import java.util.*;

/**
 * CWE-407 unit test for HAProxy http_ana.c defect.
 *
 * haproxy-0001: src/http_ana.c http_manage_client_side_cookies()
 *   while (srv) { if memcmp(val_beg, srv->cookie, ...) } — O(S) linked-list
 *   walk per HTTP request to match a cookie value to a backend server.
 *   Fix: build struct eb_root cookies_tree at config-time (same as cfgdiag.c
 *   already does for diagnostic purposes); use ebis_lookup() for O(log S) lookup.
 */
public class HaproxyTest {

    // Simulate defect: O(S) linked-list walk per request
    static String cookieLookup_list(List<String[]> servers, String cookieVal) {
        // servers: list of {name, cookie}
        for (String[] srv : servers) {              // O(S) — defect
            if (srv[1] != null && srv[1].equals(cookieVal)) {
                return srv[0];
            }
        }
        return null;
    }

    // Simulate fix: O(1) hash map (models eb-tree O(log S))
    static String cookieLookup_tree(Map<String, String> cookieIndex, String cookieVal) {
        return cookieIndex.get(cookieVal);          // O(1) / O(log S) with eb-tree
    }

    static void testHaproxy0001() throws Exception {
        int S = 1000;   // backend servers
        List<String[]> servers = new ArrayList<>();
        Map<String, String> cookieIndex = new HashMap<>();

        for (int i = 0; i < S; i++) {
            String name = "backend" + i;
            String cookie = "srv" + String.format("%04d", i);
            servers.add(new String[]{name, cookie});
            cookieIndex.put(cookie, name);
        }

        // Request targets last server (worst case for linear scan)
        String target = "srv" + String.format("%04d", S - 1);

        // correctness
        String r1 = cookieLookup_list(servers, target);
        String r2 = cookieLookup_tree(cookieIndex, target);
        assert r1 != null && r1.equals(r2) : "list and tree must agree: " + r1 + " vs " + r2;
        assert cookieLookup_list(servers, "srvXXXX") == null;
        assert cookieLookup_tree(cookieIndex, "srvXXXX") == null;

        // performance: simulate R HTTP requests
        int R = 50_000;
        long t0 = System.nanoTime();
        for (int r = 0; r < R; r++) cookieLookup_list(servers, target);
        long tList = System.nanoTime() - t0;

        t0 = System.nanoTime();
        for (int r = 0; r < R; r++) cookieLookup_tree(cookieIndex, target);
        long tTree = System.nanoTime() - t0;

        double ratio = (double) tList / tTree;
        System.out.printf("haproxy-0001: list=%.3fs tree=%.3fs ratio=%.1f×%n",
                tList / 1e9, tTree / 1e9, ratio);
        assert ratio > 20 : "Expected >20× speedup, got " + ratio;
        System.out.println("PASS haproxy-0001");
    }

    public static void main(String[] args) throws Exception {
        testHaproxy0001();
        System.out.println("ALL PASS");
    }
}