public SourceEnvironmentToTenantMap(EnvironmentResource[] environmentsToMigrate, TenantResource[] existingTenants)
{
var expectedTenantNames = environmentsToMigrate.Select(Conventions.BuildTenantNameFromSourceEnvironment).Distinct(StringComparer.OrdinalIgnoreCase).ToArray();
var tenants = existingTenants.Where(t => expectedTenantNames.Contains(t.Name, StringComparer.OrdinalIgnoreCase)).ToArray();
MissingTenantNames = expectedTenantNames.Except(tenants.Select(t => t.Name), StringComparer.OrdinalIgnoreCase).ToArray();
if (!MissingTenantNames.Any())
{
sourcesAndTenants = environmentsToMigrate
.Select(e => new SourceEnvironmentAndTenant(e, tenants.Single(t => string.Equals(t.Name, Conventions.BuildTenantNameFromSourceEnvironment(e), StringComparison.OrdinalIgnoreCase))))
.ToArray();
}
}