import java.util.*;

/**
 * CWE-407 unit tests for VS Code defects.
 *
 * vscode-0001: extensionGalleryService getExtensions uuid dedup O(N×M)
 * vscode-0002: abstractExtensionManagementService getAllDepsAndPacks O(D²)
 * vscode-0003: userDataSync merge compare() O(N×M) array includes (8 sites)
 * vscode-0004: configurationModels override identifiers O(N×M)
 */
public class VscodeTest {

    // ---------------------------------------------------------------
    // vscode-0001: gallery uuid includes O(N×M)
    // ---------------------------------------------------------------

    /** BEFORE: uuids array with Array.includes() — O(N×M) */
    static int galleryUuidBefore(List<String> extensionUuids, List<String> resultUuids) {
        int ops = 0;
        // const uuids = result.map(r => r.identifier.uuid);  // array
        for (String uuid : extensionUuids) {
            // uuids.includes(e.uuid)
            for (String r : resultUuids) {
                ops++;
                if (r.equals(uuid)) break;
            }
        }
        return ops;
    }

    /** AFTER: uuids Set with Set.has() — O(N+M) */
    static int galleryUuidAfter(List<String> extensionUuids, List<String> resultUuids) {
        int ops = 0;
        Set<String> uuidSet = new HashSet<>(resultUuids);
        ops += resultUuids.size(); // set construction
        for (String uuid : extensionUuids) {
            ops++; // set lookup O(1)
            uuidSet.contains(uuid);
        }
        return ops;
    }

    // ---------------------------------------------------------------
    // vscode-0002: getAllDepsAndPacks includes O(D²)
    // ---------------------------------------------------------------

    /** BEFORE: allDepsOrPacks.includes() in recursive traversal — O(D²) */
    static int depsScanBefore(List<String> depChain) {
        int ops = 0;
        List<String> allDeps = new ArrayList<>();
        for (String id : depChain) {
            // allDepsOrPacks.includes(id.toLowerCase())
            boolean found = false;
            for (String existing : allDeps) {
                ops++;
                if (existing.equals(id)) { found = true; break; }
            }
            if (!found) allDeps.add(id);
        }
        return ops;
    }

    /** AFTER: Set for seen-check — O(D) */
    static int depsScanAfter(List<String> depChain) {
        int ops = 0;
        Set<String> seen = new HashSet<>();
        List<String> allDeps = new ArrayList<>();
        for (String id : depChain) {
            ops++; // set lookup
            if (!seen.contains(id)) {
                seen.add(id);
                allDeps.add(id);
            }
        }
        return ops;
    }

    // ---------------------------------------------------------------
    // vscode-0003: sync merge compare() — filter+includes O(N×M)
    // ---------------------------------------------------------------

    /** BEFORE: fromKeys.filter(key => !toKeys.includes(key)) — O(N×M) */
    static int mergeCompareBefore(List<String> fromKeys, List<String> toKeys) {
        int ops = 0;
        // added = toKeys.filter(key => !fromKeys.includes(key))
        for (String key : toKeys) {
            for (String fk : fromKeys) {
                ops++;
                if (fk.equals(key)) break;
            }
        }
        // removed = fromKeys.filter(key => !toKeys.includes(key))
        for (String key : fromKeys) {
            for (String tk : toKeys) {
                ops++;
                if (tk.equals(key)) break;
            }
        }
        return ops;
    }

    /** AFTER: Set lookup — O(N+M) */
    static int mergeCompareAfter(List<String> fromKeys, List<String> toKeys) {
        int ops = 0;
        Set<String> fromSet = new HashSet<>(fromKeys);
        ops += fromKeys.size();
        Set<String> toSet = new HashSet<>(toKeys);
        ops += toKeys.size();
        for (String key : toKeys) { ops++; fromSet.contains(key); }
        for (String key : fromKeys) { ops++; toSet.contains(key); }
        return ops;
    }

    // ---------------------------------------------------------------
    // vscode-0004: config override identifiers — filter+includes O(N×M)
    // ---------------------------------------------------------------

    /** BEFORE: overrideIdentifiers.filter + includes — O(N²) */
    static int configOverrideBefore(List<String> fromIds, List<String> toIds) {
        int ops = 0;
        // addedOverrideIdentifiers = toIds.filter(key => !fromIds.includes(key))
        for (String key : toIds) {
            for (String fk : fromIds) { ops++; if (fk.equals(key)) break; }
        }
        // removedOverrideIdentifiers = fromIds.filter(key => !toIds.includes(key))
        for (String key : fromIds) {
            for (String tk : toIds) { ops++; if (tk.equals(key)) break; }
        }
        // inner loop: toOverrideIdentifiers.includes(identifier)
        for (String id : fromIds) {
            for (String tk : toIds) { ops++; if (tk.equals(id)) break; }
        }
        return ops;
    }

    /** AFTER: Set lookups — O(N+M) */
    static int configOverrideAfter(List<String> fromIds, List<String> toIds) {
        int ops = 0;
        Set<String> fromSet = new HashSet<>(fromIds);
        ops += fromIds.size();
        Set<String> toSet = new HashSet<>(toIds);
        ops += toIds.size();
        for (String key : toIds) { ops++; fromSet.contains(key); }
        for (String key : fromIds) { ops++; toSet.contains(key); }
        for (String id : fromIds) { ops++; toSet.contains(id); }
        return ops;
    }

    // ---------------------------------------------------------------
    // Main: run all tests
    // ---------------------------------------------------------------
    public static void main(String[] args) {
        int pass = 0, fail = 0;

        // --- vscode-0001: gallery uuid ---
        {
            int N = 200;
            List<String> extUuids = new ArrayList<>();
            List<String> resultUuids = new ArrayList<>();
            for (int i = 0; i < N; i++) {
                extUuids.add("ext-" + i);
                resultUuids.add("res-" + i); // disjoint = worst case
            }
            int before = galleryUuidBefore(extUuids, resultUuids);
            int after = galleryUuidAfter(extUuids, resultUuids);
            double ratio = (double) before / after;
            boolean ok = ratio > 10;
            System.out.printf("vscode-0001 gallery-uuid        N=%d before=%d after=%d ratio=%.1fx %s%n",
                    N, before, after, ratio, ok ? "PASS" : "FAIL");
            if (ok) pass++; else fail++;
        }

        // --- vscode-0002: deps scan ---
        {
            int D = 100;
            List<String> deps = new ArrayList<>();
            for (int i = 0; i < D; i++) deps.add("dep-" + i);
            int before = depsScanBefore(deps);
            int after = depsScanAfter(deps);
            double ratio = (double) before / after;
            boolean ok = ratio > 10;
            System.out.printf("vscode-0002 deps-scan           D=%d before=%d after=%d ratio=%.1fx %s%n",
                    D, before, after, ratio, ok ? "PASS" : "FAIL");
            if (ok) pass++; else fail++;
        }

        // --- vscode-0003: sync merge compare ---
        {
            int N = 500;
            List<String> fromKeys = new ArrayList<>();
            List<String> toKeys = new ArrayList<>();
            for (int i = 0; i < N; i++) {
                fromKeys.add("setting-" + i);
                toKeys.add("setting-" + (i + N)); // disjoint = worst case
            }
            int before = mergeCompareBefore(fromKeys, toKeys);
            int after = mergeCompareAfter(fromKeys, toKeys);
            double ratio = (double) before / after;
            boolean ok = ratio > 50;
            System.out.printf("vscode-0003 sync-merge-compare  N=%d before=%d after=%d ratio=%.1fx %s%n",
                    N, before, after, ratio, ok ? "PASS" : "FAIL");
            if (ok) pass++; else fail++;
        }

        // --- vscode-0004: config override identifiers ---
        {
            int N = 30;
            List<String> fromIds = new ArrayList<>();
            List<String> toIds = new ArrayList<>();
            for (int i = 0; i < N; i++) {
                fromIds.add("[lang-" + i + "]");
                toIds.add("[lang-" + (i + N) + "]"); // disjoint
            }
            int before = configOverrideBefore(fromIds, toIds);
            int after = configOverrideAfter(fromIds, toIds);
            double ratio = (double) before / after;
            boolean ok = ratio > 5;
            System.out.printf("vscode-0004 config-overrides     N=%d before=%d after=%d ratio=%.1fx %s%n",
                    N, before, after, ratio, ok ? "PASS" : "FAIL");
            if (ok) pass++; else fail++;
        }

        System.out.printf("%n%d/%d PASS%n", pass, pass + fail);
        if (fail > 0) System.exit(1);
    }
}