/// <summary>
/// Determines if a transition exists between the <paramref name="fromState" /> and
/// the <paramref name="toState" /> states for the specified <paramref name="user" />.
/// </summary>
/// <param name="source">The transitions.</param>
/// <param name="user">The user.</param>
/// <param name="fromState">The From state.</param>
/// <param name="toState">The To state.</param>
/// <returns>
/// Returns a <see cref="bool" /> representing <c>true</c> if there exists a transition; otherwise, <c>false</c>.
/// </returns>
/// <exception cref="ArgumentNullException">
/// user
/// or
/// fromState
/// or
/// toState
/// </exception>
public static bool IsValidTransition(this IMMPxTransition source, IMMPxUser user, IMMPxState fromState, IMMPxState toState)
{
if (source == null)
{
return(false);
}
if (user == null)
{
throw new ArgumentNullException("user");
}
if (fromState == null)
{
throw new ArgumentNullException("fromState");
}
if (toState == null)
{
throw new ArgumentNullException("toState");
}
// Compare the from and to states from the enumerations.
if (source.FromStates.Contains(fromState) && source.ToStates.Contains(toState))
{
// Found a transition with matching To/From states, now check to see
// if the user has the proper role assigned to run the transition.
if (user.AnyRoleForTransition(source))
{
return(true);
}
}
return(false);
}
/// <summary>
/// Creates an <see cref="IEnumerable{T}" /> from an <see cref="IMMPxTransition" />
/// </summary>
/// <param name="source">An <see cref="IMMPxTransition" /> to create an <see cref="IEnumerable{T}" /> from.</param>
/// <returns>An <see cref="IEnumerable{T}" /> that contains the fields from the input source.</returns>
public static IEnumerable <IMMPxTransition> AsEnumerable(this IMMEnumPxTransition source)
{
if (source != null)
{
source.Reset();
IMMPxTransition transition = source.Next();
while (transition != null)
{
yield return(transition);
transition = source.Next();
}
}
}
/// <summary>
/// Determines whether the given <paramref name="source" /> has at least one matching
/// role for the <paramref name="transition" />.
/// </summary>
/// <param name="source">The user.</param>
/// <param name="transition">The transition.</param>
/// <returns>
/// <c>true</c> if the user has at least one matching role with the transition; otherwise, <c>false</c>.
/// </returns>
/// <exception cref="ArgumentNullException">transition</exception>
public static bool AnyRoleForTransition(this IMMPxUser source, IMMPxTransition transition)
{
if (source == null)
{
return(false);
}
if (transition == null)
{
throw new ArgumentNullException("transition");
}
foreach (var userRole in source.Roles.AsEnumerable())
{
foreach (var transitionRole in transition.Roles.AsEnumerable())
{
if (userRole == transitionRole)
{
return(true);
}
}
}
return(false);
}
