/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

/* @test

 * @summary unit tests for java.lang.invoke.MethodHandle.invoke

 * @compile InvokeGenericTest.java

 * @run junit/othervm test.java.lang.invoke.InvokeGenericTest

 */

package test.java.lang.invoke;

import java.lang.invoke.*;

import static java.lang.invoke.MethodHandles.*;

import static java.lang.invoke.MethodType.*;

import java.lang.reflect.*;

import java.util.*;

import org.junit.*;

import static org.junit.Assert.*;

import static org.junit.Assume.*;

/**

 *

 * @author jrose

 */

@SuppressWarnings("cast")  // various casts help emphasize arguments to invokeExact

public class InvokeGenericTest {

    // How much output?

    static int verbosity = 0;

    static {

        String vstr = System.getProperty("test.java.lang.invoke.InvokeGenericTest.verbosity");

        if (vstr != null)  verbosity = Integer.parseInt(vstr);

    }

//    public static void main(String... av) throws Throwable {

//        new InvokeGenericTest().testFirst();

//    }

    @Test

    public void testFirst() throws Throwable {

        verbosity += 9; try {

            // left blank for debugging

        } finally { printCounts(); verbosity -= 9; }

    }

    public InvokeGenericTest() {

    }

    @Before

    public void checkImplementedPlatform() {

        boolean platformOK = false;

        Properties properties = System.getProperties();

        String vers = properties.getProperty("java.vm.version");

        String name = properties.getProperty("java.vm.name");

        String arch = properties.getProperty("os.arch");

        if ((arch.equals("amd64") || arch.equals("i386") || arch.equals("x86") ||

            (name.contains("Client") || name.contains("Server"))

            ) {

            platformOK = true;

        } else {

            System.err.println("Skipping tests for unsupported platform: "+Arrays.asList(vers, name, arch));

        }

        assumeTrue(platformOK);

    }

    String testName;

    static int allPosTests, allNegTests;

    int posTests, negTests;

    @After

    public void printCounts() {

        if (verbosity >= 2 && (posTests | negTests) != 0) {

            System.out.println();

            if (posTests != 0)  System.out.println("=== "+testName+": "+posTests+" positive test cases run");

            if (negTests != 0)  System.out.println("=== "+testName+": "+negTests+" negative test cases run");

            allPosTests += posTests;

            allNegTests += negTests;

            posTests = negTests = 0;

        }

    }

    void countTest(boolean positive) {

        if (positive) ++posTests;

        else          ++negTests;

    }

    void countTest() { countTest(true); }

    void startTest(String name) {

        if (testName != null)  printCounts();

        if (verbosity >= 1)

            System.out.println("["+name+"]");

        posTests = negTests = 0;

        testName = name;

    }

    @BeforeClass

    public static void setUpClass() throws Exception {

        calledLog.clear();

        calledLog.add(null);

        nextArgVal = INITIAL_ARG_VAL;

    }

    @AfterClass

    public static void tearDownClass() throws Exception {

        int posTests = allPosTests, negTests = allNegTests;

        if (verbosity >= 2 && (posTests | negTests) != 0) {

            System.out.println();

            if (posTests != 0)  System.out.println("=== "+posTests+" total positive test cases");

            if (negTests != 0)  System.out.println("=== "+negTests+" total negative test cases");

        }

    }

    static List<Object> calledLog = new ArrayList<>();

    static Object logEntry(String name, Object... args) {

        return Arrays.asList(name, Arrays.asList(args));

    }

    static Object called(String name, Object... args) {

        Object entry = logEntry(name, args);

        calledLog.add(entry);

        return entry;

    }

    static void assertCalled(String name, Object... args) {

        Object expected = logEntry(name, args);

        Object actual   = calledLog.get(calledLog.size() - 1);

        if (expected.equals(actual) && verbosity < 9)  return;

        System.out.println("assertCalled "+name+":");

        System.out.println("expected:   "+expected);

        System.out.println("actual:     "+actual);

        System.out.println("ex. types:  "+getClasses(expected));

        System.out.println("act. types: "+getClasses(actual));

        assertEquals("previous method call", expected, actual);

    }

    static void printCalled(MethodHandle target, String name, Object... args) {

        if (verbosity >= 3)

            System.out.println("calling MH="+target+" to "+name+Arrays.toString(args));

    }

    static Object castToWrapper(Object value, Class<?> dst) {

        Object wrap = null;

        if (value instanceof Number)

            wrap = castToWrapperOrNull(((Number)value).longValue(), dst);

        if (value instanceof Character)

            wrap = castToWrapperOrNull((char)(Character)value, dst);

        if (wrap != null)  return wrap;

        return dst.cast(value);

    }

    static Object castToWrapperOrNull(long value, Class<?> dst) {

        if (dst == int.class || dst == Integer.class)

            return (int)(value);

        if (dst == long.class || dst == Long.class)

            return (long)(value);

        if (dst == char.class || dst == Character.class)

            return (char)(value);

        if (dst == short.class || dst == Short.class)

            return (short)(value);

        if (dst == float.class || dst == Float.class)

            return (float)(value);

        if (dst == double.class || dst == Double.class)

            return (double)(value);

        if (dst == byte.class || dst == Byte.class)

            return (byte)(value);

        if (dst == boolean.class || dst == boolean.class)

            return ((value % 29) & 1) == 0;

        return null;

    }

    static final int ONE_MILLION = (1000*1000),  // first int value

                     TEN_BILLION = (10*1000*1000*1000),  // scale factor to reach upper 32 bits

                     INITIAL_ARG_VAL = ONE_MILLION << 1;  // <<1 makes space for sign bit;

    static long nextArgVal;

    static long nextArg(boolean moreBits) {

        long val = nextArgVal++;

        long sign = -(val & 1); // alternate signs

        val >>= 1;

        if (moreBits)

            // Guarantee some bits in the high word.

            // In any case keep the decimal representation simple-looking,

            // with lots of zeroes, so as not to make the printed decimal

            // strings unnecessarily noisy.

            val += (val % ONE_MILLION) * TEN_BILLION;

        return val ^ sign;

    }

    static int nextArg() {

        // Produce a 32-bit result something like ONE_MILLION+(smallint).

        // Example: 1_000_042.

        return (int) nextArg(false);

    }

    static long nextArg(Class<?> kind) {

        if (kind == long.class   || kind == Long.class ||

            kind == double.class || kind == Double.class)

            // produce a 64-bit result something like

            // ((TEN_BILLION+1) * (ONE_MILLION+(smallint)))

            // Example: 10_000_420_001_000_042.

            return nextArg(true);

        return (long) nextArg();

    }

    static Object randomArg(Class<?> param) {

        Object wrap = castToWrapperOrNull(nextArg(param), param);

        if (wrap != null) {

            return wrap;

        }

//        import sun.invoke.util.Wrapper;

//        Wrapper wrap = Wrapper.forBasicType(dst);

//        if (wrap == Wrapper.OBJECT && Wrapper.isWrapperType(dst))

//            wrap = Wrapper.forWrapperType(dst);

//        if (wrap != Wrapper.OBJECT)

//            return wrap.wrap(nextArg++);

        if (param.isInterface()) {

            for (Class<?> c : param.getClasses()) {

                if (param.isAssignableFrom(c) && !c.isInterface())

                    { param = c; break; }

            }

        }

        if (param.isInterface() || param.isAssignableFrom(String.class))

            return "#"+nextArg();

        else

            try {

                return param.newInstance();

            } catch (InstantiationException | IllegalAccessException ex) {

            }

        return null;  // random class not Object, String, Integer, etc.

    }

    static Object[] randomArgs(Class<?>... params) {

        Object[] args = new Object[params.length];

        for (int i = 0; i < args.length; i++)

            args[i] = randomArg(params[i]);

        return args;

    }

    static Object[] randomArgs(int nargs, Class<?> param) {

        Object[] args = new Object[nargs];

        for (int i = 0; i < args.length; i++)

            args[i] = randomArg(param);

        return args;

    }

    static final Object ANON_OBJ = new Object();

    static Object zeroArg(Class<?> param) {

        Object x = castToWrapperOrNull(0L, param);

        if (x != null)  return x;

        if (param.isInterface() || param.isAssignableFrom(String.class))  return "\"\"";

        if (param == Object.class)  return ANON_OBJ;

        if (param.getComponentType() != null)  return Array.newInstance(param.getComponentType(), 0);

        return null;

    }

    static Object[] zeroArgs(Class<?>... params) {

        Object[] args = new Object[params.length];

        for (int i = 0; i < args.length; i++)

            args[i] = zeroArg(params[i]);

        return args;

    }

    static Object[] zeroArgs(List<Class<?>> params) {

        return zeroArgs(params.toArray(new Class<?>[0]));

    }

    @SafeVarargs @SuppressWarnings("varargs")

    static <T, E extends T> T[] array(Class<T[]> atype, E... a) {

        return Arrays.copyOf(a, a.length, atype);

    }

    @SafeVarargs @SuppressWarnings("varargs")

    static <T> T[] cat(T[] a, T... b) {

        int alen = a.length, blen = b.length;

        if (blen == 0)  return a;

        T[] c = Arrays.copyOf(a, alen + blen);

        System.arraycopy(b, 0, c, alen, blen);

        return c;

    }

    static Integer[] boxAll(int... vx) {

        Integer[] res = new Integer[vx.length];

        for (int i = 0; i < res.length; i++) {

            res[i] = vx[i];

        }

        return res;

    }

    static Object getClasses(Object x) {

        if (x == null)  return x;

        if (x instanceof String)  return x;  // keep the name

        if (x instanceof List) {

            // recursively report classes of the list elements

            Object[] xa = ((List)x).toArray();

            for (int i = 0; i < xa.length; i++)

                xa[i] = getClasses(xa[i]);

            return Arrays.asList(xa);

        }

        return x.getClass().getSimpleName();

    }

    static MethodHandle changeArgTypes(MethodHandle target, Class<?> argType) {

        return changeArgTypes(target, 0, 999, argType);

    }

    static MethodHandle changeArgTypes(MethodHandle target,

            int beg, int end, Class<?> argType) {

        MethodType targetType = target.type();

        end = Math.min(end, targetType.parameterCount());

        ArrayList<Class<?>> argTypes = new ArrayList<>(targetType.parameterList());

        Collections.fill(argTypes.subList(beg, end), argType);

        MethodType ttype2 = MethodType.methodType(targetType.returnType(), argTypes);

        return target.asType(ttype2);

    }

    // This lookup is good for all members in and under InvokeGenericTest.

    static final Lookup LOOKUP = MethodHandles.lookup();

    Map<List<Class<?>>, MethodHandle> CALLABLES = new HashMap<>();

    MethodHandle callable(List<Class<?>> params) {

        MethodHandle mh = CALLABLES.get(params);

        if (mh == null) {

            mh = collector_MH.asType(methodType(Object.class, params));

            CALLABLES.put(params, mh);

        }

        return mh;

    }

    MethodHandle callable(Class<?>... params) {

        return callable(Arrays.asList(params));

    }

    private static Object collector(Object... args) {

        return Arrays.asList(args);

    }

    private static final MethodHandle collector_MH;

    static {

        try {

            collector_MH

                = LOOKUP.findStatic(LOOKUP.lookupClass(),

                                    "collector",

                                    methodType(Object.class, Object[].class));

        } catch (ReflectiveOperationException ex) {

            throw new RuntimeException(ex);

        }

    }

    @Test

    public void testSimple() throws Throwable {

        startTest("testSimple");

        countTest();

        String[] args = { "one", "two" };

        MethodHandle mh = callable(Object.class, String.class);

        Object res; List<?> resl;

        res = resl = (List<?>) mh.invoke((String)args[0], (Object)args[1]);

        //System.out.println(res);

        assertEquals(Arrays.asList(args), res);

    }

    @Test

    public void testSimplePrims() throws Throwable {

        startTest("testSimplePrims");

        countTest();

        int[] args = { 1, 2 };

        MethodHandle mh = callable(Object.class, Object.class);

        Object res; List<?> resl;

        res = resl = (List<?>) mh.invoke(args[0], args[1]);

        //System.out.println(res);

        assertEquals(Arrays.toString(args), res.toString());

    }

    @Test

    public void testAlternateName() throws Throwable {

        startTest("testAlternateName");

        countTest();

        String[] args = { "one", "two" };

        MethodHandle mh = callable(Object.class, String.class);

        Object res; List<?> resl;

        res = resl = (List<?>) mh.invoke((String)args[0], (Object)args[1]);

        //System.out.println(res);

        assertEquals(Arrays.asList(args), res);

    }

    @Test

    public void testWrongArgumentCount() throws Throwable {

        startTest("testWrongArgumentCount");

        for (int i = 0; i <= 10; i++) {

            testWrongArgumentCount(Collections.<Class<?>>nCopies(i, Integer.class));

            if (i <= 4) {

                testWrongArgumentCount(Collections.<Class<?>>nCopies(i, int.class));

                testWrongArgumentCount(Collections.<Class<?>>nCopies(i, long.class));

            }

        }

    }

    public void testWrongArgumentCount(List<Class<?>> params) throws Throwable {

        int max = params.size();

        for (int i = 0; i < max; i++) {

            List<Class<?>> params2 = params.subList(0, i);

            for (int k = 0; k <= 2; k++) {

                if (k == 1)  params  = methodType(Object.class,  params).generic().parameterList();

                if (k == 2)  params2 = methodType(Object.class, params2).generic().parameterList();

                testWrongArgumentCount(params, params2);

                testWrongArgumentCount(params2, params);

            }

        }

    }

    public void testWrongArgumentCount(List<Class<?>> expect, List<Class<?>> observe) throws Throwable {

        countTest(false);

        if (expect.equals(observe))

            assert(false);

        MethodHandle target = callable(expect);

        Object[] args = zeroArgs(observe);

        Object junk;

        try {

            switch (args.length) {

            case 0:

                junk = target.invoke(); break;

            case 1:

                junk = target.invoke(args[0]); break;

            case 2:

                junk = target.invoke(args[0], args[1]); break;

            case 3:

                junk = target.invoke(args[0], args[1], args[2]); break;

            case 4:

                junk = target.invoke(args[0], args[1], args[2], args[3]); break;

            default:

                junk = target.invokeWithArguments(args); break;

            }

        } catch (WrongMethodTypeException ex) {

            return;

        } catch (Exception ex) {

            throw new RuntimeException("wrong exception calling "+target+" on "+Arrays.asList(args), ex);

        }

        throw new RuntimeException("bad success calling "+target+" on "+Arrays.asList(args));

    }

    /** Make a list of all combinations of the given types, with the given arities.

     *  A void return type is possible iff the first type is void.class.

     */

    static List<MethodType> allMethodTypes(int minargc, int maxargc, Class<?>... types) {

        ArrayList<MethodType> result = new ArrayList<>();

        if (types.length > 0) {

            ArrayList<MethodType> argcTypes = new ArrayList<>();

            // build arity-zero types first

            for (Class<?> rtype : types) {

                argcTypes.add(MethodType.methodType(rtype));

            }

            if (types[0] == void.class)

                // void is not an argument type

                types = Arrays.copyOfRange(types, 1, types.length);

            for (int argc = 0; argc <= maxargc; argc++) {

                if (argc >= minargc)

                    result.addAll(argcTypes);

                if (argc >= maxargc)

                    break;

                ArrayList<MethodType> prevTypes = argcTypes;

                argcTypes = new ArrayList<>();

                for (MethodType prevType : prevTypes) {

                    for (Class<?> ptype : types) {

                        argcTypes.add(prevType.insertParameterTypes(argc, ptype));

                    }

                }

            }

        }

        return Collections.unmodifiableList(result);

    }

    static List<MethodType> allMethodTypes(int argc, Class<?>... types) {

        return allMethodTypes(argc, argc, types);

    }

    MethodHandle toString_MH;

    @Test

    public void testReferenceConversions() throws Throwable {

        startTest("testReferenceConversions");

        toString_MH = LOOKUP.

            findVirtual(Object.class, "toString", MethodType.methodType(String.class));

        Object[] args = { "one", "two" };

        for (MethodType type : allMethodTypes(2, Object.class, String.class, CharSequence.class)) {

            testReferenceConversions(type, args);

        }

    }

    public void testReferenceConversions(MethodType type, Object... args) throws Throwable {

        countTest();

        int nargs = args.length;

        List<Object> argList = Arrays.asList(args);

        String expectString = argList.toString();

        if (verbosity > 3)  System.out.println("target type: "+type+expectString);

        MethodHandle mh = callable(type.parameterList());

        mh = MethodHandles.filterReturnValue(mh, toString_MH);

        mh = mh.asType(type);

        Object res = null;

        if (nargs == 2) {

            res = mh.invoke((Object)args[0], (Object)args[1]);

            assertEquals(expectString, res);

            res = mh.invoke((String)args[0], (Object)args[1]);

            assertEquals(expectString, res);

            res = mh.invoke((Object)args[0], (String)args[1]);

            assertEquals(expectString, res);

            res = mh.invoke((String)args[0], (String)args[1]);

            assertEquals(expectString, res);

            res = mh.invoke((String)args[0], (CharSequence)args[1]);

            assertEquals(expectString, res);

            res = mh.invoke((CharSequence)args[0], (Object)args[1]);

            assertEquals(expectString, res);

            res = (String) mh.invoke((Object)args[0], (Object)args[1]);

            assertEquals(expectString, res);

            res = (String) mh.invoke((String)args[0], (Object)args[1]);

            assertEquals(expectString, res);

            res = (CharSequence) mh.invoke((String)args[0], (Object)args[1]);

            assertEquals(expectString, res);

        } else {

            assert(false);  // write this code