEnd.Type == JTokenType.Date))
{
failedVerifications.Add("end");
}
if (failedVerifications.Any())
{
return(Templates.InvalidArguments(failedVerifications.ToArray()));
}
// Parse arguments
DateTime start;
DateTime end;
string loanID = loanItemID.ToString();
try { start = DateTime.Parse(requestStart.ToString()); } catch (Exception) { return(Templates.InvalidArgument("Unable to parse 'start'")); }
try { end = DateTime.Parse(requestEnd.ToString()); } catch (Exception) { return(Templates.InvalidArgument("Unable to parse 'end'")); }
if (end < start)
{
return(Templates.InvalidArguments("'end' must come after 'start'"));
}
DateTimeSpan newLoanSpan = new DateTimeSpan(start, end);
if (newLoanSpan.Start < DateTime.Now.Date)
{
return(Templates.InvalidArgument("'start' may not be set earlier than today."));
}
if (newLoanSpan.Duration > MaxLoanDuration)
{
return(Templates.InvalidArgument($"Duration of the loan may not exceed {MaxLoanDuration.Days} days."));
}
// Build a condition to get the specific loan
var condition = new MySqlConditionBuilder();
// Automatically limit results to current user only if their permission is User
if (CurrentUser.Permission <= UserPermission.User)
{
condition.And().Column("user").Equals(CurrentUser.Username, MySqlDbType.String);
}
condition.And().Column("id").Equals(loanID, MySqlDbType.Int32);
//Get the specified loanItem if it exists. If it doesn't, throw an error.
LoanItem oldLoan = Connection.Select <LoanItem>(condition).FirstOrDefault();
if (oldLoan == null)
{
return(Templates.NoSuchLoan(loanID));
}
// Return a loanExpired template if the loan has already ended
if (oldLoan.End < DateTime.Now)
{
return(Templates.LoanExpired());
}
if (oldLoan.Start < DateTime.Now && oldLoan.Start != start)
{
return(Templates.LoanAlreadyStarted());
}
// Build condition
condition = new MySqlConditionBuilder()
.Column("product_item")
.Equals(oldLoan.ProductItem, MySqlDbType.Int32);
// Select only relevant loans
condition.And().Column("end").GreaterThanOrEqual().Operand(start, MySqlDbType.DateTime);
condition.And().Column("start").LessThanOrEqual().Operand(end, MySqlDbType.DateTime);
//Get all loanItems for this loan's product_item.
var loans = Connection.Select <LoanItem>(condition).ToList();
//Check for conflicting loanItems
bool canResize = true;
foreach (var loan in loans)
{
var loanSpan = new DateTimeSpan(loan.Start, loan.End);
if (newLoanSpan.Overlaps(loanSpan))
{
canResize = false;
break;
}
}
//Create response
var responseData = new JObject();
JObject response = new JObject()
{
{ "reason", null },
{ "responseData", responseData }
};
if (canResize)
{
// Update loan
oldLoan.Start = start;
oldLoan.End = end;
Connection.Update(oldLoan);
}
else if (oldLoan.IsAcquired && !canResize) // If loan is not eligible for a item reassignment
{
return(Templates.LoanResizeFailed());
}
else // If the loan is eligible for an item reassignment
{
// Try to retrieve a list of unreserved equivalent products
var unreservedAlts = Core_GetUnreservedItems(oldLoan.GetProductItem(Connection).ProductId, newLoanSpan);
if (unreservedAlts == null) // Normally this value should not be able to be null. This block is just a failsafe that adds context.
{
throw new InvalidOperationException("Expected type of 'unreservedAlts' is List, but nullreference was found.");
}
if (!unreservedAlts.Any())
{
Log.Error("Failed at line 107");
return(Templates.LoanResizeFailed());
}
// Update loan
oldLoan.ProductItem = unreservedAlts.First().Id.Value;
oldLoan.Start = start;
oldLoan.End = end;
Connection.Update(oldLoan);
// Return new data in response and add message for context
responseData["product_item"] = oldLoan.ProductItem;
response["message"] = "Loan has been reassigned.";
}
return(response);
}
public JObject addLoan(JObject request)
{
//Get arguments
request.TryGetValue("productId", out JToken requestProductId);
request.TryGetValue("start", out JToken requestStart);
request.TryGetValue("end", out JToken requestEnd);
// Verify the arguments
List <string> failedVerifications = new List <string>();
if (requestProductId == null || requestProductId.Type != JTokenType.String)
{
failedVerifications.Add("productID");
}
if (requestStart == null || !(requestStart.Type == JTokenType.String || requestStart.Type == JTokenType.Date))
{
failedVerifications.Add("start");
}
if (requestEnd == null || !(requestEnd.Type == JTokenType.String || requestEnd.Type == JTokenType.Date))
{
failedVerifications.Add("end");
}
if (failedVerifications.Any())
{
return(Templates.InvalidArguments(failedVerifications.ToArray()));
}
// Parse arguments
DateTime start;
DateTime end;
string productId = requestProductId.ToString();
try { start = DateTime.Parse(requestStart.ToString()); }
catch (Exception) { return(Templates.InvalidArgument("Unable to parse 'start'")); }
try { end = DateTime.Parse(requestEnd.ToString()); }
catch (Exception) { return(Templates.InvalidArgument("Unable to parse 'end'")); }
if (end < start)
{
return(Templates.InvalidArguments("'end' must come after 'start'"));
}
var newLoanSpan = new DateTimeSpan(start, end);
if (newLoanSpan.Start < DateTime.Now.Date)
{
return(Templates.InvalidArgument("'start' may not be set earlier than today."));
}
if (newLoanSpan.Duration > MaxLoanDuration)
{
return(Templates.InvalidArgument($"Duration of the loan may not exceed {MaxLoanDuration.Days} days."));
}
// Get an unreserved product item
ProductItem item;
try {
item = Core_GetUnreservedItems(productId, newLoanSpan).FirstOrDefault();
} catch (Exception) {
return(Templates.NoItemsForProduct(productId));
}
if (item == null)
{
return(Templates.NoItemsForProduct($"Product '{productId}' has no items available during this time."));
}
var loan = new LoanItem(null, CurrentUser.Username, item.Id.Value, start, end);
Connection.Upload(loan);
//Create response
JObject response = new JObject()
{
{ "reason", null },
{ "responseData", new JObject()
{
{ "loanId", loan.Id },
{ "productItem", item.Id }
} }
};
return(response);
}
public JObject getProductAvailability(JObject request)
{
//Get arguments
request.TryGetValue("products", out JToken productValue);
if (productValue == null || (productValue.Type != JTokenType.String && productValue.Type != JTokenType.Array))
{
return(Templates.MissingArguments("statType"));
}
//Parse arguments
List <string> productIDs = new List <string>();
if (productValue.Type == JTokenType.String)
{
//TODO Allow * to be used as value, selecting all products
productIDs.Add(productValue.ToObject <string>());
}
else if (productValue.Type == JTokenType.Array)
{
productIDs = productValue.ToObject <List <string> >();
}
// Build condition that matches all relevant productItems and get said productItems
// The lookup groups the productItems and loanItems to a single product id.
var condition = new MySqlConditionBuilder("product", MySqlDbType.String, productIDs.ToArray());
var productItemsArray = Connection.Select <ProductItem>(condition).ToArray();
var productItems = productItemsArray.ToLookup(x => x.ProductId);
// Build condition that matches all relevand loanItems and get said loanItems
condition = new MySqlConditionBuilder("product_item", MySqlDbType.Int32, productItemsArray.Select(x => x.Id.Value).Cast <object>().ToArray());
var loanItems = Connection.Select <LoanItem>(condition).ToLookup(x => productItemsArray.First(y => y.Id == x.ProductItem).ProductId);
// DateTimeSpan representing now->midnight for filtering relevant loans
DateTimeSpan today = new DateTimeSpan(DateTime.Now, DateTime.Now.Date.AddDays(1));
// Build response data
var responseData = new JObject();
foreach (var productID in productIDs)
{
var items = productItems[productID];
var loans = loanItems[productID];
var relevantLoans = loans.Where(x => today.Overlaps(x.Start, x.End)).ToArray();
var entry = new JObject()
{
{ "total", items.Count() },
{ "totalReservations", loans.Count() },
{ "reservations", relevantLoans.Length },
{ "loanedOut", relevantLoans.Count(x => x.IsAcquired) },
{ "inStock", items.Count() - relevantLoans.Count(x => x.IsAcquired) },
{ "available", items.Count() - relevantLoans.Length }
};
responseData.Add(productID, entry);
}
//Return response
return(new JObject()
{
{ "reason", null },
{ "responseData", responseData }
});
}
public bool Equals(DateTimeSpan span) => span.Start == Start && span.End == End;
public JObject getUnavailableDates(JObject request)
{
// Get arguments
request.TryGetValue("productId", out JToken requestProductId);
request.TryGetValue("start", out JToken requestStart);
request.TryGetValue("end", out JToken requestEnd);
// Verify arguments
List <string> failedVerifications = new List <string>();
if (requestProductId == null || requestProductId.Type != JTokenType.String)
{
return(Templates.InvalidArgument("productId"));
}
if (requestStart == null)
{
return(Templates.InvalidArgument("start"));
}
if (requestEnd == null)
{
return(Templates.InvalidArgument("end"));
}
if (failedVerifications.Any())
{
return(Templates.InvalidArguments(failedVerifications.ToArray()));
}
// Parse arguments
DateTime start;
DateTime end;
try { start = requestStart == null ? new DateTime() : DateTime.Parse(requestStart.ToString()); }
catch (Exception) { return(Templates.InvalidArgument("Unable to parse 'start'")); }
try { end = requestEnd == null ? new DateTime() : DateTime.Parse(requestEnd.ToString()); }
catch (Exception) { return(Templates.InvalidArgument("Unable to parse 'end'")); }
var range = new DateTimeSpan(start, end);
if (range.Duration.Days > 122)
{
return(Templates.InvalidArgument("start and end may not be more than 122 days apart."));
}
// Get all items
var condition = new MySqlConditionBuilder("product", MySqlDbType.String, requestProductId.ToString());
var productItems = Connection.Select <ProductItem>(condition).ToArray();
// Return empty response if no items were found
if (!productItems.Any())
{
return new JObject()
{
{ "reason", null },
{ "responseData", new JArray() }
}
}
;
// Get all loans within the specified range
condition = new MySqlConditionBuilder("product_item", MySqlDbType.Int32, productItems.Select(x => x.Id).Cast <object>().ToArray());
condition.And()
.Column("end")
.GreaterThanOrEqual()
.Operand(range.Start, MySqlDbType.DateTime);
condition.And()
.Column("start")
.LessThanOrEqual()
.Operand(range.End, MySqlDbType.DateTime);
var loanItems = Connection.Select <LoanItem>(condition).ToArray();
// No idea if this is the most efficient way, but it basically iterates
// through all dates of a loan and slaps them in a cache. If the cache
// already contains the date, it increases the counter.
// If the counter is larger or equal to the total amount of items, we
// consider that date unavailable.
var dateCache = new Dictionary <DateTime, int>();
foreach (var loan in loanItems)
{
while (loan.Start < loan.End)
{
if (loan.Start < range.Start)
{
loan.Start = loan.Start.AddDays(1);
continue;
}
if (loan.End > range.End)
{
break;
}
if (dateCache.ContainsKey(loan.Start))
{
dateCache[loan.Start]++;
}
else
{
dateCache[loan.Start] = 1;
}
loan.Start = loan.Start.AddDays(1);
}
}
// Build base response
var responseData = new JArray();
JObject response = new JObject()
{
{ "reason", null },
{ "responseData", responseData }
};
// Add all dates with an amount of loans greater or equal to the max available items
foreach ((DateTime date, int count) in dateCache)
{
if (count >= productItems.Length)
{
responseData.Add((long)(date.ToUniversalTime() - Epoch).TotalMilliseconds);
}
}
return(response);
}
}
