/// <summary>
/// Aggregates one or more recipes into a set of aggregated ingredients. This is normally used to create a list of items needed to buy for multiple recipes without having to create a shopping list.
/// </summary>
/// <param name="recipeIds">A list of recipe IDs to aggregate.</param>
/// <returns>A list of IngredientAggregation objects, one per unique ingredient in the set of recipes</returns>
public virtual IList <IngredientAggregation> AggregateRecipes(params Guid[] recipeIds)
{
using (InitLock.ReadLock())
{
var ings = new Dictionary <Guid, IngredientAggregation>(); //List of all ingredients and total usage
foreach (var id in recipeIds)
{
//Lookup ingredient through modeler cache
var rNode = modeler.FindRecipe(id);
if (rNode == null) //Our cache is out of date, skip this result
{
continue;
}
foreach (var usage in rNode.Ingredients)
{
var ingId = usage.Ingredient.IngredientId;
var ingName = ingParser.GetIngredientById(ingId);
var ing = new Ingredient(ingId, ingName);
ing.ConversionType = usage.Ingredient.ConvType;
IngredientAggregation agg;
if (!ings.TryGetValue(ingId, out agg))
{
ings.Add(ingId, agg = new IngredientAggregation(ing)
{
Amount = new Amount(0, usage.Unit)
});
}
//TODO: If usage.Unit is different than agg.Amount.Unit then we have a problem, throw an exception if that happens?
if (agg.Amount == null) //This aggregation contains an empty amount, so we can't aggregate
{
continue;
}
else if (!usage.Amt.HasValue) //This amount is null, cancel aggregation
{
agg.Amount = null;
}
else
{
agg.Amount += usage.Amt.Value;
}
}
}
return(ings.Values.ToList());
}
}
/// <summary>
/// Converts a usage of an ingredient within a recipe to an IngredientAggregation object, suitable for aggregating with other usages of the same ingredient.
/// </summary>
/// <param name="usage">An IngredientUsage object, usually from a recipe.</param>
/// <returns>An IngredientAggregation object, usually to be combined with other uses of that ingredient to form a shopping list.</returns>
public virtual IngredientAggregation ConvertIngredientUsage(IngredientUsage usage)
{
//TODO: Does this method need to be part of the context? Perhaps IngredientUsage should have a method to convert to an aggregation
var ing = ReadIngredient(usage.Ingredient.Id);
if (ing == null)
{
throw new IngredientNotFoundException();
}
var a = new IngredientAggregation(ing);
a.AddUsage(usage);
return(a);
}
