package unit;
import java.util.*;

/**
 * CiliumTest — CWE-407 benchmark for cilium-0001
 *
 * cilium-0001: Requirement.hasValue() slices.Contains(r.strValues, value)
 *   called per identity in selectorcache selections() loop → O(I × R × V)
 *
 * Model:
 *   I = number of security identities in the cache
 *   R = number of requirements in the selector
 *   V = number of values per requirement (e.g. In [ns1, ns2, ..., nsV])
 *
 * SLOW: for each identity, for each requirement, slices.Contains(strValues) → O(I × R × V)
 * FAST: strValues as map[string]struct{}, O(1) lookup → O(I × R)
 */
public class CiliumTest {

    // -------------------------------------------------------------------------
    // Data model
    // -------------------------------------------------------------------------
    static class Identity {
        final Map<String, String> labels;
        Identity(String key, String value) {
            this.labels = new HashMap<>();
            this.labels.put(key, value);
        }
    }

    static class RequirementSlow {
        final String key;
        final List<String> strValues;   // ← slice, O(n) membership
        RequirementSlow(String key, List<String> values) {
            this.key = key;
            this.strValues = values;
        }
        boolean matches(Identity id) {
            String val = id.labels.get(key);
            if (val == null) return false;
            // hasValue: slices.Contains — O(V) scan
            return strValues.contains(val);
        }
    }

    static class RequirementFast {
        final String key;
        final Set<String> strValues;    // ← map, O(1) membership
        RequirementFast(String key, List<String> values) {
            this.key = key;
            this.strValues = new HashSet<>(values);
        }
        boolean matches(Identity id) {
            String val = id.labels.get(key);
            if (val == null) return false;
            // hasValue: map.contains — O(1)
            return strValues.contains(val);
        }
    }

    // -------------------------------------------------------------------------
    // SLOW: selector cache selections() using slice-based requirements
    // -------------------------------------------------------------------------
    static long selectIdentities_slow(List<Identity> identities,
                                       List<RequirementSlow> requirements) {
        long ops = 0;
        for (Identity id : identities) {
            boolean allMatch = true;
            for (RequirementSlow req : requirements) {
                String val = id.labels.get(req.key);
                if (val == null) { allMatch = false; break; }
                // slices.Contains simulation: scan strValues
                boolean found = false;
                for (String sv : req.strValues) {
                    ops++;
                    if (sv.equals(val)) { found = true; break; }
                }
                if (!found) { allMatch = false; break; }
            }
        }
        return ops;
    }

    // -------------------------------------------------------------------------
    // FAST: selector cache selections() using map-based requirements
    // -------------------------------------------------------------------------
    static long selectIdentities_fast(List<Identity> identities,
                                       List<RequirementFast> requirements) {
        long ops = 0;
        for (Identity id : identities) {
            for (RequirementFast req : requirements) {
                String val = id.labels.get(req.key);
                if (val == null) break;
                ops++; // O(1) map lookup
                req.strValues.contains(val);
            }
        }
        return ops;
    }

    // -------------------------------------------------------------------------
    // Helpers
    // -------------------------------------------------------------------------
    static List<String> makeValues(int count, String prefix) {
        List<String> vals = new ArrayList<>(count);
        for (int i = 0; i < count; i++) vals.add(prefix + i);
        return vals;
    }

    static List<Identity> makeIdentities(int count, String key, int valueRange) {
        List<Identity> ids = new ArrayList<>(count);
        for (int i = 0; i < count; i++) {
            ids.add(new Identity(key, "ns" + (i % valueRange)));
        }
        return ids;
    }

    static void bench(String label, long sOps, long fOps) {
        System.out.printf("  %-55s slow=%9d  fast=%7d  ratio=%5.1fx%n",
                label, sOps, fOps, (double) sOps / Math.max(fOps, 1));
    }

    // -------------------------------------------------------------------------
    // Main
    // -------------------------------------------------------------------------
    public static void main(String[] args) {
        System.out.println("CiliumTest — CWE-407 cilium-0001 Requirement.hasValue linear scan");
        System.out.println();

        // --- I=1000, R=2, V=20 ---
        {
            int I = 1000, V = 20;
            String key = "k8s:io.kubernetes.pod.namespace";
            List<String> values = makeValues(V, "ns");
            List<Identity> ids = makeIdentities(I, key, V);
            List<RequirementSlow> slowReqs = List.of(new RequirementSlow(key, values));
            List<RequirementFast> fastReqs = List.of(new RequirementFast(key, values));

            long sOps = selectIdentities_slow(ids, slowReqs);
            long fOps = selectIdentities_fast(ids, fastReqs);
            bench("I=1000 R=1 V=20", sOps, fOps);
            assert sOps > fOps * 5 :
                "Expected slow >> fast, got slow=" + sOps + " fast=" + fOps;
        }

        // --- I=5000, R=2, V=50 ---
        {
            int I = 5000, V = 50;
            String key = "k8s:io.kubernetes.pod.namespace";
            List<String> values = makeValues(V, "ns");
            List<Identity> ids = makeIdentities(I, key, V);
            List<RequirementSlow> slowReqs = List.of(new RequirementSlow(key, values));
            List<RequirementFast> fastReqs = List.of(new RequirementFast(key, values));

            long sOps = selectIdentities_slow(ids, slowReqs);
            long fOps = selectIdentities_fast(ids, fastReqs);
            bench("I=5000 R=1 V=50", sOps, fOps);
            assert sOps > fOps * 10 :
                "Expected slow >> fast, got slow=" + sOps + " fast=" + fOps;
        }

        // --- I=10000, R=3, V=50 (large cluster) ---
        {
            int I = 10000, V = 50;
            String key = "k8s:io.kubernetes.pod.namespace";
            List<String> values = makeValues(V, "ns");
            List<Identity> ids = makeIdentities(I, key, V);
            List<RequirementSlow> slowReqs = new ArrayList<>();
            List<RequirementFast> fastReqs = new ArrayList<>();
            for (int r = 0; r < 3; r++) {
                slowReqs.add(new RequirementSlow(key, values));
                fastReqs.add(new RequirementFast(key, values));
            }

            long sOps = selectIdentities_slow(ids, slowReqs);
            long fOps = selectIdentities_fast(ids, fastReqs);
            bench("I=10000 R=3 V=50 (large cluster)", sOps, fOps);
            assert sOps > fOps * 20 :
                "Expected slow >> fast, got slow=" + sOps + " fast=" + fOps;
        }

        // --- I=10000, R=1, V=200 (wide In selector — worst case) ---
        {
            int I = 10000, V = 200;
            String key = "k8s:io.kubernetes.pod.namespace";
            List<String> values = makeValues(V, "ns");
            List<Identity> ids = makeIdentities(I, key, V);
            List<RequirementSlow> slowReqs = List.of(new RequirementSlow(key, values));
            List<RequirementFast> fastReqs = List.of(new RequirementFast(key, values));

            long sOps = selectIdentities_slow(ids, slowReqs);
            long fOps = selectIdentities_fast(ids, fastReqs);
            bench("I=10000 R=1 V=200 (wide In — worst case)", sOps, fOps);
            assert sOps > fOps * 50 :
                "Expected slow >> fast, got slow=" + sOps + " fast=" + fOps;
        }

        System.out.println();
        System.out.println("All assertions passed.");
    }
}