/*
 * Copyright 2014 Google Inc.
 *
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#include "SkRandom.h"
#include "SkRefCnt.h"
#include "SkTArray.h"
#include "Test.h"

// Tests the SkTArray<T> class template.

template <bool MEM_MOVE>
static void TestTSet_basic(skiatest::Reporter* reporter) {
    SkTArray<int, MEM_MOVE> a;

    // Starts empty.
    REPORTER_ASSERT(reporter, a.empty());
    REPORTER_ASSERT(reporter, a.count() == 0);

    // { }, add a default constructed element
    a.push_back() = 0;
    REPORTER_ASSERT(reporter, !a.empty());
    REPORTER_ASSERT(reporter, a.count() == 1);

    // { 0 }, removeShuffle the only element.
    a.removeShuffle(0);
    REPORTER_ASSERT(reporter, a.empty());
    REPORTER_ASSERT(reporter, a.count() == 0);

    // { }, add a default, add a 1, remove first
    a.push_back() = 0;
    REPORTER_ASSERT(reporter, a.push_back() = 1);
    a.removeShuffle(0);
    REPORTER_ASSERT(reporter, !a.empty());
    REPORTER_ASSERT(reporter, a.count() == 1);
    REPORTER_ASSERT(reporter, a[0] == 1);

    // { 1 }, replace with new array
    int b[5] = { 0, 1, 2, 3, 4 };
    a.reset(b, SK_ARRAY_COUNT(b));
    REPORTER_ASSERT(reporter, a.count() == SK_ARRAY_COUNT(b));
    REPORTER_ASSERT(reporter, a[2] == 2);
    REPORTER_ASSERT(reporter, a[4] == 4);

    // { 0, 1, 2, 3, 4 }, removeShuffle the last
    a.removeShuffle(4);
    REPORTER_ASSERT(reporter, a.count() == SK_ARRAY_COUNT(b) - 1);
    REPORTER_ASSERT(reporter, a[3] == 3);

    // { 0, 1, 2, 3 }, remove a middle, note shuffle
    a.removeShuffle(1);
    REPORTER_ASSERT(reporter, a.count() == SK_ARRAY_COUNT(b) - 2);
    REPORTER_ASSERT(reporter, a[0] == 0);
    REPORTER_ASSERT(reporter, a[1] == 3);
    REPORTER_ASSERT(reporter, a[2] == 2);

    // {0, 3, 2 }
}

template <typename T> static void test_swap(skiatest::Reporter* reporter,
                                            SkTArray<T>* (&arrays)[4],
                                            int (&sizes)[7])
{
    for (auto a : arrays) {
    for (auto b : arrays) {
        if (a == b) {
            continue;
        }

        for (auto sizeA : sizes) {
        for (auto sizeB : sizes) {
            a->reset();
            b->reset();

            int curr = 0;
            for (int i = 0; i < sizeA; i++) { a->push_back(curr++); }
            for (int i = 0; i < sizeB; i++) { b->push_back(curr++); }

            a->swap(*b);
            REPORTER_ASSERT(reporter, b->count() == sizeA);
            REPORTER_ASSERT(reporter, a->count() == sizeB);

            curr = 0;
            for (auto&& x : *b) { REPORTER_ASSERT(reporter, x == curr++); }
            for (auto&& x : *a) { REPORTER_ASSERT(reporter, x == curr++); }

            a->swap(*a);
            curr = sizeA;
            for (auto&& x : *a) { REPORTER_ASSERT(reporter, x == curr++); }
        }}
    }}
}

static void test_swap(skiatest::Reporter* reporter) {
    int sizes[] = {0, 1, 5, 10, 15, 20, 25};

    SkTArray<int> arr;
    SkSTArray< 5, int> arr5;
    SkSTArray<10, int> arr10;
    SkSTArray<20, int> arr20;
    SkTArray<int>* arrays[] = { &arr, &arr5, &arr10, &arr20 };
    test_swap(reporter, arrays, sizes);

    struct MoveOnlyInt {
        MoveOnlyInt(int i) : fInt(i) {}
        MoveOnlyInt(MoveOnlyInt&& that) : fInt(that.fInt) {}
        bool operator==(int i) { return fInt == i; }
        int fInt;
    };

    SkTArray<MoveOnlyInt> moi;
    SkSTArray< 5, MoveOnlyInt> moi5;
    SkSTArray<10, MoveOnlyInt> moi10;
    SkSTArray<20, MoveOnlyInt> moi20;
    SkTArray<MoveOnlyInt>* arraysMoi[] = { &moi, &moi5, &moi10, &moi20 };
    test_swap(reporter, arraysMoi, sizes);
}

template <typename T, bool MEM_MOVE> int SkTArray<T, MEM_MOVE>::allocCntForTest() const {
    return fAllocCount;
}

void test_unnecessary_alloc(skiatest::Reporter* reporter) {
    {
        SkTArray<int> a;
        REPORTER_ASSERT(reporter, a.allocCntForTest() == 0);
    }
    {
        SkSTArray<10, int> a;
        REPORTER_ASSERT(reporter, a.allocCntForTest() == 10);
    }
    {
        SkTArray<int> a(1);
        REPORTER_ASSERT(reporter, a.allocCntForTest() >= 1);
    }
    {
        SkTArray<int> a, b;
        b = a;
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
    {
        SkSTArray<10, int> a;
        SkTArray<int> b;
        b = a;
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
    {
        SkTArray<int> a;
        SkTArray<int> b(a);
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
    {
        SkSTArray<10, int> a;
        SkTArray<int> b(a);
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
    {
        SkTArray<int> a;
        SkTArray<int> b(std::move(a));
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
    {
        SkSTArray<10, int> a;
        SkTArray<int> b(std::move(a));
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
    {
        SkTArray<int> a;
        SkTArray<int> b;
        b = std::move(a);
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
    {
        SkSTArray<10, int> a;
        SkTArray<int> b;
        b = std::move(a);
        REPORTER_ASSERT(reporter, b.allocCntForTest() == 0);
    }
}

static void test_self_assignment(skiatest::Reporter* reporter) {
    SkTArray<int> a;
    a.push_back(1);
    REPORTER_ASSERT(reporter, !a.empty());
    REPORTER_ASSERT(reporter, a.count() == 1);
    REPORTER_ASSERT(reporter, a[0] == 1);

    a = static_cast<decltype(a)&>(a);
    REPORTER_ASSERT(reporter, !a.empty());
    REPORTER_ASSERT(reporter, a.count() == 1);
    REPORTER_ASSERT(reporter, a[0] == 1);
}

template <typename Array> static void test_array_reserve(skiatest::Reporter* reporter,
                                                         Array* array, int reserveCount) {
    SkRandom random;
    REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
    array->push_back();
    REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
    array->pop_back();
    REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
    while (array->count() < reserveCount) {
        // Two steps forward, one step back
        if (random.nextULessThan(3) < 2) {
            array->push_back();
        } else if (array->count() > 0) {
            array->pop_back();
        }
        REPORTER_ASSERT(reporter, array->allocCntForTest() >= reserveCount);
    }
}

template<typename Array> static void test_reserve(skiatest::Reporter* reporter) {
    // Test that our allocated space stays >= to the reserve count until the array is filled to
    // the reserve count
    for (int reserveCount : {1, 2, 10, 100}) {
        // Test setting reserve in constructor.
        Array array1(reserveCount);
        test_array_reserve(reporter, &array1, reserveCount);

        // Test setting reserve after constructor.
        Array array2;
        array2.reserve(reserveCount);
        test_array_reserve(reporter, &array2, reserveCount);

        // Test increasing reserve after constructor.
        Array array3(reserveCount/2);
        array3.reserve(reserveCount);
        test_array_reserve(reporter, &array3, reserveCount);

        // Test setting reserve on non-empty array.
        Array array4;
        array4.push_back_n(reserveCount);
        array4.reserve(reserveCount);
        array4.pop_back_n(reserveCount);
        test_array_reserve(reporter, &array4, 2 * reserveCount);
    }
}

DEF_TEST(TArray, reporter) {
    TestTSet_basic<true>(reporter);
    TestTSet_basic<false>(reporter);
    test_swap(reporter);

    test_unnecessary_alloc(reporter);

    test_self_assignment(reporter);

    test_reserve<SkTArray<int>>(reporter);
    test_reserve<SkSTArray<1, int>>(reporter);
    test_reserve<SkSTArray<2, int>>(reporter);
    test_reserve<SkSTArray<16, int>>(reporter);
}