// SPDX-FileCopyrightText: Copyright (c) 2022 merryhime <https://mary.rs>
// SPDX-License-Identifier: MIT

#include <cstdint>
#include <cstdio>
#include <limits>

#include <catch2/catch_test_macros.hpp>

#include "oaknut/code_block.hpp"
#include "oaknut/dual_code_block.hpp"
#include "oaknut/oaknut.hpp"
#include "rand_int.hpp"

using namespace oaknut;
using namespace oaknut::util;

TEST_CASE("Basic Test")
{
    CodeBlock mem{4096};
    CodeGenerator code{mem.ptr(), mem.ptr()};

    mem.unprotect();

    code.MOV(W0, 42);
    code.RET();

    mem.protect();
    mem.invalidate_all();

    int result = ((int (*)())mem.ptr())();
    REQUIRE(result == 42);
}

TEST_CASE("Basic Test (Dual)")
{
    DualCodeBlock mem{4096};
    CodeGenerator code{mem.wptr(), mem.xptr()};

    code.MOV(W0, 42);
    code.RET();

    mem.invalidate_all();

    int result = ((int (*)())mem.xptr())();
    REQUIRE(result == 42);
}

TEST_CASE("Fibonacci")
{
    CodeBlock mem{4096};
    CodeGenerator code{mem.ptr(), mem.ptr()};

    mem.unprotect();

    auto fib = code.xptr<int (*)(int)>();
    Label start, end, zero, recurse;

    code.l(start);
    code.STP(X29, X30, SP, PRE_INDEXED, -32);
    code.STP(X20, X19, SP, 16);
    code.MOV(X29, SP);
    code.MOV(W19, W0);
    code.SUBS(W0, W0, 1);
    code.B(LT, zero);
    code.B(NE, recurse);
    code.MOV(W0, 1);
    code.B(end);

    code.l(zero);
    code.MOV(W0, WZR);
    code.B(end);

    code.l(recurse);
    code.BL(start);
    code.MOV(W20, W0);
    code.SUB(W0, W19, 2);
    code.BL(start);
    code.ADD(W0, W0, W20);

    code.l(end);
    code.LDP(X20, X19, SP, 16);
    code.LDP(X29, X30, SP, POST_INDEXED, 32);
    code.RET();

    mem.protect();
    mem.invalidate_all();

    REQUIRE(fib(0) == 0);
    REQUIRE(fib(1) == 1);
    REQUIRE(fib(5) == 5);
    REQUIRE(fib(9) == 34);
}

TEST_CASE("Fibonacci (Dual)")
{
    DualCodeBlock mem{4096};
    CodeGenerator code{mem.wptr(), mem.xptr()};

    auto fib = code.xptr<int (*)(int)>();
    Label start, end, zero, recurse;

    code.l(start);
    code.STP(X29, X30, SP, PRE_INDEXED, -32);
    code.STP(X20, X19, SP, 16);
    code.MOV(X29, SP);
    code.MOV(W19, W0);
    code.SUBS(W0, W0, 1);
    code.B(LT, zero);
    code.B(NE, recurse);
    code.MOV(W0, 1);
    code.B(end);

    code.l(zero);
    code.MOV(W0, WZR);
    code.B(end);

    code.l(recurse);
    code.BL(start);
    code.MOV(W20, W0);
    code.SUB(W0, W19, 2);
    code.BL(start);
    code.ADD(W0, W0, W20);

    code.l(end);
    code.LDP(X20, X19, SP, 16);
    code.LDP(X29, X30, SP, POST_INDEXED, 32);
    code.RET();

    mem.invalidate_all();

    REQUIRE(fib(0) == 0);
    REQUIRE(fib(1) == 1);
    REQUIRE(fib(5) == 5);
    REQUIRE(fib(9) == 34);
}

TEST_CASE("Immediate generation (32-bit)", "[slow]")
{
    CodeBlock mem{4096};

    for (int i = 0; i < 0x100000; i++) {
        const std::uint32_t value = RandInt<std::uint32_t>(0, 0xffffffff);

        CodeGenerator code{mem.ptr(), mem.ptr()};

        auto f = code.xptr<std::uint64_t (*)()>();
        mem.unprotect();
        code.MOV(W0, value);
        code.RET();
        mem.protect();
        mem.invalidate_all();

        REQUIRE(f() == value);
    }
}

TEST_CASE("Immediate generation (64-bit)", "[slow]")
{
    CodeBlock mem{4096};

    for (int i = 0; i < 0x100000; i++) {
        const std::uint64_t value = RandInt<std::uint64_t>(0, 0xffffffff'ffffffff);

        CodeGenerator code{mem.ptr(), mem.ptr()};

        auto f = code.xptr<std::uint64_t (*)()>();
        mem.unprotect();
        code.MOV(X0, value);
        code.RET();
        mem.protect();
        mem.invalidate_all();

        REQUIRE(f() == value);
    }
}

TEST_CASE("ADR", "[slow]")
{
    CodeBlock mem{4096};

    for (std::int64_t i = -1048576; i < 1048576; i++) {
        const std::intptr_t value = reinterpret_cast<std::intptr_t>(mem.ptr()) + i;

        CodeGenerator code{mem.ptr(), mem.ptr()};

        auto f = code.xptr<std::intptr_t (*)()>();
        mem.unprotect();
        code.ADR(X0, reinterpret_cast<void*>(value));
        code.RET();
        mem.protect();
        mem.invalidate_all();

        INFO(i);
        REQUIRE(f() == value);
    }
}

TEST_CASE("PageOffset (rollover)")
{
    REQUIRE(PageOffset<21, 12>::encode(0x0000000088e74000, 0xffffffffd167dece) == 0xd2202);
}

TEST_CASE("PageOffset (page boundary)")
{
    REQUIRE(PageOffset<21, 12>::encode(0x0001000000000002, 0x0001000000000001) == 0);
    REQUIRE(PageOffset<21, 12>::encode(0x0001000000000001, 0x0001000000000002) == 0);
    REQUIRE(PageOffset<21, 12>::encode(0x0001000000001000, 0x0001000000000fff) == 0x1fffff);
    REQUIRE(PageOffset<21, 12>::encode(0x0001000000000fff, 0x0001000000001000) == 0x080000);
}

TEST_CASE("ADRP", "[slow]")
{
    CodeBlock mem{4096};

    for (int i = 0; i < 0x200000; i++) {
        const std::int64_t diff = RandInt<std::int64_t>(-4294967296, 4294967295);
        const std::intptr_t value = reinterpret_cast<std::intptr_t>(mem.ptr()) + diff;
        const std::uint64_t expect = static_cast<std::uint64_t>(value) & ~static_cast<std::uint64_t>(0xfff);

        CodeGenerator code{mem.ptr(), mem.ptr()};

        auto f = code.xptr<std::uint64_t (*)()>();
        mem.unprotect();
        code.ADRP(X0, reinterpret_cast<void*>(value));
        code.RET();
        mem.protect();
        mem.invalidate_all();

        INFO(i);
        REQUIRE(f() == expect);
    }
}

TEST_CASE("ADRL (near)")
{
    CodeBlock mem{4096};
    std::uint32_t* const mem_ptr = mem.ptr() + 42;  // create small offset for testing

    for (int i = -0x4000; i < 0x4000; i++) {
        const std::int64_t diff = i;
        const std::intptr_t value = reinterpret_cast<std::intptr_t>(mem_ptr) + diff;

        CodeGenerator code{mem_ptr, mem_ptr};

        auto f = code.xptr<std::uint64_t (*)()>();
        mem.unprotect();
        code.ADRL(X0, reinterpret_cast<void*>(value));
        code.RET();
        mem.protect();
        mem.invalidate_all();

        INFO(i);
        REQUIRE(f() == static_cast<std::uint64_t>(value));
    }
}

TEST_CASE("ADRL (far)", "[slow]")
{
    CodeBlock mem{4096};
    std::uint32_t* const mem_ptr = mem.ptr() + 42;  // create small offset for testing

    for (int i = 0; i < 0x200000; i++) {
        const std::int64_t diff = RandInt<std::int64_t>(-4294967296 + 100, 4294967295 - 100);
        const std::intptr_t value = reinterpret_cast<std::intptr_t>(mem_ptr) + diff;

        CodeGenerator code{mem_ptr, mem_ptr};

        auto f = code.xptr<std::uint64_t (*)()>();
        mem.unprotect();
        code.ADRL(X0, reinterpret_cast<void*>(value));
        code.RET();
        mem.protect();
        mem.invalidate_all();

        INFO(i);
        REQUIRE(f() == static_cast<std::uint64_t>(value));
    }
}

TEST_CASE("MOVP2R (far)", "[slow]")
{
    CodeBlock mem{4096};
    std::uint32_t* const mem_ptr = mem.ptr() + 42;  // create small offset for testing

    for (int i = 0; i < 0x200000; i++) {
        const std::int64_t diff = RandInt<std::int64_t>(std::numeric_limits<std::int64_t>::min(),
                                                        std::numeric_limits<std::int64_t>::max());
        const std::intptr_t value = reinterpret_cast<std::intptr_t>(mem_ptr) + diff;

        CodeGenerator code{mem_ptr, mem_ptr};

        auto f = code.xptr<std::uint64_t (*)()>();
        mem.unprotect();
        code.MOVP2R(X0, reinterpret_cast<void*>(value));
        code.RET();
        mem.protect();
        mem.invalidate_all();

        REQUIRE(f() == static_cast<std::uint64_t>(value));
    }
}

TEST_CASE("MOVP2R (4GiB boundary)")
{
    CodeBlock mem{4096};
    std::uint32_t* const mem_ptr = mem.ptr() + 42;  // create small offset for testing

    for (std::int64_t i = 0xFFFF'F000; i < 0x1'0000'1000; i++) {
        const auto test = [&](std::int64_t diff) {
            const std::intptr_t value = reinterpret_cast<std::intptr_t>(mem_ptr) + diff;

            CodeGenerator code{mem_ptr, mem_ptr};

            auto f = code.xptr<std::uint64_t (*)()>();
            mem.unprotect();
            code.MOVP2R(X0, reinterpret_cast<void*>(value));
            code.RET();
            mem.protect();
            mem.invalidate_all();

            REQUIRE(f() == static_cast<std::uint64_t>(value));
        };
        test(i);
        test(-i);
    }
}