#include "hdir.h"

#include "hplatform.h"

#ifdef OS_WIN
//FILETIME starts from 1601年01月01日 UTC, epoch from 1970年01月01日 UTC
//FILETIME unit (100ns)
#define FILETIME_EPOCH_DIFF 11644473600 // s
time_t FileTime2Epoch(FILETIME filetime) {
 uint64_t ll = (((uint64_t)filetime.dwHighDateTime) << 32) | filetime.dwLowDateTime;
 ll /= 1e7; // s
 return ll - FILETIME_EPOCH_DIFF;
}
#endif

static bool less(const hdir_t& lhs, const hdir_t& rhs) {
 return stricmp(lhs.name, rhs.name) < 0;
}

int listdir(const char* dir, std::list<hdir_t>& dirs) {
 int dirlen = strlen(dir);
 if (dirlen > 256) {
 return -1;
 }
 char path[512];
 strcpy(path, dir);
 if (dir[dirlen-1] != '/') {
 strcat(path, "/");
 ++dirlen;
 }
 dirs.clear();
#ifdef OS_UNIX
 // opendir -> readdir -> closedir
 DIR* dp = opendir(dir);
 if (dp == NULL) return -1;
 struct dirent* result = NULL;
 struct stat st;
 hdir_t tmp;
 while ((result = readdir(dp))) {
 memset(&tmp, 0, sizeof(hdir_t));
 strncpy(tmp.name, result->d_name, sizeof(tmp.name));
 strncpy(path+dirlen, result->d_name, sizeof(path)-dirlen);
 if (lstat(path, &st) == 0) {
 if (S_ISREG(st.st_mode)) tmp.type = 'f';
 else if (S_ISDIR(st.st_mode)) tmp.type = 'd';
 else if (S_ISLNK(st.st_mode)) tmp.type = 'l';
 else if (S_ISBLK(st.st_mode)) tmp.type = 'b';
 else if (S_ISCHR(st.st_mode)) tmp.type = 'c';
 else if (S_ISSOCK(st.st_mode)) tmp.type = 's';
 else if (S_ISFIFO(st.st_mode)) tmp.type = 'p';
 else tmp.type = '-';
 tmp.mode = st.st_mode & 0777;
 tmp.size = st.st_size;
 tmp.atime = st.st_atime;
 tmp.mtime = st.st_mtime;
 tmp.ctime = st.st_ctime;
 }
 dirs.push_back(tmp);
 }
 closedir(dp);
#elif defined(OS_WIN)
 // FindFirstFile -> FindNextFile -> FindClose
 strcat(path, "*");
 WIN32_FIND_DATAA data;
 HANDLE h = FindFirstFileA(path, &data);
 if (h == NULL) {
 return -1;
 }
 hdir_t tmp;
 do {
 memset(&tmp, 0, sizeof(hdir_t));
 strncpy(tmp.name, data.cFileName, sizeof(tmp.name));
 tmp.type = 'f';
 if (data.dwFileAttributes & _A_SUBDIR) {
 tmp.type = 'd';
 }
 tmp.mode = 0777;
 tmp.size = (((uint64_t)data.nFileSizeHigh) << 32) | data.nFileSizeLow;
 tmp.atime = FileTime2Epoch(data.ftLastAccessTime);
 tmp.mtime = FileTime2Epoch(data.ftLastWriteTime);
 tmp.ctime = FileTime2Epoch(data.ftCreationTime);
 dirs.push_back(tmp);
 } while (FindNextFileA(h, &data));
 FindClose(h);
#endif
 dirs.sort(less);
 return dirs.size();
}