DECLARE_EXPORT void Load::validate(Action action)
{
// Catch null operation and resource pointers
Operation *oper = getOperation();
Resource *res = getResource();
if (!oper || !res)
{
// Invalid load model
if (!oper && !res)
throw DataException("Missing operation and resource on a load");
else if (!oper)
throw DataException("Missing operation on a load on resource '"
+ res->getName() + "'");
else if (!res)
throw DataException("Missing resource on a load on operation '"
+ oper->getName() + "'");
}
// Check if a load with 1) identical resource, 2) identical operation and
// 3) overlapping effectivity dates already exists
Operation::loadlist::const_iterator i = oper->getLoads().begin();
for (; i != oper->getLoads().end(); ++i)
if (i->getResource() == res
&& i->getEffective().overlap(getEffective())
&& &*i != this)
break;
// Apply the appropriate action
switch (action)
{
case ADD:
if (i != oper->getLoads().end())
{
throw DataException("Load of '" + oper->getName() + "' and '"
+ res->getName() + "' already exists");
}
break;
case CHANGE:
throw DataException("Can't update a load");
case ADD_CHANGE:
// ADD is handled in the code after the switch statement
if (i == oper->getLoads().end()) break;
throw DataException("Can't update a load");
case REMOVE:
// This load was only used temporarily during the reading process
delete this;
if (i == oper->getLoads().end())
// Nothing to delete
throw DataException("Can't remove nonexistent load of '"
+ oper->getName() + "' and '" + res->getName() + "'");
delete &*i;
// Set a flag to make sure the level computation is triggered again
HasLevel::triggerLazyRecomputation();
return;
}
// The statements below should be executed only when a new load is created.
// Set a flag to make sure the level computation is triggered again
HasLevel::triggerLazyRecomputation();
}
void SolverMRP::solve(const Load* l, void* v)
{
// Note: This method is only called for decrease loadplans and for the leading
// load of an alternate group. See SolverMRP::checkOperation
SolverMRPdata* data = static_cast<SolverMRPdata*>(v);
unsigned int loglevel = data->getSolver()->getLogLevel();
if (data->state->q_qty >= 0.0)
{
// The loadplan is an increase in size, and the resource solver only needs
// the decreases.
data->state->a_qty = data->state->q_qty;
data->state->a_date = data->state->q_date;
return;
}
if (!l->hasAlternates() && !l->getAlternate())
{
// CASE I: It is not an alternate load.
// Delegate the answer immediately to the resource
chooseResource(l, data);
return;
}
// CASE II: It is an alternate load.
// We ask each alternate load in order of priority till we find a load
// that has a non-zero reply.
// 1) collect a list of alternates
list<const Load*> thealternates;
const Load *x = l->hasAlternates() ? l : l->getAlternate();
SearchMode search = l->getSearch();
for (Operation::loadlist::const_iterator i = l->getOperation()->getLoads().begin();
i != l->getOperation()->getLoads().end(); ++i)
if ((i->getAlternate() == x || &*i == x)
&& i->getEffective().within(data->state->q_loadplan->getDate()))
thealternates.push_back(&*i);
// 2) Sort the list
thealternates.sort(sortLoad); // @todo cpu-intensive - better is to maintain the list in the correct order
// 3) Control the planning mode
bool originalPlanningMode = data->constrainedPlanning;
data->constrainedPlanning = true;
// Don't keep track of the constraints right now
bool originalLogConstraints = data->logConstraints;
data->logConstraints = false;
// 4) Loop through all alternates or till we find a non-zero
// reply (priority search)
Date min_next_date(Date::infiniteFuture);
LoadPlan *lplan = data->state->q_loadplan;
double bestAlternateValue = DBL_MAX;
double bestAlternateQuantity = DBL_MIN;
const Load* bestAlternateSelection = NULL;
double beforeCost = data->state->a_cost;
double beforePenalty = data->state->a_penalty;
OperationPlanState originalOpplan(lplan->getOperationPlan());
double originalLoadplanQuantity = data->state->q_loadplan->getQuantity();
for (list<const Load*>::const_iterator i = thealternates.begin();
i != thealternates.end();)
{
const Load *curload = *i;
data->state->q_loadplan = lplan; // because q_loadplan can change!
// 4a) Switch to this load
if (lplan->getLoad() != curload) lplan->setLoad(curload);
lplan->getOperationPlan()->restore(originalOpplan);
data->state->q_qty = lplan->getQuantity();
data->state->q_date = lplan->getDate();
// 4b) Ask the resource
// TODO XXX Need to insert another loop here! It goes over all resources qualified for the required skill.
// The qualified resources need to be sorted based on their cost. If the cost is the same we should use a decent tie breaker, eg number of skills or number of loads.
// The first resource with the qualified skill that is available will be used.
CommandManager::Bookmark* topcommand = data->setBookmark();
if (search == PRIORITY)
curload->getResource()->solve(*this,data);
else
{
data->getSolver()->setLogLevel(0);
try {curload->getResource()->solve(*this,data);}
catch (...)
{
data->getSolver()->setLogLevel(loglevel);
// Restore the planning mode
data->constrainedPlanning = originalPlanningMode;
data->logConstraints = originalLogConstraints;
throw;
}
data->getSolver()->setLogLevel(loglevel);
}
// 4c) Evaluate the result
if (data->state->a_qty > ROUNDING_ERROR
&& lplan->getOperationPlan()->getQuantity() > 0)
{
if (search == PRIORITY)
{
// Priority search: accept any non-zero reply
// Restore the planning mode
data->constrainedPlanning = originalPlanningMode;
data->logConstraints = originalLogConstraints;
return;
}
else
{
// Other search modes: evaluate all
double deltaCost = data->state->a_cost - beforeCost;
double deltaPenalty = data->state->a_penalty - beforePenalty;
// Message
if (loglevel>1 && search != PRIORITY)
logger << indent(l->getOperation()->getLevel()) << " Operation '"
<< l->getOperation()->getName() << "' evaluates alternate '"
<< curload->getResource() << "': cost " << deltaCost
<< ", penalty " << deltaPenalty << endl;
if (deltaCost < ROUNDING_ERROR && deltaPenalty < ROUNDING_ERROR)
{
// Zero cost and zero penalty on this alternate. It won't get any better
// than this, so we accept this alternate.
if (loglevel>1)
logger << indent(l->getOperation()->getLevel()) << " Operation '"
<< l->getOperation()->getName() << "' chooses alternate '"
<< curload->getResource() << "' " << search << endl;
// Restore the planning mode
data->constrainedPlanning = originalPlanningMode;
data->logConstraints = originalLogConstraints;
return;
}
data->state->a_cost = beforeCost;
data->state->a_penalty = beforePenalty;
double val = 0.0;
switch (search)
{
case MINCOST:
val = deltaCost / lplan->getOperationPlan()->getQuantity();
break;
case MINPENALTY:
val = deltaPenalty / lplan->getOperationPlan()->getQuantity();
break;
case MINCOSTPENALTY:
val = (deltaCost + deltaPenalty) / lplan->getOperationPlan()->getQuantity();
break;
default:
LogicException("Unsupported search mode for alternate load");
}
if (val + ROUNDING_ERROR < bestAlternateValue
|| (fabs(val - bestAlternateValue) < ROUNDING_ERROR
&& lplan->getOperationPlan()->getQuantity() > bestAlternateQuantity))
{
// Found a better alternate
bestAlternateValue = val;
bestAlternateSelection = curload;
bestAlternateQuantity = lplan->getOperationPlan()->getQuantity();
}
}
}
else if (loglevel>1 && search != PRIORITY)
logger << indent(l->getOperation()->getLevel()) << " Operation '"
<< l->getOperation()->getName() << "' evaluates alternate '"
<< curload->getResource() << "': not available before "
<< data->state->a_date << endl;
// 4d) Undo the plan on the alternate
data->rollback(topcommand);
// 4e) Prepare for the next alternate
if (data->state->a_date < min_next_date)
min_next_date = data->state->a_date;
if (++i != thealternates.end() && loglevel>1 && search == PRIORITY)
logger << indent(curload->getOperation()->getLevel()) << " Alternate load switches from '"
<< curload->getResource()->getName() << "' to '"
<< (*i)->getResource()->getName() << "'" << endl;
}
// 5) Unconstrained plan: plan on the first alternate
if (!originalPlanningMode && !(search != PRIORITY && bestAlternateSelection))
{
// Switch to unconstrained planning
data->constrainedPlanning = false;
bestAlternateSelection = *(thealternates.begin());
}
// 6) Finally replan on the best alternate
if (!originalPlanningMode || (search != PRIORITY && bestAlternateSelection))
{
// Message
if (loglevel>1)
logger << indent(l->getOperation()->getLevel()) << " Operation '"
<< l->getOperation()->getName() << "' chooses alternate '"
<< bestAlternateSelection->getResource() << "' " << search << endl;
// Switch back
data->state->q_loadplan = lplan; // because q_loadplan can change!
data->state->a_cost = beforeCost;
data->state->a_penalty = beforePenalty;
if (lplan->getLoad() != bestAlternateSelection)
lplan->setLoad(bestAlternateSelection);
lplan->getOperationPlan()->restore(originalOpplan);
// TODO XXX need to restore also the selected resource with the right skill!
data->state->q_qty = lplan->getQuantity();
data->state->q_date = lplan->getDate();
bestAlternateSelection->getResource()->solve(*this,data);
// Restore the planning mode
data->constrainedPlanning = originalPlanningMode;
data->logConstraints = originalLogConstraints;
return;
}
// 7) No alternate gave a good result
data->state->a_date = min_next_date;
data->state->a_qty = 0;
// Restore the planning mode
data->constrainedPlanning = originalPlanningMode;
// Maintain the constraint list
if (originalLogConstraints)
{
const Load *primary = *(thealternates.begin());
data->planningDemand->getConstraints().push(
ProblemCapacityOverload::metadata,
primary->getResource(), originalOpplan.start, originalOpplan.end,
-originalLoadplanQuantity);
}
data->logConstraints = originalLogConstraints;
if (loglevel>1)
logger << indent(lplan->getOperationPlan()->getOperation()->getLevel()) <<
" Alternate load doesn't find supply on any alternate : "
<< data->state->a_qty << " " << data->state->a_date << endl;
}
