#include "prx/libc/include/Api.hpp"
#include <algorithm>
#include <array>
#include <cstddef>
#include <cstdint>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <string>
#include <vector>

static void Require(bool condition) {
    if (!condition) {
        std::fputs("GuestCharSearchBoundary check failed\n", stderr);
        std::abort();
    }
}

#ifdef _WIN32
#include <windows.h>
#else
#include <sys/mman.h>
#include <unistd.h>
#endif

class Buffer {
    unsigned char* allocation;
    std::size_t page;
public:
    Buffer() {
#ifdef _WIN32
        SYSTEM_INFO info{};
        GetSystemInfo(&info);
        page = info.dwPageSize;
        allocation = static_cast<unsigned char*>(VirtualAlloc(nullptr, page * 3, MEM_RESERVE | MEM_COMMIT, PAGE_NOACCESS));
        Require(allocation != nullptr);
        DWORD previous;
        Require(VirtualProtect(allocation + page, page, PAGE_READWRITE, &previous) != 0);
#else
        const long size = sysconf(_SC_PAGESIZE);
        Require(size > 0);
        page = static_cast<std::size_t>(size);
        allocation = static_cast<unsigned char*>(mmap(nullptr, page * 3, PROT_NONE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0));
        Require(allocation != MAP_FAILED);
        Require(mprotect(allocation + page, page, PROT_READ | PROT_WRITE) == 0);
#endif
        std::memset(allocation + page, 0xa5, page);
    }
    ~Buffer() {
#ifdef _WIN32
        Require(VirtualFree(allocation, 0, MEM_RELEASE) != 0);
#else
        Require(munmap(allocation, page * 3) == 0);
#endif
    }
    Buffer(const Buffer&) = delete;
    Buffer& operator=(const Buffer&) = delete;
    template<class T = unsigned char>
    T* At(std::size_t count) {
        Require(count <= (page - 32) / sizeof(T));
        return reinterpret_cast<T*>(allocation + page * 2 - (std::max)(count, std::size_t{1}) * sizeof(T));
    }
};

template<class T>
static void Prefix(const T* data) {
    for (int index = 1; index <= 8; ++index) Require(data[-index] == static_cast<T>(sizeof(T) == 1 ? 0xa5 : 0xa5a5));
}

int main() {
    Buffer input;
    for (std::size_t count = 0; count <= 128; ++count) {
        auto* source = input.At<char>(count + 1);
        for (std::size_t index = 0; index < count; ++index) source[index] = static_cast<char>(std::array<unsigned char, 5>{1, 0x7f, 0x80, 0xe9, 0xff}[(index + count) % 5]);
        source[count] = 0;
        const std::string saved(source, count + 1);
        for (int value : {-256, -23, -1, 0, 1, 127, 128, 233, 255, 256, 489, 511, (-2147483647 - 1), 2147483647}) {
            const char* first = nullptr;
            const char* last = nullptr;
            for (std::size_t index = 0; index <= count; ++index) {
                if (static_cast<unsigned char>(source[index]) == static_cast<unsigned char>(value)) {
                    if (first == nullptr) first = source + index;
                    last = source + index;
                }
            }
            Require(strchr_nid_postfix(source, value) == first);
            Require(strrchr_nid_postfix(source, value) == last);
            Require(std::equal(saved.begin(), saved.end(), source));
        }
    }
}