/// <summary>
/// Resolve effective setting within the purpose for the specified entity
/// </summary>
/// <param name="entity">Entity to for which settings are to be resolved</param>
/// <param name="purpose">The purpose of the settings which are to be resolved</param>
/// <param name="name">Name of the setting for the specified entity and purpose</param>
/// <returns>Effective setting for the specified entity, purpose, and name</returns>
/// <exception cref="ArgumentException">One of the specified arguments fail validation</exception>
/// <exception cref="UnknownEntityType">Specified entity type is not known within settings schema</exception>
/// <exception cref="UnknownSetting">Specified setting name is not known within settings schema</exception>
public Setting ResolveSetting(EntityIdentifier entity, string purpose, string name)
{
#region input validation
ValidateEntityIdentifier(entity);
if (string.IsNullOrWhiteSpace(name))
{
throw new ArgumentException("Value cannot be null or whitespace.", nameof(name));
}
#endregion
#region input clean-up
entity = Normalize(entity);
purpose = NormalizePurposeName(purpose);
name = name.Trim();
#endregion
IEntityType entityType = _settingsSchema.GetEntityType(entity.Type);
/*
* An exception should be thrown if entity-type does not exist, e.g. incorrect or has been removed from schema,
* to alert developer of usage of removed/unknown entity-type
*/
if (entityType == null)
{
throw new UnknownEntityType();
}
IEnumerable <SettingDefinition> settingDefinitions = entityType.GetSettings(purpose, name);
SettingDefinition settingDefinition = settingDefinitions.FirstOrDefault();
/*
* An exception should be thrown if setting definition does not exist, e.g. incorrect or has been removed from schema,
* to alert developer of usage of removed/unknown setting
*/
if (settingDefinition == null)
{
throw new UnknownSetting();
}
Setting setting = _settingStore.GetSetting(entity, purpose, name);
return(ResolveSetting(purpose, name, setting, settingDefinition));
}
private static Setting ResolveSetting(string purpose, string name, Setting setting, SettingDefinition settingDefinition)
{
if (setting != null)
{
// override stored setting default value with 'current' setting definition default value
if (setting.ValueSource.Type == SettingValueSourceType.Default)
{
if (settingDefinition.HasDefaultValue)
{
setting.Value = settingDefinition.DefaultValue;
}
}
return(setting);
}
// if no stored setting is found, return setting based on 'default' specified in SettingDefinition
if (settingDefinition.HasDefaultValue)
{
return new Setting
{
Purpose = purpose,
Name = settingDefinition.Name,
Value = settingDefinition.DefaultValue,
ValueSource = new SettingValueSource
{
Type = SettingValueSourceType.Default
}
}
}
;
// no stored setting found and setting definition has no 'default' value
return(null);
}