package mvd.jester.tests;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import mvd.jester.info.SchedulingInfo;
import mvd.jester.info.TerminationInfo;
import mvd.jester.model.DagTask;
import mvd.jester.model.SortedTaskSet;
import mvd.jester.model.SystemManagerInterface;
import mvd.jester.model.Task;
import mvd.jester.priority.PriorityManager;
import mvd.jester.priority.RateMonotonic;

/**
 * SchmidMottok
 */
public class SchmidMottok extends AbstractTest<DagTask> {

    private final Map<Task, TerminationInfo> responseTimes;
    private final PriorityManager priorityManager;
    private final TypeFunction structure;

    public SchmidMottok(TypeFunction structure, final SystemManagerInterface manager) {
        super(manager);
        this.responseTimes = new HashMap<>();
        this.priorityManager = new RateMonotonic();
        this.structure = structure;
    }

    @Override
    public PriorityManager getPriorityManager() {
        return priorityManager;
    }

    @Override
    public SchedulingInfo runSchedulabilityCheck(final SortedTaskSet<DagTask> tasks) {
        responseTimes.clear();
        for (final DagTask t : tasks) {
            final long responseTime = calculateResponseTime(tasks, t);
            responseTimes.put(t, new TerminationInfo(t.getDeadline(), responseTime));
        }

        return new SchedulingInfo(responseTimes.values());
    }

    @Override
    public String getName() {
        return "SchmidMottok" + "_" + structure.getType();
    }

    private long calculateResponseTime(final Set<DagTask> tasks, final DagTask task) {
        final long minimumWcet = task.getCriticalPath();
        long responseTime = minimumWcet;
        long previousResponseTime = 0;

        do {
            previousResponseTime = responseTime;
            double taskInterference = 0;
            for (final DagTask t : tasks) {
                if (t.getPeriod() < task.getPeriod()) {
                    final long numberOfThreads = structure.getNumberOfThreads(t);
                    for (int p = 0; p < numberOfThreads; ++p) {
                        taskInterference += Math.min(structure.getTaskInterference(t, responseTimes,
                                responseTime, p + 1), responseTime - minimumWcet + 1);
                    }
                }
            }

            taskInterference /= manager.getNumberOfProcessors();
            final double selfInterference = structure.getSelfInterference(task);

            final long totalInterference = (long) Math.floor(taskInterference + selfInterference);

            responseTime = minimumWcet + totalInterference;
        } while (previousResponseTime != responseTime);

        return responseTime;
    }

}