package unit;
import java.util.*;

/**
 * JamiDaemonTest — CWE-407 benchmark
 *
 * Defects:
 *   0001: std::find on replies vector O(n) per git commit in conversation history load
 *         (conversation.cpp:832, :837)
 *   0002: std::find (algorithm) on std::set<string>::iterator — bypasses O(log n) set.find()
 *         (conversation_module.cpp:2341, :2501, :2797)
 */
public class JamiDaemonTest {

    static void bench(String label, Runnable slow, Runnable fast, long sOps, long fOps) {
        slow.run(); fast.run();
        long t0 = System.nanoTime(); slow.run(); long sMs = (System.nanoTime()-t0)/1_000_000;
        long t1 = System.nanoTime(); fast.run(); long fMs = (System.nanoTime()-t1)/1_000_000;
        double r = fOps > 0 ? (double)sOps/fOps : 0;
        System.out.printf("  %-56s  slow:%4dms (%,d ops)  fast:%4dms (%,d ops)  speedup:%.0fx%n",
                label, sMs, sOps, fMs, fOps, r);
    }

    // -------------------------------------------------------------------------
    // Defect 0001: replies is vector<string>, std::find used per commit
    // Models the emplaceCb called once per git commit in loadMessages()
    // C = commits, R = reply-chain IDs tracked at peak
    // -------------------------------------------------------------------------
    static long slowRepliesLoad(int commits, int maxReplies) {
        List<String> replies = new ArrayList<>();
        long ops = 0;
        for (int i = 0; i < commits; i++) {
            String replyTo = "reply-" + (i % maxReplies);
            // std::find on replies vector: O(R)
            boolean found = false;
            for (String r : replies) { ops++; if (r.equals(replyTo)) { found = true; break; } }
            if (!found) replies.add(replyTo);

            String msgId = "msg-" + i;
            // second std::find: O(R)
            for (int j = 0; j < replies.size(); j++) {
                ops++;
                if (replies.get(j).equals(msgId)) { replies.remove(j); break; }
            }
        }
        return ops;
    }

    static long fastRepliesLoad(int commits, int maxReplies) {
        Set<String> replies = new HashSet<>();
        long ops = 0;
        for (int i = 0; i < commits; i++) {
            String replyTo = "reply-" + (i % maxReplies);
            ops++;
            replies.add(replyTo);                  // O(1) insert (dedup automatic)

            String msgId = "msg-" + i;
            ops++;
            replies.remove(msgId);                 // O(1) remove
        }
        return ops;
    }

    // -------------------------------------------------------------------------
    // Defect 0002: std::find on std::set instead of set.find()
    // Models needsSyncingWith() — loop over N conversations, each with M members
    // -------------------------------------------------------------------------
    static long slowSetFind(List<Set<String>> memberSets, String target) {
        long ops = 0;
        for (Set<String> members : memberSets) {
            // std::find degrades to O(M) linear scan on set iterators
            for (String m : members) {
                ops++;
                if (m.equals(target)) break;
            }
        }
        return ops;
    }

    static long fastSetFind(List<Set<String>> memberSets, String target) {
        long ops = 0;
        for (Set<String> members : memberSets) {
            ops++;
            members.contains(target);              // O(1) — uses set's own find
        }
        return ops;
    }

    public static void main(String[] args) {
        System.out.println("JamiDaemonTest — CWE-407");

        final int C = 2000;     // commits in conversation history
        final int R = 300;      // distinct reply-chain IDs
        final int N = 500;      // conversations in needsSyncingWith
        final int M = 50;       // members per conversation

        // Build data for defect 0002
        List<Set<String>> memberSets = new ArrayList<>(N);
        for (int i = 0; i < N; i++) {
            Set<String> s = new TreeSet<>();           // TreeSet ~ std::set ordering
            for (int j = 0; j < M; j++) s.add("uri-" + i + "-" + j);
            memberSets.add(s);
        }
        String target = "uri-250-25";

        System.out.println("\n  [0001] replies vector std::find per commit (C=" + C + ", R=" + R + ")");
        bench("0001 replies vector.find vs unordered_set.find",
            () -> slowRepliesLoad(C, R),
            () -> fastRepliesLoad(C, R),
            (long) C * R / 2,   // avg scan depth ~R/2
            C * 2);             // 2 O(1) ops per commit

        System.out.println("\n  [0002] std::find on set vs set.count() per conversation (N=" + N + ", M=" + M + ")");
        bench("0002 set linear-scan via iterator vs set.contains()",
            () -> slowSetFind(memberSets, target),
            () -> fastSetFind(memberSets, target),
            (long) N * M,
            N);

        // Assertions
        int pass = 0, total = 2;

        long slow0001 = slowRepliesLoad(C, R);
        long fast0001 = fastRepliesLoad(C, R);
        if (slow0001 > fast0001 * 10) { pass++; System.out.println("  PASS 0001: slow ops >> fast ops (ratio ~" + slow0001/fast0001 + "x)"); }
        else System.out.println("  FAIL 0001: slow=" + slow0001 + " fast=" + fast0001);

        long slow0002 = slowSetFind(memberSets, target);
        long fast0002 = fastSetFind(memberSets, target);
        if (slow0002 > fast0002 * (M / 2)) { pass++; System.out.println("  PASS 0002: slow ops >> fast ops (ratio ~" + slow0002/fast0002 + "x)"); }
        else System.out.println("  FAIL 0002: slow=" + slow0002 + " fast=" + fast0002);

        System.out.printf("%n%d/%d PASS%n", pass, total);
        if (pass < total) System.exit(1);
    }
}