#include "Core.h"
#include "Debug.h"
#include "Export.h"
#include "PluginManager.h"
#include "Hooks.h"

#include <iostream>
#include <map>
#include <string>
#include <vector>

#include <stdio.h>
#include <stdint.h>

#ifdef WIN32
#define NOMINMAX
#include <windows.h>
#define global_search_handle() GetModuleHandle(nullptr)
#define get_function_address(plugin, function) GetProcAddress((HMODULE)plugin, function)
#define clear_error()
#define load_library(fn) LoadLibraryW(fn.c_str())
#define close_library(handle) (!(FreeLibrary((HMODULE)handle)))
#else
#include <dlfcn.h>
#include <stdlib.h>
#include <string.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#define global_search_handle() (RTLD_DEFAULT)
#define get_function_address(plugin, function) dlsym((void*)plugin, function)
#define clear_error() dlerror()
#define load_library(fn) dlopen(fn.c_str(), RTLD_NOW | RTLD_LOCAL);
#define close_library(handle) dlclose((void*)handle)
#endif

/*
 * Plugin loading functions
 */
namespace DFHack
{
    DBG_DECLARE(core, plugins, DebugCategory::LINFO);

    DFHack::DFLibrary* GLOBAL_NAMES = (DFLibrary*)global_search_handle();

    namespace {
        std::string get_error()
        {
#ifdef WIN32
            DWORD error = GetLastError();
            LPSTR buf = NULL;
            DWORD len = FormatMessageA(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
                NULL, error, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), (LPSTR)&buf, 0, NULL);
            if (len > 0) {
                std::string message{ buf };
                LocalFree(buf);
                return message;
            }
            std::ostringstream b{};
            b << "unknown error " << error;
            return b.str();
#else
            char* error = dlerror();
            if (error)
                return std::string{ error };
            return std::string{};
#endif
        }
    }

    DFLibrary * OpenPlugin (std::filesystem::path filename)
    {
        clear_error();
        DFLibrary* ret = (DFLibrary*)load_library(filename);
        if (!ret) {
            auto error = get_error();
            WARN(plugins).print("OpenPlugin on {} failed: {}\n", filename.string(), error);
        }
        return ret;
    }
    void * LookupPlugin (DFLibrary * plugin ,const char * function)
    {
        return (void *) get_function_address(plugin, function);
    }
    bool ClosePlugin (DFLibrary * plugin)
    {
        int res = close_library(plugin);
        if (res != 0)
        {
            auto error = get_error();
            WARN(plugins).print("ClosePlugin failed: {}\n", error);
        }
        return (res == 0);

    }
}