#include "tier0/platform.h"
#include "tier0/lib.h"
#include "stdarg.h"
#include "unistd.h"
#include "sys/stat.h"
#include "execinfo.h"
#include "dirent.h"
#include "dlfcn.h"
#include "time.h"

PLATFORM_INTERFACE void Plat_FatalErrorFunc(const char* szFormat, ...)
{
	va_list list;
	va_start(list, szFormat);
	V_vprintf(szFormat, list);
	va_end(list);
	fflush(stdout);
	_exit(1);
}

PLATFORM_INTERFACE void Plat_ListDirRecursive(const char* szPath, ListDirCallbackFn file, ListDirCallbackFn dir)
{
	struct dirent *entry;
	DIR *dp = opendir(szPath);

	if (!dp) {
		return;
	}

	while ((entry = readdir(dp)) != NULL) {
		char full_path[1024];
		if (strcmp(entry->d_name, ".") == 0 || strcmp(entry->d_name, "..") == 0)
			continue;

		snprintf(full_path, sizeof(full_path), "%s/%s", szPath, entry->d_name);

		struct stat statbuf;
		if (stat(full_path, &statbuf) == -1) {
			continue;
		}

		if (S_ISDIR(statbuf.st_mode)) {
			if (dir)
				dir(full_path);
			Plat_ListDirRecursive(full_path, file, dir);
		} else {
			if (file)
				file(full_path);
		}
	}

	closedir(dp);
}
PLATFORM_INTERFACE void Plat_ListDir(const char* szPath, ListDirCallbackFn file, ListDirCallbackFn dir)
{

}

PLATFORM_INTERFACE char *Plat_GetExtension( const char *szPath )
{
	char *last = (char*)szPath + V_strlen(szPath) - 1;
	while (last != szPath)
	{
		if (*last=='.')
		{
			break;
		};
		if (*last=='/')
		{
			return 0;
		}
		last--;
	}
	return last+1;
}

PLATFORM_INTERFACE void Plat_Backtrace( void )
{
	void *buffer[64];
	int nptrs = backtrace(buffer, 64);
	char **symbols = backtrace_symbols(buffer, nptrs);

	if (symbols == NULL) {
		V_printf("Backtrace failed\n");
		exit(EXIT_FAILURE);
	}

	for (int i = 0; i < nptrs; i++) {
		V_printf(" [%d]   %s\n", i, symbols[i]);
	}

	free(symbols);
};

PLATFORM_INTERFACE void *Plat_LoadLibrary( const char *psz )
{
	void *lib = dlopen(psz, RTLD_GLOBAL | RTLD_NOW);
	if (!lib)
		V_printf("Failed to open %s\n\t%s\n", psz, dlerror());
	return lib;
}
PLATFORM_INTERFACE void *Plat_GetProc( void *lib, const char *psz )
{
	return dlsym(lib, psz);
}
PLATFORM_INTERFACE void Plat_UnloadLibrary( void *lib )
{
	dlclose(lib);
};

PLATFORM_INTERFACE double Plat_GetTime( void )
{
	struct timespec tp;
	clock_gettime(CLOCK_MONOTONIC, &tp);
	static time_t s_starttime = tp.tv_sec;

	return (tp.tv_sec-s_starttime)+tp.tv_nsec/1e9;
}