#ifndef PROGRAM_NAME_HPP
#define PROGRAM_NAME_HPP

#include <mutex>
#include <string>

#if defined(_WIN32)
#include <windows.h>

namespace cpptrace {
    namespace detail {
        inline std::string program_name() {
            static std::mutex mutex;
            const std::lock_guard<std::mutex> lock(mutex);
            static std::string name;
            static bool did_init = false;
            static bool valid = false;
            if(!did_init) {
                did_init = true;
                char buffer[MAX_PATH + 1];
                int res = GetModuleFileNameA(nullptr, buffer, MAX_PATH);
                if(res) {
                    name = buffer;
                    valid = true;
                }
            }
            return valid && !name.empty() ? name.c_str() : nullptr;
        }
    }
}

#elif defined(__APPLE__)

#include <cstdint>
#include <mach-o/dyld.h>
#include <sys/syslimits.h>

namespace cpptrace {
    namespace detail {
        inline const char* program_name() {
            static std::mutex mutex;
            const std::lock_guard<std::mutex> lock(mutex);
            static std::string name;
            static bool did_init = false;
            static bool valid = false;
            if(!did_init) {
                did_init = true;
                std::uint32_t bufferSize = PATH_MAX + 1;
                char buffer[bufferSize];
                if(_NSGetExecutablePath(buffer, &bufferSize) == 0) {
                    name.assign(buffer, bufferSize);
                    valid = true;
                }
            }
            return valid && !name.empty() ? name.c_str() : nullptr;
        }
    }
}

#elif defined(__linux__)

#include <linux/limits.h>
#include <sys/types.h>
#include <unistd.h>

namespace cpptrace {
    namespace detail {
        inline const char* program_name() {
            static std::mutex mutex;
            const std::lock_guard<std::mutex> lock(mutex);
            static std::string name;
            static bool did_init = false;
            static bool valid = false;
            if(!did_init) {
                did_init = true;
                char buffer[PATH_MAX + 1];
                const ssize_t size = readlink("/proc/self/exe", buffer, PATH_MAX);
                if(size == -1) {
                    return nullptr;
                }
                buffer[size] = 0;
                name = buffer;
                valid = true;
            }
            return valid && !name.empty() ? name.c_str() : nullptr;
        }
    }
}

#endif

#endif